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Sample records for reference dosimetry based

  1. Medical reference dosimetry using EPR measurements of alanine

    DEFF Research Database (Denmark)

    Helt-Hansen, Jakob; Rosendal, F.; Kofoed, I.M.

    2009-01-01

    Background. Electron spin resonance (EPR) is used to determine the absorbed dose of alanine dosimeters exposed to clinical photon beams in a solid-water phantom. Alanine is potentially suitable for medical reference dosimetry, because of its near water equivalence over a wide energy spectrum, low...... methods the proposed algorithm can be applied without normalisation of phase shifts caused by changes in the g-value of the cavity. The study shows that alanine dosimetry is a suitable candidate for medical reference dosimetry especially for quality control applications.......Background. Electron spin resonance (EPR) is used to determine the absorbed dose of alanine dosimeters exposed to clinical photon beams in a solid-water phantom. Alanine is potentially suitable for medical reference dosimetry, because of its near water equivalence over a wide energy spectrum, low...

  2. Reference dosimetry of proton pencil beams based on dose-area product: a proof of concept.

    Science.gov (United States)

    Gomà, Carles; Safai, Sairos; Vörös, Sándor

    2017-06-21

    This paper describes a novel approach to the reference dosimetry of proton pencil beams based on dose-area product ([Formula: see text]). It depicts the calibration of a large-diameter plane-parallel ionization chamber in terms of dose-area product in a 60 Co beam, the Monte Carlo calculation of beam quality correction factors-in terms of dose-area product-in proton beams, the Monte Carlo calculation of nuclear halo correction factors, and the experimental determination of [Formula: see text] of a single proton pencil beam. This new approach to reference dosimetry proves to be feasible, as it yields [Formula: see text] values in agreement with the standard and well-established approach of determining the absorbed dose to water at the centre of a broad homogeneous field generated by the superposition of regularly-spaced proton pencil beams.

  3. A Finnish national code of practice for reference dosimetry of radiation therapy

    International Nuclear Information System (INIS)

    Kosunen, A.; Sipilae, P.; Jaervinen, H.; Parkkinen, R.; Jokelainen, I.

    2002-01-01

    Full text: A national Code of Practice (CoP) for reference dosimetry of radiation therapy in Finland will be established during 2002 and will be implemented from the beginning of 2003. The CoP will cover dosimetry of the conventional radiotherapy modalities used in Finland i.e. external radiotherapy with megavoltage photon and electron beams, external radiotherapy with low energy kilovoltage X-ray beams and brachytherapy. The formalisms for external radiation beam dosimetry are those of TRS 389. For brachytherapy the formalism will follow the general guidelines of TECDOC-1274. The CoP will be prepared by the SSDL of STUK in close co-operation with the Finnish radiotherapy physicists. For external beam radiotherapy, the main objective of the national Code of Practice for radiation therapy dosimetry is to maintain the achieved good level of consistency of the dosimetry procedures in external beam radiotherapy as the 'absorbed dose to water' based approach of TRS 389 is implemented in Finland. In the CoP the dosimetry the procedures are described for the whole dosimetry chain starting from the calibration of the ionisation chambers at the SSDL of STUK and ending to the calibration of the beam monitor ionisation chamber of a linear accelerator. For brachytherapy dosimetry the aim is to fix the national practice for reference air kerma rate calibrations both for radioactive sources and for well-type ionisation chambers. Although the dosimetry procedures are described independently of the SSDL service, CoP makes use of the special features of the calibration service offered by the SSDL of STUK. For ionisation chambers used for photon dosimetry the calibration factors for the user measurement chain are given not only for the actual reference beam quality ( 60 Co) but also for a set of user beam qualities. Furthermore, SSDL of STUK offers calibration services for plane parallel ionisation chambers in an electron beam of a user linac. For brachytherapy SSDL of STUK has

  4. Reference dosimetry for helical tomotherapy: Practical implementation and a multicenter validation

    International Nuclear Information System (INIS)

    De Ost, B.; Schaeken, B.; Vynckier, S.; Sterpin, E.; Van den Weyngaert, D.

    2011-01-01

    Purpose: The aim of this study was to implement a protocol for reference dosimetry in tomotherapy and to validate the beam output measurements with an independent dosimetry system. Methods: Beam output was measured at the reference depth of 10 cm in water for the following three cases: (1) a 5 x 10 cm 2 static machine specific reference field (MSR), (2) a rotational 5 x 10 cm 2 field without modulation and no tabletop in the beam, (3) a plan class specific reference (PCSR) field defined as a rotational homogeneous dose delivery to a cylindrical shaped target volume: plan with modulation and table-top movement. The formalism for reference dosimetry of small and nonstandard fields [Med.Phys.35: 5179-5186, 2008] and QA recommendations [Med.Phys.37: 4817-4853, 2010] were adopted in the dose measurement protocol. All ionization chamber measurements were verified independently using alanine/EPR dosimetry. As a pilot study, the beam output was measured on tomotherapy Hi-art systems at three other centers and directly compared to the centers specifications and to alanine dosimetry. Results: For the four centers, the mean static output at a depth of 10 cm in water and SAD = 85 cm, measured with an A1SL chamber following the TG-148 report was 6.238 Gy/min ± 0.058 (1 SD); the rotational output was 6.255 Gy/min ± 0.069 (1 SD). The dose stated by the center was found in good agreement with the measurements of the visiting team: D center /D visit = 1.000 ± 0.003 (1 SD). The A1SL chamber measurements were all in good agreement with Alanine/EPR dosimetry. Going from the static reference field to the rotational/non modulated field the dose rate remains constant within 0.2% except for one center where a deviation of 1.3% was detected. Conclusions: Following the TG-148 report, beam output measurements in water at the reference depth using a local protocol, as developed at different centers, was verified. The measurements were found in good agreement with alanine/EPR dosimetry. The

  5. Reference dosimetry and small-field dosimetry in external beam radiotherapy: Results from a Danish intercomparison study

    DEFF Research Database (Denmark)

    Beierholm, Anders Ravnsborg; Behrens, Claus F.; Sibolt, Patrik

    methods was performed by DTU Nutech at six Danish clinics. The first part of the intercompa-rison regarded the consistency of reference dosimetry. Absorbed dose to water under reference conditions was measured using a Farmer ionization chamber, and was found to agree within 1 % with the daily dose checks......-specific correction factors for non-reference fields....

  6. Optimization of radiation protection in nuclear medicine: from reference dosimetry to personalized dosimetry

    International Nuclear Information System (INIS)

    Hadid, Lama

    2011-01-01

    In nuclear medicine, radiopharmaceuticals are distributed in the body through biokinetic processes. Thus, each organ can become a source of radiation delivering a fraction of emitted energy in tissues. Therefore, dose calculations must be assessed accurately and realistically to ensure the patient radiation protection. Absorbed doses were until now based on mathematical standard models and electron transport approximations. The International Commission on Radiological Protection (ICRP) has recently adopted voxel phantoms as a more realistic representation of the reference adult. The main goal of this thesis was to study the influence of the use of the new reference models and Monte Carlo methods on the major dosimetric quantities. In addition, the contribution of patients? specific geometry to the absorbed dose was compared to a standard geometry, enabling the evaluation of uncertainties arising from the reference values. Particular attention was paid to the bone marrow which is characterized by a high radiosensitivity and a complex microscopic structure. An accurate alpha dosimetry was assessed for bone marrow using microscopic images of several trabecular bone sites. The results showed variations in the absorbed fractions as a function of the particles? energy, the skeletal site and the amount of fat within marrow cavities, three parameters which are not taken into account in the values published by the ICRP. Finally, the heterogeneous activity distribution of the radiopharmaceuticals was considered within the framework of the treatment of a hepato-cellular carcinoma with selective internal radiotherapy using Yttrium-90 through the analysis of dose-volume histograms. The developments made in this thesis show the importance and the feasibility of performing a personalized dosimetry for nuclear medicine patients. (author)

  7. Reference dosimetry for CT in the UK

    International Nuclear Information System (INIS)

    Shrimpton, P.C.; Wall, B.F.

    2001-01-01

    Computed tomography is firmly established as a major source of population exposure from diagnostic x-ray examinations and thus a particular focus for radiological protection initiatives. The concept of reference doses is widely recognised as a useful and practical tool for promoting improvements in the optimisation of protection for patients undergoing radiological examinations. National diagnostic reference levels (DRLs) have already been successfully applied in the UK for some conventional x-ray examinations within a framework for advice on patient protection. This approach is being extended to include CT, utilising the robust methodology for reference dosimetry that has been developed by the European Commission (EC) for the particular conditions of exposure in CT. This is based on the dosimetric concepts of weighted computed tomography dose index (CTDI w ) per slice in serial scanning or per rotation in helical scanning, and dose-length product (DLP) per complete examination. Notwithstanding some initial values proposed by the EC, specific national DRLs for CT practice in the UK will be established on the basis of widescale national survey data. (author)

  8. Certification of a copper metal reference material for neutron dosimetry. (EC nuclear reference material 522)

    International Nuclear Information System (INIS)

    Ingelbrecht, C.; Pauwels, J.; Lievens, F.

    1993-01-01

    Copper metal of ≥ 99.995% nominal purity in the form of 0.1 and 1.0 mm thick foil and 0.5 and 1.0 mm diameter wire has been certified for its cobalt and silver mass fractions. The certified values are -1 and 0.95 ± 0.04 mg.kg -1 respectively, based on 66 results for cobalt and 88 results for silver obtained by nine laboratories using three methods. This reference material, EC-NRM 522, is intended for reactor neutron dosimetry. (authors). 14 refs., 1 annexe, 10 tabs., 2 figs

  9. Certification of an iron metal reference material for neutron dosimetry (EC nuclear reference material 524)

    International Nuclear Information System (INIS)

    Ingelbrecht, C.; Pauwels, J.; Lievens, F.

    1993-01-01

    Iron metal, of > 99.996% nominal purity, in the form of 0.1 mm thick foil and of 0.5 mm diameter wire has been certified for its manganese and cobalt mass fractions. The certified value of the cobalt mass fraction ( -1 ) is based on 39 accepted results from five laboratories using two different methods. The certified value of the manganese mass fraction ( -1 ) is based on 41 accepted results from five laboratories using three different methods. The overall purity was also verified. The material is intended to be used as a reference material in neutron dosimetry. (authors). 8 refs., 9 tabs., 2 figs

  10. Comparison of Real-Time Intraoperative Ultrasound-Based Dosimetry With Postoperative Computed Tomography-Based Dosimetry for Prostate Brachytherapy

    International Nuclear Information System (INIS)

    Nag, Subir; Shi Peipei; Liu Bingren; Gupta, Nilendu; Bahnson, Robert R.; Wang, Jian Z.

    2008-01-01

    Purpose: To evaluate whether real-time intraoperative ultrasound (US)-based dosimetry can replace conventional postoperative computed tomography (CT)-based dosimetry in prostate brachytherapy. Methods and Materials: Between December 2001 and November 2002, 82 patients underwent 103 Pd prostate brachytherapy. An interplant treatment planning system was used for real-time intraoperative transrectal US-guided treatment planning. The dose distribution was updated according to the estimated seed position to obtain the dose-volume histograms. Postoperative CT-based dosimetry was performed a few hours later using the Theraplan-Plus treatment planning system. The dosimetric parameters obtained from the two imaging modalities were compared. Results: The results of this study revealed correlations between the US- and CT-based dosimetry. However, large variations were found in the implant-quality parameters of the two modalities, including the doses covering 100%, 90%, and 80% of the prostate volume and prostate volumes covered by 100%, 150%, and 200% of the prescription dose. The mean relative difference was 38% and 16% for doses covering 100% and 90% of the prostate volume and 10% and 21% for prostate volumes covered by 100% and 150% of the prescription dose, respectively. The CT-based volume covered by 200% of the prescription dose was about 30% greater than the US-based one. Compared with CT-based dosimetry, US-based dosimetry significantly underestimated the dose to normal organs, especially for the rectum. The average US-based maximal dose and volume covered by 100% of the prescription dose for the rectum was 72 Gy and 0.01 cm 3 , respectively, much lower than the 159 Gy and 0.65 cm 3 obtained using CT-based dosimetry. Conclusion: Although dosimetry using intraoperative US-based planning provides preliminary real-time information, it does not accurately reflect the postoperative CT-based dosimetry. Until studies have determined whether US-based dosimetry or

  11. Dosimetry-based treatment planning for molecular radiotherapy: a summary of the 2017 report from the Internal Dosimetry Task Force

    Directory of Open Access Journals (Sweden)

    Caroline Stokke

    2017-11-01

    Full Text Available Abstract Background The European directive on basic safety standards (Council directive 2013/59 Euratom mandates dosimetry-based treatment planning for radiopharmaceutical therapies. The directive comes into operation February 2018, and the aim of a report produced by the Internal Dosimetry Task Force of the European Association of Nuclear Medicine is to address this aspect of the directive. A summary of the report is presented. Results A brief review of five of the most common therapy procedures is included in the current text, focused on the potential to perform patient-specific dosimetry. In the full report, 11 different therapeutic procedures are included, allowing additional considerations of effectiveness, references to specific literature on quantitative imaging and dosimetry, and existing evidence for absorbed dose-effect correlations for each treatment. Individualized treatment planning with tracer diagnostics and verification of the absorbed doses delivered following therapy is found to be scientifically feasible for almost all procedures investigated, using quantitative imaging and/or external monitoring. Translation of this directive into clinical practice will have significant implications for resource requirements. Conclusions Molecular radiotherapy is undergoing a significant expansion, and the groundwork for dosimetry-based treatment planning is already in place. The mandated individualization is likely to improve the effectiveness of the treatments, although must be adequately resourced.

  12. Poster - 19: Investigation of Electron Reference Dosimetry Based on Optimal Chamber Shift

    Energy Technology Data Exchange (ETDEWEB)

    Zhan, Lixin; Jiang, Runqing; Liu, Baochang; Osei, Ernest [Grand River Regional Cancer Centre (Canada)

    2016-08-15

    An addendum/revision to AAPM TG-51 electron reference dosimetry is highly expected to meet the clinical requirement with the increasing usage of new ion chambers not covered in TG-51. A recent study, Med. Phys. 41, 111701, proposed a new fitting equation for the beam quality conversion factor k’{sub Q} to a wide spectrum of chambers. In the study, an optimal Effective Point of Measurement (EPOM) from Monte Carlo calculations was recommended and the fitting parameters to k’{sub Q} was based on it. We investigated the absolute dose obtained based on the optimal EPOM method and the original TG-51 method with k’{sub R50} determined differently. The results showed that using the Markus curve is a better choice than the well-guarded chamber fitting for an IBA PPC-05 parallel plate chamber if we need to strictly follow the AAPM TG-51 protocol. We also examined the usage of the new fitting equation with measurement performed at the physical EPOM, instead of the optimal EPOM. The former is more readily determined and more practical in clinics. Our study indicated that the k’{sub Q} fitting based on the optimal EPOM can be used to measurement at the physical EPOM with no significant clinical impact. The inclusion of Farmer chamber gradient correction P{sub gr} in k’{sub Q}, as in the mentioned study, asks for the precise positioning of chamber center at dref. It is not recommended in clinics to avoid over-correction for low electron energies, especially for an institute having matching Linacs implemented.

  13. Codes of practice and protocols for the dosimetry in reference conditions of proton and ion beams

    International Nuclear Information System (INIS)

    Vatnitsky, S.; Andreo, P.

    2002-01-01

    The advantages of radiotherapy protons and heavier charged-particle beams, the technological feasibility, and the clinical results obtained so far have led to the establishment of about 20 treatment facilities worldwide and plans to open another 20 proton and light-ion therapy centres in the next five years. In order to meet the expanding capabilities of treatment techniques, considerable effort has been devoted during the last fifteen years to the development of the dosimetry and calibration of such beams. This paper reviews these developments and summarizes the present status of Codes of Practice and protocols for the dosimetry in reference conditions of proton and ion beams. The first dosimetry protocol for heavy-particle radiotherapy beams, AAPM TG 20, was based on the use of Faraday cups and calorimeters, whereas ionization chamber dosimetry received little attention. Following the trends in 'nuclear particle' radiotherapy, TG 20 included recommendations for specifying 'dose to tissue'. The lack of availability of a harmonized set of data for the different particles made this protocol to include data for stopping-powers and for the mean energy required to produce and ion pair in air, W air , from multiple authors, without enough attention being paid to their consistency. The increased focus into proton beams was materialized in the publication of the ECHED Code of Practice, dedicated exclusively to protons, where ionization dosimetry received more attention than in TG 20. It was not until the publication of the Supplement to the ECHED recommendations that ionization chambers having a 60 CO calibration factor were recommended as a reference detector for proton dosimetry, and data supplied for chambers with different wall materials. The emphasis on ionization chamber-based proton dosimetry was complemented with a recommendation for using water as dosimetry phantom material and the necessary data on tissue and water to air stopping-power ratios and W air . One of

  14. Alanine dosimetry at NPL - the development of a mailed reference dosimetry service at radiotherapy dose levels

    International Nuclear Information System (INIS)

    Sharpe, P.H.G.; Sephton, J.P.

    1999-01-01

    In this paper we describe the work that has been carried out at National Physical Laboratory (NPL) to develop a mailed alanine reference dosimetry service for radiotherapy dose levels. The service is based on alanine/paraffin wax dosimeters produced at NPL. Using a data analysis technique based on spectrum fitting, it has been possible to achieve a precision of dose measurement better than ±0.05 Gy (1σ). A phantom set has been developed for use in high energy photon beams, which enables simultaneous irradiation of alanine dosimeters and ionisation chambers in a well defined geometry. Studies in photon beams of energies between 60 Co and 20 MeV have shown no significant energy dependence (<1%) for alanine relative to dose determination using a graphite calorimeter. Work is underway to extend the service to electron beams, and preliminary results are presented on the direct calibration of alanine in electron beams using a graphite calorimeter. (author)

  15. Validation of internal dosimetry protocols based on stochastic method

    International Nuclear Information System (INIS)

    Mendes, Bruno M.; Fonseca, Telma C.F.; Almeida, Iassudara G.; Trindade, Bruno M.; Campos, Tarcisio P.R.

    2015-01-01

    Computational phantoms adapted to Monte Carlo codes have been applied successfully in radiation dosimetry fields. NRI research group has been developing Internal Dosimetry Protocols - IDPs, addressing distinct methodologies, software and computational human-simulators, to perform internal dosimetry, especially for new radiopharmaceuticals. Validation of the IDPs is critical to ensure the reliability of the simulations results. Inter comparisons of data from literature with those produced by our IDPs is a suitable method for validation. The aim of this study was to validate the IDPs following such inter comparison procedure. The Golem phantom has been reconfigured to run on MCNP5. The specific absorbed fractions (SAF) for photon at 30, 100 and 1000 keV energies were simulated based on the IDPs and compared with reference values (RV) published by Zankl and Petoussi-Henss, 1998. The SAF average differences from RV and those obtained in IDP simulations was 2.3 %. The SAF largest differences were found in situations involving low energy photons at 30 keV. The Adrenals and thyroid, i.e. the lowest mass organs, had the highest SAF discrepancies towards RV as 7.2 % and 3.8 %, respectively. The statistic differences of SAF applying our IDPs from reference values were considered acceptable at the 30, 100 and 1000 keV spectra. We believe that the main reason for the discrepancies in IDPs run, found in lower masses organs, was due to our source definition methodology. Improvements of source spatial distribution in the voxels may provide outputs more consistent with reference values for lower masses organs. (author)

  16. Validation of internal dosimetry protocols based on stochastic method

    Energy Technology Data Exchange (ETDEWEB)

    Mendes, Bruno M.; Fonseca, Telma C.F., E-mail: bmm@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Almeida, Iassudara G.; Trindade, Bruno M.; Campos, Tarcisio P.R., E-mail: tprcampos@yahoo.com.br [Universidade Federal de Minas Gerais (DEN/UFMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear

    2015-07-01

    Computational phantoms adapted to Monte Carlo codes have been applied successfully in radiation dosimetry fields. NRI research group has been developing Internal Dosimetry Protocols - IDPs, addressing distinct methodologies, software and computational human-simulators, to perform internal dosimetry, especially for new radiopharmaceuticals. Validation of the IDPs is critical to ensure the reliability of the simulations results. Inter comparisons of data from literature with those produced by our IDPs is a suitable method for validation. The aim of this study was to validate the IDPs following such inter comparison procedure. The Golem phantom has been reconfigured to run on MCNP5. The specific absorbed fractions (SAF) for photon at 30, 100 and 1000 keV energies were simulated based on the IDPs and compared with reference values (RV) published by Zankl and Petoussi-Henss, 1998. The SAF average differences from RV and those obtained in IDP simulations was 2.3 %. The SAF largest differences were found in situations involving low energy photons at 30 keV. The Adrenals and thyroid, i.e. the lowest mass organs, had the highest SAF discrepancies towards RV as 7.2 % and 3.8 %, respectively. The statistic differences of SAF applying our IDPs from reference values were considered acceptable at the 30, 100 and 1000 keV spectra. We believe that the main reason for the discrepancies in IDPs run, found in lower masses organs, was due to our source definition methodology. Improvements of source spatial distribution in the voxels may provide outputs more consistent with reference values for lower masses organs. (author)

  17. Participation of the regional reference center for dosimetry of Argentina in the personnel dosimetry intercomparison for Latin America

    International Nuclear Information System (INIS)

    Alvarez, P.; Lindner, C.; Montano, R.G.; Saravi, M.

    1998-01-01

    Full text: A Regional Personnel Dosimetry Intercomparison was organized in the Regional Reference Center for Dosimetry (CRRD), in agreement with the International Atomic Energy Agency (IAEA) and the Nuclear Regulatory Authority (ARN), with the participation of 9 countries of Latin America. For dosimeter irradiations, X-ray, 60 Co γ-ray and 137 Cs γ-ray beams were used during the intercomparison. The air kerma rate was measured with the Secondary Standard NE 2560 and NE 2561 ionisation chamber. In compliance with ISO 4037 guideline, the wide spectrum series W60, W110 and W200 for the X-ray irradiations were chosen, determining their quality by the HVL method. Prior to the intercomparison, these beams were checked by the Physikalish Technische Bundesanstalt (PTB) using thermoluminescence dosimeters 'pill box', which were irradiated in air and in ICRU phantom. As result of this check, only one 'X ray beam got a deviation of 7%, while the rest of them were less than 3%. Periodic checks of the beams by a Primary Standard Dosimetry Laboratory such as PTB give reliability to the irradiations performed by this CRRD. (author) [es

  18. Dosimetry for radiation processing

    DEFF Research Database (Denmark)

    Miller, Arne

    1986-01-01

    During the past few years significant advances have taken place in the different areas of dosimetry for radiation processing, mainly stimulated by the increased interest in radiation for food preservation, plastic processing and sterilization of medical products. Reference services both...... and sterilization dosimetry, optichromic dosimeters in the shape of small tubes for food processing, and ESR spectroscopy of alanine for reference dosimetry. In this paper the special features of radiation processing dosimetry are discussed, several commonly used dosimeters are reviewed, and factors leading...

  19. Clinical dosimetry in photon radiotherapy. A Monte Carlo based investigation

    International Nuclear Information System (INIS)

    Wulff, Joerg

    2010-01-01

    Practical clinical dosimetry is a fundamental step within the radiation therapy process and aims at quantifying the absorbed radiation dose within a 1-2% uncertainty. To achieve this level of accuracy, corrections are needed for calibrated and air-filled ionization chambers, which are used for dose measurement. The procedures of correction are based on cavity theory of Spencer-Attix and are defined in current dosimetry protocols. Energy dependent corrections for deviations from calibration beams account for changed ionization chamber response in the treatment beam. The corrections applied are usually based on semi-analytical models or measurements and are generally hard to determine due to their magnitude of only a few percents or even less. Furthermore the corrections are defined for fixed geometrical reference-conditions and do not apply to non-reference conditions in modern radiotherapy applications. The stochastic Monte Carlo method for the simulation of radiation transport is becoming a valuable tool in the field of Medical Physics. As a suitable tool for calculation of these corrections with high accuracy the simulations enable the investigation of ionization chambers under various conditions. The aim of this work is the consistent investigation of ionization chamber dosimetry in photon radiation therapy with the use of Monte Carlo methods. Nowadays Monte Carlo systems exist, which enable the accurate calculation of ionization chamber response in principle. Still, their bare use for studies of this type is limited due to the long calculation times needed for a meaningful result with a small statistical uncertainty, inherent to every result of a Monte Carlo simulation. Besides heavy use of computer hardware, techniques methods of variance reduction to reduce the needed calculation time can be applied. Methods for increasing the efficiency in the results of simulation were developed and incorporated in a modern and established Monte Carlo simulation environment

  20. A New Dual-purpose Quality Control Dosimetry Protocol for Diagnostic Reference-level Determination in Computed Tomography.

    Science.gov (United States)

    Sohrabi, Mehdi; Parsi, Masoumeh; Sina, Sedigheh

    2018-05-17

    A diagnostic reference level is an advisory dose level set by a regulatory authority in a country as an efficient criterion for protection of patients from unwanted medical exposure. In computed tomography, the direct dose measurement and data collection methods are commonly applied for determination of diagnostic reference levels. Recently, a new quality-control-based dose survey method was proposed by the authors to simplify the diagnostic reference-level determination using a retrospective quality control database usually available at a regulatory authority in a country. In line with such a development, a prospective dual-purpose quality control dosimetry protocol is proposed for determination of diagnostic reference levels in a country, which can be simply applied by quality control service providers. This new proposed method was applied to five computed tomography scanners in Shiraz, Iran, and diagnostic reference levels for head, abdomen/pelvis, sinus, chest, and lumbar spine examinations were determined. The results were compared to those obtained by the data collection and quality-control-based dose survey methods, carried out in parallel in this study, and were found to agree well within approximately 6%. This is highly acceptable for quality-control-based methods according to International Atomic Energy Agency tolerance levels (±20%).

  1. The international protocol for the dosimetry of external radiotherapy beams based on standards of absorbed dose to water

    International Nuclear Information System (INIS)

    Andreo, P.

    2001-01-01

    An International Code of Practice (CoP, or dosimetry protocol) for external beam radiotherapy dosimetry based on standards of absorbed dose to water has been published by the IAEA on behalf of IAEA, WHO, PAHO and ESTRO. The CoP provides a systematic and internationally unified approach for the determination of the absorbed dose to water in reference conditions with radiotherapy beams. The development of absorbed-dose-to-water standards for high-energy photons and electrons offers the possibility of reducing the uncertainty in the dosimetry of radiotherapy beams. Many laboratories already provide calibrations at the radiation quality of 60Co gamma-rays and some have extended calibrations to high-energy photon and electron beams. The dosimetry of kilovoltage x-rays, as well as that of proton and ion beams can also be based on these standards. Thus, a coherent dosimetry system based on the same formalism is achieved for practically all radiotherapy beams. The practical use of the CoP as simple. The document is formed by a set of different CoPs for each radiation type, which include detailed procedures and worksheets. All CoPs are based on ND,w chamber calibrations at a reference beam quality Qo, together with radiation beam quality correction factors kQ preferably measured directly for the user's chamber in a standards laboratory. Calculated values of kQ are provided together with their uncertainty estimates. Beam quality specifiers are 60Co, TPR20,10 (high-energy photons), R50 (electrons), HVL and kV (x-rays) and Rres (protons and ions) [es

  2. Dosimetry

    International Nuclear Information System (INIS)

    Rezende, D.A.O. de

    1976-01-01

    The fundamental units of dosimetry are defined, such as exposure rate, absorbed dose and equivalent dose. A table is given of relative biological effectiveness values for the different types of radiation. The relation between the roentgen and rad units is calculated and the concepts of physical half-life, biological half-life and effective half-life are discussed. Referring to internal dosimetry, a mathematical treatment is given to β particle-and γ radiation dosimetry. The absorbed dose is calculated and a practical example is given of the calculation of the exposure and of the dose rate for a gama source [pt

  3. Reference man models based on normal data from human populations

    International Nuclear Information System (INIS)

    Tanaka, Gi-ichiro; Kawamura, Hisao

    2000-01-01

    Quantitative description of the physical, and metabolic parameters of the human body is the very basic for internal dosimetry. Compilation of anatomical and other types of data Asian populations for internal (and external) dosimetry is of grate significance because of the potential spread of nuclear energy use in the Asian region and the major contribution of the region to the world population (about 58%). It has been observed that some differences exist for habitat, race, body sizes and pattern of food consumption. In the early stage of revision of ICRP Reference man by the Task Group, Characteristics of the human body of non-European populations received considerable attention as well as those of the European populations of different sexes and ages. In this context, an IAEA-RCA Co-ordinated Research Program on Compilation of Anatomical, Physiological and Metabolic Characteristics for a Reference Asian Man endorsed. In later stages of reference Man revision, anatomical data for Asians was discusses together with those of European populations, presumably due to ICRP's decision of unanimous use of the Reference Man for radiation protection. Reference man models for adults and 15, 10, 5, 1, 0 year-old males and females of Asian populations were developed for use in internal and external dosimetry. Based on the concept of ICRP Reference Man (Publication 23), the reference values were derived from the normal organ mass data for Japanese and statistical data on the physique and nutrition of Japanese and Chinese. Also incorporated were variations in physical measurements, as observed in the above mentioned IAEA-RCA Co-ordinated Research Program. The work was partly carried out within the activities of the ICRP Task Group on Reference Man. The weight of the skeleton was adjusted following the revised values in Publication 70. This paper will report basic shared and non-shared characteristics of Reference Man' for Asians and ICRP Reference Man. (author)

  4. A new method for dosimetry with films radiochromic

    International Nuclear Information System (INIS)

    Mendez Carot, I.

    2013-01-01

    in this paper a new method is presented and the results of the comparison between the calibration is summarized based on a planning reference and calibration obtained from the irradiated fragments measure different dose levels multichannel compare dosimetry based on the weighted average dosimetry described by Micke et al.(present in the FilmQAPro software) and, finally, show different results obtained with the method proposed in several applications clinics. (Author)

  5. Radiotherapy Based On α Emitting Radionuclides: Geant4 For Dosimetry And Micro-/Nano-Dosimetry

    International Nuclear Information System (INIS)

    Guatelli, Susanna

    2013-01-01

    Possible physics approaches to evaluate the efficacy of TAT are dosimetry, microdosimetry and nanodosimetry. Dosimetry is adequate when mean absorbed dose to a macroscopic target volume is important to understand the biological effect of radiation. General purpose Monte Carlo (MC) codes, based on condensed history approach, are a very useful, cost effective tool to solve dosimetric problems. The condensed history approach is based on the use of multiple scattering theories to calculate the energy losses and angular changes in the direction of the particle. The short α particle range and high LET make the microdosimetric approach more suitable than dosimetry to study TAT from first physics principles, as this approach takes into account the stochastic nature of energy deposition at cellular level

  6. Medical reference dosimetry using EPR measurements of alanine: Development of an improved method for clinical dose levels

    International Nuclear Information System (INIS)

    Helt-Hansen, Jakob; Andersen, Claus Erik; Rosendal, Flemming; Kofoed, Inger Matilde

    2009-01-01

    Electron spin resonance (EPR) is used to determine the absorbed dose of alanine dosimeters exposed to clinical photon beams in a solid-water phantom. Alanine is potentially suitable for medical reference dosimetry, because of its near water equivalence over a wide energy spectrum, low signal fading, non-destructive measurement and small dosimeter size. Material and Methods. A Bruker EMX-micro EPR spectrometer with a rectangular cavity and a measurement time of two minutes per dosimeter was used for reading of irradiated alanine dosimeters. Under these conditions a new algorithm based on scaling of known spectra was developed to extract the alanine signal. Results. The dose accuracy, including calibration uncertainty, is less than 2% (k=1) above 4 Gy (n=4). The measurement uncertainty is fairly constant in absolute terms (∼30 mGy) and the relative uncertainty therefore rises for dose measurements below 4 Gy. Typical reproducibility is <1% (k=1) above 10 Gy and <2% between 4 and 10 Gy. Below 4 Gy the uncertainty is higher. A depth dose curve measurement was performed in a solid-water phantom irradiated to a dose of 20 Gy at the maximum dose point (dmax) in 6 and 18 MV photon beams. The typical difference between the dose measured with alanine in solid water and the dose measured with an ion chamber in a water tank was about 1%. A difference of 2% between 6 and 18 MV was found, possibly due to non-water equivalence of the applied phantom. Discussion. Compared to previously published methods the proposed algorithm can be applied without normalisation of phase shifts caused by changes in the g-value of the cavity. The study shows that alanine dosimetry is a suitable candidate for medical reference dosimetry especially for quality control applications

  7. Dosimetry and operation of irradiation facilities

    International Nuclear Information System (INIS)

    Vidal, P.E.

    1985-01-01

    The industrial use of ionizing radiation has required, from the very first, the measurement of delivered and absorbed doses; hence the necessity of providing dosimetric systems. Laboratories, scientists, industries and potential equipment manufacturers have all collaborated in this new field of activity. Dosimetric intercomparisons have been made by each industry at their own facilities and in collaboration with specialists, national organizations and the IAEA. Dosimetry has become a way of ensuring that treatment by irradiation has been carried out in accordance with the rules. It has become in effect assurance of quality. Routine dosimetry should determine a maximum and minimum dose. Numerous factors play a part in dosimetry. Industry is currently in possession of routine dosimetric systems that are sufficiently accurate, fairly easy to handle and reasonable in cost, thereby satisfying all the requirements of industry and the need for control. Dosimetry is important in the process of marketing irradiated products. The operator of an industrial irradiation facility bases his dosimetry on comparison with reference systems. Research aimed at simplifying the practice of routine dosimetry should be continued. New physical and chemical techniques will be incorporated into systems already in use. The introduction of microcomputers into the operation of radiation facilities has increased the value of dosimetry and made the conditions of treatment more widespread. Stress should be placed on research in several areas apart from reference systems, for example: dosimetric systems at temperatures from +8 deg. C to -45 deg. C, over the dose range 100 krad to a little more than 1 Mrad, liquids and fluidized solids carried at high speed through ducts, thin-film liquids circulating at a high flow rate, and various other problems. (author)

  8. Advances in reference and transfer dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Desrosiers, M.F. [Ionizing Radiation Division, Physics Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States)

    1999-07-01

    All prerequisites are now in place to create a fundamentally and radically different type of calibration service for the radiation processing industry. Advancements in dosimetry and information technology can be combined to provide industry with on-line calibrations, on demand at a low cost. The remote calibration service will serve as a basis for other areas of metrology. (Author)

  9. Advances in reference and transfer dosimetry

    International Nuclear Information System (INIS)

    Desrosiers, M.F.

    1999-01-01

    All prerequisites are now in place to create a fundamentally and radically different type of calibration service for the radiation processing industry. Advancements in dosimetry and information technology can be combined to provide industry with on-line calibrations, on demand at a low cost. The remote calibration service will serve as a basis for other areas of metrology. (Author)

  10. Worldwide QA networks for radiotherapy dosimetry

    International Nuclear Information System (INIS)

    Izewska, J.; Svensson, H.; Ibbott, G.

    2002-01-01

    A number of national or international organizations have developed various types and levels of external audits for radiotherapy dosimetry. There are three major programmes who make available external audits, based on mailed TLD (thermoluminescent dosimetry), to local radiotherapy centres on a regular basis. These are the IAEA/WHO TLD postal dose audit service operating worldwide, the European Society for Therapeutic Radiology and Oncology (ESTRO) system, EQUAL, in European Union (EU) and the Radiological Physics Center (RPC) in North America. The IAEA, in collaboration with WHO, was the first organization to initiate TLD audits on an international scale in 1969, using mailed system, and has a well-established programme for providing dose verification in reference conditions. Over 32 years, the IAEA/WHO TLD audit service has checked the calibration of more than 4300 radiotherapy beams in about 1200 hospitals world-wide. Only 74% of those hospitals who receive TLDs for the first time have results with deviation between measured and stated dose within acceptance limits of ±5%, while approximately 88% of the users that have benefited from a previous TLD audit are successful. EQUAL, an audit programme set up in 1998 by ESTRO, involves the verification of output for high energy photon and electron beams, and the audit of beam parameters in non-reference conditions. More than 300 beams are checked each year, mainly in the countries of EU, covering approximately 500 hospitals. The results show that although 98% of the beam calibrations are within the tolerance level of ±5%, a second check was required in 10% of the participating centres, because a deviation larger than ±5% was observed in at least one of the beam parameters in non-reference conditions. EQUAL has been linked to another European network (EC network) which tested the audit methodology prior to its application. The RPC has been funded continuously since 1968 to monitor radiation therapy dose delivery at

  11. Chemical dosimetry system for criticality accidents.

    Science.gov (United States)

    Miljanić, Saveta; Ilijas, Boris

    2004-01-01

    Ruder Bosković Institute (RBI) criticality dosimetry system consists of a chemical dosimetry system for measuring the total (neutron + gamma) dose, and a thermoluminescent (TL) dosimetry system for a separate determination of the gamma ray component. The use of the chemical dosemeter solution chlorobenzene-ethanol-trimethylpentane (CET) is based on the radiolytic formation of hydrochloric acid, which protonates a pH indicator, thymolsulphonphthalein. The high molar absorptivity of its red form at 552 nm is responsible for a high sensitivity of the system: doses in the range 0.2-15 Gy can be measured. The dosemeter has been designed as a glass ampoule filled with the CET solution and inserted into a pen-shaped plastic holder. For dose determinations, a newly constructed optoelectronic reader has been used. The RBI team took part in the International Intercomparison of Criticality Accident Dosimetry Systems at the SILENE Reactor, Valduc, June 2002, with the CET dosimetry system. For gamma ray dose determination TLD-700 TL detectors were used. The results obtained with CET dosemeter show very good agreement with the reference values.

  12. Secondary standard dosimetry laboratory (SSDL)

    International Nuclear Information System (INIS)

    Md Saion bin Salikin.

    1983-01-01

    A secondary Standard Dosimetry Laboratory has been established in the Tun Ismail Research Centre, Malaysia as a national laboratory for reference and standardization purposes in the field of radiation dosimetry. This article gives brief accounts on the general information, development of the facility, programmes to be carried out as well as other information on the relevant aspects of the secondary standard dosimetry laboratory. (author)

  13. Alanine dosimetry for clinical applications. Proceedings

    International Nuclear Information System (INIS)

    Anton, M.

    2006-05-01

    The following topics are dealt with: Therapy level alanine dosimetry at the UK Nationational Physical Laboratory, alanine as a precision validation tool for reference dosimetry, composition of alanine pellet dosimeters, the angular dependence of the alanine ESR spectrum, the CIAE alanine dosimeter for radiotherapy level, a correction for temporal evolution effects in alanine dosimetry, next-generation services foe e-traceability to ionization radiation national standards, establishing e-traceability to HIST high-dose measurement standards, alanine dosimetry of dose delivery from clinical accelerators, the e-scan alanine dosimeter reader, alanine dosimetry at ISS, verification of the integral delivered dose for IMRT treatment in the head and neck region with ESR/alanine dosimetry, alanine dosimetry in helical tomotherapy beams, ESR dosimetry research and development at the University of Palermo, lithium formate as a low-dose EPR radiation dosimeter, sensitivity enhancement of alanine/EPR dosimetry. (HSI)

  14. Dosimetry for radiation processing

    International Nuclear Information System (INIS)

    Miller, Arne

    1986-01-01

    During the past few years significant advances have taken place in the different areas of dosimetry for radiation processing, mainly stimulated by the increased interest in radiation for food preservation, plastic processing and sterilization of medical products. Reference services both by international organizations (IAEA) and national laboratories have helped to improve the reliability of dose measurements. In this paper the special features of radiation processing dosimetry are discussed, several commonly used dosimeters are reviewed, and factors leading to traceable and reliable dosimetry are discussed. (author)

  15. TRS 398 dosimetry protocol for radiotherapy

    International Nuclear Information System (INIS)

    Palmans, H.; Smyth, V.

    2004-01-01

    Full text: In recent years, international codes of practice based on absorbed dose to water standards have been published for the clinical reference dosimetry of external beams. It has become widely accepted that dosimetry of radiotherapeutic beams should be based on these standards. These codes of practice are a major improvement over earlier ones that used air kerma calibration factors as they are based on a calibration directly in a phantom in terms of the quantity of interest. The previous codes begin with calibration in air in terms of air kerma, then use theoretical and generic conversion factors to obtain dose to water that do not take account of chamber-to-chamber variation. Other good reasons for implementing the new codes are that they are conceptually simpler, include improved physical data and improve the consistency for various ionisation chamber types as well as between different beam types. TRS-3982,3 is a new Code of Practice (CoP) for reference dosimetry of external radiotherapy beams based on absorbed dose to, water calibrations and was published by the IAEA in a joint effort with the WHO, PAHO and ESTRO. It is the first CoP of its kind comprehensively covering all external radiotherapy beams except neutrons. The Radiotherapy Interest Group (RJG) of the ACPSEM has recommended that radiotherapy centres in Australia and New Zealand implement this CoP by the end of 2004. In this workshop, the general philosophy of the CoP will be outlined which will provide a framework for each of the individual subcodes. Although it represents just one of the potential implementations of the CoP, this workshop will deal only with dosimetry based on a cylindrical ionisation chamber with an absorbed dose calibration factor in 60Co from the standards laboratory. With the framework of the code in mind, it is straightforward to identify the basic steps that are required for measuring absorbed dose under reference conditions in a high-energy photon beam. The same is true

  16. Technical Report: Reference photon dosimetry data for Varian accelerators based on IROC-Houston site visit data

    Energy Technology Data Exchange (ETDEWEB)

    Kerns, James R.; Followill, David S.; Kry, Stephen F., E-mail: sfkry@mdanderson.org [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Imaging and Radiation Oncology Core-Houston, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Graduate School of Biomedical Sciences, The University of Texas Health Science Center-Houston, Houston, Texas 77030 (United States); Lowenstein, Jessica; Molineu, Andrea; Alvarez, Paola; Taylor, Paige A. [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Imaging and Radiation Oncology Core-Houston, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Stingo, Francesco C. [Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States)

    2016-05-15

    Purpose: Accurate data regarding linear accelerator (Linac) radiation characteristics are important for treatment planning system modeling as well as regular quality assurance of the machine. The Imaging and Radiation Oncology Core-Houston (IROC-H) has measured the dosimetric characteristics of numerous machines through their on-site dosimetry review protocols. Photon data are presented and can be used as a secondary check of acquired values, as a means to verify commissioning a new machine, or in preparation for an IROC-H site visit. Methods: Photon data from IROC-H on-site reviews from 2000 to 2014 were compiled and analyzed. Specifically, data from approximately 500 Varian machines were analyzed. Each dataset consisted of point measurements of several dosimetric parameters at various locations in a water phantom to assess the percentage depth dose, jaw output factors, multileaf collimator small field output factors, off-axis factors, and wedge factors. The data were analyzed by energy and parameter, with similarly performing machine models being assimilated into classes. Common statistical metrics are presented for each machine class. Measurement data were compared against other reference data where applicable. Results: Distributions of the parameter data were shown to be robust and derive from a student’s t distribution. Based on statistical and clinical criteria, all machine models were able to be classified into two or three classes for each energy, except for 6 MV for which there were eight classes. Quantitative analysis of the measurements for 6, 10, 15, and 18 MV photon beams is presented for each parameter; supplementary material has also been made available which contains further statistical information. Conclusions: IROC-H has collected numerous data on Varian Linacs and the results of photon measurements from the past 15 years are presented. The data can be used as a comparison check of a physicist’s acquired values. Acquired values that are well

  17. Technical Report: Reference photon dosimetry data for Varian accelerators based on IROC-Houston site visit data

    International Nuclear Information System (INIS)

    Kerns, James R.; Followill, David S.; Kry, Stephen F.; Lowenstein, Jessica; Molineu, Andrea; Alvarez, Paola; Taylor, Paige A.; Stingo, Francesco C.

    2016-01-01

    Purpose: Accurate data regarding linear accelerator (Linac) radiation characteristics are important for treatment planning system modeling as well as regular quality assurance of the machine. The Imaging and Radiation Oncology Core-Houston (IROC-H) has measured the dosimetric characteristics of numerous machines through their on-site dosimetry review protocols. Photon data are presented and can be used as a secondary check of acquired values, as a means to verify commissioning a new machine, or in preparation for an IROC-H site visit. Methods: Photon data from IROC-H on-site reviews from 2000 to 2014 were compiled and analyzed. Specifically, data from approximately 500 Varian machines were analyzed. Each dataset consisted of point measurements of several dosimetric parameters at various locations in a water phantom to assess the percentage depth dose, jaw output factors, multileaf collimator small field output factors, off-axis factors, and wedge factors. The data were analyzed by energy and parameter, with similarly performing machine models being assimilated into classes. Common statistical metrics are presented for each machine class. Measurement data were compared against other reference data where applicable. Results: Distributions of the parameter data were shown to be robust and derive from a student’s t distribution. Based on statistical and clinical criteria, all machine models were able to be classified into two or three classes for each energy, except for 6 MV for which there were eight classes. Quantitative analysis of the measurements for 6, 10, 15, and 18 MV photon beams is presented for each parameter; supplementary material has also been made available which contains further statistical information. Conclusions: IROC-H has collected numerous data on Varian Linacs and the results of photon measurements from the past 15 years are presented. The data can be used as a comparison check of a physicist’s acquired values. Acquired values that are well

  18. TU-D-201-03: Results of a Survey On the Implementation of the TG-51 Protocol and Associated Addendum On Reference Dosimetry of External Beams

    Energy Technology Data Exchange (ETDEWEB)

    Kim, G [University of California, San Diego, La Jolla, CA (United States); Muir, B [National Research Council, Ottawa, AB (Canada); Culberson, W [University of Wisconsin Madison, Madison, WI (United States); Davis, S [McGill University Health Center, Montreal, QC (Canada); Huang, Y [Henry Ford Health System, West Bloomfield, MI (United States); Lee, S [University of Maryland School of Medicine, Columbia, MD (United States); Lowenstein, J [UT MD Anderson Cancer Center, Houston, TX (United States); Sarfehnia, A [Sunnybrook Health Science Center, Toronto, ON (Canada); Tolani, N [Michael E. DeBakey VA Medical Center, Sugarland (United States); Siebers, J [University of Virginia Health System, Charlottesville, VA (United States)

    2016-06-15

    Purpose: The working group on the review and extension of the TG-51 protocol (WGTG51) collected data from American Association of Physicists in Medicine (AAPM) members with respect to their current TG-51 and associated addendum usage in the interest of considering future protocol addenda and guidance on reference dosimetry best practices. This study reports an overview of this survey on dosimetry of external beams. Methods: Fourteen survey questions were developed by WGTG51 and released in November 2015. The questions collected information on reference dosimetry, beam quality specification, and ancillary calibration equipment. Results: Of the 190 submissions completed worldwide (U.S. 70%), 83% were AAPM members. Of the respondents, 33.5% implemented the TG-51 addendum, with the maximum calibration difference for any photon beam, with respect to the original TG-51 protocol, being <1% for 97.4% of responses. One major finding is that 81.8% of respondents used the same cylindrical ionization chamber for photon and electron dosimetry, implying that many clinics are foregoing the use of parallel-plate chambers. Other evidence suggests equivalent dosimetric results can be obtained with both cylindrical and parallel-plate chambers in electron beams. This, combined with users comfort with cylindrical chambers for electrons will likely impact recommendations put forward in an upcoming electron beam addendum to the TG-51 protocol. Data collected on ancillary equipment showed 58.2% (45.0%) of the thermometers (barometers) in use for beam calibration had NIST traceable calibration certificates, but 48.4% (42.7%) were never recalibrated. Conclusion: This survey provides a snapshot of TG-51 external beam reference dosimetry practice in radiotherapy centers. Findings demonstrate the rapid take-up of the TG-51 photon beam addendum and raise issues for the WGTG51 to focus on going forward, including guidelines on ancillary equipment and the choice of chamber for electron beam

  19. Dosimetry of internal emitters - quo vadis?

    International Nuclear Information System (INIS)

    Reddy, A.R.; Nagaratnam, A.; Jain, S.C.; Gupta, M.M.; Mehta, S.C.

    1999-01-01

    The dosimetry of internally administered radiopharmaceuticals in nuclear medicine procedures using MIRD formalisms and dosimetry in the case of intakes of radionuclides and ICRP methodology for the purpose of radiological protection are well established working practices. It should, however, be remembered that dose or dose coefficients calculated refer to a reference individual, defined in terms of a mathematical phantom established on the basis of certain biokinetic reference parameters. The reference individual represents a typical caucasian adult of West Europe or North American origin. Recently, some attempts have been made to define a Reference Asian and a Reference Indian individual and to assess the effects of anatomical differences and changes in the biokinetics of radiopharmaceuticals and other radionuclides in these different reference individuals on the estimation of dose and dose coefficients in relation to the intake of internal radionuclides. The assessment of doses to the embryo/fetus due to intake of radionuclides by pregnant women, local dose estimates, microdosimetry, radiobiology and radiation protection aspects relating to Auger electron emitters represent other areas of active research in the area of dosimetry of internal emitters. The present review summarises these different aspects of work. (orig.) [de

  20. Reference dosimetry data and modeling challenges for Elekta accelerators based on IROC-Houston site visit data.

    Science.gov (United States)

    Kerns, James R; Followill, David S; Lowenstein, Jessica; Molineu, Andrea; Alvarez, Paola; Taylor, Paige A; Kry, Stephen F

    2018-03-14

    Reference dosimetry data can provide an independent second check of acquired values when commissioning or validating a treatment planning system (TPS). The Imaging and Radiation Oncology Core at Houston (IROC-Houston) has measured numerous linear accelerators throughout its existence. The results of those measurements are given here, comparing accelerators and the agreement of measurement versus institutional TPS calculations. Data from IROC-Houston on-site reviews from 2000 through 2014 were analyzed for all Elekta accelerators, approximately 50. For each, consistent point dose measurements were conducted for several basic parameters in a water phantom, including percentage depth dose, output factors, small-field output factors, off-axis factors, and wedge factors. The results were compared by accelerator type independently for 6, 10, 15, and 18 MV. Distributions of the measurements for each parameter are given, providing the mean and standard deviation. Each accelerator's measurements were also compared to its corresponding TPS calculation from the institution to determine the level of agreement, as well as determining which dosimetric parameters were most often in error. Accelerators were grouped by head type and reference dosimetric values were compiled. No class of linac had better overall agreement with its TPS, but percentage depth dose and output factors commonly agreed well, while small-field output factors, off-axis factors, and wedge factors often disagreed substantially from their TPS calculations. Reference data has been collected and analyzed for numerous Elekta linacs, which provide an independent way for a physicist to double-check their own measurements to prevent gross treatment errors. In addition, treatment planning parameters more often in error have been highlighted, providing practical caution for physicists commissioning treatment planning systems for Elekta linacs. © 2018 American Association of Physicists in Medicine.

  1. Whole-body voxel-based personalized dosimetry: Multiple voxel S-value approach for heterogeneous media with non-uniform activity distributions.

    Science.gov (United States)

    Lee, Min Sun; Kim, Joong Hyun; Paeng, Jin Chul; Kang, Keon Wook; Jeong, Jae Min; Lee, Dong Soo; Lee, Jae Sung

    2017-12-14

    Personalized dosimetry with high accuracy is becoming more important because of the growing interests in personalized medicine and targeted radionuclide therapy. Voxel-based dosimetry using dose point kernel or voxel S-value (VSV) convolution is available. However, these approaches do not consider medium heterogeneity. Here, we propose a new method for whole-body voxel-based personalized dosimetry for heterogeneous media with non-uniform activity distributions, which is referred to as the multiple VSV approach. Methods: The multiple numbers (N) of VSVs for media with different densities covering the whole-body density ranges were used instead of using only a single VSV for water. The VSVs were pre-calculated using GATE Monte Carlo simulation; those were convoluted with the time-integrated activity to generate density-specific dose maps. Computed tomography-based segmentation was conducted to generate binary maps for each density region. The final dose map was acquired by the summation of N segmented density-specific dose maps. We tested several sets of VSVs with different densities: N = 1 (single water VSV), 4, 6, 8, 10, and 20. To validate the proposed method, phantom and patient studies were conducted and compared with direct Monte Carlo, which was considered the ground truth. Finally, patient dosimetry (10 subjects) was conducted using the multiple VSV approach and compared with the single VSV and organ-based dosimetry approaches. Errors at the voxel- and organ-levels were reported for eight organs. Results: In the phantom and patient studies, the multiple VSV approach showed significant improvements regarding voxel-level errors, especially for the lung and bone regions. As N increased, voxel-level errors decreased, although some overestimations were observed at lung boundaries. In the case of multiple VSVs ( N = 8), we achieved voxel-level errors of 2.06%. In the dosimetry study, our proposed method showed much improved results compared to the single VSV and

  2. Reference dosimeter system of the IAEA

    International Nuclear Information System (INIS)

    Mehta, Kishor; Girzikowsky, Reinhard

    1995-01-01

    Quality assurance programmes must be in operation at radiation facilities to satisfy national and international Standards. Since dosimetry has a vital function in these QA programmes, it is imperative that the dosimetry systems in use at these facilities are well calibrated with a traceability to a Primary Standard Dosimetry Laboratory. As a service to the Member States, the International Atomic Energy Agency operates the International Dose Assurance Service (IDAS) to assist in this process. The transfer standard dosimetry system that is used for this service is based on ESR spectrometry. The paper describes the activities undertaken at the IAEA Dosimetry Laboratory to establish the QA programme for its reference dosimetry system. There are four key elements of such a programme: quality assurance manual; calibration that is traceable to a Primary Standard Dosimetry Laboratory; a clear and detailed statement of uncertainty in the dose measurement; and, periodic quality audit. (Author)

  3. Reference dosimeter system of the iaea

    Science.gov (United States)

    Mehta, Kishor; Girzikowsky, Reinhard

    1995-09-01

    Quality assurance programmes must be in operation at radiation processing facilities to satisfy national and international Standards. Since dosimetry has a vital function in these QA programmes, it is imperative that the dosimetry systems in use at these facilities are well calibrated with a traceability to a Primary Standard Dosimetry Laboratory. As a service to the Member States, the International Atomic Energy Agency operates the International Dose Assurance Service (IDAS) to assist in this process. The transfer standard dosimetry system that is used for this service is based on ESR spectrometry. The paper describes the activities undertaken at the IAEA Dosimetry Laboratory to establish the QA programme for its reference dosimetry system. There are four key elements of such a programme: quality assurance manual; calibration that is traceable to a Primary Standard Dosimetry Laboratory; a clear and detailed statement of uncertainty in the dose measurement; and, periodic quality audit.

  4. Reference dosimeter system of the IAEA

    International Nuclear Information System (INIS)

    Mehta, K.; Girzikowsky, R.

    1995-01-01

    Quality assurance programmes must be in operation at radiation processing facilities to satisfy national and international standards. Since dosimetry has a vital function in these QA programmes, it is imperative that the dosimetry systems in use at these facilities are well calibrated with a traceability to a Primary Standard Dosimetry Laboratory. As a service to the Member States, the International Atomic Energy Agency operates the International Dose Assurance Service (IDAS) to assist in this process. The transfer standard dosimetry system that is used for this service is based on ESR spectrometry. The paper describes the activities undertaken at the IAEA Dosimetry Laboratory to establish the QA programme for its reference dosimetry system. There are four key elements of such a programme: quality assurance manual; calibration that is traceable to a Primary Standard Dosimetry Laboratory; a clear and detailed statement of uncertainty in the dose measurement; and, periodic quality audit. (author)

  5. The UF family of reference hybrid phantoms for computational radiation dosimetry

    International Nuclear Information System (INIS)

    Lee, Choonsik; Lodwick, Daniel; Hurtado, Jorge; Pafundi, Deanna; Williams, Jonathan L; Bolch, Wesley E

    2010-01-01

    Computational human phantoms are computer models used to obtain dose distributions within the human body exposed to internal or external radiation sources. In addition, they are increasingly used to develop detector efficiencies for in vivo whole-body counters. Two classes of computational human phantoms have been widely utilized for dosimetry calculation: stylized and voxel phantoms that describe human anatomy through mathematical surface equations and 3D voxel matrices, respectively. Stylized phantoms are flexible in that changes to organ position and shape are possible given avoidance of region overlap, while voxel phantoms are typically fixed to a given patient anatomy, yet can be proportionally scaled to match individuals of larger or smaller stature, but of equivalent organ anatomy. Voxel phantoms provide much better anatomical realism as compared to stylized phantoms which are intrinsically limited by mathematical surface equations. To address the drawbacks of these phantoms, hybrid phantoms based on non-uniform rational B-spline (NURBS) surfaces have been introduced wherein anthropomorphic flexibility and anatomic realism are both preserved. Researchers at the University of Florida have introduced a series of hybrid phantoms representing the ICRP Publication 89 reference newborn, 15 year, and adult male and female. In this study, six additional phantoms are added to the UF family of hybrid phantoms-those of the reference 1 year, 5 year and 10 year child. Head and torso CT images of patients whose ages were close to the targeted ages were obtained under approved protocols. Major organs and tissues were segmented from these images using an image processing software, 3D-DOCTOR(TM). NURBS and polygon mesh surfaces were then used to model individual organs and tissues after importing the segmented organ models to the 3D NURBS modeling software, Rhinoceros(TM). The phantoms were matched to four reference datasets: (1) standard anthropometric data, (2) reference

  6. Consequences of air around an ionization chamber : Are existing solid phantoms suitable for reference dosimetry on an MR-linac?

    NARCIS (Netherlands)

    Hackett, S. L.; Van Asselen, B.; Wolthaus, J. W H; Kok, J. G M; Woodings, S. J.; Lagendijk, J. J W; Raaymakers, B. W.

    2016-01-01

    Purpose: A protocol for reference dosimetry for the MR-linac is under development. The 1.5 T magnetic field changes the mean path length of electrons in an air-filled ionization chamber but has little effect on the electron trajectories in a surrounding phantom. It is therefore necessary to correct

  7. WE-H-207A-07: Image-Based Versus Atlas-Based Internal Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Fallahpoor, M; Abbasi, M [Vali-Asr Hospital, School of Medicine, Tehran University of Medical Science, Tehran, Tehran (Iran, Islamic Republic of); Parach, A [Shahid Sadoughi University of Medical Sciences, Yazd, Yazd (Iran, Islamic Republic of); Kalantari, F [UT Southwestern Medical Center, Dallas, TX (United States)

    2016-06-15

    Purpose: Monte Carlo (MC) simulation is known as the gold standard method for internal dosimetry. It requires radionuclide distribution from PET or SPECT and body structure from CT for accurate dose calculation. The manual or semi-automatic segmentation of organs from CT images is a major obstacle. The aim of this study is to compare the dosimetry results based on patient’s own CT and a digital humanoid phantom as an atlas with pre-specified organs. Methods: SPECT-CT images of a 50 year old woman who underwent bone pain palliation with Samarium-153 EDTMP for osseous metastases from breast cancer were used. The anatomical date and attenuation map were extracted from SPECT/CT and three XCAT digital phantoms with different BMIs (i.e. matched (38.8) and unmatched (35.5 and 36.7) with patient’s BMI that was 38.3). Segmentation of patient’s organs in CT image was performed using itk-SNAP software. GATE MC Simulator was used for dose calculation. Specific absorbed fractions (SAFs) and S-values were calculated for the segmented organs. Results: The differences between SAFs and S-values are high using different anatomical data and range from −13% to 39% for SAF values and −109% to 79% for S-values in different organs. In the spine, the clinically important target organ for Samarium Therapy, the differences in the S-values and SAF values are higher between XCAT phantom and CT when the phantom with identical BMI is employed (53.8% relative difference in S-value and 26.8% difference in SAF). However, the whole body dose values were the same between the calculations based on the CT and XCAT with different BMIs. Conclusion: The results indicated that atlas-based dosimetry using XCAT phantom even with matched BMI for patient leads to considerable errors as compared to image-based dosimetry that uses the patient’s own CT Patient-specific dosimetry using CT image is essential for accurate results.

  8. Use of national metrological references of dose absorbed in water and application of the IAEA TRS nr 398 dosimetry protocol to high energy photon beams. BNM-LNHB-LCIE-SFPM working group

    International Nuclear Information System (INIS)

    Chauvenet, B.; Delaunay, F.; Dolo, J.M.; Le Roy, G.; Bridier, A.; Francois, P.; Sabattier, R.

    2003-01-01

    Metrological references of dose absorbed in water for high energy photon beams used in radiotherapy have been elaborated during the past years by national calibration laboratories, and these new references are the basis of recent dosimetry protocols. However, the passage from metrological references of air kerma to dose absorbed in water, as well as the practical application of new calibration opportunities for dosemeters in high energy X ray beams requires a specific attention to maintain the consistency of dose measurement references over the hospital site. In this respect, this guide aims at the application of these metrological references. It proposes recommendations for the application of metrological references in terms of dose absorbed in water on the hospital site with reference to their determination conditions and to the implementation of the new IAEA dosimetry protocol (TRS nr 398). Thus, this guide proposes an overview of metrological references in French calibration laboratories, presents calibration methods (air kerma in a cobalt 60 gamma photon beam, dose absorbed in water) and a comparison with the IAEA TRS 277 dosimetry protocol. It addresses various practical aspects, and discusses uncertainties

  9. Dosimetry system 1986

    International Nuclear Information System (INIS)

    Woolson, William A.; Egbert, Stephen D.; Gritzner, Michael L.

    1987-01-01

    In May 1983, the authors proposed a dosimetry system for use by the Radiation Effects Research Foundation (RERF) that would incorporate the new findings and calculations of the joint United States - Japan working groups on the reassessment of A-bomb dosimetry. The proposed dosimetry system evolved from extensive discussions with RERF personnel, numerous meetings of the scientists from Japan and the United States involved in the dosimetry reassessment research, and requirements expressed by epidemiologists and radiobiologists on the various review panels. The dosimetry system proposed was based on considerations of the dosimetry requirements for the normal work of RERF and for future research in radiobiology, the computerized input data on A-bomb survivors available in the RERF data base, the level of detail, precision, and accuracy of various components of the dosimetric estimates, and the computer resources available at RERF in Hiroshima. These discussions and our own experience indicated that, in light of the expansion of computer and radiation technologies and the desire for more detail in the dosimetry, an entirely new approach to the dosimetry system was appropriate. This resulted in a complete replacement of the T65D system as distinguished from a simpler approach involving a renormalization of T65D parameters to reflect the new dosimetry. The proposed dosimetry system for RERF and the plan for implementation was accepted by the Department of Energy (DOE) Working Group on A-bomb Dosimetry chaired by Dr. R.F. Christy. The dosimetry system plan was also presented to the binational A-bomb dosimetry review groups for critical comment and was discussed at joint US-Japan workshop. A prototype dosimetry system incorporating preliminary dosimetry estimates and applicable to only a limited set of A-bomb survivors was installed on the RERF computer system in the fall of 1984. This system was successfully operated at RERF and provided an initial look at the impact of

  10. ALGEBRA: ALgorithm for the heterogeneous dosimetry based on GEANT4 for BRAchytherapy.

    Science.gov (United States)

    Afsharpour, H; Landry, G; D'Amours, M; Enger, S; Reniers, B; Poon, E; Carrier, J-F; Verhaegen, F; Beaulieu, L

    2012-06-07

    Task group 43 (TG43)-based dosimetry algorithms are efficient for brachytherapy dose calculation in water. However, human tissues have chemical compositions and densities different than water. Moreover, the mutual shielding effect of seeds on each other (interseed attenuation) is neglected in the TG43-based dosimetry platforms. The scientific community has expressed the need for an accurate dosimetry platform in brachytherapy. The purpose of this paper is to present ALGEBRA, a Monte Carlo platform for dosimetry in brachytherapy which is sufficiently fast and accurate for clinical and research purposes. ALGEBRA is based on the GEANT4 Monte Carlo code and is capable of handling the DICOM RT standard to recreate a virtual model of the treated site. Here, the performance of ALGEBRA is presented for the special case of LDR brachytherapy in permanent prostate and breast seed implants. However, the algorithm is also capable of handling other treatments such as HDR brachytherapy.

  11. Monte Carlo computed machine-specific correction factors for reference dosimetry of TomoTherapy static beam for several ion chambers

    International Nuclear Information System (INIS)

    Sterpin, E.; Mackie, T. R.; Vynckier, S.

    2012-01-01

    Purpose: To determine k Q msr ,Q o f msr ,f o correction factors for machine-specific reference (msr) conditions by Monte Carlo (MC) simulations for reference dosimetry of TomoTherapy static beams for ion chambers Exradin A1SL, A12; PTW 30006, 31010 Semiflex, 31014 PinPoint, 31018 microLion; NE 2571. Methods: For the calibration of TomoTherapy units, reference conditions specified in current codes of practice like IAEA/TRS-398 and AAPM/TG-51 cannot be realized. To cope with this issue, Alfonso et al. [Med. Phys. 35, 5179–5186 (2008)] described a new formalism introducing msr factors k Q msr ,Q o f msr ,f o for reference dosimetry, applicable to static TomoTherapy beams. In this study, those factors were computed directly using MC simulations for Q 0 corresponding to a simplified 60 Co beam in TRS-398 reference conditions (at 10 cm depth). The msr conditions were a 10 × 5 cm 2 TomoTherapy beam, source-surface distance of 85 cm and 10 cm depth. The chambers were modeled according to technical drawings using the egs++ package and the MC simulations were run with the egs c hamber user code. Phase-space files used as the source input were produced using PENELOPE after simulation of a simplified 60 Co beam and the TomoTherapy treatment head modeled according to technical drawings. Correlated sampling, intermediate phase-space storage, and photon cross-section enhancement variance reduction techniques were used. The simulations were stopped when the combined standard uncertainty was below 0.2%. Results: Computed k Q msr ,Q o f msr ,f o values were all close to one, in a range from 0.991 for the PinPoint chamber to 1.000 for the Exradin A12 with a statistical uncertainty below 0.2%. Considering a beam quality Q defined as the TPR 20,10 for a 6 MV Elekta photon beam (0.661), the additional correction k Q msr, Q f msr, f ref to k Q,Q o defined in Alfonso et al. [Med. Phys. 35, 5179–5186 (2008)] formalism was in a range from 0.997 to 1.004.Conclusion: The MC computed

  12. Is the PTW 60019 microDiamond a suitable candidate for small field reference dosimetry?

    Science.gov (United States)

    De Coste, Vanessa; Francescon, Paolo; Marinelli, Marco; Masi, Laura; Paganini, Lucia; Pimpinella, Maria; Prestopino, Giuseppe; Russo, Serenella; Stravato, Antonella; Verona, Claudio; Verona-Rinati, Gianluca

    2017-09-01

    A systematic study of the PTW microDiamond (MD) output factors (OF) is reported, aimed at clarifying its response in small fields and investigating its suitability for small field reference dosimetry. Ten MDs were calibrated under 60Co irradiation. OF measurements were performed in 6 MV photon beams by a CyberKnife M6, a Varian DHX and an Elekta Synergy linacs. Two PTW silicon diodes E (Si-D) were used for comparison. The results obtained by the MDs were evaluated in terms of absorbed dose to water determination in reference conditions and OF measurements, and compared to the results reported in the recent literature. To this purpose, the Monte Carlo (MC) beam-quality correction factor, kQMD , was calculated for the MD, and the small field output correction factors, k{{Qclin},{{Q}msr}}{{fclin},{{f}msr}} , were calculated for both the MD and the Si-D by two different research groups. An empirical function was also derived, providing output correction factors within 0.5% from the MC values calculated for all of the three linacs. A high reproducibility of the dosimetric properties was observed among the ten MDs. The experimental kQMD values are in agreement within 1% with the MC calculated ones. Output correction factors within  +0.7% and  -1.4% were obtained down to field sizes as narrow as 5 mm. The resulting MD and Si-D field factors are in agreement within 0.2% in the case of CyberKnife measurements and 1.6% in the other cases. This latter higher spread of the data was demonstrated to be due to a lower reproducibility of small beam sizes defined by jaws or multi leaf collimators. The results of the present study demonstrate the reproducibility of the MD response and provide a validation of the MC modelling of this device. In principle, accurate reference dosimetry is thus feasible by using the microDiamond dosimeter for field sizes down to 5 mm.

  13. TestDose: A nuclear medicine software based on Monte Carlo modeling for generating gamma camera acquisitions and dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, Marie-Paule, E-mail: marie-paule.garcia@univ-brest.fr; Villoing, Daphnée [UMR 1037 INSERM/UPS, CRCT, 133 Route de Narbonne, 31062 Toulouse (France); McKay, Erin [St George Hospital, Gray Street, Kogarah, New South Wales 2217 (Australia); Ferrer, Ludovic [ICO René Gauducheau, Boulevard Jacques Monod, St Herblain 44805 (France); Cremonesi, Marta; Botta, Francesca; Ferrari, Mahila [European Institute of Oncology, Via Ripamonti 435, Milano 20141 (Italy); Bardiès, Manuel [UMR 1037 INSERM/UPS, CRCT, 133 Route de Narbonne, Toulouse 31062 (France)

    2015-12-15

    Purpose: The TestDose platform was developed to generate scintigraphic imaging protocols and associated dosimetry by Monte Carlo modeling. TestDose is part of a broader project (www.dositest.com) whose aim is to identify the biases induced by different clinical dosimetry protocols. Methods: The TestDose software allows handling the whole pipeline from virtual patient generation to resulting planar and SPECT images and dosimetry calculations. The originality of their approach relies on the implementation of functional segmentation for the anthropomorphic model representing a virtual patient. Two anthropomorphic models are currently available: 4D XCAT and ICRP 110. A pharmacokinetic model describes the biodistribution of a given radiopharmaceutical in each defined compartment at various time-points. The Monte Carlo simulation toolkit GATE offers the possibility to accurately simulate scintigraphic images and absorbed doses in volumes of interest. The TestDose platform relies on GATE to reproduce precisely any imaging protocol and to provide reference dosimetry. For image generation, TestDose stores user’s imaging requirements and generates automatically command files used as input for GATE. Each compartment is simulated only once and the resulting output is weighted using pharmacokinetic data. Resulting compartment projections are aggregated to obtain the final image. For dosimetry computation, emission data are stored in the platform database and relevant GATE input files are generated for the virtual patient model and associated pharmacokinetics. Results: Two samples of software runs are given to demonstrate the potential of TestDose. A clinical imaging protocol for the Octreoscan™ therapeutical treatment was implemented using the 4D XCAT model. Whole-body “step and shoot” acquisitions at different times postinjection and one SPECT acquisition were generated within reasonable computation times. Based on the same Octreoscan™ kinetics, a dosimetry

  14. Status of neutron dosimetry cross sections

    International Nuclear Information System (INIS)

    Griffin, P.J.; Kelly, J.G.

    1992-01-01

    Several new cross section libraries, such as ENDF/B-VI(release 2), IRDF-90,JEF-2.2, and JENDL-3 Dosimetry, have recently been made available to the dosimetry community. the Sandia National Laboratories (SNL) Radiation Metrology Laboratory (RML) has worked with these libraries since pre-release versions were available. this paper summarizes the results of the intercomparison and testing of dosimetry cross sections. As a result of this analysis, a compendium of the best dosimetry cross sections was assembled from the available libraries for use within the SNL RML. this library, referred to as the SNLRML Library, contains 66 general dosimetry sensors and 3 special dosimeters unique to the RML sensor inventory. The SNLRML cross sections have been put into a format compatible with commonly used spectrum determination codes

  15. Development of internal dosimetry protocols using the code MCNPx and voxelized phantoms of Reference of ICRP 110; Desenvolvimento de protocolos de dosimetria interna empregando o codigo MCNPx e fantomas voxelizados de referencia da ICRP 110

    Energy Technology Data Exchange (ETDEWEB)

    Mendes, B.M.; Fonseca, T.C.F., E-mail: bmm@cdtn.br [Centro de esenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Trindade, B.M.; Campos, T.P.R. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear

    2017-04-01

    The objective of this work was to perform internal dosimetry calculations for {sup 18}F-FDG employing the MCNPx code and ICRP 110 voxelized reference phantoms (RCP{sub A}F and RCP{sub A}M). The methodologies developed and validated here represent protocols of internal dosimetry holding a better anthropomorphic and anthropometric representation of the human model in which heterogeneous distributions of the emissions can be adopted, useful in the study of new radiopharmaceuticals and internal contamination cases. The reference phantoms were implemented to run on MCNPx. Biodistribution data of {sup 18}F-FDG radiopharmaceutical provided in ICRP 128 were used in the simulations. The organs average absorbed doses and the effective doses were calculated for each model. The values obtained were compared with two reference works available in the literature for validation purposes. The means of the difference of our values and Zankl et al., 2012 reference values were -0.3% for RCP{sub A}M and -0.4% for RCP{sub A}F. Considering Hadid et al., 2013 reference values, the means of the deviation were -2.9% and -2.2% for RCP{sub A}M and RCP{sub A}F respectively. No statistically significant differences were observed (p <0.01) between the reference values and the values calculated by the internal dosimetry protocols developed by our group. Considering the {sup 18}F-FDG validation study performed in this work, the internal dosimetry protocols developed by our group have produced suitable dosimetry data. (author)

  16. Technical basis for external dosimetry at the Waste Isolation Pilot Plant (WIPP)

    International Nuclear Information System (INIS)

    Bradley, E.W.; Wu, C.F.; Goff, T.E.

    1993-01-01

    The WIPP External Dosimetry Program, administered by Westinghouse Electric Corporation, Waste Isolation Division, for the US Department of Energy (DOE), provides external dosimetry support services for operations at the Waste Isolation Pilot Plant (WIPP) Site. These operations include the receipt, experimentation with, storage, and disposal of transuranic (TRU) wastes. This document describes the technical basis for the WIPP External Radiation Dosimetry Program. The purposes of this document are to: (1) provide assurance that the WIPP External Radiation Dosimetry Program is in compliance with all regulatory requirements, (2) provide assurance that the WIPP External Radiation Dosimetry Program is derived from a sound technical base, (3) serve as a technical reference for radiation protection personnel, and (4) aid in identifying and planning for future needs. The external radiation exposure fields are those that are documented in the WIPP Final Safety Analysis Report

  17. Individual dosimetry of workers and patients: implementation and perspectives; La dosimetrie individuelle des travailleurs et de patients: mise en oeuvre et perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Rannou, A.; Aubert, B.; Lahaye, Th.; Scaff, P.; Casanova, Ph.; Van Bladel, L.; Queinnec, F.; Valendru, N.; Jehanno, J.; Grude, E.; Berard, Ph.; Desbree, A.; Kafrouni, H.; Paquet, F.; Vanhavere, F.; Bridier, A.; Ginestet, Ch.; Magne, S.; Donadille, L.; Bordy, J.M.; Bottollier-Depois, J.F.; Barrere, J.L.; Ferragut, A.; Metivier, H.; Gaillard-Lecanu, E

    2008-07-01

    These days organised by the section of the technical protection of the S.F.R.P. review the different techniques of dosimetry used in France and Europe, and present the future orientations.The different interventions are as follow: Individual exposures of the workers: historic assessment and perspectives; medical exposure: where are the doses; legal obligations in individual dosimetry: which are the objective and the need on the subject; the dosimetry follow-up of workers by the S.I.S.E.R.I. system: assessment and perspectives; impact of the norm ISO 20553 on the follow-up of internal exposure; the implementation of the patient dose measurement in Belgium; techniques of passive dosimetry used in Europe; Supervision radiation protection at EDF: long term and short term approach; Comparison active and passive dosimetry at Melox; methodology for the choice of new neutron dosemeters; the working group M.E.D.O.R.: guide of internal dosimetry for the use of practitioners; O.E.D.I.P.E.: tool of modeling for the personalized internal dosimetry; the use of the Monte-Carlo method for the planning of the cancer treatment by radiotherapy becomes a reality; the works of the committee 2 of the ICRP; passive dosimetry versus operational dosimetry: situation in Europe; Implementation of the in vivo dosimetry in a radiotherapy department: experience of the Gustave Roussy institute; experience feedback on the in vivo measures in radiotherapy, based on the use of O.S.L. pellets; multi points O.S.L. instrumentation for the radiation dose monitoring in radiotherapy; dosimetry for extremities for medical applications: principle results of the European contract C.O.N.R.A.D.; references and perspectives in dosimetry; what perspectives for numerical dosimetry, an example: Sievert; system of dose management: how to answer to needs; the last technical evolutions in terms of electronic dosimetry in nuclear power plant; the fourth generation type reactors: what dosimetry. (N.C.)

  18. Accuracy Requirements in Medical Radiation Dosimetry

    International Nuclear Information System (INIS)

    Andreo, P.

    2011-01-01

    The need for adopting unambiguous terminology on 'accuracy in medical radiation dosimetry' which is consistent with international recommendations for metrology is emphasized. Uncertainties attainable, or the need for improving their estimates, are analysed for the fields of radiotherapy, diagnostic radiology and nuclear medicine dosimetry. This review centres on uncertainties related to the first step of the dosimetry chain in the three fields, which in all cases involves the use of a detector calibrated by a standards laboratory to determine absorbed dose, air kerma or activity under reference conditions in a clinical environment. (author)

  19. Results from 2010 Caliban Criticality Dosimetry Intercomparison

    Energy Technology Data Exchange (ETDEWEB)

    Veinot, K. G.

    2011-10-12

    The external dosimetry program participated in a criticality dosimetry intercomparison conducted at the Caliban facility in Valduc, France in 2010. Representatives from the dosimetry and instrumentation groups were present during testing which included irradiations of whole-body beta/gamma (HBGT) and neutron thermoluminescent dosimeters (TLDs), a fixed nuclear accident dosimeter (FNAD), electronic alarming dosimeters, and a humanoid phantom filled with reference man concentrations of sodium. This report reviews the testing procedures, preparations, irradiations, and presents results of the tests.

  20. SU-F-T-562: Validation of EPID-Based Dosimetry for FSRS Commissioning

    International Nuclear Information System (INIS)

    Song, Y; Saleh, Z; Obcemea, C; Chan, M; Tang, X; Lim, S; Lovelock, D; Ballangrud, A; Mueller, B; Zinovoy, M; Gelblum, D; Mychalczak, B; Both, S

    2016-01-01

    Purpose: The prevailing approach to frameless SRS (fSRS) small field dosimetry is Gafchromic film. Though providing continuous information, its intrinsic uncertainties in fabrication, response, scan, and calibration often make film dosimetry subject to different interpretations. In this study, we explored the feasibility of using EPID portal dosimetry as a viable alternative to film for small field dosimetry. Methods: Plans prescribed a dose of 21 Gy were created on a flat solid water phantom with Eclipse V11 and iPlan for small static square fields (1.0 to 3.0 cm). In addition, two clinical test plans were computed by employing iPlan on a CIRS Kesler head phantom for target dimensions of 1.2cm and 2.0cm. Corresponding portal dosimetry plans were computed using the Eclipse TPS and delivered on a Varian TrueBeam machine. EBT-XD film dosimetry was performed as a reference. The isocenter doses were measured using EPID, OSLD, stereotactic diode, and CC01 ion chamber. Results: EPID doses at the center of the square field were higher than Eclipse TPS predicted portal doses, with the mean difference being 2.42±0.65%. Doses measured by EBT-XD film, OSLD, stereotactic diode, and CC01 ion chamber revealed smaller differences (except OSLDs), with mean differences being 0.36±3.11%, 4.12±4.13%, 1.7±2.76%, 1.45±2.37% for Eclipse and −1.36±0.85%, 2.38±4.2%, −0.03±0.50%, −0.27±0.78% for iPlan. The profiles measured by EPID and EBT-XD film resembled TPS (Eclipse and iPlan) predicted ones within 3.0%. For the two clinical test plans, the EPID mean doses at the center of field were 2.66±0.68% and 2.33±0.32% higher than TPS predicted doses. Conclusion: We found that results obtained with EPID portal dosimetry were slightly higher (∼2%) than those obtained with EBT-XD film, diode, and CC01 ion chamber with the exception of OSLDs, but well within IROC tolerance (5.0%). Therefore, EPID has the potential to become a viable real-time alternative method to film dosimetry.

  1. SU-F-T-562: Validation of EPID-Based Dosimetry for FSRS Commissioning

    Energy Technology Data Exchange (ETDEWEB)

    Song, Y; Saleh, Z; Obcemea, C; Chan, M; Tang, X; Lim, S; Lovelock, D; Ballangrud, A; Mueller, B; Zinovoy, M; Gelblum, D; Mychalczak, B; Both, S [Memorial Sloan Kettering Cancer Center, NY (United States)

    2016-06-15

    Purpose: The prevailing approach to frameless SRS (fSRS) small field dosimetry is Gafchromic film. Though providing continuous information, its intrinsic uncertainties in fabrication, response, scan, and calibration often make film dosimetry subject to different interpretations. In this study, we explored the feasibility of using EPID portal dosimetry as a viable alternative to film for small field dosimetry. Methods: Plans prescribed a dose of 21 Gy were created on a flat solid water phantom with Eclipse V11 and iPlan for small static square fields (1.0 to 3.0 cm). In addition, two clinical test plans were computed by employing iPlan on a CIRS Kesler head phantom for target dimensions of 1.2cm and 2.0cm. Corresponding portal dosimetry plans were computed using the Eclipse TPS and delivered on a Varian TrueBeam machine. EBT-XD film dosimetry was performed as a reference. The isocenter doses were measured using EPID, OSLD, stereotactic diode, and CC01 ion chamber. Results: EPID doses at the center of the square field were higher than Eclipse TPS predicted portal doses, with the mean difference being 2.42±0.65%. Doses measured by EBT-XD film, OSLD, stereotactic diode, and CC01 ion chamber revealed smaller differences (except OSLDs), with mean differences being 0.36±3.11%, 4.12±4.13%, 1.7±2.76%, 1.45±2.37% for Eclipse and −1.36±0.85%, 2.38±4.2%, −0.03±0.50%, −0.27±0.78% for iPlan. The profiles measured by EPID and EBT-XD film resembled TPS (Eclipse and iPlan) predicted ones within 3.0%. For the two clinical test plans, the EPID mean doses at the center of field were 2.66±0.68% and 2.33±0.32% higher than TPS predicted doses. Conclusion: We found that results obtained with EPID portal dosimetry were slightly higher (∼2%) than those obtained with EBT-XD film, diode, and CC01 ion chamber with the exception of OSLDs, but well within IROC tolerance (5.0%). Therefore, EPID has the potential to become a viable real-time alternative method to film dosimetry.

  2. Individual dosimetry of workers and patients: implementation and perspectives

    International Nuclear Information System (INIS)

    Rannou, A.; Aubert, B.; Lahaye, Th.; Scaff, P.; Casanova, Ph.; Van Bladel, L.; Queinnec, F.; Valendru, N.; Jehanno, J.; Grude, E.; Berard, Ph.; Desbree, A.; Kafrouni, H.; Paquet, F.; Vanhavere, F.; Bridier, A.; Ginestet, Ch.; Magne, S.; Donadille, L.; Bordy, J.M.; Bottollier-Depois, J.F.; Barrere, J.L.; Ferragut, A.; Metivier, H.; Gaillard-Lecanu, E.

    2008-01-01

    These days organised by the section of the technical protection of the S.F.R.P. review the different techniques of dosimetry used in France and Europe, and present the future orientations.The different interventions are as follow: Individual exposures of the workers: historic assessment and perspectives; medical exposure: where are the doses; legal obligations in individual dosimetry: which are the objective and the need on the subject; the dosimetry follow-up of workers by the S.I.S.E.R.I. system: assessment and perspectives; impact of the norm ISO 20553 on the follow-up of internal exposure; the implementation of the patient dose measurement in Belgium; techniques of passive dosimetry used in Europe; Supervision radiation protection at EDF: long term and short term approach; Comparison active and passive dosimetry at Melox; methodology for the choice of new neutron dosemeters; the working group M.E.D.O.R.: guide of internal dosimetry for the use of practitioners; O.E.D.I.P.E.: tool of modeling for the personalized internal dosimetry; the use of the Monte-Carlo method for the planning of the cancer treatment by radiotherapy becomes a reality; the works of the committee 2 of the ICRP; passive dosimetry versus operational dosimetry: situation in Europe; Implementation of the in vivo dosimetry in a radiotherapy department: experience of the Gustave Roussy institute; experience feedback on the in vivo measures in radiotherapy, based on the use of O.S.L. pellets; multi points O.S.L. instrumentation for the radiation dose monitoring in radiotherapy; dosimetry for extremities for medical applications: principle results of the European contract C.O.N.R.A.D.; references and perspectives in dosimetry; what perspectives for numerical dosimetry, an example: Sievert; system of dose management: how to answer to needs; the last technical evolutions in terms of electronic dosimetry in nuclear power plant; the fourth generation type reactors: what dosimetry. (N.C.)

  3. Advances in kilovoltage x-ray beam dosimetry

    Science.gov (United States)

    Hill, Robin; Healy, Brendan; Holloway, Lois; Kuncic, Zdenka; Thwaites, David; Baldock, Clive

    2014-03-01

    This topical review provides an up-to-date overview of the theoretical and practical aspects of therapeutic kilovoltage x-ray beam dosimetry. Kilovoltage x-ray beams have the property that the maximum dose occurs very close to the surface and thus, they are predominantly used in the treatment of skin cancers but also have applications for the treatment of other cancers. In addition, kilovoltage x-ray beams are used in intra operative units, within animal irradiators and in on-board imagers on linear accelerators and kilovoltage dosimetry is important in these applications as well. This review covers both reference and relative dosimetry of kilovoltage x-ray beams and provides recommendations for clinical measurements based on the literature to date. In particular, practical aspects for the selection of dosimeter and phantom material are reviewed to provide suitable advice for medical physicists. An overview is also presented of dosimeters other than ionization chambers which can be used for both relative and in vivo dosimetry. Finally, issues related to the treatment planning and the use of Monte Carlo codes for solving radiation transport problems in kilovoltage x-ray beams are presented.

  4. Dosimetry

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    The purpose of ionizing radiation dosimetry is the measurement of the physical and biological consequences of exposure to radiation. As these consequences are proportional to the local absorption of energy, the dosimetry of ionizing radiation is based on the measurement of this quantity. Owing to the size of the effects of ionizing radiation on materials in all of these area, dosimetry plays an essential role in the prevention and the control of radiation exposure. Its use is of great importance in two areas in particular where the employment of ionizing radiation relates to human health: radiation protection, and medical applications. Dosimetry is different for various reasons: owing to the diversity of the physical characteristics produced by different kinds of radiation according to their nature (X- and γ-photons, electrons, neutrons,...), their energy (from several keV to several MeV), the orders of magnitude of the doses being estimated (a factor of about 10 5 between diagnostic and therapeutic applications); and the temporal and spatial variation of the biological parameters entering into the calculations. On the practical level, dosimetry poses two distinct yet closely related problems: the determination of the absorbed dose received by a subject exposed to radiation from a source external to his body (external dosimetry); and the determination of the absorbed dose received by a subject owing to the presence within his body of some radioactive substance (internal dosimetry)

  5. Alanine-EPR dosimetry system for high industrial as well radiotherapeutic dose measurement

    International Nuclear Information System (INIS)

    Dobrovodsky, J.; Bukovjan, J.

    2005-01-01

    Slovak Institute of Metrology is developing new metrology standard for high doses, based on the alanine-EPR as a reference dosimetry system. A Bruker e-scan EPR analyser developed specifically for alanine dosimetry has improved stability of EPR measurement, especially at lower dose range. The standard e-scan system provides sensitivity below 1 Gray. After further improvement of the system and lowering of dose determination expanded uncertainty down below 1 %, its utilisation for radiotherapy field is expected (authors)

  6. Argentine intercomparison programme for personal dosimetry

    International Nuclear Information System (INIS)

    Gregori, B.N.; Papadopulos, S.B.; Cruzate, J.; Kunst, J.J.; Saravi, M.

    2005-01-01

    Full text: In 1997 began in Argentine, sponsored by Nuclear Regulatory Authority (ARN) the intercomparison program for personal dosimetry laboratories, on a voluntary basis. Up to know 6 exercises have been done. The program began with a workshop to present the quantities, personal dose equivalent, Hp(10) and extremities dose equivalent, Hs(d). The first aim of this program was to know the true sate of personal dosimetry laboratories in the country, and then introduce the personal dose equivalent, Hp(10) into the dose measurements. The Regional Reference Center for Dosimetry (CCR), belonging to CNEA and the Physical Dosimetry Laboratory of ARN performed the irradiation. Those were done air free and on ICRU phantom, using x-ray, quality ISO: W60, W110 and W200; and 137 Cs and 60 Co gamma rays. The irradiation was made following ISO 4037 (2) recommendations. There are studied the dose, energy and angular response of the different measuring system. The range of the dose analyzed was from 0.2 mSv up to 80 mSv. The beam incidence was normal and also 20 o and 60 o . The dosimeters irradiation's were performed kerma in free in air and in phantom in order to study the availability of the service to evaluate the behavior as a function of kerma free in air or Hp(10). At the same time several items have been asked to each participant referring to the action range, the detectors characteristics, the laboratory procedures, the existence of an algorithm and its use for the dosimeter evaluation and the wish to participate in a quality assurance program. The program worked in writing a standard of personal dosimetry laboratories, that was published in 2001. In this work the results of each laboratory and its performance based on the ICRP-60 and ICRP-35 acceptance criteria are shown. Also the laboratory evolution and inquiry analyses have been included. (author)

  7. Dosimetry of clinical neutron and proton beams: An overview of recommendations

    International Nuclear Information System (INIS)

    Vynckier, S.

    2004-01-01

    Neutron therapy beams are obtained by accelerating protons or deuterons on Beryllium. These neutron therapy beams present comparable dosimetric characteristics as those for photon beams obtained with linear accelerators; for instance, the penetration of a p(65) + Be neutron beam is comparable with the penetration of an 8 MV photon beam. In order to be competitive with conventional photon beam therapy, the dosimetric characteristics of the neutron beam should therefore not deviate too much from the photon beam characteristics. This paper presents a brief summary of the neutron beams used in radiotherapy. The dosimetry of the clinical neutron beams is described. Finally, recent and future developments in the field of physics for neutron therapy is mentioned. In the last two decades, a considerable number of centres have established radiotherapy treatment facilities using proton beams with energies between 50 and 250 MeV. Clinical applications require a relatively uniform dose to be delivered to the volume to be treated, and for this purpose the proton beam has to be spread out, both laterally and in depth. The technique is called 'beam modulation' and creates a region of high dose uniformity referred to as the 'spread-out Bragg peak'. Meanwhile, reference dosimetry in these beams had to catch up with photon and electron beams for which a much longer tradition of dosimetry exists. Proton beam dosimetry can be performed using different types of dosemeters, such as calorimeters, Faraday cups, track detectors and ionisation chambers. National standard dosimetry laboratories will, however, not provide a standard for the dosimetry of proton beams. To achieve uniformity on an international level, the use of an ionisation chamber should be considered. This paper reviews and summarises the basic principles and recommendations for the absorbed dose determination in a proton beam, utilising ionisation chambers calibrated in terms of absorbed dose to water. These recommendations

  8. Internal sources dosimetry

    International Nuclear Information System (INIS)

    Savio, Eduardo

    1994-01-01

    The absorbed dose, need of estimation in risk evaluation in the application of radiopharmaceuticals in Nuclear Medicine practice,internal dosimetry,internal and external sources. Calculation methodology,Marinelli model,MIRD system for absorbed dose calculation based on biological parameters of radiopharmaceutical in human body or individual,energy of emitted radiations by administered radionuclide, fraction of emitted energy that is absorbed by target body.Limitation of the MIRD calculation model. A explanation of Marinelli method of dosimetry calculation,β dosimetry. Y dosimetry, effective dose, calculation in organs and tissues, examples. Bibliography .

  9. Dosimetry; La dosimetrie

    Energy Technology Data Exchange (ETDEWEB)

    Le Couteulx, I.; Apretna, D.; Beaugerie, M.F. [Electricite de France (EDF), 75 - Paris (France)] [and others

    2003-07-01

    Eight articles treat the dosimetry. Two articles evaluate the radiation doses in specific cases, dosimetry of patients in radiodiagnosis, three articles are devoted to detectors (neutrons and x and gamma radiations) and a computer code to build up the dosimetry of an accident due to an external exposure. (N.C.)

  10. Internal dosimetry estimates using voxelized reference phantoms for thyroid agents

    International Nuclear Information System (INIS)

    Hoseinian-Azghadi, E.; Rafat-Motavalli, L.; Miri-Hakimabad, H.

    2014-01-01

    This work presents internal dosimetry estimates for diagnostic procedures performed for thyroid disorders by relevant radiopharmaceuticals. The organ doses for 131 Iodine, 123 Iodine and 99m Tc incorporated into the body were calculated for the International Commission on Radiological Protection (ICRP) reference voxel phantoms using the Monte Carlo transport method. A comparison between different thyroid uptakes of iodine in the range of 0–55% was made, and the effect of various techniques for administration of 99m Tc on organ doses was studied. To investigate the necessity of calculating organ dose from all source regions, the major source organ and its contribution to total dose were specified for each target organ. Moreover, we compared effective dose in ICRP voxel phantoms with that in stylized phantoms. In our method, we directly calculated the organ dose without using the S values or SAFs, as is commonly done. Hence, a distribution of the absorbed dose to entire tissues was obtained. The chord length distributions (CLDs) were also computed for the selected source–target pairs to make comparison across the genders. The results showed that the S values for radionuclides in the thyroid are not sufficient for calculating the organ doses, especially for 123 I and 99m Tc. The thyroid and its neighboring organs receive a greater dose as thyroid uptake increases. Our comparisons also revealed an underestimation of organ doses reported for the stylized phantoms compared with the values based on the ICRP voxel phantoms in the uptake range of 5–55%, and an overestimation of absorbed dose by up to 2-fold for Iodine administration using blocking agent and for 99m Tc incorporation. (author)

  11. A new method for dosimetry with films radiochromic; Un nuevo metodo para la dosimetria con peliculas radiocromica

    Energy Technology Data Exchange (ETDEWEB)

    Mendez Carot, I.

    2013-07-01

    in this paper a new method is presented and the results of the comparison between the calibration is summarized based on a planning reference and calibration obtained from the irradiated fragments measure different dose levels multichannel compare dosimetry based on the weighted average dosimetry described by Micke et al.(present in the FilmQAPro software) and, finally, show different results obtained with the method proposed in several applications clinics. (Author)

  12. Aqueous chemical dosimetry

    International Nuclear Information System (INIS)

    Matthews, R.W.

    1982-01-01

    Aqueous chemical dosimetry based on ceric and ferrous sulfate solutions and on a number of fluorescence-induced systems is reviewed. Particular attention is given to the factors affecting the response of these dosimeters to radiation and the corrections necessary for more accurate dosimetry under various irradiation conditions. The effect of cerous and ceric ion, oxygen, and sulfuric acid concentration on the ceric dosimeter is discussed together with the effects of temperature, energy of radiation, degraded energy spectra, and peroxysulfuric acids. Practical aspects of ceric/cerous dosimetry are given. Although ferrous sulfate solution is the most important and widely studied reference dosimeter, general agreement has not been reached on the ''best'' value for the molar extinction coefficient of ferric ions nor on the correction necessary to the G(Fe 3 - ) value for irradiations at temperatures significantly different from 25 0 C. New data are presented which indicate that the larger temperature coefficients given in the literature are more accurate. The ferrous sulfate system has been of great importance in establishing the primary radiolytic yields for 0.4 M sulfuric acid solution; it is shown how the failure to take into account the effect of oxygen and ferrous sulfate concentrations has led to erroneously high estimates of the zero solute concentration values in acid solutions. Some of the methods for extending the dose ranges measurable with ferrous sulfate-based solutions are reviewed. Substances which on irradiation give highly fluorescent products are among the most sensitive aqueous chemical dosimeters. These include benzoate and terephthalate solutions and the more recent coumarin and trimesate solutions. Advantages and disadvantages system are discussed. (author)

  13. Status of neutron cross sections for reactor dosimetry

    International Nuclear Information System (INIS)

    Vlasov, M.F.; Fabry, A.; McElroy, W.N.

    1977-03-01

    The status of current international efforts to develop standardized sets of evaluated energy-dependent (differential) neutron cross sections for reactor dosimetry is reviewed. The status and availability of differential data are considered, some recent results of the data testing of the ENDF/B-IV dosimetry file using 252 Cf and 235 U benchmark reference neutron fields are presented, and a brief review is given of the current efforts to characterize and identify dosimetry benchmark radiation fields

  14. Research and innovation in radiation dosimetry

    International Nuclear Information System (INIS)

    Delgado, A.

    1999-01-01

    In this article some relevant lines of research in radiation dosimetry are presented. In some of them innovative approaches have been recently proposed in recent years. In others innovation is still to come as it is necessary in view of the insufficiency of the actual methods and techniques. mention is made to Thermoluminescence Dosimetry an to the improvement produced by new computational methods for the analysis of the usually complex TL signals. A solid state dosimetric technique recently proposed, Optically Stimulated Luminescence, OSL, is briefly presented. This technique promises advantages over TLD for personal and environmental dosimetry. The necessity of improving the measurement characteristics of neutron personal dosemeters is commented, making reference to some very recent developments. The situation of the dosimetry in connection with radiobiology research is overviewed, commenting the controversy on the adequacy and utility of the quality absorbed dose for these activities. Finally the special problematic of internal dosimetry is discussed. (Author) 25 refs

  15. Dosimetry Methods for Human Exposure to Non-Ionising Radiation

    International Nuclear Information System (INIS)

    Poljak, D.; Sarolic, A.; Doric, V.; Peratta, C.; Peratta, A.

    2011-01-01

    of internal current density do not exceed ICNIRP basic restrictions. Next example is related to human exposure to the magnetic field generated from RFID shop-anti theft protection system. The measured field value of 1.1 mA/m2 is significantly below ICNIRP reference levels (160 mA/m 2 for workers and 73 mA/m 2 for general population. The last example deals with the experimental incident dosimetry of GSM base station antennas. The source of GSM radiation is the roof-top antenna system in a sectorial arrangement mounted at height 48 m above ground. The radiated power per channel is P = 955 W at f = 935 MHz. The electric field measured in a flat at 15 t h floor below antenna system at approximated distance of 8 m from the radiation source is E = 0.23 V/m, which is rather negligible compared to the ICNIRP reference level E l im = 42 V/m. The obtained results from calculation and/or measurement mostly stay within the exposure limits proposed by ICNIRP safety guidelines. (author)

  16. Personal exposure to mobile phone frequencies and well-being in adults: a cross-sectional study based on dosimetry.

    Science.gov (United States)

    Thomas, Silke; Kühnlein, Anja; Heinrich, Sabine; Praml, Georg; Nowak, Dennis; von Kries, Rüdiger; Radon, Katja

    2008-09-01

    The use of mobile phone telecommunication has increased in recent years. In parallel, there is growing concern about possible adverse health effects of cellular phone networks. We used personal dosimetry to investigate the association between exposure to mobile phone frequencies and well-being in adults. A random population-based sample of 329 adults living in four different Bavarian towns was assembled for the study. Using a dosimeter (ESM-140 Maschek Electronics), we obtained an exposure profile over 24 h for three mobile phone frequency ranges (measurement interval 1 s, limit of determination 0.05 V/m). Exposure levels over waking hours were totalled and expressed as mean percentage of the International Commission on Non-Ionizing Radiation Protection (ICNIRP) reference level. Each participant reported acute symptoms in a day-long diary. Data on five groups of chronic symptoms and potential confounders were assessed during an interview. The overall exposure to high-frequency electromagnetic fields was markedly below the ICNIRP reference level. We did not find any statistically significant association between the exposure and chronic symptoms or between the exposure and acute symptoms. Larger studies using mobile phone dosimetry are warranted to confirm these findings. Copyright 2008 Wiley-Liss, Inc.

  17. Review of unfolding methods for neutron flux dosimetry

    International Nuclear Information System (INIS)

    Stallmann, F.W.; Kam, F.B.K.

    1975-01-01

    The primary method in reactor dosimetry is the foil activation technique. To translate the activation measurements into neutron fluxes, a special data processing technique called unfolding is needed. Some general observations about the problems and the reliability of this approach to reactor dosimetry are presented. Current unfolding methods are reviewed. 12 references. (auth)

  18. TH-A-204-01: Part I - Key Data for Ionizing-Radiation Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Seltzer, S. [National Institute of Standards & Technology (United States)

    2016-06-15

    The ICRU is currently finalizing a report on key data for radiation dosimetry. This multi-year review has resulted in a number of recommendations regarding “fundamental” data that are used in dosimetry related to radiation therapy. This educational session will explain the background for the ICRU committee’s work, the content and conclusions of the report and the impact on outputs, including NIST primary standards, ADCL calibration coefficients and clinical reference dosimetry. Parameters and beam modalities potentially affected by this report include: The mean excitation energy, I, for graphite, air, and water, The average energy required to create an ion pair in dry air (commonly referred to as W/e), The uncertainty in the determination of air kerma in kV x-rays The absolute value of Co-60 and Cs-137 primary standards and the dissemination of calibration coefficients, The determination of air kerma strength for Ir-192 HDR brachytherapy sources Ion chamber kQ factors for linac MV beams Ion chamber kQ factors for proton beams. The changes in reference dosimetry that would result from adoption of the ICRU recommendations are of the order of 0.5% to 1%, an effect that will not impact clinical dose delivery but will be detectable in the clinical setting. This session will also outline how worldwide metrology is coordinated through the Convention of the Meter and therefore how the international dosimetry community will proceed with adopting these recommendations so that uniformity from country to country in reference dosimetry is maintained. Timelines and communications methods will also be discussed to ensure that users, such as clinical medical physicists, are not surprised when their chamber’s calibration coefficient apparently changes. Learning Objectives: Understand the background for the ICRU committee’s work on key dosimetry data. Understand the proposed changes to key data and the impacts on reference dosimetry. Understand the methodology and timeline

  19. TH-A-204-00: Key Dosimetry Data - Impact of New ICRU Recommendations

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2016-06-15

    The ICRU is currently finalizing a report on key data for radiation dosimetry. This multi-year review has resulted in a number of recommendations regarding “fundamental” data that are used in dosimetry related to radiation therapy. This educational session will explain the background for the ICRU committee’s work, the content and conclusions of the report and the impact on outputs, including NIST primary standards, ADCL calibration coefficients and clinical reference dosimetry. Parameters and beam modalities potentially affected by this report include: The mean excitation energy, I, for graphite, air, and water, The average energy required to create an ion pair in dry air (commonly referred to as W/e), The uncertainty in the determination of air kerma in kV xrays The absolute value of Co-60 and Cs-137 primary standards and the dissemination of calibration coefficients, The determination of air kerma strength for Ir-192 HDR brachytherapy sources Ion chamber kQ factors for linac MV beams Ion chamber kQ factors for proton beams. The changes in reference dosimetry that would result from adoption of the ICRU recommendations are of the order of 0.5% to 1%, an effect that will not impact clinical dose delivery but will be detectable in the clinical setting. This session will also outline how worldwide metrology is coordinated through the Convention of the Meter and therefore how the international dosimetry community will proceed with adopting these recommendations so that uniformity from country to country in reference dosimetry is maintained. Timelines and communications methods will also be discussed to ensure that users, such as clinical medical physicists, are not surprised when their chamber’s calibration coefficient apparently changes. Learning Objectives: Understand the background for the ICRU committee’s work on key dosimetry data. Understand the proposed changes to key data and the impacts on reference dosimetry. Understand the methodology and timeline

  20. An image-based skeletal dosimetry model for the ICRP reference adult male-internal electron sources

    International Nuclear Information System (INIS)

    Hough, Matthew; Johnson, Perry; Bolch, Wesley; Rajon, Didier; Jokisch, Derek; Lee, Choonsik

    2011-01-01

    In this study, a comprehensive electron dosimetry model of the adult male skeletal tissues is presented. The model is constructed using the University of Florida adult male hybrid phantom of Lee et al (2010 Phys. Med. Biol. 55 339-63) and the EGSnrc-based Paired Image Radiation Transport code of Shah et al (2005 J. Nucl. Med. 46 344-53). Target tissues include the active bone marrow, associated with radiogenic leukemia, and total shallow marrow, associated with radiogenic bone cancer. Monoenergetic electron emissions are considered over the energy range 1 keV to 10 MeV for the following sources: bone marrow (active and inactive), trabecular bone (surfaces and volumes), and cortical bone (surfaces and volumes). Specific absorbed fractions are computed according to the MIRD schema, and are given as skeletal-averaged values in the paper with site-specific values reported in both tabular and graphical format in an electronic annex available from http://stacks.iop.org/0031-9155/56/2309/mmedia. The distribution of cortical bone and spongiosa at the macroscopic dimensions of the phantom, as well as the distribution of trabecular bone and marrow tissues at the microscopic dimensions of the phantom, is imposed through detailed analyses of whole-body ex vivo CT images (1 mm resolution) and spongiosa-specific ex vivo microCT images (30 μm resolution), respectively, taken from a 40 year male cadaver. The method utilized in this work includes: (1) explicit accounting for changes in marrow self-dose with variations in marrow cellularity, (2) explicit accounting for electron escape from spongiosa, (3) explicit consideration of spongiosa cross-fire from cortical bone, and (4) explicit consideration of the ICRP's change in the surrogate tissue region defining the location of the osteoprogenitor cells (from a 10 μm endosteal layer covering the trabecular and cortical surfaces to a 50 μm shallow marrow layer covering trabecular and medullary cavity surfaces). Skeletal

  1. An image-based skeletal dosimetry model for the ICRP reference adult male-internal electron sources

    Energy Technology Data Exchange (ETDEWEB)

    Hough, Matthew; Johnson, Perry; Bolch, Wesley [Department of Nuclear and Radiological Engineering, University of Florida, Gainesville, FL (United States); Rajon, Didier [Department of Neurosurgery, University of Florida, Gainesville, FL (United States); Jokisch, Derek [Department of Physics and Astronomy, Francis Marion University, Florence, SC (United States); Lee, Choonsik, E-mail: wbolch@ufl.edu [Radiation Epidemiology Branch, National Cancer Institute, Bethesda, MD (United States)

    2011-04-21

    In this study, a comprehensive electron dosimetry model of the adult male skeletal tissues is presented. The model is constructed using the University of Florida adult male hybrid phantom of Lee et al (2010 Phys. Med. Biol. 55 339-63) and the EGSnrc-based Paired Image Radiation Transport code of Shah et al (2005 J. Nucl. Med. 46 344-53). Target tissues include the active bone marrow, associated with radiogenic leukemia, and total shallow marrow, associated with radiogenic bone cancer. Monoenergetic electron emissions are considered over the energy range 1 keV to 10 MeV for the following sources: bone marrow (active and inactive), trabecular bone (surfaces and volumes), and cortical bone (surfaces and volumes). Specific absorbed fractions are computed according to the MIRD schema, and are given as skeletal-averaged values in the paper with site-specific values reported in both tabular and graphical format in an electronic annex available from http://stacks.iop.org/0031-9155/56/2309/mmedia. The distribution of cortical bone and spongiosa at the macroscopic dimensions of the phantom, as well as the distribution of trabecular bone and marrow tissues at the microscopic dimensions of the phantom, is imposed through detailed analyses of whole-body ex vivo CT images (1 mm resolution) and spongiosa-specific ex vivo microCT images (30 {mu}m resolution), respectively, taken from a 40 year male cadaver. The method utilized in this work includes: (1) explicit accounting for changes in marrow self-dose with variations in marrow cellularity, (2) explicit accounting for electron escape from spongiosa, (3) explicit consideration of spongiosa cross-fire from cortical bone, and (4) explicit consideration of the ICRP's change in the surrogate tissue region defining the location of the osteoprogenitor cells (from a 10 {mu}m endosteal layer covering the trabecular and cortical surfaces to a 50 {mu}m shallow marrow layer covering trabecular and medullary cavity surfaces). Skeletal

  2. Dosimetry and shielding

    International Nuclear Information System (INIS)

    Farinelli, U.

    1977-01-01

    Today, reactor dosimetry and shielding have wide areas of overlap as concerns both problems and methods. Increased interchange of results and know-how would benefit both. The areas of common interest include calculational methods, sensitivity studies, theoretical and experimental benchmarks, cross sections and other nuclear data, multigroup libraries and procedures for their adjustment, experimental techniques and damage functions. This paper reviews the state-of-the-art and the latest development in each of these areas as far as shielding is concerned, and suggests a number of interactions that could be profitable for reactor dosimetry. Among them, re-evaluation of the potentialities of calculational methods (in view of the recent developments) in predicting radiation environments of interest; the application of sensitivity analysis to dosimetry problems; a common effort in the field of theoretical benchmarks; the use of the shielding one-material propagation experiments as reference spectra for detector cross sections; common standardization of the detector nuclear data used in both fields; the setting up of a common (or compatible) multigroup structure and library applicable to shielding, dosimetry and core physics; the exchange of information and experience in the fields of cross section errors, correlations and adjustment; and the intercomparison of experimental techniques

  3. Investigation of the Spatial Resolution of MR-Based Polymer Gel Dosimetry versus Film Densitometry using Dose Modulation Transfer Function

    Directory of Open Access Journals (Sweden)

    Reza Moghadam-Drodkhani

    2011-03-01

    Full Text Available Introduction: The conventional methods of dosimetry are not capable of dosimetry in such a small volume of less than one cubic millimeter. Although the polymer gel dosimetry method based on magnetic resonance imaging (MRI could achieve three dimensional dosimetry with high resolution, a spatial resolution evaluation based on gel dose modulation transfer function has not been investigated yet. Therefore, in this study, the spatial resolution of two systems of film densitometry and polymer gel dosimetry based on MRI has been evaluated by using the dose modulation transfer function (DMTF.   Material and Methods: Kodak therapy verification films and MAGICA polymer gel samples were positioned below a brass absorption grid with different periodic slices (a/2= 280, 525, 1125 μm, which was placed in a water bath container to avoid regions of dose build-up just below the absorption grid and then irradiated with Cobalt-60 photons on a Theratron external-beam treatment unit. Dose variation under the brass grid was determined using a calibration curve, while transverse relaxation time (T2 as the selective parameter in a dose image based on multiple echo MRI with 1.5 Tesla GE Signa Echo Speed system (FOV=10 cm, matrix size=512 ×512, pixel size =0.199×0.199 mm2, TE = 20, 40, 60, 80 ms, TR=4200 ms, NEX = 4, slice thickness=2 mm, gap=1 mm was calculated. DMTF from the modulation depths of T2 and variation in film optical density after calibration would be achieved. The results of polymer gel were compared with film. Results: After deriving the dose distribution profile under the absorption grid, minima and maxima at the smallest period of a = 560 μm could scarcely be resolved, but the modulations due to a=2250 μm and a = 1050 μm grids could be discerned. The modulation depth for a=2250 μm grid was set to 100% and the other modulations were subsequently referred to this maximum modulation. For film densitometry at a = 1050 μm, the modulation depth was

  4. SU-E-T-284: Revisiting Reference Dosimetry for the Model S700 Axxent 50 KVp Electronic Brachytherapy Source

    International Nuclear Information System (INIS)

    Hiatt, JR; Rivard, MJ

    2014-01-01

    Purpose: The model S700 Axxent electronic brachytherapy source by Xoft was characterized in 2006 by Rivard et al. The source design was modified in 2006 to include a plastic centering insert at the source tip to more accurately position the anode. The objectives of the current study were to establish an accurate Monte Carlo source model for simulation purposes, to dosimetrically characterize the new source and obtain its TG-43 brachytherapy dosimetry parameters, and to determine dose differences between the source with and without the centering insert. Methods: Design information from dissected sources and vendor-supplied CAD drawings were used to devise the source model for radiation transport simulations of dose distributions in a water phantom. Collision kerma was estimated as a function of radial distance, r, and polar angle, θ, for determination of reference TG-43 dosimetry parameters. Simulations were run for 10 10 histories, resulting in statistical uncertainties on the transverse plane of 0.03% at r=1 cm and 0.08% at r=10 cm. Results: The dose rate distribution the transverse plane did not change beyond 2% between the 2006 model and the current study. While differences exceeding 15% were observed near the source distal tip, these diminished to within 2% for r>1.5 cm. Differences exceeding a factor of two were observed near θ=150° and in contact with the source, but diminished to within 20% at r=10 cm. Conclusions: Changes in source design influenced the overall dose rate and distribution by more than 2% over a third of the available solid angle external from the source. For clinical applications using balloons or applicators with tissue located within 5 cm from the source, dose differences exceeding 2% were observed only for θ>110°. This study carefully examined the current source geometry and presents a modern reference TG-43 dosimetry dataset for the model S700 source

  5. Neutron dosimetry and spectrometry with Bonner spheres. Working out a log-normal reference matrix

    International Nuclear Information System (INIS)

    Zaborowski, Henrick.

    1981-11-01

    From the experimental and theoretical studies made upon the BONNER's spheres System with a I 6 Li(Eu) crystal and with a miniaturized 3 He counter we get the normalized energy response functions R*sub(i)(E). This normalization is obtained by the mathematization of the Resolution Function R*(i,E) in the Log-Normal distribution hypothesis to mono energetic neutrons given in April 1976 to the International Symposium on Californium 252. The fit of the Log-Normal Hypothesis with the experimental and Theoretical data is very satisfactory. The parameter's tabulated values allow a precise interpolation, at all energies between 0.4 eV and 15 MeV and for all spheres diameters between 2 and 12 inches, of the discretized R*sub(ij) Reference Matrix for the applications to neutron dosimetry and spectrometry [fr

  6. Dosimetry systems for radiation processing in Japan

    International Nuclear Information System (INIS)

    Tamura, Naoyuki

    1995-01-01

    The present situation of dosimetry systems for radiation processing industry in Japan is reviewed. For gamma-rays irradiation the parallel-plate ionization chamber in TRCRE, JAERI has been placed as a reference standard dosimeter for processing-level dose. Various solid and liquid chemical dosimeters are used as routine dosimeters for gamma processing industries. Alanine dosimeters is used for the irradiation purpose which needs precise dosimetry. For electron-beam irradiation the electron current density meter and the total absorption calorimeter of TRCRE are used for the calibration of routine dosimeters. Plastic film dosimeters, such as cellulose triacetate and radiochromic dye are used as routine dosimeters for electron processing industries. When the official traceability systems for processing-level dosimetry now under investigation is completed, the ionization chamber of TRCRE is expected to have a role of the primary standard dosimeter and the specified alanine dosimeter will be nominated for the secondary or reference standard dosimeter. (author)

  7. Performance of dichromate dosimetry systems in calibration and dose intercomparison

    International Nuclear Information System (INIS)

    Bof, E.S.; Smolko, E.

    1999-01-01

    This report presents the results of the High Dose Dosimetry Laboratory of Argentina during ten years of international intercomparisons for high dose with the International Dose Assurance Service (IDAS) of the IAEA, using the standard high dose dichromate dosimetry system, and the results of a high dose intercomparison regional exercise in which our Laboratory acted as a reference laboratory, using the standard high dose and low dose dichromate dosimetry system. (author)

  8. Development a high-resolution radiation dosimetry system based on Fricke solutions

    Energy Technology Data Exchange (ETDEWEB)

    Vedelago, J. [Laboratorio de Investigaciones e Instrumentacion en Fisica Aplicada a la Medicina e Imagenes por Rayos X, Laboratorio 448 FaMAF - UNC, Ciudad Universitaria, 5000 Cordoba (Argentina); Mattea, F. [Universidad Nacional de Cordoba, Facultad de Ciencias Quimicas, Departamento de Quimica Organica, Ciudad Universitaria, 5000 Cordoba (Argentina); Valente, M., E-mail: josevedelago@gmail.com [Instituto de Fisica E. Gaviola, Oficina 102 FaMAF - UNC, Ciudad Universitaria, 5000 Cordoba (Argentina)

    2014-08-15

    Due to the growing complexity of modern medical procedures involving the use of ionizing radiation, dosimetry by non-conventional techniques is one of the research areas in the field of greatest interest nowadays. Tissue-equivalent high-resolution dosimetry systems capable of attaining continuous dose mapping are required. In this scenario, Fricke gel dosimetry is a very promising option for in-phantom dose measurements in complex radiation techniques. Implementation of this technique requires dedicated instruments capable of measuring and performing the immediate in situ analysis of the acquired data at the radiation facility. The versatility of Fricke gel dosimetry in different applications depending on the chemical and isotopic composition of the dosimeter extends its application to different high performance conventional and non-conventional radiation procedures involving diverse types of radiation treatments and also radiation diagnosis procedures. This work presents an integral dosimetry system, based on Fricke gel solutions and their analysis by optical techniques, aiming for an increase in the precision on dose determinations. The chemical synthesis and dosimeter preparation were accomplished at LIIFAMIRx facilities, following the procedures and protocols described in previous works. Additionally, specific instrumentation for optical sample analysis was completely designed and constructed at LIIFAMIRx facilities. The main outcome of this work was the development of a methodology that improves the integral dose determination performance by the pre-irradiation of Fricke gel dosimeters. (author)

  9. Development a high-resolution radiation dosimetry system based on Fricke solutions

    International Nuclear Information System (INIS)

    Vedelago, J.; Mattea, F.; Valente, M.

    2014-08-01

    Due to the growing complexity of modern medical procedures involving the use of ionizing radiation, dosimetry by non-conventional techniques is one of the research areas in the field of greatest interest nowadays. Tissue-equivalent high-resolution dosimetry systems capable of attaining continuous dose mapping are required. In this scenario, Fricke gel dosimetry is a very promising option for in-phantom dose measurements in complex radiation techniques. Implementation of this technique requires dedicated instruments capable of measuring and performing the immediate in situ analysis of the acquired data at the radiation facility. The versatility of Fricke gel dosimetry in different applications depending on the chemical and isotopic composition of the dosimeter extends its application to different high performance conventional and non-conventional radiation procedures involving diverse types of radiation treatments and also radiation diagnosis procedures. This work presents an integral dosimetry system, based on Fricke gel solutions and their analysis by optical techniques, aiming for an increase in the precision on dose determinations. The chemical synthesis and dosimeter preparation were accomplished at LIIFAMIRx facilities, following the procedures and protocols described in previous works. Additionally, specific instrumentation for optical sample analysis was completely designed and constructed at LIIFAMIRx facilities. The main outcome of this work was the development of a methodology that improves the integral dose determination performance by the pre-irradiation of Fricke gel dosimeters. (author)

  10. Topics in radiation dosimetry radiation dosimetry

    CERN Document Server

    1972-01-01

    Radiation Dosimetry, Supplement 1: Topics in Radiation Dosimetry covers instruments and techniques in dealing with special dosimetry problems. The book discusses thermoluminescence dosimetry in archeological dating; dosimetric applications of track etching; vacuum chambers of radiation measurement. The text also describes wall-less detectors in microdosimetry; dosimetry of low-energy X-rays; and the theory and general applicability of the gamma-ray theory of track effects to various systems. Dose equivalent determinations in neutron fields by means of moderator techniques; as well as developm

  11. Twenty-first nuclear accident dosimetry intercomparison study, August 6-10, 1984

    International Nuclear Information System (INIS)

    Swaja, R.E.; Ragan, G.E.; Sims, C.S.

    1985-05-01

    The twenty-first in a series of nuclear accident dosimetry (NAD) intercomparison (NAD) studies was conducted at the Oak Ridge National Laboratory's Dosimetry Applications Research Facility during August 6-10, 1984. The Health Physics Research Reactor operated in the pulse mode was used to simulate three criticality accidents with different radiation fields. Participants from five organizations measured neutron doses between 0.53 and 4.36 Gy and gamma doses between 0.19 and 1.01 Gy at area monitoring stations and on phantoms. About 75% of all neutron dose estimates based on foil activation, hair activation, simulated blood sodium activation, and thermoluminescent methods were within +-25% of reference values. Approximately 86% of all gamma results measured using thermoluminescent (TLD-700 or CaSO 4 ) systems were within +-20% of reference doses which represents a significant improvement over previous studies. Improvements observed in the ability of intercomparison participants to estimate neutron and gamma doses under criticality accident conditions can be partly attributed to experience in previous NAD studies which have provided practical tests of dosimetry systems, enabled participants to improve evaluation methods, and standardized dose reporting conventions. 16 refs., 15 tabs

  12. Harmonization of internal dosimetry procedures in Latin America - ARCAL/IAEA project

    Energy Technology Data Exchange (ETDEWEB)

    Melo, D.; Dantas, B.M.; Juliao, L. [Instituto de Radioprotecao e Dosimetria - Av. Salvador Allende S/N, Recreio dos Bandeirantes, RJ 22780-160 (Brazil); Cruz Suarez, R. [International Atomic Energy Agency, Vienna (Austria); Rojo, A.; Serdero, N. [Autoridad Regulatoria Nuclear, Buenos Aires (Argentina); Videla, R. [Comision Chilena de Energia Nuclear, Santiago (Chile); Puerta, J.A. [Universidad Nacional de Colombia, Medellin (Colombia); Lopez, G. [Centro de Proteccion e Higiene de las Radiaciones, Ciudad de la Habana (Cuba); Alfaro, M.M. [Instituto nacional de Investigaciones Nucleares (Mexico); Gonzales, S. [Instituto Peruano de Energia Nuclear, Lima (Peru); Hermida, J.C. [Hospital de Clinicas, Montevideo (Uruguay); Navarro, T. [Centro de Investigaciones Energeticas, Mediciones Ambientales y Tecnologicas - CIEMAT, Madrid (Spain)

    2007-07-01

    Under the auspices of the Regional Coordination Agreement for Latin America, representatives of the eight member states have participated in a project to improve radiological protection for workers exposed to unsealed sources of radiation. The design of the project was based on information obtained from a questionnaire circulated among the participants, from which the initial status of internal dosimetry services in each country was characterised. The objective of the project is to harmonize internal dosimetry procedures, with reference to International Atomic Energy Agency recommendations. After the implementation of new procedures and personnel training, four intercomparison exercises were carried out: measurement of iodine in thyroid phantoms, measurement of gamma emitters in urine samples, measurement of beta emitters in urine samples and internal dose assessments. This project has resulted in important improvements in internal dosimetry services in the region. (authors)

  13. Manual of food irradiation dosimetry

    International Nuclear Information System (INIS)

    1977-01-01

    Following items are discussed: Fundamentals of dosimetry; description of irradiators; dose distribution in the product and commissioning the process; plant operation and process control; detailed instructions on using various dose-meter systems; references; glossary of some basic terms and concepts

  14. Dosimetry of ionizing radiation

    International Nuclear Information System (INIS)

    Musilek, L.; Seda, J.; Trousil, J.

    1992-01-01

    The publication deals with a major field of ionizing radiation dosimetry, viz., integrating dosimetric methods, which are the basic means of operative dose determination. It is divided into the following sections: physical and chemical effects of ionizing radiation; integrating dosimetric methods for low radiation doses (film dosimetry, nuclear emulsions, thermoluminescence, radiophotoluminescence, solid-state track detectors, integrating ionization dosemeters); dosimetry of high ionizing radiation doses (chemical dosimetric methods, dosemeters based on the coloring effect, activation detectors); additional methods applicable to integrating dosimetry (exoelectron emission, electron spin resonance, lyoluminescence, etc.); and calibration techniques for dosimetric instrumentation. (Z.S.). 422 refs

  15. Standardization of the calibration of brachytherapy sources at the IAEA dosimetry laboratory

    International Nuclear Information System (INIS)

    Shanta, A.; Andreo, P.

    1996-01-01

    A new service to SSDLs has been initiated at the IAEA Dosimetry Laboratory for providing calibrations of well-type ionisation chambers, used in brachytherapy applications, which are traceable to the International Measurement System. Considering that the most common radionuclide used in the developing countries is 137 Cs, two such sources of the type used for gynaecological intracavitary applications have been purchased by the Agency and calibrated at the National Institute of Standards and Technology (NIST), USA. These 137 Cs reference sources together with a well-type ionization chamber constitute the IAEA brachytherapy dosimetry standard. Based on the recommendations by a group of experts, a method has been developed for transferring calibrations to SSDLs which is described in this paper. The method is based on the acquisition by the SSDLs of sources and equipment similar to those at the IAEA. The well-type chamber is to be calibrated at the IAEA Dosimetry Laboratory, and this will be used at the SSDL to calibrate its own reference sources. These sources can in turn by used to calibrate well-type chambers from hospital users and to calibrate other type of sources by performing measurements in air. In order to standardize the procedures for the two methods and to provide guidance to the SSDLs, measurements have been carried out at the IAEA Dosimetry Laboratory. The reproducibility of the two type of measurements has been found to be better than 0.5%, and the uncertainty of calibrations estimated to be less than 1.5% (one standard deviation). (author). 8 refs, 8 figs, 2 tabs

  16. A CaS : Ce, Sm-based dosimeter for online dosimetry measurement

    International Nuclear Information System (INIS)

    Sun Yurun; Chen Zhaoyang; Fan Yanwei; Yan Shiyou; He Chengfa

    2011-01-01

    A film dosimeter based on optically stimulated luminescence (OSL) material of CaS : Ce, Sm was developed for online irradiation dosimetry measurement. The stimulation is provided by a laser with a wavelength of 980 nm, and the OSL luminescence is collected by a photodiode. Using 60 Co γ-rays, we investigated the dosimetry characteristic of the dosimeter at different dose rates and total doses. The real-time detection results showed that the OSL signals versus total ionizing dose exhibited a good linearity in a dose range of 0.1-185 Gy. (authors)

  17. Textbook of dosimetry. 4. ed.

    International Nuclear Information System (INIS)

    Ivanov, V.I.

    1999-01-01

    This textbook of dosimetry is devoted to the students in physics and technical physics of high education institutions, confronted with different application of atomic energy as well as with protection of population and environment against ionizing radiations. Atomic energy is highly beneficial for man but unfortunately incorporates potential dangers which manifest in accidents, the source of which is either insufficient training of the personnel, a criminal negligence or insufficient reliability of the nuclear facilities. The majority of the incident and accident events have had as origin the personnel errors. This was the case with both the 'Three Miles Island' (1979) and Chernobyl (1986) NPP accidents. The dosimetry science acquires a vital significance in accident situations since the data obtained by its procedures are essential in choosing the correct immediate actions, behaviour tactics, orientation of liquidation of accident consequences as well as in ensuring the health of population. An important accent is placed in this manual on clarification of the nature of physical processes taken place in dosimetric detectors, in establishing the relation between radiation field characteristics and the detector response as well as in defining different dosimetric quantities. The terminology and the units of physical quantities is based on the international system of units. The book contains the following 15 chapters: 1. Ionizing radiation field; 2. Radiation doses; 3. Physical bases of gamma radiation dosimetry; 4. Ionization dosimetric detectors; 5. Semiconductor dosimetric detectors; 6. Scintillation detection in the gamma radiation dosimetry; 7. Luminescent methods in dosimetry; 8. The photographic and chemical methods of gamma radiation dosimetry; 9. Neutron dosimetry; 10. Dosimetry of high intensity radiation; 11. Dosimetry of high energy Bremsstrahlung; 12. Measurement of the linear energy transfer; 13. Microdosimetry; 14. Dosimetry of incorporated

  18. User's guide for survey-meter- and film-badge-dosimetry data bases

    International Nuclear Information System (INIS)

    Phillips, W.G.; Sherman, S.; Young, R.

    1981-05-01

    This manual describes the data storage and retrieval system designed by Environmental Monitoring Systems Laboratory Las Vegas (EMSL-LV) for radiation exposure data recorded in offsite areas during and after nuclear weapons tests conducted at the Nevada Test Site in the 1950's and early 1960's. Referred to hereinafter as the EMSL-LV system, this system contains two distinct subsets of offsite radiological measurements collected during early nuclear atmospheric tests at the Nevada Test Site. The purpose of the manual is to present the methods for using the EMSL-LV system to examine all or any portion of either data subset. The two distinct subsets which comprise the EMSL-LV system are survey meter data and film badge dosimetry data. The survey meter data consist of readings obtained from portable radiation monitoring instruments used around the Nevada Test Site during the 1950's and early 1960's to measure radiation exposure rates resulting from the nuclear testing program. The dosimetry data consist of measurements of integrated radiation exposure made with film badge type dosimeters in areas surrounding the Nevada Test Site

  19. European protocol for neutron dosimetry for external beam therapy

    International Nuclear Information System (INIS)

    Broerse, J.J.; Mijnheer, B.J.; Williams, J.R.

    1981-01-01

    The paper attempts to serve the needs of European centres participating in the High LET Therapy Project Group set up under the sponsorship of The European Organization for Research on Treatment of Cancer, to promote cooperation between physicists involved in fast neutron therapy and establish a common basis for neutron dosimetry. Differences in dosimetry procedures between European and American Groups are indicated if relevant. The subject is dealt with under the following main headings: principles of dosimetry of neutron fields, dosimetric methods, physical parameters, determination of absorbed dose at a reference point, determination of absorbed dose at any point, check of absorbed dose given to a patient, dosimetry intercomparisons between institutes. There is an ample bibliography. (U.K.)

  20. Review of present beta dosimetry problems in radiation protection; to day's answers and future trends

    International Nuclear Information System (INIS)

    Fracas, P.

    1986-01-01

    The large use of pure beta radionuclides needs to be develop beta dosimetry methods for radiation protection. The different types of present dosimetry assessments are reviewed. In all the cases the quantity to take into account is the absorbed dose rate in human tissus and more particularly in skin. In the case of point sources of known nature and activity this quantity can be worked out. This calculation is achieved either by incident beta spectrum analysis or theoretical considerations based on Kernel point. The absorbed dose rate can also be measured by extrapolation ionization chamber which characteristics and working are detailed here. All present survey meter were not initially planned for such a beta dosimetry, as this performed with the extrapolation ionization chamber which is taken here as a reference. So responses of usual dosimeters compared to this reference need to be estimated. Responses of personal film badges used in CEA, portable ionization chambers as babyline, pocket dosimeters SEQ7 and the thermoluminescent dosimeters TLD700 are exposed here. Results show that all these survey meters are not completely suitable for routine beta dosimetry. Consequently other operational dosimetry techniques have to be pursued. In particular some thermoluminescence dosimeters for instance boron diffused in surface layer and multi-elements, and furthermore Thermally Stimulated Exoelectron Emission (TSEE) and surface barrier detectors are described [fr

  1. Pulse-resolved radiotherapy dosimetry using fiber-coupled organic scintillators

    Energy Technology Data Exchange (ETDEWEB)

    Ravnsborg Beierholm, A.

    2011-05-15

    This PhD project pertains to the development and adaptation of a dosimetry system that can be used to verify the delivery of radiation in modern radiotherapy modalities involving small radiation fields and dynamic radiation delivery. The dosimetry system is based on fibre-coupled organic scintillators and can be perceived as a well characterized, independent alternative to the methods that are in clinical use today. The dosimeter itself does not require a voltage supply, and is composed of water equivalent materials. The dosimeter can be fabricated with a sensitive volume smaller than a cubic millimeter, which is small enough to resolve the small radiation fields encountered in modern radiotherapy. The fast readout of the dosimeter enables measurements on the same time scale as the pulsed radiation delivery from the medical linear accelerators used for treatment. The dosimetry system, comprising fiber-coupled organic scintillators and data acquisition hardware, was developed at the Radiation Research Division at Risoe DTU and tested using clinical x-ray beams at hospitals in Denmark and abroad. Measurements of output factors and percentage depth dose were performed and compared with reference values and Monte Carlo simulations for static square radiation fields for standard (4 cm x 4 cm to 20 cm x 20 cm) and small (down to 0.6 cm x 0.6 cm) field sizes. The accuracy of most of the obtained measurements was good, agreeing with reference and simulated dose values to within 2 % standard deviation for both standard and small fields. This thesis concludes that the new pulse-resolved dosimetry system holds great potential for modern radiotherapy applications, such as stereotactic radiotherapy and intensity-modulated radiotherapy. (Author)

  2. Pulse-resolved radiotherapy dosimetry using fiber-coupled organic scintillators

    International Nuclear Information System (INIS)

    Ravnsborg Beierholm, A.

    2011-05-01

    This PhD project pertains to the development and adaptation of a dosimetry system that can be used to verify the delivery of radiation in modern radiotherapy modalities involving small radiation fields and dynamic radiation delivery. The dosimetry system is based on fibre-coupled organic scintillators and can be perceived as a well characterized, independent alternative to the methods that are in clinical use today. The dosimeter itself does not require a voltage supply, and is composed of water equivalent materials. The dosimeter can be fabricated with a sensitive volume smaller than a cubic millimeter, which is small enough to resolve the small radiation fields encountered in modern radiotherapy. The fast readout of the dosimeter enables measurements on the same time scale as the pulsed radiation delivery from the medical linear accelerators used for treatment. The dosimetry system, comprising fiber-coupled organic scintillators and data acquisition hardware, was developed at the Radiation Research Division at Risoe DTU and tested using clinical x-ray beams at hospitals in Denmark and abroad. Measurements of output factors and percentage depth dose were performed and compared with reference values and Monte Carlo simulations for static square radiation fields for standard (4 cm x 4 cm to 20 cm x 20 cm) and small (down to 0.6 cm x 0.6 cm) field sizes. The accuracy of most of the obtained measurements was good, agreeing with reference and simulated dose values to within 2 % standard deviation for both standard and small fields. This thesis concludes that the new pulse-resolved dosimetry system holds great potential for modern radiotherapy applications, such as stereotactic radiotherapy and intensity-modulated radiotherapy. (Author)

  3. Clinical dosimetry

    International Nuclear Information System (INIS)

    Rassow, J.

    1973-01-01

    The main point of this paper on clinical dosimetry which is to be understood here as application of physical dosimetry on accelerators in medical practice, is based on dosimetric methodics. Following an explanation of the dose parameters and description of the dose distribution important for clinical practice as well as geometric irradiation parameters, the significance of a series of physical parameters such as accelerator energy, surface energy of average stopping power etc. is dealt with in detail. Following a section on field homogenization with bremsstrahlung and electron radiation, details on dosimetry in clinical practice are given. Finally, a few problems of dosemeter or monitor calibration on accelerators are described. The explanations are supplemented by a series of diagrams and tables. (ORU/LH) [de

  4. Modelling of a holographic interferometry based calorimeter for radiation dosimetry

    Science.gov (United States)

    Beigzadeh, A. M.; Vaziri, M. R. Rashidian; Ziaie, F.

    2017-08-01

    In this research work, a model for predicting the behaviour of holographic interferometry based calorimeters for radiation dosimetry is introduced. Using this technique for radiation dosimetry via measuring the variations of refractive index due to energy deposition of radiation has several considerable advantages such as extreme sensitivity and ability of working without normally used temperature sensors that disturb the radiation field. We have shown that the results of our model are in good agreement with the experiments performed by other researchers under the same conditions. This model also reveals that these types of calorimeters have the additional and considerable merits of transforming the dose distribution to a set of discernible interference fringes.

  5. Individual dosimetry and calibration

    International Nuclear Information System (INIS)

    Otto, T.

    1997-01-01

    In 1996, the Dosimetry and Calibration Section was, as in previous years, mainly engaged in routine tasks: the distribution of over 6000 dosimeters (with a total of more than 10,000 films) every two months and the calibration of about 900 fixed and mobile instruments used in the radiation survey sections of RP group. These tasks were, thanks to an experienced team, well mastered. Special efforts had to be made in a number of areas to modernize the service or to keep it in line with new prescriptions. The Individual Dosimetry Service had to assure that CERN's contracting firms comply with the prescriptions in the Radiation Safety Manual (1996) that had been inspired by the Swiss Ordinance of 1994: Companies must file for authorizations with the Swiss Federal Office for Public Health requiring that in every company an 'Expert in Radiation Protection' be nominated and subsequently trained. CERN's Individual Dosimetry Service is accredited by the Swiss Federal Authorities and works closely together with other, similar services on a rigorous quality assurance programme. Within this framework, CERN was mandated to organize this year the annual Swiss 'Intercomparison of Dosimeters'. All ten accredited dosimetry services - among others those of the Paul Scherrer Institute (PSI) in Villigen and of the four Swiss nuclear power stations - sent dosimeters to CERN, where they were irradiated in CERN's calibration facility with precise photon doses. After return to their origin they were processed and evaluated. The results were communicated to CERN and were compared with the originally given doses. A report on the results was subsequently prepared and submitted to the Swiss 'Group of Experts on Personal Dosimetry'. Reference monitors for photon and neutron radiation were brought to standard laboratories to assure the traceability of CERN's calibration service to the fundamental quantities. For photon radiation, a set of ionization chambers was calibrated in the reference field

  6. JENDL Dosimetry File

    International Nuclear Information System (INIS)

    Nakazawa, Masaharu; Iguchi, Tetsuo; Kobayashi, Katsuhei; Iwasaki, Shin; Sakurai, Kiyoshi; Ikeda, Yujiro; Nakagawa, Tsuneo.

    1992-03-01

    The JENDL Dosimetry File based on JENDL-3 was compiled and integral tests of cross section data were performed by the Dosimetry Integral Test Working Group of the Japanese Nuclear Data Committee. Data stored in the JENDL Dosimetry File are the cross sections and their covariance data for 61 reactions. The cross sections were mainly taken from JENDL-3 and the covariances from IRDF-85. For some reactions, data were adopted from other evaluated data files. The data are given in the neutron energy region below 20 MeV in both of point-wise and group-wise files in the ENDF-5 format. In order to confirm reliability of the data, several integral tests were carried out; comparison with the data in IRDF-85 and average cross sections measured in fission neutron fields, fast reactor spectra, DT neutron fields and Li(d, n) neutron fields. As a result, it has been found that the JENDL Dosimetry File gives better results than IRDF-85 but there are some problems to be improved in future. The contents of the JENDL Dosimetry File and the results of the integral tests are described in this report. All of the dosimetry cross sections are shown in a graphical form. (author) 76 refs

  7. JENDL Dosimetry File

    Energy Technology Data Exchange (ETDEWEB)

    Nakazawa, Masaharu; Iguchi, Tetsuo [Tokyo Univ. (Japan). Faculty of Engineering; Kobayashi, Katsuhei [Kyoto Univ., Kumatori, Osaka (Japan). Research Reactor Inst.; Iwasaki, Shin [Tohoku Univ., Sendai (Japan). Faculty of Engineering; Sakurai, Kiyoshi; Ikeda, Yujior; Nakagawa, Tsuneo [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1992-03-15

    The JENDL Dosimetry File based on JENDL-3 was compiled and integral tests of cross section data were performed by the Dosimetry Integral Test Working Group of the Japanese Nuclear Data Committee. Data stored in the JENDL Dosimetry File are the cross sections and their covariance data for 61 reactions. The cross sections were mainly taken from JENDL-3 and the covariances from IRDF-85. For some reactions, data were adopted from other evaluated data files. The data are given in the neutron energy region below 20 MeV in both of point-wise and group-wise files in the ENDF-5 format. In order to confirm reliability of the data, several integral tests were carried out; comparison with the data in IRDF-85 and average cross sections measured in fission neutron fields, fast reactor spectra, DT neutron fields and Li(d,n) neutron fields. As a result, it has been found that the JENDL Dosimetry File gives better results than IRDF-85 but there are some problems to be improved in future. The contents of the JENDL Dosimetry File and the results of the integral tests are described in this report. All of the dosimetry cross sections are shown in a graphical form.

  8. Dosimetry for audit and clinical trials: challenges and requirements

    International Nuclear Information System (INIS)

    Kron, T; Haworth, A; Williams, I

    2013-01-01

    Many important dosimetry audit networks for radiotherapy have their roots in clinical trial quality assurance (QA). In both scenarios it is essential to test two issues: does the treatment plan conform with the clinical requirements and is the plan a reasonable representation of what is actually delivered to a patient throughout their course of treatment. Part of a sound quality program would be an external audit of these issues with verification of the equivalence of plan and treatment typically referred to as a dosimetry audit. The increasing complexity of radiotherapy planning and delivery makes audits challenging. While verification of absolute dose delivered at a reference point was the standard of external dosimetry audits two decades ago this is often deemed inadequate for verification of treatment approaches such as Intensity Modulated Radiation Therapy (IMRT) and Volumetric Modulated Arc Therapy (VMAT). As such, most dosimetry audit networks have successfully introduced more complex tests of dose delivery using anthropomorphic phantoms that can be imaged, planned and treated as a patient would. The new challenge is to adapt this approach to ever more diversified radiotherapy procedures with image guided/adaptive radiotherapy, motion management and brachytherapy being the focus of current research.

  9. SU-E-T-284: Revisiting Reference Dosimetry for the Model S700 Axxent 50 KV{sub p} Electronic Brachytherapy Source

    Energy Technology Data Exchange (ETDEWEB)

    Hiatt, JR [Rhode Island Hospital, Providence, RI (United States); Rivard, MJ [Tufts University School of Medicine, Boston, MA (United States)

    2014-06-01

    Purpose: The model S700 Axxent electronic brachytherapy source by Xoft was characterized in 2006 by Rivard et al. The source design was modified in 2006 to include a plastic centering insert at the source tip to more accurately position the anode. The objectives of the current study were to establish an accurate Monte Carlo source model for simulation purposes, to dosimetrically characterize the new source and obtain its TG-43 brachytherapy dosimetry parameters, and to determine dose differences between the source with and without the centering insert. Methods: Design information from dissected sources and vendor-supplied CAD drawings were used to devise the source model for radiation transport simulations of dose distributions in a water phantom. Collision kerma was estimated as a function of radial distance, r, and polar angle, θ, for determination of reference TG-43 dosimetry parameters. Simulations were run for 10{sup 10} histories, resulting in statistical uncertainties on the transverse plane of 0.03% at r=1 cm and 0.08% at r=10 cm. Results: The dose rate distribution the transverse plane did not change beyond 2% between the 2006 model and the current study. While differences exceeding 15% were observed near the source distal tip, these diminished to within 2% for r>1.5 cm. Differences exceeding a factor of two were observed near θ=150° and in contact with the source, but diminished to within 20% at r=10 cm. Conclusions: Changes in source design influenced the overall dose rate and distribution by more than 2% over a third of the available solid angle external from the source. For clinical applications using balloons or applicators with tissue located within 5 cm from the source, dose differences exceeding 2% were observed only for θ>110°. This study carefully examined the current source geometry and presents a modern reference TG-43 dosimetry dataset for the model S700 source.

  10. Selective saturation method for EPR dosimetry with tooth enamel

    International Nuclear Information System (INIS)

    Ignatiev, E.A.; Romanyukha, A.A.; Koshta, A.A.; Wieser, A.

    1996-01-01

    The method of selective saturation is based on the difference in the microwave (mw) power dependence of the background and radiation induced EPR components of the tooth enamel spectrum. The subtraction of the EPR spectrum recorded at low mw power from that recorded at higher mw power provides a considerable reduction of the background component in the spectrum. The resolution of the EPR spectrum could be improved 10-fold, however simultaneously the signal-to-noise ratio was found to be reduced twice. A detailed comparative study of reference samples with known absorbed doses was performed to demonstrate the advantage of the method. The application of the selective saturation method for EPR dosimetry with tooth enamel reduced the lower limit of EPR dosimetry to about 100 mGy. (author)

  11. Introduction [International Reactor Dosimetry File 2002 (IRDF-2002)

    International Nuclear Information System (INIS)

    Paviotti-Corcuera, R.; Zolnay, E.M.

    2006-01-01

    service life of reactor pressure vessels. Accurate cross-section data are also essential in other neutron metrology applications such as boron neutron capture therapy, therapeutic uses of medical radioisotopes, nuclear physics measurements and reactor safety studies. The work undertaken within the project included the following tasks: Detailed analyses and comparisons of the cross-section data and the related uncertainty information present in different reactor dosimetry and general purpose libraries, including IRDF-90.2, JENDL/D-99 and 2 RRDF-98, and the most recent releases of ENDF/B-VI, JEFF-3.0 and CENDL-2. Comparisons were also made of the calculated integral cross section data with experimental reaction rates in standard neutron fields; Selection of the best quality cross-section information based on the above comparisons; Evaluation and testing of new reaction cross-sections, as requested by the reactor dosimetry community for extension of the library; Selection of evaluated and up to date nuclear decay characteristics and isotopic abundances; Testing of important dosimetry cross-sections in reference benchmark neutron fields. Although the release of IRDF-2002 and publication of the related documentation occurred after 2002, participants attending the second Technical Meeting decided to retain the title IRDF-2002, since the library has been referred to as this in the open literature. A CD-ROM containing the full contents of IRDF-2002 accompanies this report. Updated versions of this library will also be released by the IAEA on CD-ROM (author)

  12. High sensitivity MOSFET-based neutron dosimetry

    International Nuclear Information System (INIS)

    Fragopoulou, M.; Konstantakos, V.; Zamani, M.; Siskos, S.; Laopoulos, T.; Sarrabayrouse, G.

    2010-01-01

    A new dosemeter based on a metal-oxide-semiconductor field effect transistor sensitive to both neutrons and gamma radiation was manufactured at LAAS-CNRS Laboratory, Toulouse, France. In order to be used for neutron dosimetry, a thin film of lithium fluoride was deposited on the surface of the gate of the device. The characteristics of the dosemeter, such as the dependence of its response to neutron dose and dose rate, were investigated. The studied dosemeter was very sensitive to gamma rays compared to other dosemeters proposed in the literature. Its response in thermal neutrons was found to be much higher than in fast neutrons and gamma rays.

  13. Personnel dosimetry: specialized industrial services. Jan 1997-Aug 2001

    International Nuclear Information System (INIS)

    Guillen, J.A.

    2001-09-01

    The purpose of this report is to evaluate data from personnel dosimetry of the Servicios Industriales Especializados, that is a licensee with gamma sources for non destructive testing. Data of the period Jan-97 to Aug-01 are evaluated in terms of collective doses. This report was made according to the national regulations that stablish to control that annual limits and reference levels in personnel dosimetry must be controlled

  14. In-situ radiation dosimetry based on Radio-Fluorogenic Co-Polymerization

    NARCIS (Netherlands)

    Warman, J.M.; Luthjens, L.H.; De Haas, M.P.

    2009-01-01

    A fluorimetric method of radiation dosimetry is presented for which the intensity of the fluorescence of a (tissue equivalent) medium is linearly dependent on accumulated dose from a few Gray up to kiloGrays. The method is based on radio-fluorogenic co-polymerization (RFCP) in which a normally very

  15. Chemical dosimetry principles in high dose dosimetry

    International Nuclear Information System (INIS)

    Mhatre, Sachin G.V.

    2016-01-01

    In radiation processing, activities of principal concern are process validation and process control. The objective of such formalized procedures is to establish documentary evidence that the irradiation process has achieved the desired results. The key element of such activities is inevitably a well characterized reliable dosimetry system that is traceable to recognized national and international dosimetry standards. Only such dosimetry systems can help establish the required documentary evidence. In addition, industrial radiation processing such as irradiation of foodstuffs and sterilization of health careproducts are both highly regulated, in particular with regard to dose. Besides, dosimetry is necessary for scaling up processes from the research level to the industrial level. Thus, accurate dosimetry is indispensable

  16. Management system of personnel dosimetry based on ISO 9001:2008 for medical diagnostic

    International Nuclear Information System (INIS)

    Queiroz, Carlos E.B.; Gerber Junior, Walmoli; Jahn, Tiago R.; Hahn, Tiago T.; Fontana, Thiago S.; Bolzan, Vagner

    2013-01-01

    MDose is a computer management system of personal dosimetry in diagnostic radiology services physician based on ISO 9001:9008 management system. According to Brazilian law all service radiology should implement a control of personal dosimetry in addition to radiation doses greater than 1.5 mSv/year service should do research of high dose, which is to identify the causes the resulting dose increase professional. This work is based on the use of the PDCA cycle in a JAVA software developed as a management method in the analysis of high doses in order to promote systematic and continuous improvement within the organization of radiological protection of workers

  17. Dose measurements in dental radiology using thermoluminescent dosimetry

    International Nuclear Information System (INIS)

    Chiara, Ana Claudia M. de; Costa, Alessandro M.; Pardini, Luiz Carlos

    2009-01-01

    The aim of this work was the implementation of a code of practice for dosimetry in dental radiology using the technique of thermoluminescent dosimetry. General principles for the use of thermoluminescent dosimeters were followed. The irradiations were performed using ten X-ray equipment for intra-oral radiography and an X-ray equipment for panoramic radiography. The incident air kerma was evaluated for five different exposure times used in clinical practice for intra-oral radiographs. Using a backscatter factor of 1.2, it was observed that approximately 40% of the entrance skin dose values found for intra-oral radiographs are above the diagnostic reference level recommended in national regulation. Different configurations of voltage and current were used representing the exposure as a child, woman and man for panoramic radiographs. The results obtained for the air kerma area product were respectively 53.3 +- 5.2 mGy.cm 2 , 101.5 +- 9.5 mGy.cm 2 and 116.8 +- 10.4 mGy.cm 2 . The use of thermoluminescent dosimetry requires several procedures before a result is recorded. The use of dosimeters with ionization chambers or semiconductors provides a simple and robust method for routine measurements. However, the use of thermoluminescent dosimetry can be of great value to large-scale surveys to establish diagnostic reference levels. (author)

  18. Conductivity of alanine solution for high level dosimetry

    International Nuclear Information System (INIS)

    Wieser, A.; Figel, M.; Regulla, D.F.

    1993-01-01

    The amino acid alanine is well known as a dosimetric detector material for high level dosimetry. Its application is based on the formation of radicals by ionising radiation. The free radicals are earlier detected by electron spin resonance (ESR) spectroscopy or chemically after dissolving the irradiated samples. Of all these methods the ESR/alanine system is the most advanced and is suggested for reference dosimetry. At present, however, the high cost of the system is a serious handicap for a large scale routine application in radiation plants. In this study the variation of electrical conductivity of L-alanine solution with applied dose is investigated in the range from 0.5-200 kGy. The conductivity was measured with a 50 MHz RF oscillator. This readout method is uncomplicated and may be suitable for routine application. The experiments were performed with L-alanine solution in glass ampoules. (Author)

  19. Stability of reference class ionization chambers used for radiotherapy dosimetry: IAEA experience

    International Nuclear Information System (INIS)

    Czap, L.; Meghzifene, A.; Shortt, K.R.; Andreo, P.

    2002-01-01

    The IAEA calibrates ionization chambers, used in radiotherapy, for its Member States. The calibrations are either for Secondary Standards Dosimetry Laboratories (SSDLs) or hospitals from countries without a SSDL. For that purpose, the IAEA calibrates mainly reference class instruments that are in turn used to cross-calibrate field class instruments at the hospital. Typically, the IAEA calibrates about 30-40 ionization chambers per year, of which about half are new chambers purchased by the IAEA for its Member States using Technical Cooperation funds. The IAEA database includes the calibration coefficients of 189 reference class ionization chambers of the following types: NE-2561/2611, NE-2571, W-30001/W-30010. The results of the calibrations and recalibrations of the ionization chambers in terms of air kerma and absorbed dose to water are presented and discussed. The ratio of 60 Co calibration coefficients N D,w /N K , labelled C K , was determined for all chambers. The use of C K as a chamber dependent parameter and quality control indicator to check the results of the routine IAEA calibrations is discussed. In the process of its routine calibrations, the IAEA identified a specific problem related to the W- 30001 ionization chambers. The stability of these chambers was found to exceed the 0.5% tolerance limit set by the International IEC standard. Other SSDLs reported similar findings. The manufacturer stopped the production of these W-30001 chambers to investigate the reasons for this anomalous behaviour. After identifying and correcting the problem, the manufacturer produced a new type of ionization chamber. Five of these chambers were tested at the IAEA and found to be within the tolerance limit

  20. A Chinese Visible Human-based computational female pelvic phantom for radiation dosimetry simulation

    International Nuclear Information System (INIS)

    Nan, H.; Jinlu, S.; Shaoxiang, Z.; Qing, H.; Li-wen, T.; Chengjun, G.; Tang, X.; Jiang, S. B.; Xiano-lin, Z.

    2010-01-01

    Accurate voxel phantom is needed for dosimetric simulation in radiation therapy for malignant tumors in female pelvic region. However, most of the existing voxel phantoms are constructed on the basis of Caucasian or non-Chinese population. Materials and Methods: A computational framework for constructing female pelvic voxel phantom for radiation dosimetry was performed based on Chinese Visible Human datasets. First, several organs within pelvic region were segmented from Chinese Visible Human datasets. Then, polygonization and voxelization were performed based on the segmented organs and a 3D computational phantom is built in the form of a set of voxel arrays. Results: The generated phantom can be converted and loaded into treatment planning system for radiation dosimetry calculation. From the observed dosimetric results of those organs and structures, we can evaluate their absorbed dose and implement some simulation studies. Conclusion: A voxel female pelvic phantom was developed from Chinese Visible Human datasets. It can be utilized for dosimetry evaluation and planning simulation, which would be very helpful to improve the clinical performance and reduce the radiation toxicity on organ at risk.

  1. A nephron-based model of the kidneys for macro-to-micro α-particle dosimetry

    Science.gov (United States)

    Hobbs, Robert F.; Song, Hong; Huso, David L.; Sundel, Margaret H.; Sgouros, George

    2012-07-01

    Targeted α-particle therapy is a promising treatment modality for cancer. Due to the short path-length of α-particles, the potential efficacy and toxicity of these agents is best evaluated by microscale dosimetry calculations instead of whole-organ, absorbed fraction-based dosimetry. Yet time-integrated activity (TIA), the necessary input for dosimetry, can still only be quantified reliably at the organ or macroscopic level. We describe a nephron- and cellular-based kidney dosimetry model for α-particle radiopharmaceutical therapy, more suited to the short range and high linear energy transfer of α-particle emitters, which takes as input kidney or cortex TIA and through a macro to micro model-based methodology assigns TIA to micro-level kidney substructures. We apply a geometrical model to provide nephron-level S-values for a range of isotopes allowing for pre-clinical and clinical applications according to the medical internal radiation dosimetry (MIRD) schema. We assume that the relationship between whole-organ TIA and TIA apportioned to microscale substructures as measured in an appropriate pre-clinical mammalian model also applies to the human. In both, the pre-clinical and the human model, microscale substructures are described as a collection of simple geometrical shapes akin to those used in the Cristy-Eckerman phantoms for normal organs. Anatomical parameters are taken from the literature for a human model, while murine parameters are measured ex vivo. The murine histological slides also provide the data for volume of occupancy of the different compartments of the nephron in the kidney: glomerulus versus proximal tubule versus distal tubule. Monte Carlo simulations are run with activity placed in the different nephron compartments for several α-particle emitters currently under investigation in radiopharmaceutical therapy. The S-values were calculated for the α-emitters and their descendants between the different nephron compartments for both the

  2. A nephron-based model of the kidneys for macro-to-micro α-particle dosimetry

    International Nuclear Information System (INIS)

    Hobbs, Robert F; Song Hong; H Sundel, Margaret; Sgouros, George; Huso, David L

    2012-01-01

    Targeted α-particle therapy is a promising treatment modality for cancer. Due to the short path-length of α-particles, the potential efficacy and toxicity of these agents is best evaluated by microscale dosimetry calculations instead of whole-organ, absorbed fraction-based dosimetry. Yet time-integrated activity (TIA), the necessary input for dosimetry, can still only be quantified reliably at the organ or macroscopic level. We describe a nephron- and cellular-based kidney dosimetry model for α-particle radiopharmaceutical therapy, more suited to the short range and high linear energy transfer of α-particle emitters, which takes as input kidney or cortex TIA and through a macro to micro model-based methodology assigns TIA to micro-level kidney substructures. We apply a geometrical model to provide nephron-level S-values for a range of isotopes allowing for pre-clinical and clinical applications according to the medical internal radiation dosimetry (MIRD) schema. We assume that the relationship between whole-organ TIA and TIA apportioned to microscale substructures as measured in an appropriate pre-clinical mammalian model also applies to the human. In both, the pre-clinical and the human model, microscale substructures are described as a collection of simple geometrical shapes akin to those used in the Cristy–Eckerman phantoms for normal organs. Anatomical parameters are taken from the literature for a human model, while murine parameters are measured ex vivo. The murine histological slides also provide the data for volume of occupancy of the different compartments of the nephron in the kidney: glomerulus versus proximal tubule versus distal tubule. Monte Carlo simulations are run with activity placed in the different nephron compartments for several α-particle emitters currently under investigation in radiopharmaceutical therapy. The S-values were calculated for the α-emitters and their descendants between the different nephron compartments for both the

  3. 100 years of solid state dosimetry and radiation protection dosimetry

    International Nuclear Information System (INIS)

    Bartlett, David T.

    2008-01-01

    The use of solid state detectors in radiation dosimetry has passed its 100th anniversary. The major applications of these detectors in radiation dosimetry have been in personal dosimetry, retrospective dosimetry, dating, medical dosimetry, the characterization of radiation fields, and also in microdosimetry and radiobiology research. In this introductory paper for the 15th International Conference, I shall speak of the history of solid state dosimetry and of the radiation measurement quantities that developed at the same time, mention some landmark developments in detectors and applications, speak a bit more about dosimetry and measurement quantities, and briefly look at the past and future

  4. An image-based skeletal dosimetry model for the ICRP reference newborn-internal electron sources

    International Nuclear Information System (INIS)

    Pafundi, Deanna; Lee, Choonsik; Bolch, Wesley; Rajon, Didier; Jokisch, Derek

    2010-01-01

    In this study, a comprehensive electron dosimetry model of newborn skeletal tissues is presented. The model is constructed using the University of Florida newborn hybrid phantom of Lee et al (2007 Phys. Med. Biol. 52 3309-33), the newborn skeletal tissue model of Pafundi et al (2009 Phys. Med. Biol. 54 4497-531) and the EGSnrc-based Paired Image Radiation Transport code of Shah et al (2005 J. Nucl. Med. 46 344-53). Target tissues include the active bone marrow (surrogate tissue for hematopoietic stem cells), shallow marrow (surrogate tissue for osteoprogenitor cells) and unossified cartilage (surrogate tissue for chondrocytes). Monoenergetic electron emissions are considered over the energy range 1 keV to 10 MeV for the following source tissues: active marrow, trabecular bone (surfaces and volumes), cortical bone (surfaces and volumes) and cartilage. Transport results are reported as specific absorbed fractions according to the MIRD schema and are given as skeletal-averaged values in the paper with bone-specific values reported in both tabular and graphic format as electronic annexes (supplementary data). The method utilized in this work uniquely includes (1) explicit accounting for the finite size and shape of newborn ossification centers (spongiosa regions), (2) explicit accounting for active and shallow marrow dose from electron emissions in cortical bone as well as sites of unossified cartilage, (3) proper accounting of the distribution of trabecular and cortical volumes and surfaces in the newborn skeleton when considering mineral bone sources and (4) explicit consideration of the marrow cellularity changes for active marrow self-irradiation as applicable to radionuclide therapy of diseased marrow in the newborn child.

  5. An image-based skeletal dosimetry model for the ICRP reference newborn-internal electron sources

    Energy Technology Data Exchange (ETDEWEB)

    Pafundi, Deanna; Lee, Choonsik; Bolch, Wesley [Department of Nuclear and Radiological Engineering, University of Florida, Gainesville, FL (United States); Rajon, Didier [Department of Neurosurgery, University of Florida, Gainesville, FL (United States); Jokisch, Derek [Department of Physics and Astronomy, Francis Marion University, Florence, SC (United States)], E-mail: wbolch@ufl.edu

    2010-04-07

    In this study, a comprehensive electron dosimetry model of newborn skeletal tissues is presented. The model is constructed using the University of Florida newborn hybrid phantom of Lee et al (2007 Phys. Med. Biol. 52 3309-33), the newborn skeletal tissue model of Pafundi et al (2009 Phys. Med. Biol. 54 4497-531) and the EGSnrc-based Paired Image Radiation Transport code of Shah et al (2005 J. Nucl. Med. 46 344-53). Target tissues include the active bone marrow (surrogate tissue for hematopoietic stem cells), shallow marrow (surrogate tissue for osteoprogenitor cells) and unossified cartilage (surrogate tissue for chondrocytes). Monoenergetic electron emissions are considered over the energy range 1 keV to 10 MeV for the following source tissues: active marrow, trabecular bone (surfaces and volumes), cortical bone (surfaces and volumes) and cartilage. Transport results are reported as specific absorbed fractions according to the MIRD schema and are given as skeletal-averaged values in the paper with bone-specific values reported in both tabular and graphic format as electronic annexes (supplementary data). The method utilized in this work uniquely includes (1) explicit accounting for the finite size and shape of newborn ossification centers (spongiosa regions), (2) explicit accounting for active and shallow marrow dose from electron emissions in cortical bone as well as sites of unossified cartilage, (3) proper accounting of the distribution of trabecular and cortical volumes and surfaces in the newborn skeleton when considering mineral bone sources and (4) explicit consideration of the marrow cellularity changes for active marrow self-irradiation as applicable to radionuclide therapy of diseased marrow in the newborn child.

  6. Clinical application of in vivo dosimetry for external telecobalt machine

    International Nuclear Information System (INIS)

    Mohammed, H. H. M.

    2011-01-01

    In external beam radiotherapy quality assurance is carried out on the individual components of treatment chain. The patient simulating device, planning system and treatment machine are tested regularly according to set protocols developed by national and international organizations. Even thought these individual systems are not tested for errors which can be made in the transfer between the systems. The best quality assurance for the treatment planning chain. In vivo dosimetry is used as a quality assurance tool for verifying dosimetry as either the entrance or exit surface of the patient undergoing external beam radiotherapy. It is a proven reliable method of checking overall treatment accuracy, allowing verification of dosimetry and dose calculation as well as patient treatment setup. Accurate in vivo dosimetry is carried out if diodes and thermoluminescence dosimeters (TLDs). the main detector types in use for in vivo dosimetry, are carefully calibrated and the factors influencing their sensitivity are taken into account. The aim of this study was to verify the response of TLDs type (LiF: Mg, Cu, p) use in radiotherapy, to establish calibration procedure for TLDs and to evaluate entrance dose obtained by the treatment planning system with measured dose using thermoluminescence detectors. Calibration of TLDs was done using Cobalt-60 teletherapy machine, linearity and calibration factors were determined. Measurements were performed in random phantom for breast irradiation (for the breast irradiation ( For the breast irradiation technique considered, wedge field was used). All TLDs were processed and analyzed at RICK. In vivo dosimetry represents a technique that has been widely employed to evaluate the dose to the patient mainly in radiotherapy. Thermoluminescent dosimeters are considered the gold stander for in vivo dosimetry and do not require cables for measurements which makes them ideal for mail based studies and have no dose rate or temperature dependence

  7. An absorbed dose calorimeter for IMRT dosimetry

    International Nuclear Information System (INIS)

    Duane, S.; Aldehaybes, M.; Bailey, M.; Lee, N.D.; Thomas, C.G.; Palmans, H.

    2012-01-01

    A new calorimeter for dosimetry in small and complex fields has been built. The device is intended for the direct determination of absorbed dose to water in moderately small fields and in composite fields such as IMRT treatments, and as a transfer instrument calibrated against existing absorbed dose standards in conventional reference conditions. The geometry, materials and mode of operation have been chosen to minimize detector perturbations when used in a water phantom, to give a reasonably isotropic response and to minimize the effects of heat transfer when the calorimeter is used in non-reference conditions in a water phantom. The size of the core is meant to meet the needs of measurement in IMRT treatments and is comparable to the size of the air cavity in a type NE2611 ionization chamber. The calorimeter may also be used for small field dosimetry. Initial measurements in reference conditions and in an IMRT head and neck plan, collapsed to gantry angle zero, have been made to estimate the thermal characteristics of the device, and to assess its performance in use. The standard deviation (estimated repeatability) of the reference absorbed dose measurements was 0.02 Gy (0.6%). (authors)

  8. Internal dosimetry, past and future

    International Nuclear Information System (INIS)

    Johnson, J.R.

    1989-03-01

    This paper is a review of the progress in the dosimetry of internally deposited radionuclides (internal dosimetry) since World War II. Previous to that, only naturally occurring radionuclides were available and only a limited number of studies of biokinetics and dosimetry were done. The main radionuclides studied were 226 Ra, 228 Ra, and 224 Ra but natural uranium was also studied mainly because of its toxic effect as a heavy metal, and not because it was radioactive. The effects of 226 Ra in bone, mainly from the radium dial painters, also formed the only bases for the radiotoxicity of radionuclides in bone for many years, and it is still, along with 224 Ra, the main source of information on the effects of alpha emitters in bone. The publications of the International Commission on Radiological Protection that have an impact on internal dosimetry are used as mileposts for this review. These series of publications, more than any other, represent a broad consensus of opinion within the radiation protection community at the time of their publication, and have formed the bases for radiation protection practice throughout the world. This review is not meant to be exhaustive; it is meant to be a personnel view of the evolution of internal dosimetry, and to present the author's opinion of what the future directions in internal dosimetry will be. 39 refs., 2 tabs

  9. Development of 3D Slicer based film dosimetry analysis

    International Nuclear Information System (INIS)

    Alexander, K M; Schreiner, L J; Robinson, A; Pinter, C; Fichtinger, G

    2017-01-01

    Radiochromic film dosimetry has been widely adopted in the clinic as it is a convenient option for dose measurement and verification. Film dosimetry analysis is typically performed using expensive commercial software, or custom made scripts in Matlab. However, common clinical film analysis software is not transparent regarding what corrections/optimizations are running behind the scenes. In this work, an extension to the open-source medical imaging platform 3D Slicer was developed and implemented in our centre for film dosimetry analysis. This extension streamlines importing treatment planning system dose and film imaging data, film calibration, registration, and comparison of 2D dose distributions, enabling greater accessibility to film analysis and higher reliability. (paper)

  10. Sandia National Laboratories Internal Dosimetry Technical Basis Manual (Rev 4)

    Energy Technology Data Exchange (ETDEWEB)

    Goke, Sarah Hayes [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Elliott, Nathan Ryan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-09-01

    The Sandia National Laboratories’ Internal Dosimetry Technical Basis Manual is intended to provide extended technical discussion and justification of the internal dosimetry program at SNL. It serves to record the approach to evaluating internal doses from radiobioassay data, and where appropriate, from workplace monitoring data per the Department of Energy Internal Dosimetry Program Guide DOE G 441.1C. The discussion contained herein is directed primarily to current and future SNL internal dosimetrists. In an effort to conserve space in the TBM and avoid duplication, it contains numerous references providing an entry point into the internal dosimetry literature relevant to this program. The TBM is not intended to act as a policy or procedure statement, but will supplement the information normally found in procedures or policy documents. The internal dosimetry program outlined in this manual is intended to meet the requirements of Federal Rule 10CFR835 for monitoring the workplace and for assessing internal radiation doses to workers.

  11. Chinese reference human voxel phantoms for radiation protection: development, application and recent progress

    International Nuclear Information System (INIS)

    Pan Yuxi; Qiu Rui; Ren Li; Zhu Huanjun; Li Junli; Liu Liye

    2014-01-01

    This paper presents the work of constructing Chinese reference human voxel phantoms, taking Chinese reference adult female voxel model for example. In this study, a site-specific skeleton structure was built, some radiation sensitive organs were supplemented. Organ sub-segmentation was taken into account. The constructed phantoms include almost all radiation sensitive organs required by ICRP new recommendation. Masses of the organs are almost consistent with the Chinese reference data within 5%. The Chinese reference human phantoms have been applied both in internal dosimetry and external dosimetry. The results provide fundamental data for Chinese radiation dosimetry. In addition, the newly established detailed breast model and micro-bone model were introduced. (authors)

  12. Dosimetry optimization at COGEMA-La Hague

    International Nuclear Information System (INIS)

    Kalimbadjian, J.

    2000-01-01

    At the present time, the la Hague site strives to apply international recommendations together with national regulations concerning radiation protection, and especially the respect of limitation and optimization principles. The application of these principles is based on the implementation of a passive dosimetry and an active dosimetry. The monthly passive dosimetry is monitored by means of a photographic dosimetry film, completed with lithium fluorine thermoluminescent film badges. This personal dosimetry common to X, β, γ and neutron radiations is carried out in close relationship between the Radiation Protection Department, the Occupational Medical Department and the staff running the Plant. The application or ALARA's principle as well as that of radiation protection optimization implies to implement a complementary active dosimetry enabling to gain in real time, the personal dosimetry of each intervening person, either they be COGEMA's workers or external companies'. This active dosimetry provides with following information: This preventive dosimetry is based on the knowledge of doses integration in real time and is fitted with alarm thresholds according to the total amount of doses and dose rates. Thresholds on the dose rate are also set relatively to the radiological environment. This knowledge of doses and dose rates allows a stricter management of the works, while analyzing them according to the nature of the work, to the location and to the skills of the intervening people. This dosimetry allows to analyze and optimize doses integration according to the works nature for the whole intervening staff. The la Hague Site has developed an active personal dosimetry system, common to every intervening person, COGEMA or external companies. The DOSICARD was thus elaborated, shaped as an electronic dosimeter fitted with an alarm and a smart card. The access to controlled areas is conditioned to information given by the DOSICARD concerning medical aptitudes and

  13. SU-E-T-66: A Prototype for Couch Based Real-Time Dosimetry in External Beam Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Ramachandran, P [Peter MacCallum Cancer Centre, Bendigo (Australia)

    2015-06-15

    Purpose: The main purpose of this study is to design a prototype for couch-based based real time dosimetry system in external beam radiotherapy Methods: A prototype of 100 ionization chambers was designed on a printed circuit board by etching the copper layer and each ionization chamber was wired to a 50 pin connector. The signals from the two 50 pin connectors collected from the ionization chambers were then transferred to a PXI module from National Instruments. The PXI module houses a current amplifier that amplifies the charge collected from the ionization chamber. The amplified signal is then sent to a digital multimeter module for converting the analog signal to digital signal. A software was designed in labview to read and display the signals obtained from the PXI module. A couch attachment frame was designed to house the 100 ionization chamber module. The frame was fixed underneath the treatment couch for measuring the dose during treatment. Resutls: The ionization chamber based prototype dosimetry was tested for simple radiotherapy treatment fields and found to be a useful device for measuring real time dosimetry at the treatment couch plane. This information could be used to assess the delivered dose to a patient during radiotherapy. It could be used as an invivo dosimeter during radiotherapy. Conclusion: In this study, a prototype for couch based real time dosimetry system was designed and tested. The prototype forms a basis for the development of large scale couch based real time dosimetry system that could be used to perform morning QA prior to treatment, assess real time doses delivered to patient and as a device to monitor the output of the treatment beam. Peter MacCallum Cancer Foundation.

  14. SU-E-T-66: A Prototype for Couch Based Real-Time Dosimetry in External Beam Radiotherapy

    International Nuclear Information System (INIS)

    Ramachandran, P

    2015-01-01

    Purpose: The main purpose of this study is to design a prototype for couch-based based real time dosimetry system in external beam radiotherapy Methods: A prototype of 100 ionization chambers was designed on a printed circuit board by etching the copper layer and each ionization chamber was wired to a 50 pin connector. The signals from the two 50 pin connectors collected from the ionization chambers were then transferred to a PXI module from National Instruments. The PXI module houses a current amplifier that amplifies the charge collected from the ionization chamber. The amplified signal is then sent to a digital multimeter module for converting the analog signal to digital signal. A software was designed in labview to read and display the signals obtained from the PXI module. A couch attachment frame was designed to house the 100 ionization chamber module. The frame was fixed underneath the treatment couch for measuring the dose during treatment. Resutls: The ionization chamber based prototype dosimetry was tested for simple radiotherapy treatment fields and found to be a useful device for measuring real time dosimetry at the treatment couch plane. This information could be used to assess the delivered dose to a patient during radiotherapy. It could be used as an invivo dosimeter during radiotherapy. Conclusion: In this study, a prototype for couch based real time dosimetry system was designed and tested. The prototype forms a basis for the development of large scale couch based real time dosimetry system that could be used to perform morning QA prior to treatment, assess real time doses delivered to patient and as a device to monitor the output of the treatment beam. Peter MacCallum Cancer Foundation

  15. Reassessment of the atomic bomb radiation dosimetry for Hiroshima and Nagasaki. Dosimetry system 2002. DS02. Volume 1

    International Nuclear Information System (INIS)

    Young, Robert W.; Kerr, George D.

    2005-01-01

    The extensive efforts to review the dosimetry of the atomic-bomb survivors and formulate the new dosimetry system DS02 have been greatly welcomed by the Radiation Effects Research Foundation (RERF). This accomplishment is a fine tribute to the importance of the epidemiological studies being conducted at RERF. No other study is so informative of the effects of radiation on human health. The gracious participation in the RERF program by the atomic-bomb survivors allows us to contribute to the well being of these individuals, and the high quality of the data obtained allows the RERF results to feature so prominently in the formulation of international guidelines for radiation protection. Such a great effort to improve and substantiate the dosimetry would not otherwise have been justified. RERF greatly appreciates the independent work of the U.S. and Japanese Working Groups on the atomic-bomb dosimetry and the review by the Joint Senior Review Group of this overall effort. We are assured that unbiased development of the new dosimetry system will reflect well in its application in the RERF epidemiology study. The documentation included in this report will serve as reference for the many deliberations concluded. The title publications are divided into 2 volumes. This is the first volume. The 8 of the reports in each chapter are indexed individually. (J.P.N.)

  16. Reassessment of the atomic bomb radiation dosimetry for Hiroshima and Nagasaki. Dosimetry system 2002. DS02. Volume 2

    International Nuclear Information System (INIS)

    Young, Robert W.; Kerr, George D.

    2005-01-01

    The extensive efforts to review the dosimetry of the atomic-bomb survivors and formulate the new dosimetry system DS02 have been greatly welcomed by the Radiation Effects Research Foundation (RERF). This accomplishment is a fine tribute to the importance of the epidemiological studies being conducted at RERF. No other study is so informative of the effects of radiation on human health. The gracious participation in the RERF program by the atomic-bomb survivors allows us to contribute to the well being of these individuals, and the high quality of the data obtained allows the RERF results to feature so prominently in the formulation of international guidelines for radiation protection. Such a great effort to improve and substantiate the dosimetry would not otherwise have been justified. RERF greatly appreciates the independent work of the U.S. and Japanese Working Groups on the atomic-bomb dosimetry and the review by the Joint Senior Review Group of this overall effort. We are assured that unbiased development of the new dosimetry system will reflect well in its application in the RERF epidemiology study. The documentation included in this report will serve as reference for the many deliberations concluded. The title publications are divided into 2 volumes. This is the second volume. The 29 of the reports in each chapter are indexed individually. (J.P.N.)

  17. Advantages and disadvantages of luminescence dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Olko, Pawel, E-mail: Pawel.Olko@ifj.edu.p [Institute of Nuclear Physics Polish Academy of Science (IFJ PAN), Krakow (Poland)

    2010-03-15

    Owing to their excellent dosimetric properties, luminescence detectors of ionizing radiation are now extensively applied in individual dosimetry services. The most frequently used personal dosemeters are based on Optically Stimulated Luminescence (OSL), radiophotoluminescence (RPL) or thermoluminescence (TL). Luminescence detectors have also found several applications in clinical dosimetry, especially around new radiation modalities in radiotherapy, such as Intensity Modulated Radiotherapy (IMRT) or ion beam radiotherapy. Requirements of luminescence detectors applied in individual and clinical dosimetry and some recent developments in luminescence of detectors and techniques leading to significant improvements of the functionality and accuracy of dosimetry systems are reviewed and discussed.

  18. Photon dosimetry intercomparisons at Tygerberg and Groote Schuur hospitals

    International Nuclear Information System (INIS)

    Jones, D.T.L.; Symons, J.E.; Schreuder, A.N.; Van der Merwe, E.J.; Rossouw, A.; Hough, J.K.; Lazarus, G.L.

    1994-08-01

    A national photon dosimetry intercomparison was undertaken at 8 hospitals at the beginning of 1989 prior to the commencement of randomised clinical trials involving neutron therapy at the National Accelerator Centre. The results obtained were in agreement at all but two hospitals. Following these studies it was agreed that a uniform photon dosimetry protocol, the AAPM TG2 protocol, be adopted countrywide. The clinical program at the National Accelerator Centre is now far advanced and it was deemed appropriate to undertake a new photon dosimetry intercomparison at two local hospitals, through which all patients are referred. The procedure involved was to compare the doses measured at each hospital under specified conditions by National Accelerator staff with the doses measured by the hospital physicists using their own equipment and protocols. The results obtained were in good agreement, confirming the validity of the dosimetry techniques used. 8 refs., 8 tabs

  19. Miniature semiconductor detectors for in vivo dosimetry

    International Nuclear Information System (INIS)

    Rosenfeld, A. B.; Cutajar, D.; Lerch, M. L. F.; Takacs, G.; Cornelius, I. M.; Yudelev, M.; Zaider, M.

    2006-01-01

    Silicon mini-semiconductor detectors are found in wide applications for in vivo personal dosimetry and dosimetry and Micro-dosimetry of different radiation oncology modalities. These applications are based on integral and spectroscopy modes of metal oxide semiconductor field effect transistor and silicon p-n junction detectors. The advantages and limitations of each are discussed. (authors)

  20. Verification of dosimetry cross sections above 10 MeV based on measurement of activation reaction rates in fission neutron field

    International Nuclear Information System (INIS)

    Odano, Naoteru; Miura, Toshimasa; Yamaji, Akio.

    1996-01-01

    To validate the dosimetry cross sections in fast neutron energy range, activation reaction rates were measured for 5 types of dosimetry cross sections which have sensitivity in the energy rage above 10 MeV utilizing JRR-4 reactor of JAERI. The measured reaction rates were compared with the calculations reaction rates by a continuous energy monte carlo code MVP. The calculated reaction rates were based on two dosimetry files, JENDL Dosimetry File and IRDF-90.2. (author)

  1. Advances in biomedical dosimetry

    International Nuclear Information System (INIS)

    1981-01-01

    quantity used in applied dosimetry. The problem is of enormous importance in medical dosimetry, because the refinement of radiotherapeutic techniques requires very accurate knowledge of the doses absorbed by the various tissues irradiated in the course of a treatment. - The use of fast neutron beams from cyclotrons in radiobiology and radiotherapy has also brought measurement problems, both in relation to the theoretical aspects and in relation to instrumentation. In this area users are in fact at more of a loss than the users of more conventional electron and photon beams, because there are virtually no reference scales as yet. Nevertheless, a highly active standardization programme is being pursued in the United States of America and in Europe among working groups set up by the medical physicists concerned. The studies undertaken in certain national laboratories should make it possible within a few years to set up a coherent dosimetric reference system adapted to this particularly complex sphere. - As far as international co-operation is concerned, efforts are being continued on behalf of the developing countries. The IAEA and WHO have set up a worldwide network of Secondary Standard Dosimetry Laboratories; the importance of these was stressed, and the national laboratories of the industrialized countries were urged to take an even more active part than heretofore in the operations of the network. (author)

  2. Dosimetry of radiolabeled monoclonal antibodies used for therapy

    International Nuclear Information System (INIS)

    Myers, M.J.; Hooker, G.R.; Epenetos, A.A.

    1986-01-01

    The present state of radiotherapy using labeled antibodies is reviewed. From the point of view of dosimetry, antibody therapy does not seem to have reached a stable and practicable enough state to provide an input to any but rather tentative dosimetry models. These, therefore, should not be taken too far until the problems of antibody targeting have been more fully developed. Some of the instrumental techniques for acquiring dosimetric data under clinical conditions are discussed as are some of the techniques of therapy in use today. 8 references, 3 figures

  3. The future of new calculation concepts in dosimetry based on the Monte Carlo Methods

    International Nuclear Information System (INIS)

    Makovicka, L.; Vasseur, A.; Sauget, M.; Martin, E.; Gschwind, R.; Henriet, J.; Vasseur, A.; Sauget, M.; Martin, E.; Gschwind, R.; Henriet, J.; Salomon, M.

    2009-01-01

    Monte Carlo codes, precise but slow, are very important tools in the vast majority of specialities connected to Radiation Physics, Radiation Protection and Dosimetry. A discussion about some other computing solutions is carried out; solutions not only based on the enhancement of computer power, or on the 'biasing'used for relative acceleration of these codes (in the case of photons), but on more efficient methods (A.N.N. - artificial neural network, C.B.R. - case-based reasoning - or other computer science techniques) already and successfully used for a long time in other scientific or industrial applications and not only Radiation Protection or Medical Dosimetry. (authors)

  4. Dosimetry Service

    CERN Multimedia

    2006-01-01

    Cern Staff and Users can now consult their dose records for an individual or an organizational unit with HRT. Please see more information on our web page: http://cern.ch/rp-dosimetry Dosimetry Service is open every morning from 8.30 - 12.00. Closed in the afternoons. We would like to remind you that dosimeters cannot be sent to customers by internal mail. Short-term dosimeters (VCT's) must always be returned to the Service after the use and must not be left on the racks in the experimental areas or in the secretariats. Dosimetry Service Tel. 7 2155 Dosimetry.service@cern.ch http://cern.ch/rp-dosimetry

  5. TH-CD-BRA-10: Towards Reference Dosimetry of MR-Linacs Using a Clinical Probe-Format Calorimeter

    Energy Technology Data Exchange (ETDEWEB)

    Renaud, J; Seuntjens, J [McGill University, Montreal, QC (Canada); Sarfehnia, A [McGill University, Montreal, QC (Canada); Sunnybrook Health Sciences Centre, Toronto, ON (Canada); Woodings, S; Kok, J; Asselen, B van; Wolthaus, J; Raaymakers, B [University Medical Center Utrecht, Utrecht (Netherlands)

    2016-06-15

    Purpose: To evaluate the influence of a 1.5 T magnetic field (B-field) on the response of a small-scale graphite calorimeter probe (GPC) developed for use as a novel clinical reference dosimeter. Characterization of the GPC was also assessed in a hybrid MRI-linac (MRL) clinical prototype by performing absolute dosimetry in multiple detector orientations. Methods: B-field influence was characterized using a variable-strength electromagnet system located 280 cm from the source of a clinical linac. The GPC was used to perform a total of 160 absolute dose measurements (6 MV, 920 MU/min) in a water phantom placed between the poles of the electromagnet. The magnitude of the B-field between the poles was varied in the range of 0 – 1.5 T. The relative response of the GPC was determined and compared to that of a thimble type ionization chamber (Exradin A1SL, Standard Imaging). Next, 65 dose measurements were performed using the GPC in a clinical MRL field (7 MV, 620 MU/min) to quantify the rotational dependence of the detector in the presence of a 1.5 T B-field. The GPC was rotated in steps of 90° inside a graphite phantom (SSD 140 cm, depth 2.5 cm) for two detector orientations (parallel and perpendicular to the B field). Results: Relative to the zero B-field condition, the A1SL chamber exhibited an average overresponse of +1.2 % ± 0.03 % at a B-field of 1.5 T, while the GPC under-responded on average by −0.5 % ± 0.9 %. For the MRL measurements, no significant differences were observed between the parallel and perpendicular orientations. In both cases, a rotational dependence of approximately ±1 % was measured. Conclusion: This work suggests that the B-field has minimal influence on the response of the GPC, making it a potentially attractive solution for clinical MRL reference dosimetry. This work has been supported in part by the CREATE Medical Physics Research Training Network NSERC grant RGPIN 432290, as well as NSERC grants RGPIN 298191 & 435608. JR is a

  6. International Standardization of the Clinical Dosimetry of Beta Radiation Brachytherapy Sources: Progress of an ISO Standard

    Science.gov (United States)

    Soares, Christopher

    2006-03-01

    In 2004 a new work item proposal (NWIP) was accepted by the International Organization for Standardization (ISO) Technical Committee 85 (TC85 -- Nuclear Energy), Subcommittee 2 (Radiation Protection) for the development of a standard for the clinical dosimetry of beta radiation sources used for brachytherapy. To develop this standard, a new Working Group (WG 22 - Ionizing Radiation Dosimetry and Protocols in Medical Applications) was formed. The standard is based on the work of an ad-hoc working group initiated by the Dosimetry task group of the Deutsches Insitiut für Normung (DIN). Initially the work was geared mainly towards the needs of intravascular brachytherapy, but with the decline of this application, more focus has been placed on the challenges of accurate dosimetry for the concave eye plaques used to treat ocular melanoma. Guidance is given for dosimetry formalisms, reference data to be used, calibrations, measurement methods, modeling, uncertainty determinations, treatment planning and reporting, and clinical quality control. The document is currently undergoing review by the ISO member bodies for acceptance as a Committee Draft (CD) with publication of the final standard expected by 2007. There are opportunities for other ISO standards for medical dosimetry within the framework of WG22.

  7. Decomposition of spectra in EPR dosimetry using the matrix method

    International Nuclear Information System (INIS)

    Sholom, S.V.; Chumak, V.V.

    2003-01-01

    The matrix method of EPR spectra decomposition is developed and adapted for routine application in retrospective EPR dosimetry with teeth. According to this method, the initial EPR spectra are decomposed (using methods of matrix algebra) into several reference components (reference matrices) that are specific for each material. Proposed procedure has been tested on the example of tooth enamel. Reference spectra were a spectrum of an empty sample tube and three standard signals of enamel (two at g=2.0045, both for the native signal and one at g perpendicular =2.0018, g parallel =1.9973 for the dosimetric signal). Values of dosimetric signals obtained using the given method have been compared with data obtained by manual manipulation of spectra, and good coincidence was observed. This allows considering the proposed method as potent for application in routine EPR dosimetry

  8. Comparison of IAEA protocols for clinical electron beam dosimetry

    International Nuclear Information System (INIS)

    Novotny, J.; Soukup, M.

    2002-01-01

    In most beam calibration protocols so far used in clinical practice, the method recommended for the determination of absorbed dose to water in high-energy electron beams is based on either an exposure or an air kerma calibration factor of an ionisation chamber in a C0 60 gamma-ray or 2 MV x-ray beam. These protocols are complex and the overall uncertainty in the absorbed dose to water under reference conditions is about 3-4%. The new generation of protocols, namely IAEA TRS 398, are based on absorbed dose-to-water standards in photon beams from Co 60 and accelerator beams. The possible errors in absorbed dose determination in reference conditions in practical clinical dosimetry caused by replacement of TRS 277 and TRS 381 protocols for a new TRS 398 protocol were carefully studied for clinical electron beams in energy range 6-20 MeV. All measurements were performed on Varian CLINAC 2100 C linear accelerator. The electron beam energy ranged from 6 to 20 MeV. Basically three different detectors were used for measurements: PTW Roos plane-parallel ionization chamber, calibrated PTW 30002 Farmer type, ionization, Scanditronix electron diode detector. Measurements of central axis percentage depth doses were made by diode using Wellhoefer WP700 beam scanner in 40 cm x 40 cm x 50 cm water phantom. A reference chamber or semiconductor diode mounted on electron treatment cone was used to correct beam output variations for a chamber or diode measurements during scanning. Absolute dose measurements were carried out with Roos plane-parallel chamber connected to PTW UNIDOS electrometer always for preselected number of monitor units. In a new IAEA dosimetry protocol clinical reference dosimetry for electron beam is performed at depth of d ref = 0.6R 50 - 0.1 [cm] instead of d max as in previous ones. To check the stability of electron beams for energy and to establish d ref and standard deviation for reference depth position, the depth dose curves obtained during the quality

  9. On line CALDoseX: real time Monte Carlo calculation via Internet for dosimetry in radiodiagnostic

    International Nuclear Information System (INIS)

    Kramer, Richard; Cassola, Vagner Ferreira; Lira, Carlos Alberto Brayner de Oliveira; Khoury, Helen Jamil; Cavalcanti, Arthur; Lins, Rafael Dueire

    2011-01-01

    The CALDose X 4.1 is a software which uses thr MASH and FASH phantoms. Patient dosimetry with reference phantoms is limited because the results can be applied only for patients which possess the same body mass and right height that the reference phantom. In this paper, the dosimetry of patients for diagnostic with X ray was extended by using a series of 18 phantoms with defined gender, different body masses and heights, in order to cover the real anatomy of the patients. It is possible to calculate absorbed doses in organs and tissues by real time Monte Carlo dosimetry through the Internet through a dosimetric service called CALDose X on line

  10. Dosimetry in Radiology

    International Nuclear Information System (INIS)

    Andisco, D.; Blanco, S.; Buzzi, A.E

    2014-01-01

    The steady growth in the use of ionizing radiation in diagnostic imaging requires to maintain a proper management of patient’s dose. Dosimetry in Radiology is a difficult topic to address, but vital for proper estimation of the dose the patient is receiving. The awareness that every day is perceived in our country on these issues is the appropriate response to this problem. This article describes the main dosimetric units used and easily exemplifies doses in radiology through internationally known reference values. (authors) [es

  11. An approved personal dosimetry service based on an electronic dosimeter

    International Nuclear Information System (INIS)

    Marshall, T.O.; Bartlett, D.T.; Burgess, P.H.; Campbell, J.I.; Hill, C.E.; Pook, E.A.; Sandford, D.J.

    1991-01-01

    At the Second Conference on Radiation Protection and Dosimetry a paper was presented which, in part, announced the development of an electronic dosimeter to be undertaken in the UK by the National Radiological Protection Board (NRPB) and Siemens Plessey Controls Ltd. This dosimeter was to be of a standard suitable for use as the basis of an approved personal dosimetry service for photon and beta radiations. The project has progressed extremely well and dosimeters and readers are about to become commercially available. The system and the specification of the dosimeter are presented. The NRPB is in the process of applying for approval by the Health and Safety Executive (HSE) to operate as personal monitoring service based on this dosimeter. As part of the approval procedure the dosimeter is being type tested and is also undergoing an HSE performance test and wearer trials. The tests and the wearer trials are described and a summary of the results to date presented. The way in which the service will be organized and operated is described and a comparison is made between the running of the service and others based on passive dosimeters at NRPB

  12. Dosimetry with the scanned proton beam on the PSI gantry

    International Nuclear Information System (INIS)

    Coray, A.; Pedroni, E.; Boehringer, T.; Lin, S.; Lomax, T.; Goitein, G.

    2002-01-01

    Full text: The irradiation facility at PSI is designed for the treatment of deep seated tumours with a proton beam energy of up to 270 MeV. The spot scanning technique, which uses a proton pencil beam applied to the patient, is performed on a compact isocentric gantry. An optimal three-dimensional conformation of the dose distribution to the target volume can be realized. A fast steering system and a redundant interlock system are in operation. The dose delivery is controlled by a parallel plate transmission chamber, which is calibrated in terms of number of protons per monitor unit. The therapy planning is based on an empirical model, which takes into account attenuation of primary protons and losses outside the primary beam through secondary products. The therapy plan predicts an absolute dose. The calibration of the primary monitor is done using a reference thimble ionization chamber inside a homogeneous geometrical dose volume. The reference system is calibrated in a cobalt field at the national office of metrology in terms of absorbed dose to water. The dosimetry protocol used up to last year was based on the ICRU Report Nr. 59, we have switched to the IAEA Code of Practice starting this beam period. Data on the monitor calibration for various energies and using two different reference systems will be shown. The calibration of the beam monitor using a Faraday Cup in the static pencil beam results in a good agreement with the ionization chamber measurements, with a deviation of less than 1%. Following the daily setup of the machine, an extensive quality control and safety check of the whole system is performed. The daily dosimetry quality assurance program includes: measurement of dose rate and monitor ratios; check of the beam position monitors; measurement of a depth dose curve; dose measurement in a regular dose field. The doses measured daily in a regular scanned field show a standard deviation of about 1 %. Further daily checks results, which illustrate

  13. External dosimetry - Applications to radiation protection

    International Nuclear Information System (INIS)

    Faussot, Alain

    2011-01-01

    Dosimetry is the essential component of radiation protection. It allows to determine by calculation and measurement the absorbed dose value, i.e. the energy amounts deposited in matter by ionizing radiations. It deals also with the irradiation effects on living organisms and with their biological consequences. This reference book gathers all the necessary information to understand and master the external dosimetry and the metrology of ionizing radiations, from the effects of radiations to the calibration of radiation protection devices. The first part is devoted to physical dosimetry and allows to obtain in a rigorous manner the mathematical formalisms leading to the absorbed dose for different ionizing radiation fields. The second part presents the biological effects of ionizing radiations on living matter and the determination of a set of specific radiation protection concepts and data to express the 'risk' to develop a radio-induced cancer. The third part deals with the metrology of ionizing radiations through the standardized study of the methods used for the calibration of radiation protection equipments. Some practical exercises with their corrections are proposed at the end of each chapter

  14. Survey of international personnel radiation dosimetry programs

    International Nuclear Information System (INIS)

    Swaja, R.E.

    1985-04-01

    In September of 1983, a mail survey was conducted to determine the status of external personnel gamma and neutron radiation dosimetry programs at international agencies. A total of 130 agencies participated in this study including military, regulatory, university, hospital, laboratory, and utility facilities. Information concerning basic dosimeter types, calibration sources, calibration phantoms, corrections to dosimeter responses, evaluating agencies, dose equivalent reporting conventions, ranges of typical or expected dose equivalents, and degree of satisfaction with existing systems was obtained for the gamma and neutron personnel monitoring programs at responding agencies. Results of this survey indicate that to provide the best possible occupational radiation monitoring programs and to improve dosimetry accuracy in performance studies, facility dosimetrists, regulatory and standards agencies, and research laboratories must act within their areas of responsibility to become familiar with their radiation monitoring systems, establish common reporting guidelines and performance standards, and provide opportunities for dosimetry testing and evaluation. 14 references, 10 tables

  15. On multichannel film dosimetry with channel-independent perturbations

    International Nuclear Information System (INIS)

    Méndez, I.; Peterlin, P.; Hudej, R.; Strojnik, A.; Casar, B.

    2014-01-01

    Purpose: Different multichannel methods for film dosimetry have been proposed in the literature. Two of them are the weighted mean method and the method put forth byMicke et al. [“Multichannel film dosimetry with nonuniformity correction,” Med. Phys. 38, 2523–2534 (2011)] and Mayer et al. [“Enhanced dosimetry procedures and assessment for EBT2 radiochromic film,” Med. Phys. 39, 2147–2155 (2012)]. The purpose of this work was to compare their results and to develop a generalized channel-independent perturbations framework in which both methods enter as special cases. Methods: Four models of channel-independent perturbations were compared: weighted mean, Micke–Mayer method, uniform distribution, and truncated normal distribution. A closed-form formula to calculate film doses and the associated type B uncertainty for all four models was deduced. To evaluate the models, film dose distributions were compared with planned and measured dose distributions. At the same time, several elements of the dosimetry process were compared: film type EBT2 versus EBT3, different waiting-time windows, reflection mode versus transmission mode scanning, and planned versus measured dose distribution for film calibration and for γ-index analysis. The methods and the models described in this study are publicly accessible through IRISEU. Alpha 1.1 ( http://www.iriseu.com ). IRISEU. is a cloud computing web application for calibration and dosimetry of radiochromic films. Results: The truncated normal distribution model provided the best agreement between film and reference doses, both for calibration and γ-index verification, and proved itself superior to both the weighted mean model, which neglects correlations between the channels, and the Micke–Mayer model, whose accuracy depends on the properties of the sensitometric curves. With respect to the selection of dosimetry protocol, no significant differences were found between transmission and reflection mode scanning

  16. On multichannel film dosimetry with channel-independent perturbations

    Energy Technology Data Exchange (ETDEWEB)

    Méndez, I., E-mail: nmendez@onko-i.si; Peterlin, P.; Hudej, R.; Strojnik, A.; Casar, B. [Department of Medical Physics, Institute of Oncology Ljubljana, Zaloška cesta 2, Ljubljana 1000 (Slovenia)

    2014-01-15

    Purpose: Different multichannel methods for film dosimetry have been proposed in the literature. Two of them are the weighted mean method and the method put forth byMicke et al. [“Multichannel film dosimetry with nonuniformity correction,” Med. Phys. 38, 2523–2534 (2011)] and Mayer et al. [“Enhanced dosimetry procedures and assessment for EBT2 radiochromic film,” Med. Phys. 39, 2147–2155 (2012)]. The purpose of this work was to compare their results and to develop a generalized channel-independent perturbations framework in which both methods enter as special cases. Methods: Four models of channel-independent perturbations were compared: weighted mean, Micke–Mayer method, uniform distribution, and truncated normal distribution. A closed-form formula to calculate film doses and the associated type B uncertainty for all four models was deduced. To evaluate the models, film dose distributions were compared with planned and measured dose distributions. At the same time, several elements of the dosimetry process were compared: film type EBT2 versus EBT3, different waiting-time windows, reflection mode versus transmission mode scanning, and planned versus measured dose distribution for film calibration and for γ-index analysis. The methods and the models described in this study are publicly accessible through IRISEU. Alpha 1.1 ( http://www.iriseu.com ). IRISEU. is a cloud computing web application for calibration and dosimetry of radiochromic films. Results: The truncated normal distribution model provided the best agreement between film and reference doses, both for calibration and γ-index verification, and proved itself superior to both the weighted mean model, which neglects correlations between the channels, and the Micke–Mayer model, whose accuracy depends on the properties of the sensitometric curves. With respect to the selection of dosimetry protocol, no significant differences were found between transmission and reflection mode scanning

  17. Comparison of methods for individualized astronaut organ dosimetry: Morphometry-based phantom library versus body contour autoscaling of a reference phantom

    Science.gov (United States)

    Sands, Michelle M.; Borrego, David; Maynard, Matthew R.; Bahadori, Amir A.; Bolch, Wesley E.

    2017-11-01

    One of the hazards faced by space crew members in low-Earth orbit or in deep space is exposure to ionizing radiation. It has been shown previously that while differences in organ-specific and whole-body risk estimates due to body size variations are small for highly-penetrating galactic cosmic rays, large differences in these quantities can result from exposure to shorter-range trapped proton or solar particle event radiations. For this reason, it is desirable to use morphometrically accurate computational phantoms representing each astronaut for a risk analysis, especially in the case of a solar particle event. An algorithm was developed to automatically sculpt and scale the UF adult male and adult female hybrid reference phantom to the individual outer body contour of a given astronaut. This process begins with the creation of a laser-measured polygon mesh model of the astronaut's body contour. Using the auto-scaling program and selecting several anatomical landmarks, the UF adult male or female phantom is adjusted to match the laser-measured outer body contour of the astronaut. A dosimetry comparison study was conducted to compare the organ dose accuracy of both the autoscaled phantom and that based upon a height-weight matched phantom from the UF/NCI Computational Phantom Library. Monte Carlo methods were used to simulate the environment of the August 1972 and February 1956 solar particle events. Using a series of individual-specific voxel phantoms as a local benchmark standard, autoscaled phantom organ dose estimates were shown to provide a 1% and 10% improvement in organ dose accuracy for a population of females and males, respectively, as compared to organ doses derived from height-weight matched phantoms from the UF/NCI Computational Phantom Library. In addition, this slight improvement in organ dose accuracy from the autoscaled phantoms is accompanied by reduced computer storage requirements and a more rapid method for individualized phantom generation

  18. SU-E-T-345: Validation of a Patient-Specific Monte Carlo Targeted Radionuclide Therapy Dosimetry Platform

    International Nuclear Information System (INIS)

    Besemer, A; Bednarz, B

    2014-01-01

    Purpose: There is a compelling need for personalized dosimetry in targeted radionuclide therapy given that conventional dose calculation methods fail to accurately predict dose response relationships. To address this need, we have developed a Geant4-based Monte Carlo patient-specific 3D dosimetry platform for TRT. This platform calculates patient-specific dose distributions based on serial CT/PET or CT/SPECT images acquired after injection of the TRT agent. In this work, S-values and specific absorbed fractions (SAFs) were calculated using this platform and benchmarked against reference values. Methods: S-values for 1, 10, 100, and 1000g spherical tumors with uniform activity distributions of I-124, I-125, I-131, F-18, and Ra-223 were calculated and compared to OLINDA/EXM reference values. SAFs for monoenergetic photons of 0.01, 0.1, and 1 MeV and S factors for monoenergetic electrons of 0.935 MeV were calculated for the liver, kidneys, lungs, pancreas, spleen, and adrenals in the Zubal Phantom and compared with previously published values. Sufficient particles were simulated to keep the voxel statistical uncertainty below 5%. Results: The calculated spherical S-values agreed within a few percent of reference data from OLINDA/EXM for each radionuclide and sphere size. The comparison of photon SAFs and electron S-values with previously published values showed good agreement with the previously published values. The S-values and SAFs of the source organs agreed within 1%. Conclusion: Our platform has been benchmarked against reference values for a variety of radionuclides and over a wide range of energies and tumor sizes. Therefore, this platform could be used to provide accurate patientspecific dosimetry for use in radiopharmaceutical clinical trials

  19. Intercomparison of absorbed dose to water and air-kerma based dosimetry protocols for photon and electron beams

    International Nuclear Information System (INIS)

    Huq, M.S.

    2002-01-01

    Full text: During the last three decades the International Atomic Energy Agency (IAEA), the American Association of Physicists in Medicine (AAPM) and organizations from various countries have published Codes of Practice (CoP) and dosimetry protocols for the calibration of high-energy photon and electron beams. They are based on the air-kerma or exposure calibration factor of an ionization chamber in a 60 Co gamma ray beam and formalism for the determination of absorbed dose to water in reference conditions. In recent years, the IAEA (IAEA TRS-398) and the AAPM (AAPM TG-51) have published new external beam dosimetry protocols that are based on the use of an ionization chamber calibrated in terms of absorbed dose to water in a standards laboratory's reference quality beam. These two new protocols follow those by the German Standard DIN, the British IPSM and the IAEA CoP for plane-parallel chambers, which have discussed and implemented the procedures for the determination of absorbed dose-to-water based on standards of absorbed dose-to-water. Since the publication of these protocols and CoPs, many comparisons, theoretical as well as experimental, between them have been published in the literature providing valuable information about the sources of similarities and discrepancies that exist among them. For example, the differences in the basic data for photon and electron beams included in the various IAEA CoPs are very small for the second edition of TRS-277 for photons, TRS-381 for electrons and TRS-398. In these cases the data changes posed by the adoption of TRS-398 are within about ±0.3% for the most commonly used energies. When implementing TRS-398 in these cases, the main difference will arise from the transition from K air to D w standards. For example, experimental comparison of absorbed doses between TRS-398 and TRS-277 for photons show an average difference of about 0.3% for most commonly used energies with a maximum difference of about 1% at a TPR 20

  20. Oak Ridge National Laboratory Embrittlement Data Base (EDB) and Dosimetry Evaluation (DE) program

    International Nuclear Information System (INIS)

    Pace, J.V. III; Remec, I.; Wang, J.A.; White, J.E.

    1996-01-01

    The objective of this program is to develop, maintain, and upgrade computerized data bases, calculational procedures, and standards relating to reactor pressure vessel fluence spectra determinations and embrittlement assessments. As part of this program, the information from radiation embrittlement research on nuclear reactor pressure vessel steels and from power reactor surveillance reports is maintained in a data base published on a periodic basis. The Embrittlement Data Base (EDB) effort consists of verifying the quality of the EDB, providing user-friendly software to access and process the data, and exploring and assessing embrittlement prediction models. The Dosimetry Evaluation effort consists of maintaining and upgrading validated neutron and gamma radiation transport procedures, maintaining cross-section libraries with the latest evaluated nuclear data, and maintaining and updating validated dosimetry procedures and data bases. The information available from this program provides data for assisting the Office of Nuclear Reactor Regulation, with support from the Office of Nuclear Regulatory Research, to effectively monitor current procedures and data bases used by vendors, utilities, and service laboratories in the pressure vessel irradiation surveillance program

  1. On the feasibility of comprehensive high-resolution 3D remote dosimetry

    International Nuclear Information System (INIS)

    Juang, Titania; Grant, Ryan; Adamovics, John; Ibbott, Geoffrey; Oldham, Mark

    2014-01-01

    Purpose: This study investigates the feasibility of remote high-resolution 3D dosimetry with the PRESAGE®/Optical-CT system. In remote dosimetry, dosimeters are shipped out from a central base institution to a remote institution for irradiation, then shipped back to the base institution for subsequent readout and analysis. Methods: Two nominally identical optical-CT scanners for 3D dosimetry were constructed and placed at the base (Duke University) and remote (Radiological Physics Center) institutions. Two formulations of PRESAGE® (SS1, SS2) radiochromic dosimeters were investigated. Higher sensitivity was expected in SS1, which had higher initiator content (0.25% bromotrichloromethane), while greater temporal stability was expected in SS2. Four unirradiated PRESAGE® dosimeters (two per formulation, cylindrical dimensions 11 cm diameter, 8.5–9.5 cm length) were imaged at the base institution, then shipped to the remote institution for planning and irradiation. Each dosimeter was irradiated with the same simple treatment plan: an isocentric 3-field “cross” arrangement of 4 × 4 cm open 6 MV beams configured as parallel opposed laterals with an anterior beam. This simple plan was amenable to accurate and repeatable setup, as well as accurate dose modeling by a commissioned treatment planning system (Pinnacle). After irradiation and subsequent (within 1 h) optical-CT readout at the remote institution, the dosimeters were shipped back to the base institution for remote dosimetry readout 3 days postirradiation. Measured on-site and remote relative 3D dose distributions were registered to the Pinnacle dose calculation, which served as the reference distribution for 3D gamma calculations with passing criteria of 5%/2 mm, 3%/3 mm, and 3%/2 mm with a 10% dose threshold. Gamma passing rates, dose profiles, and color-maps were all used to assess and compare the performance of both PRESAGE® formulations for remote dosimetry. Results: The best agreements between the

  2. MO-D-BRD-02: In Memoriam of Bengt Bjarngard: SBRT II: Small Field Dosimetry - TG155

    International Nuclear Information System (INIS)

    Das, I; Reft, C

    2014-01-01

    Specialized radiation treatment such as SRS/SRT. SBRT, IMRT, VMAT, Tomotherapy, CyberKnife and Gamma Knife use small fields or combination of small fields where dosimetry is challenging and uncertain due to non-equilibrium conditions such as longitudinal and lateral disequilibrium. Additionally the primary photon fluence is greatly affected by the obstruction of the source size by the jaws creating a large dose gradient across the field. Electronic equilibrium is a phenomenon associated with the range of secondary particles which depend on the beam energy, photon spectrum and the composition of the medium. Additionally, the finite size of detectors creates volume averaging and fluence perturbations especially in small fields. The IAEA/AAPM has provided a frame work for non-compliant reference dosimetry in small fields1. The AAPM TG-1552 has adopted this frame work to provide guidelines in relative dosimetry. This course provides the insight of TG-155 that defines small field, provides recommendations for suitable detectors and associated correction factors to convert reading to dose. Recommendations of a good working practice for relative dosimetry measurements (PDD, TMR, output factor, etc.) and dose calculations based on the new formulation is are elaborated. It also discusses beam modeling and dose calculations as a critical step in clinical utilization of small field radiotherapy. Small errors in beam data, approximations in dose algorithms, or misaligned of detectors and field settings can propagate into large errors in planned and delivered dose. The modeling and treatment planning aspects of small field dosimetry are reviewed with emphasis on the most critical parts for ensuring accurate and safe radiation therapy. Discussion on k(fmsr, fclin) for commercially available detectors are also provided.1 P. Alfonso, P. Andreo, R. Capote, M. S. Huq, W. Kilby, P. Kjall, T. R. Mackie, H. Palmans, K. Rosser, J. Seuntjens, W. Ullrich and S. Vatnitsky, “A new

  3. A dosimetry study comparing NCS report-5, IAEA TRS-381, AAPM TG-51 and IAEA TRS-398 in three clinical electron beam energies

    International Nuclear Information System (INIS)

    Palmans, Hugo; Nafaa, Laila; Patoul, Nathalie de; Denis, Jean-Marc; Tomsej, Milan; Vynckier, Stefaan

    2003-01-01

    New codes of practice for reference dosimetry in clinical high-energy photon and electron beams have been published recently, to replace the air kerma based codes of practice that have determined the dosimetry of these beams for the past twenty years. In the present work, we compared dosimetry based on the two most widespread absorbed dose based recommendations (AAPM TG-51 and IAEA TRS-398) with two air kerma based recommendations (NCS report-5 and IAEA TRS-381). Measurements were performed in three clinical electron beam energies using two NE2571-type cylindrical chambers, two Markus-type plane-parallel chambers and two NACP-02-type plane-parallel chambers. Dosimetry based on direct calibrations of all chambers in 60 Co was investigated, as well as dosimetry based on cross-calibrations of plane-parallel chambers against a cylindrical chamber in a high-energy electron beam. Furthermore, 60 Co perturbation factors for plane-parallel chambers were derived. It is shown that the use of 60 Co calibration factors could result in deviations of more than 2% for plane-parallel chambers between the old and new codes of practice, whereas the use of cross-calibration factors, which is the first recommendation in the new codes, reduces the differences to less than 0.8% for all situations investigated here. The results thus show that neither the chamber-to-chamber variations, nor the obtained absolute dose values are significantly altered by changing from air kerma based dosimetry to absorbed dose based dosimetry when using calibration factors obtained from the Laboratory for Standard Dosimetry, Ghent, Belgium. The values of the 60 Co perturbation factor for plane-parallel chambers (k att · k m for the air kerma based and p wall for the absorbed based codes of practice) that are obtained from comparing the results based on 60 Co calibrations and cross-calibrations are within the experimental uncertainties in agreement with the results from other investigators

  4. Neutron personnel dosimetry

    International Nuclear Information System (INIS)

    Griffith, R.V.

    1981-01-01

    The current state-of-the-art in neutron personnel dosimetry is reviewed. Topics covered include dosimetry needs and alternatives, current dosimetry approaches, personnel monitoring devices, calibration strategies, and future developments

  5. Which accelerator photon beams are 'clinic-like' for reference dosimetry purposes?

    International Nuclear Information System (INIS)

    Kalach, N.I.; Rogers, D.W.O.

    2003-01-01

    Previous work has demonstrated that, for photon beam dosimetry, TPR 10 20 is not an ideal beam quality specifier for all bremsstrahlung beams, especially for lightly filtered beams in some standards laboratories. This paper addresses the following questions: Is TPR 10 20 an adequate beam quality specifier for all modern clinical therapy accelerators? When can nonclinical beams in standards laboratories be used to calibrate ion chambers or measure k Q factors as a function of TPR 10 20 ? Based on detailed Monte Carlo simulations of Varian, Siemens, Elekta, and GE (Saturn) accelerators one can conclude that TPR 10 20 is an adequate beam quality specifier for all these machines in the sense that for a given value of TPR 10 20 , the value of stopping-power ratios is the same. Agreement between calculations for specific accelerators and measured beam quality specifiers is shown to be good, but agreement with published data for a variety of clinical accelerators is not as good. Possible reasons for the discrepancy are discussed

  6. Experimental verification of internal dosimetry calculations. Annual progress report

    International Nuclear Information System (INIS)

    1980-05-01

    During the past year a dosimetry research program has been established in the School of Nuclear Engineering at the Georgia Institute of Technology. The major objective of this program has been to provide research results upon which a useful internal dosimetry system could be based. The important application of this dosimetry system will be the experimental verification of internal dosimetry calculations such as those published by the MIRD Committee

  7. Characterization of commercial MOSFETS electron dosimetry

    International Nuclear Information System (INIS)

    Carvajal, M. A.; Simancas, F.; Guirado, D.; Banqueri, J.; Vilches, M.; Lallena, A. M.; Palma, A. J.

    2011-01-01

    In recent years there have been commercial dosimetry devices based on transistors Metal-Oxide-Semiconductor (MOSFET) having a number of advantages over traditional systems for dosimetry in medical applications. These include the portability of the sensor element and a reading process quick and relatively simple dose, linearity, and so on. The use of electron beams is important in modern radiotherapy include its use in intra-operative radiotherapy (RIO). This paper presents an initial characterization of different business models MOSFET, not specific for radiation detection, to demonstrate their potential as sensors for electron beam dosimetry. (Author)

  8. Dosimetry of ionizing radiation. Fundamentals and applications. Dosimetrie ionisierender Strahlen. Grundlagen und Anwendungen

    Energy Technology Data Exchange (ETDEWEB)

    Reich, H [ed.

    1990-01-01

    In the first chapter of the book, a brief description is given of the historical development of dosimetry, of its objectives and special role within the context of general physical metrology, followed by detailed explanations of the physical fundamentals of this science: the sources and fields of radiation, interactions between radiation and matter as well as radiation detectors. The terminology and units of measurement used in dosimetry are explained in a separate chapter. Chapters 7 and 8, which outline the various theoretical and experimental methods of dose determination, are the most essential contributions to this volume. Chapter 9 deals with the ways in which dosimetry is used in special cases in radiotherapy as well as in the measurement of very small or very large doses. Chapter 10 gives a survey of recently introduced units of measurements and methods to calculate the body dose with reference to the particular type of exposure used. Appendix A contains tables of measuring units, physical constants and measuring techniques along with at-a-glance information on the legal regulations concerning the calibration of dosimeters. Appendix B gives practical guidance on the handling of hardware-related inaccuracies of measurement in dose determination procedures and appendix C embraces 22 pages of tables showing data on radiation physics. (orig./HP) With 150 figs., 50 tabs. in the text, and annex with tables.

  9. Dosimetry in dentistry.

    Science.gov (United States)

    Asha, M L; Chatterjee, Ingita; Patil, Preeti; Naveen, S

    2015-01-01

    The purpose of this paper was to review various dosimeters used in dentistry and the cumulative results of various studies done with various dosimeters. Several relevant PubMed indexed articles from 1999 to 2013 were electronically searched by typing "dosimeters", "dosimeters in dentistry", "properties of dosimeters", "thermoluminescent and optically stimulated dosimeters", "recent advancements in dosimetry in dentistry." The searches were limited to articles in English to prepare a concise review on dental dosimetry. Titles and abstracts were screened, and articles that fulfilled the criteria of use of dosimeters in dental applications were selected for a full-text reading. Article was divided into four groups: (1) Biological effects of radiation, (2) properties of dosimeters, (3) types of dosimeters and (4) results of various studies using different dosimeters. The present review on dosimetry based on various studies done with dosimeters revealed that, with the advent of radiographic technique the effective dose delivered is low. Therefore, selection of radiological technique plays an important role in dental dose delivery.

  10. A multi-centre dosimetry audit on advanced radiotherapy in lung as part of the Isotoxic IMRT study

    Directory of Open Access Journals (Sweden)

    Yat Tsang

    2017-10-01

    Conclusion: This multi-centre dosimetry audit of complex IMRT/VMAT delivery provides confidence in the accuracy of modern planning and delivery systems in inhomogeneous tissues. The findings from this study can be used as a reference for future dosimetry audits.

  11. Survivor dosimetry. Part D. Graphical comparisons of measurements and calculations for neutrons and gamma rays

    International Nuclear Information System (INIS)

    Egbert, Stephen D.; Cullings, Harry M.

    2005-01-01

    An important part of validating the DS02 dosimetry system is the comparison of calculated initial neutron and gamma-ray radiation activation from the atomic bombs with all measurements that have been made, both before and during this current dosimetry reevaluation. All measurements that were made before the year 2002 are listed in Table 5 of Chapter 4. Many of these measurements have been compared to previous versions of the dosimetry systems for Hiroshima and Nagasaki. In this section the measurements are compared to the new dosimetry system DS02. For the purposes of showing historical context, they are also compared to the previous dosimetry system DS86. References for these measurements are found in Chapter 4. (J.P.N.)

  12. Evaluation of a LED-based flatbed document scanner for radiochromic film dosimetry in transmission mode.

    Science.gov (United States)

    Lárraga-Gutiérrez, José Manuel; García-Garduño, Olivia Amanda; Treviño-Palacios, Carlos; Herrera-González, José Alfredo

    2018-03-01

    Flatbed scanners are the most frequently used reading instrument for radiochromic film dosimetry because its low cost, high spatial resolution, among other advantages. These scanners use a fluorescent lamp and a CCD array as light source and detector, respectively. Recently, manufacturers of flatbed scanners replaced the fluorescent lamp by light emission diodes (LED) as a light source. The goal of this work is to evaluate the performance of a commercial flatbed scanner with LED based source light for radiochromic film dosimetry. Film read out consistency, response uniformity, film-scanner sensitivity, long term stability and total dose uncertainty was evaluated. In overall, the performance of the LED flatbed scanner is comparable to that of a cold cathode fluorescent lamp (CCFL). There are important spectral differences between LED and CCFL lamps that results in a higher sensitivity of the LED scanner in the green channel. Total dose uncertainty, film response reproducibility and long-term stability of LED scanner are slightly better than those of the CCFL. However, the LED based scanner has a strong non-uniform response, up to 9%, that must be adequately corrected for radiotherapy dosimetry QA. The differences in light emission spectra between LED and CCFL lamps and its potential impact on film-scanner sensitivity suggest that the design of a dedicated flat-bed scanner with LEDs may improve sensitivity and dose uncertainty in radiochromic film dosimetry. Copyright © 2018 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  13. Dosimetry in nuclear power plants

    International Nuclear Information System (INIS)

    Lastra B, J. A.

    2008-12-01

    To control the occupationally exposed personnel dose working at the Laguna Verde nuclear power plant, two types of dosemeters are used, the thermoluminescent (TLD) which is processed monthly, and the direct reading dosemeter that is electronic and works as daily control of personal dose. In the case of the electronic dosemeters of direct reading conventional, the readings and dose automatic registers and the user identity to which he was assigned to each dosemeter was to carry out the restricted area exit. In activities where the ionizing radiation sources are not fully characterized, it is necessary to relocate the personal dosemeter or assigned auxiliary dosemeters (TLDs and electronics) to determine the dose received by the user to both whole body and in any specific area of it. In jobs more complicated are used a tele dosimetry system where the radiation protection technician can be monitoring the user dose to remote control, the data transmission is by radio. The dosimetry activities are documented in procedures that include dosemeter inventories realization, the equipment and dosemeters calibration, the dosimetry quality control and the discrepancies investigation between the direct reading and TLD systems. TLD dosimetry to have technical expertise in direct and indirect dosimetry and two technicians in TLD dosimetry; electronic dosimetry to have 4 calibration technicians. For the electronic dosemeters are based on a calibrator source of Cesium-137. TLD dosemeters to have an automatic radiator, an automatic reader which can read up to 100 TLD dosemeters per hour and a semiautomatic reader. To keep the equipment under a quality process was development a process of initial entry into service and carried out a periodic verification of the heating cycles. It also has a maintenance contract for the equipment directly with the manufacturer to ensure their proper functioning. The vision in perspective of the dosimetry services of Laguna Verde nuclear power plant

  14. Selected references on thermoluminescent dosemeters for personnel monitoring

    International Nuclear Information System (INIS)

    Lawson, Helen

    1976-08-01

    This bibliography contains references on: specific thermoluminescent dosemeters used for personnel dosimetry; comparisons of thermoluminescent and other dosemeters for personnel monitoring and read-out apparatus for thermoluminescent dosemeters. An appendix contains selected foreign language references. (author)

  15. Retrospective dosimetry of Chernobyl liquidators

    International Nuclear Information System (INIS)

    Chumak, V.V.; Bakhanova, E.V.; Sholom, S.V.; Pasalskaya, L.F.; Bouville, A.; Krjuchkov, V.P.

    2000-01-01

    sets and, clearly, may lead to conclusion regarding the adequacy of the data set in general, not on individual basis. Another possibility to verify existing dose records is application of reliable retrospective dosimetric techniques, which may be used as a reference. Dosimetric screening of the study cohort requires a tool, which should meet two basic requirements: to be cheap and practical, and to be applicable to all subjects (desirably even post mortem). Till recent time such tool was missing and none of the known methods of retrospective dosimetry matched these criteria. Therefore in the novel method of Soft Expert Assessment Dosimetry (SEAD) was developed by the International Dosimetric Group operating under auspices of Ukraine-USA-France and CEC-Russia-Byelarus collaboration. This method is based on the analysis of information acquired from interviewing of liquidators and exploits regularities of dose distributions. The main advantage of this method is applicability to all subjects making it good for the screening of the cohort. Case-control study requires closer consideration of fewer subjects and in this regard high precision techniques (like EPR) make use. High cost of analyses is acceptable in this case. Practical implementation of this approach is illustrated by some on-going studies. Pros and contras of selected methods, as well as implementation considerations will be discussed as well. (author)

  16. Personal dosimetry service of VF, a.s. company

    International Nuclear Information System (INIS)

    Prasek, P.

    2009-01-01

    The VF, a.s. Company will extend its services in the area of personal dosimetry at the end of 2008, which is fully in compliance with the requirements of the Atomic Act, section 9 paragraph (1) letter r) and Decree on Radiation Protection, section 59 paragraph (1) letter a). Optically stimulated luminescence was selected in VF .a.s. as the most advantageous and the most advanced technology for the integral personal dosimetry. Optically stimulated luminescence (OSL) has been using in dosimetry for more than ten years. Although it is relatively new technology , its indisputable advantages predetermine that technology has significantly benefited in personal dosimetry services within a short time all over the advanced world. The VF, a.s. personal dosimetry service is based on the licensed products of LANDAUER, the US company, which is the world leader in OSL dosimetry. Crystalline Al 2 O 3 :C was selected as the detection material. All equipment of personal dosimetry service is installed in the VF Centre of Technology in Cerna Hora. The personal dosimetry service is incorporated in the International LANDAUER Dosimetry Service Network, and in the European Union, it is directly linked to the LANDAUER European Headquarters with its office in Paris. As a part of the OSL technology licence, the VF personal dosimetry service was included in the inter-laboratory comparison programme of the LANDAUER syndicate. (author)

  17. Personal dosimetry service of VF, a.s. company

    International Nuclear Information System (INIS)

    Prasek, P.

    2008-01-01

    The VF, a.s. Company will extend its services in the area of personal dosimetry at the end of 2008, which is fully in compliance with the requirements of the Atomic Act, section 9 paragraph (1) letter r) and Decree on Radiation Protection, section 59 paragraph (1) letter a). Optically stimulated luminescence was selected in VF .a.s. as the most advantageous and the most advanced technology for the integral personal dosimetry . Optically stimulated luminescence (OSL) has been using in dosimetry for more than ten years. Although it is relatively new technology , its indisputable advantages predetermine that technology has significantly benefited in personal dosimetry services within a short time all over the advanced world. The VF, a.s. personal dosimetry service is based on the licensed products of LANDAUER, the US company, which is the world leader in OSL dosimetry. Crystalline Al 2 O 3 :C was selected as the detection material. All equipment of personal dosimetry service is installed in the VF Centre of Technology in Cerna Hora. The personal dosimetry service is incorporated in the International LANDAUER Dosimetry Service Network, and in the European Union, it is directly linked to the LANDAUER European Headquarters with its office in Paris. As a part of the OSL technology licence, the VF personal dosimetry service was included in the inter-laboratory comparison programme of the LANDAUER syndicate. (author)

  18. High dose per fraction dosimetry of small fields with Gafchromic EBT2 film

    International Nuclear Information System (INIS)

    Hardcastle, Nicholas; Basavatia, Amar; Bayliss, Adam; Tome, Wolfgang A.

    2011-01-01

    Purpose: Small field dosimetry is prone to uncertainties due to the lack of electronic equilibrium and the use of the correct detector size relative to the field size measured. It also exhibits higher sensitivity to setup errors as well as large variation in output with field size and shape. Radiochromic film is an attractive method for reference dosimetry in small fields due to its ability to provide 2D dose measurements while having minimal impact on the dose distribution. Gafchromic EBT2 has a dose range of up to 40 Gy; therefore, it could potentially be useful for high dose reference dosimetry with high spatial resolution. This is a requirement in stereotactic radiosurgery deliveries, which deliver high doses per fraction to small targets. Methods: Targets of 4 mm and 12 mm diameters were treated to a minimum peripheral dose of 21 Gy prescribed to 80% of the maximum dose in one fraction. Target doses were measured with EBT2 film (both targets) and an ion chamber (12 mm target only). Measured doses were compared with planned dose distributions using profiles through the target and minimum peripheral dose coverage. Results: The measured target doses and isodose coverage agreed with the planned dose within ±1 standard deviation of three measurements, which were 2.13% and 2.5% for the 4 mm and 12 mm targets, respectively. Conclusions: EBT2 film is a feasible dosimeter for high dose per fraction reference 2D dosimetry.

  19. A quantification of the effectiveness of EPID dosimetry and software-based plan verification systems in detecting incidents in radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Bojechko, Casey; Phillps, Mark; Kalet, Alan; Ford, Eric C., E-mail: eford@uw.edu [Department of Radiation Oncology, University of Washington, 1959 N. E. Pacific Street, Seattle, Washington 98195 (United States)

    2015-09-15

    Purpose: Complex treatments in radiation therapy require robust verification in order to prevent errors that can adversely affect the patient. For this purpose, the authors estimate the effectiveness of detecting errors with a “defense in depth” system composed of electronic portal imaging device (EPID) based dosimetry and a software-based system composed of rules-based and Bayesian network verifications. Methods: The authors analyzed incidents with a high potential severity score, scored as a 3 or 4 on a 4 point scale, recorded in an in-house voluntary incident reporting system, collected from February 2012 to August 2014. The incidents were categorized into different failure modes. The detectability, defined as the number of incidents that are detectable divided total number of incidents, was calculated for each failure mode. Results: In total, 343 incidents were used in this study. Of the incidents 67% were related to photon external beam therapy (EBRT). The majority of the EBRT incidents were related to patient positioning and only a small number of these could be detected by EPID dosimetry when performed prior to treatment (6%). A large fraction could be detected by in vivo dosimetry performed during the first fraction (74%). Rules-based and Bayesian network verifications were found to be complimentary to EPID dosimetry, able to detect errors related to patient prescriptions and documentation, and errors unrelated to photon EBRT. Combining all of the verification steps together, 91% of all EBRT incidents could be detected. Conclusions: This study shows that the defense in depth system is potentially able to detect a large majority of incidents. The most effective EPID-based dosimetry verification is in vivo measurements during the first fraction and is complemented by rules-based and Bayesian network plan checking.

  20. Neutron Reference Benchmark Field Specification: ACRR Free-Field Environment (ACRR-FF-CC-32-CL).

    Energy Technology Data Exchange (ETDEWEB)

    Vega, Richard Manuel [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Parma, Edward J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Griffin, Patrick J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Vehar, David W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-07-01

    This report was put together to support the International Atomic Energy Agency (IAEA) REAL- 2016 activity to validate the dosimetry community’s ability to use a consistent set of activation data and to derive consistent spectral characterizations. The report captures details of integral measurements taken in the Annular Core Research Reactor (ACRR) central cavity free-field reference neutron benchmark field. The field is described and an “a priori” calculated neutron spectrum is reported, based on MCNP6 calculations, and a subject matter expert (SME) based covariance matrix is given for this “a priori” spectrum. The results of 31 integral dosimetry measurements in the neutron field are reported.

  1. PTTL Dose Re-estimation Applied to Quality Control in TLD-100 Based Personal Dosimetry

    International Nuclear Information System (INIS)

    Muniz, J.L.; Correcher, V.; Delgado, A.

    1999-01-01

    A new method for quality control of dose performance in Personal Dosimetry using TLD-100 is presented. This method consists of the application of dose reassessment techniques based on phototransferred thermoluminescence (PTTL). Reassessment is achieved through a second TL readout of the dosemeters worn by the controlled workers, after a reproducible UV exposure. Recent refinements in the PTTL technique developed in our laboratory allow reassessing doses as low as 0.2 mSv, thus extending the reassessment capability to the entire dose range that must be monitored in personal dosimetry. After a one month exposure, even purely environmental doses can be reassessed. This method can be applied for either re-estimation of single doses or of the total dose accumulated after a number of exposures and dose measurements. Several tests to reconfirm low doses in normal working conditions for personal dosimetry have been performed. Each test consisted of several cycles of exposure and TL evaluations and a final PTTL re-estimation of the total accumulated dose in those cycles. The results obtained always showed very good agreement between the sum of the partial doses and the total reassessed dose. The simplicity of the method and the possibility of re-evaluating the doses assessed to the workers employing their own dosemeters are advantageous features to be considered in designing systems for the determination of real performance in personal dosimetry. (author)

  2. Polymer gel dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Baldock, C [Institute of Medical Physics, School of Physics, University of Sydney (Australia); De Deene, Y [Radiotherapy and Nuclear Medicine, Ghent University Hospital (Belgium); Doran, S [CRUK Clinical Magnetic Resonance Research Group, Institute of Cancer Research, Surrey (United Kingdom); Ibbott, G [Radiation Physics, UT M D Anderson Cancer Center, Houston, TX (United States); Jirasek, A [Department of Physics and Astronomy, University of Victoria, Victoria, BC (Canada); Lepage, M [Centre d' imagerie moleculaire de Sherbrooke, Departement de medecine nucleaire et de radiobiologie, Universite de Sherbrooke, Sherbrooke, QC (Canada); McAuley, K B [Department of Chemical Engineering, Queen' s University, Kingston, ON (Canada); Oldham, M [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Schreiner, L J [Cancer Centre of South Eastern Ontario, Kingston, ON (Canada)], E-mail: c.baldock@physics.usyd.edu.au, E-mail: yves.dedeene@ugent.be

    2010-03-07

    Polymer gel dosimeters are fabricated from radiation sensitive chemicals which, upon irradiation, polymerize as a function of the absorbed radiation dose. These gel dosimeters, with the capacity to uniquely record the radiation dose distribution in three-dimensions (3D), have specific advantages when compared to one-dimensional dosimeters, such as ion chambers, and two-dimensional dosimeters, such as film. These advantages are particularly significant in dosimetry situations where steep dose gradients exist such as in intensity-modulated radiation therapy (IMRT) and stereotactic radiosurgery. Polymer gel dosimeters also have specific advantages for brachytherapy dosimetry. Potential dosimetry applications include those for low-energy x-rays, high-linear energy transfer (LET) and proton therapy, radionuclide and boron capture neutron therapy dosimetries. These 3D dosimeters are radiologically soft-tissue equivalent with properties that may be modified depending on the application. The 3D radiation dose distribution in polymer gel dosimeters may be imaged using magnetic resonance imaging (MRI), optical-computerized tomography (optical-CT), x-ray CT or ultrasound. The fundamental science underpinning polymer gel dosimetry is reviewed along with the various evaluation techniques. Clinical dosimetry applications of polymer gel dosimetry are also presented. (topical review)

  3. Internal Dosimetry. Chapter 18

    Energy Technology Data Exchange (ETDEWEB)

    Hindorf, C. [Department of Radiation Physics, Skåne University Hospital, Lund (Sweden)

    2014-12-15

    The Committee on Medical Internal Radiation Dose (MIRD) is a committee within the Society of Nuclear Medicine. The MIRD Committee was formed in 1965 with the mission to standardize internal dosimetry calculations, improve the published emission data for radionuclides and enhance the data on pharmacokinetics for radiopharmaceuticals [18.1]. A unified approach to internal dosimetry was published by the MIRD Committee in 1968, MIRD Pamphlet No. 1 [18.2], which was updated several times thereafter. Currently, the most well known version is the MIRD Primer from 1991 [18.3]. The latest publication on the formalism was published in 2009 in MIRD Pamphlet No. 21 [18.4], which provides a notation meant to bridge the differences in the formalism used by the MIRD Committee and the International Commission on Radiological Protection (ICRP) [18.5]. The formalism presented in MIRD Pamphlet No. 21 [18.4] will be used here, although some references to the quantities and parameters used in the MIRD primer [18.3] will be made. All symbols, quantities and units are presented.

  4. Dosimetry in radiotherapy. V.1

    International Nuclear Information System (INIS)

    1988-01-01

    A series of symposia on dosimetry in medicine and biology have been held by the IAEA in co-operation with WHO. The present symposium was the first one focusing on ''Dosimetry in Radiotherapy''. The papers presented reflected the different steps in the calibration chain such as the calibration standards established by the National Standards Laboratories and the conversion of the reading of calibrated instruments to the desired quantity, i.e. absorbed dose to water at a reference point in the user's beam at the radiotherapy clinic. The programme further examined the procedures necessary for optimization of the treatment of the patient, such as treatment planning methods, dose distribution studies, new techniques of dose measurement, improvements in the physical dose distributions/conformation therapy and special problems involved in total body treatments. Results of quality assurance in radiotherapy were presented from local hospitals as well as from national and international studies. Refs, figs and tabs

  5. Environmental dosimetry system based on LiF : Mg, Ti (TLD-100)

    International Nuclear Information System (INIS)

    Saez Vergara, J.C.

    1990-01-01

    The report presents the various tests carried out to the characterize a thermoluminescence environmental dosimetry systems, using the phosphor LiF:mg,Ti (TLD-100) in chip form. The holder has been specifically designed in order to obtain simplicity in the operation and to assure correct measurements in terms of the new operational quantities in radiation protection (ICRU-1985). Some topics in TLD Environmental Monitoring are discussed (Dark Current, Reference Light, Zero Reading, Free-in-Air or Phantom Calibration, Fading Correction, Transit Dose, etc.), and the proposed solutions are exposed. The tests performed have been designed to conform with the different existing international Standards and Recommendations (ANSI : N545-1975; IEC: Draft 45B-1987, ISO : DP 8034-19849. The data from an European Interlaboratory Programm (EUR-8932) have been used to evaluate the performance : the TLD System presented is among the best systems using TLD-100. The results obtained in the characterization (linearity, repeatability, detection threshold, residue, angular response, stability of stored information, etc.) show the optimum performance of this dosimetric system in its application to environmental gamma dose monitoring. Based on these results, two operational procedures have been developed for the application of this Dosimetric System, specially in Quality Assurance Monitoring Programs around Nuclear Plants in Spain. (author)

  6. Total skin high-dose-rate electron therapy dosimetry using TG-51

    International Nuclear Information System (INIS)

    Gossman, Michael S.; Sharma, Subhash C.

    2004-01-01

    An approach to dosimetry for total skin electron therapy (TSET) is discussed using the currently accepted TG-51 high-energy calibration protocol. The methodology incorporates water phantom data for absolute calibration and plastic phantom data for efficient reference dosimetry. The scheme is simplified to include the high-dose-rate mode conversion and provides support for its use, as it becomes more available on newer linear accelerators. Using a 6-field, modified Stanford technique, one may follow the process for accurate determination of absorbed dose

  7. Current trends on internal dosimetry for patient protection in nuclear medicine

    International Nuclear Information System (INIS)

    Rojo, A.M.; Gisone, P.A.; Kunst, J.J.

    2001-01-01

    The associated risk-benefit analyses in nuclear medicine implicitly performed by the clinician have been straightforward. Relatively low administered activity activities yield important diagnostic information, the benefit of which far outweigh any potential risk associated with the attendant normal tissue radiation doses. Such small risk to benefit ratios have been very forgiving of possible inaccuracies in dose estimates. With the ongoing development of new radiopharmaceutical and the increasing therapeutic application of internal radionuclides, radiation dosimetry in nuclear medicine continues to evolve from population- and organ-average to patient-specific dose estimation. Patient-specific dosimetry refers to the estimation of radiation dose to tissues of a specific-patients based on their individual body and measured biokinetics rather than an average anthropomorphic model and hypothetic kinetic. The importance of dosimetry specific-patient considers to avoid the risk of an unsuitable treatment and/or with probability of damage to the patient. This is illustrated by the dosimetric approaches to radioiodine treatment of hyperthyroidism. The most common prescription algorithm to fix the activity administered to a hyperthyroid patient does not consider individual parameters that are highly variable (thyroid uptake, biological half-life, thyroid mass). Its arbitrary approach doesn't permit individually optimized therapy and it may be inappropriate and even hazardous. (author)

  8. Dosimetry quality audit of high energy photon beams in greek radiotherapy centers

    International Nuclear Information System (INIS)

    Hourdakis, Constantine J.; Boziari, A.

    2008-01-01

    Background and purpose: Dosimetry quality audits and intercomparisons in radiotherapy centers is a useful tool in order to enhance the confidence for an accurate therapy and to explore and dissolve discrepancies in dose delivery. This is the first national comprehensive study that has been carried out in Greece. During 2002 - 2006 the Greek Atomic Energy Commission performed a dosimetry quality audit of high energy external photon beams in all (23) Greek radiotherapy centers, where 31 linacs and 13 Co-60 teletherapy units were assessed in terms of their mechanical performance characteristics and relative and absolute dosimetry. Materials and Methods: The quality audit in dosimetry of external photon beams took place by means of on-site visits, where certain parameters of the photon beams were measured, calculated and assessed according to a specific protocol and the IAEA TRS 398 dosimetry code of practice. In each radiotherapy unit (Linac or Co-60), certain functional parameters were measured and the results were compared to tolerance values and limits. Doses in water under reference and non reference conditions were measured and compared to the stated values. Also, the treatment planning systems (TPS) were evaluated with respect to irradiation time calculations. Results: The results of the mechanical tests, dosimetry measurements and TPS evaluation have been presented in this work and discussed in detail. This study showed that Co-60 units had worse performance mechanical characteristics than linacs. 28% of all irradiation units (23% of linacs and 42% of Co-60 units) exceeded the acceptance limit at least in one mechanical parameter. Dosimetry accuracy was much worse in Co60 units than in linacs. 61% of the Co60 units exhibited deviations outside ±3% and 31% outside ±5%. The relevant percentages for the linacs were 24% and 7% respectively. The results were grouped for each hospital and the sources of errors (functional and human) have been investigated and

  9. Dosimetry quality audit of high energy photon beams in greek radiotherapy centers.

    Science.gov (United States)

    Hourdakis, Constantine J; Boziari, A

    2008-04-01

    Dosimetry quality audits and intercomparisons in radiotherapy centers is a useful tool in order to enhance the confidence for an accurate therapy and to explore and dissolve discrepancies in dose delivery. This is the first national comprehensive study that has been carried out in Greece. During 2002--2006 the Greek Atomic Energy Commission performed a dosimetry quality audit of high energy external photon beams in all (23) Greek radiotherapy centers, where 31 linacs and 13 Co-60 teletherapy units were assessed in terms of their mechanical performance characteristics and relative and absolute dosimetry. The quality audit in dosimetry of external photon beams took place by means of on-site visits, where certain parameters of the photon beams were measured, calculated and assessed according to a specific protocol and the IAEA TRS 398 dosimetry code of practice. In each radiotherapy unit (Linac or Co-60), certain functional parameters were measured and the results were compared to tolerance values and limits. Doses in water under reference and non reference conditions were measured and compared to the stated values. Also, the treatment planning systems (TPS) were evaluated with respect to irradiation time calculations. The results of the mechanical tests, dosimetry measurements and TPS evaluation have been presented in this work and discussed in detail. This study showed that Co-60 units had worse performance mechanical characteristics than linacs. 28% of all irradiation units (23% of linacs and 42% of Co-60 units) exceeded the acceptance limit at least in one mechanical parameter. Dosimetry accuracy was much worse in Co60 units than in linacs. 61% of the Co60 units exhibited deviations outside +/-3% and 31% outside +/-5%. The relevant percentages for the linacs were 24% and 7% respectively. The results were grouped for each hospital and the sources of errors (functional and human) have been investigated and discussed in details. This quality audit proved to be a

  10. Cross sections required for FMIT dosimetry

    International Nuclear Information System (INIS)

    Gold, R.; McElroy, W.N.; Lippincott, E.P.; Mann, F.M.; Oberg, D.L.; Roberts, J.H.; Ruddy, F.H.

    1980-01-01

    The Fusion Materials Irradiation Test (FMIT) facility, currently under construction, is designed to produce a high flux of high energy neutrons for irradiation effects experiments on fusion reactor materials. Characterization of the flux-fluence-spectrum in this rapidly varying neutron field requires adaptation and extension of currently available dosimetry techniques. This characterization will be carried out by a combination of active, passive, and calculational dosimetry. The goal is to provide the experimenter with accurate neutron flux-fluence-spectra at all positions in the test cell. Plans have been completed for a number of experimental dosimetry stations and provision for these facilities has been incorporated into the FMIT design. Overall needs of the FMIT irradiation damage program delineate goal accuracies for dosimetry that, in turn, create new requirements for high energy neutron cross section data. Recommendations based on these needs have been derived for required cross section data and accuracies

  11. Evaluation of the efficiency of different methods of personal dosimetry in vascular interventional radiology

    International Nuclear Information System (INIS)

    Bacchim Neto, F.A.; Alves, A.F.F.; Rosa, M.E.D.; Pina, D.R.

    2017-01-01

    Interventional Radiology - IR is the area of medicine that provides the largest occupational exposures. The dose values to which interventionists are exposed are difficult to standardize. The objective of the study is to perform a complete evaluation of occupational exposures and to determine the efficiency of different personal dosimetry methods used in IR. We evaluated the efficiencies of 6 different personal dosimetry methodologies used internationally to estimate the effective dose received by interventional professionals. And, based on this analysis, determine the characteristics of each methodology. One of the methods of personal dosimetry recommended by Brazilian legislation was the most conservative, overestimating, on average, the effective dose of professionals by up to 200%, reaching maximum values close to 400%. The most accurate method was that used in North America. This method did not overestimate the effective dose of the professionals more than a few percent and their standard deviation relative to the effective reference dose were the lowest. Based on these results, the choice of methodologies employing at least two dosimeters, one under and above protective aprons is recommended. In addition, in some situations where the dose in the hands may be high, additional dosimeters for this region are also recommended

  12. Boron dose determination for BNCT using Fricke and EPR dosimetry

    International Nuclear Information System (INIS)

    Wielopolski, L.; Ciesielski, B.

    1995-01-01

    In Boron Neutron Capture Therapy (BNCT) the dominant dose delivered to the tumor is due to α and 7 Li charged particles resulting from a neutron capture by 10 B and is referred to herein as the boron dose. Boron dose is directly attributable to the following two independent factors, one boron concentration and the neutron capture energy dependent cross section of boron, and two the energy spectrum of the neutrons that interact with boron. The neutron energy distribution at a given point is dictated by the incident neutron energy distribution, the depth in tissue, geometrical factors such as beam size and patient's dimensions. To account for these factors can be accommodated by using Monte Carlo theoretical simulations. However, in conventional experimental BNCT dosimetry, e.g., using TLDs or ionization chambers, it is only possible to estimate the boron dose. To overcome some of the limitations in the conventional dosimetry, modifications in ferrous sulfate dosimetry (Fricke) and Electron Paramagnetic Resonance (EPR) dosimetry in alanine, enable to measure specifically boron dose in a mixed gamma neutron radiation fields. The boron dose, in either of the dosimeters, is obtained as a difference between measurements with boronated and unboronated dosimeters. Since boron participates directly in the measurements, the boron dosimetry reflects the true contribution, integral of the neutron energy spectrum with boron cross section, of the boron dose to the total dose. Both methods are well established and used extensively in dosimetry, they are presented briefly here

  13. Techniques for radiation measurements: Micro-dosimetry and dosimetry

    International Nuclear Information System (INIS)

    Waker, A. J.

    2006-01-01

    Experimental Micro-dosimetry is concerned with the determination of radiation quality and how this can be specified in terms of the distribution of energy deposition arising from the interaction of a radiation field with a particular target site. This paper discusses various techniques that have been developed to measure radiation energy deposition over the three orders of magnitude of site-size; nano-meter, micrometer and millimetre, which radiation biology suggests is required to fully account for radiation quality. Inevitably, much of the discussion will concern the use of tissue-equivalent proportional counters and variants of this device, but other technologies that have been studied, or are under development, for their potential in experimental Micro-dosimetry are also covered. Through an examination of some of the quantities used in radiation metrology and dosimetry the natural link with Micro-dosimetric techniques will be shown and the particular benefits of using Micro-dosimetric methods for dosimetry illustrated. (authors)

  14. Individualised dosimetry in patients with differentiated thyroid cancer based on external dose-rate. Optimisation of the number of measurements.

    Science.gov (United States)

    Bautista-Ballesteros, J A; Torres-Espallardo, I; Borrelli, P; Rivas-Sanchez, A; Bello, P; Martí-Bonmatí, L

    2016-01-01

    To compare the results of individual dosimetry in differentiated thyroid cancer patients treated with (131)I at our centre with the established limits and dosimetry results of published studies. Analysis of the optimal number of measurements necessary to reduce the impact of dosimetry for the comfort of the patient and, secondly, on the workload of health workers. Dosimetry was performed in the Nuclear Medicine Department of the University and Polytechnic Hospital La Fe, on 29 patients suffering from differentiated thyroid cancer and treated with activities between 1.02 and 5.51 GBq (mean 2.68 GBq) of (131)I. The Spanish Society of Medical Physics (SEFM) protocol was used, based on measurements of external dose rate adjusted to a bi-exponential curve according to a two compartment model. Different dosimetries were performed on each patient, taking different selections of the available measurements in order to find the optimal number. Results are well below the dosimetry limits, and are consistent with those obtained in other centres. The number of measurements can be reduced from 5, as proposed in the SEFM protocol, to 4 without significant loss of accuracy. Further reducing measures may be justified in individual cases. The values obtained for the dosimetry quantities are significantly below the established limits. A reduction in measurements can be assumed at the cost of a moderate increase in uncertainty, benefiting the patient. Copyright © 2015 Elsevier España, S.L.U. and SEMNIM. All rights reserved.

  15. Thermoluminescence albedo-neutron dosimetry

    International Nuclear Information System (INIS)

    Strand, T.; Storruste, A.

    1986-10-01

    The report discusses neutron detection with respect to dosimetry and compares different thermoluminescent dosimetry materials for neutron dosimetry. Construction and calibration of a thermoluminescence albedo neutron dosemeter, developed by the authors, is described

  16. Introduction to dosimetry and risk estimation of second cancer induction following radiotherapy

    International Nuclear Information System (INIS)

    Harrison, R.M.

    2013-01-01

    This brief review of dosimetry in second cancer dosimetry introduces work carried out by Working Group 9 (Radiation Protection Dosimetry in Medicine) of the European Radiation Dosimetry Group (EURADOS). The work described in the following papers in this edition was presented at a Workshop on Dosimetry for Second Cancer Risk Estimation given at the EURADOS Annual meeting in Vienna on February 8th 2012. The work concentrates on the measurement of out-of-field doses in water tanks and BOMAB-like phantoms using a variety of dosimeters to measure photon and neutron doses. These include optically stimulated luminescence (OSL), radiophotoluminescence (RPL) and thermoluminescence (TLD) dosimeters for photon dosimetry (together with ion chambers for reference measurements traceable to primary standards) and track etch and bubble detectors for neutron measurements. A discussion of the various phantoms available for these measurements is presented together with a brief introduction to a model for the relationship between organ doses and the risk of induction of second cancers. The estimation of second cancer risks is not trivial and involves processes which are currently incompletely understood. However, progress in this field requires a robust foundation and methodology for the measurement or calculation of organ doses following radiotherapy, so that risks can be placed in perspective, algorithms for out-of-field doses can be compared with measured data, and future epidemiological studies may have a reliable foundation of organ dosimetry for retrospective dosimetry studies. -- Highlights: ► Brief review of second cancer induction following radiotherapy. ► Out-of-field doses for estimating risks to remote organs. ► Introduction to dosimetry techniques and dosimeters used. ► Out-of-field dose measurements in phantoms

  17. Retrospective dosimetry (or self dosimetry): Application to French Nuclear Power Plants

    International Nuclear Information System (INIS)

    Lloret, R.

    1993-01-01

    In this text we give the dosimetry principle on irradiated materials such baffle screw, pressure vessel and control element cans. This measure, made by gammametry, is based on the steel activation and comparison with calculated measures by Actige code. 4 figs., 6 refs

  18. Applications of gel dosimetry

    International Nuclear Information System (INIS)

    Ibbott, Geoffrey S

    2004-01-01

    Gel dosimetry has been examined as a clinical dosimeter since the 1950s. During the last two decades, however, a rapid increase in the number of investigators has been seen, and the body of knowledge regarding gel dosimetry has expanded considerably. Gel dosimetry is still considered a research project, and the introduction of this tool into clinical use is proceeding slowly. This paper will review the characteristics of gel dosimetry that make it desirable for clinical use, the postulated and demonstrated applications of gel dosimetry, and some complications, set-backs, and failures that have contributed to the slow introduction into routine clinical use

  19. Radiation dosimetry activities in the Netherlands

    International Nuclear Information System (INIS)

    Broerse, J.J.; Mijnheer, B.J.

    1986-07-01

    The Netherlands Commission for Radiation Dosimetry (NCS) was officially established on 3 September 1982 with the aim of promoting the appropriate use of dosimetry of ionizing radiation both for scientific research and practical applications. The present report provides a compilation of the dosimetry acitivities and expertise available in the Netherlands, based on the replies to a questionnaire mailed under the auspices of the NCS and might suffer from some incompleteness in specific details. The addresses of the Dutch groups with the names of the scientists are given. Individual scientists, not connected with a scientific group, hospital or organization have not been included in this list. Also the names of commercial firms producing dosimetric systems have been omitted. (Auth.)

  20. Interactive and automated systems for nuclear track measurements with applications to fast neutron dosimetry

    International Nuclear Information System (INIS)

    Roberts, J.H.; Gold, R.; McNeece, J.P.; Preston, C.C.; Ruddy, F.H.

    1983-12-01

    Interactive and automatic track measuring systems have been developed primarily for fast neutron dosimetry in and around reactors. The interactive system is used for proton recoil measurements in nuclear research emulsions and the automatic systems for counting fission fragment tracks in Muscovite mica. The status of these systems, along with illustrative applications, are presented, particularly with regard to their relationship to neutron personnel dosimetry. 16 references, 12 figures

  1. Computer dosimetry of 192Ir wire

    International Nuclear Information System (INIS)

    Kline, R.W.; Gillin, M.T.; Grimm, D.F.; Niroomand-Rad, A.

    1985-01-01

    The dosimetry of 192 Ir linear sources with a commercial treatment planning computer system has been evaluated. Reference dose rate data were selected from the literature and normalized in a manner consistent with our clinical and dosimetric terminology. The results of the computer calculations are compared to the reference data and good agreement is shown at distances within about 7 cm from a linear source. The methodology of translating source calibration in terms of exposure rate for use in the treatment planning computer is developed. This may be useful as a practical guideline for users of similar computer calculation programs for iridium as well as other sources

  2. Introduction of a new dosimetry system based on optically stimulated luminescence (OSL) in our personal monitoring service

    International Nuclear Information System (INIS)

    Hubner, S.

    2014-08-01

    The personal monitoring service named Auswertungsstelle is part of the Helmholtz Zentrum Munchen, a non-profit-making research center in Germany. As one of the four monitoring services in Germany, we have been a reliable partner in radiation protection for more than 60 years. With about 1.9 million dose assessments per year, we are the largest monitoring service in Europe. For dozens of years, our main dosimeter used in whole-body dosimetry has been a film dosimeter. Although its dosimetric properties are still up to date, film dosimetry won.t be a sustainable technique for the use in monitoring services. Therefore, a project with the objective of investigating alternative dosimetric materials and methods was launched in the late 1990 at the Helmholtz Zentrum Munchen. Based on this research work, the use of Be O as an OSL dosimeter was studied by the radiation physics group of the Tu Dresden, by order and on account of the Auswertungsstelle at the Helmholtz Zentrum Munchen. It was shown, that ceramic Be O features promising dosimetric properties, making Be O detectors particularly suitable for being used in all applications in whole-body dosimetry measuring photons. Ceramic Be O material has an excellent resistance to environmental influences. The Be O chips are almost tissue equivalent. Therefore, these detectors show low photon energy dependence. A new personal dosimetry system based on the OSL dosimetry of Be O was developed. Applying this system, the Auswertungsstelle offers OSL-dosimeters for official monitoring of the Personal Dose Equivalent Hp(10) since 2011. This OSL-System is accredited according to DIN IEC 62387 and we obtained the corresponding type approval by the Ptb, the national metrology institute in Germany. Sophisticated logistics was developed and installed. High degree of automation was achieved by robots for dosimeter assembly and machines for packing, labelling and unpacking of the dosimeters. To become a sustainable dosimetry system not only

  3. Introduction of a new dosimetry system based on optically stimulated luminescence (OSL) in our personal monitoring service

    Energy Technology Data Exchange (ETDEWEB)

    Hubner, S., E-mail: stephan.huebner@helmholtz-muenchen.de [Helmholtz Zentrum Munchen, German Research Center for Environmental Health, D-80219, Munich (Georgia)

    2014-08-15

    The personal monitoring service named Auswertungsstelle is part of the Helmholtz Zentrum Munchen, a non-profit-making research center in Germany. As one of the four monitoring services in Germany, we have been a reliable partner in radiation protection for more than 60 years. With about 1.9 million dose assessments per year, we are the largest monitoring service in Europe. For dozens of years, our main dosimeter used in whole-body dosimetry has been a film dosimeter. Although its dosimetric properties are still up to date, film dosimetry won.t be a sustainable technique for the use in monitoring services. Therefore, a project with the objective of investigating alternative dosimetric materials and methods was launched in the late 1990 at the Helmholtz Zentrum Munchen. Based on this research work, the use of Be O as an OSL dosimeter was studied by the radiation physics group of the Tu Dresden, by order and on account of the Auswertungsstelle at the Helmholtz Zentrum Munchen. It was shown, that ceramic Be O features promising dosimetric properties, making Be O detectors particularly suitable for being used in all applications in whole-body dosimetry measuring photons. Ceramic Be O material has an excellent resistance to environmental influences. The Be O chips are almost tissue equivalent. Therefore, these detectors show low photon energy dependence. A new personal dosimetry system based on the OSL dosimetry of Be O was developed. Applying this system, the Auswertungsstelle offers OSL-dosimeters for official monitoring of the Personal Dose Equivalent Hp(10) since 2011. This OSL-System is accredited according to DIN IEC 62387 and we obtained the corresponding type approval by the Ptb, the national metrology institute in Germany. Sophisticated logistics was developed and installed. High degree of automation was achieved by robots for dosimeter assembly and machines for packing, labelling and unpacking of the dosimeters. To become a sustainable dosimetry system not only

  4. Activity Of EURADOS In Environmental Solid State Dosimetry

    International Nuclear Information System (INIS)

    Ranogajec-Komor, M.; Duch, M. A.; Haninger, T.

    2015-01-01

    H*(10) area dosimeters used for ERM (IC2014env) took place from spring to autumn 2014 at (PTB). Dosimeters were exposed at different PTB reference measuring sites to check the home calibration as well as the response of the dosimetry systems to cosmic and terrestrial radiation. 33 dosimetry systems were investigated in total by exposing 16 dosimeters per system under different conditions. Special attention was taken for the transport dose correction. Preliminary results demonstrated that the dosimeter response values were mostly around 1 in a band of ± 20 %, but a pronounced over-response to cosmic radiation has been observed. (author).

  5. Patient dosimetry in diagnostic radiology

    International Nuclear Information System (INIS)

    Shrimpton, P.C.

    2000-01-01

    Full text: X-ray examinations remain an essential and widely used diagnostic tool in medicine and hence the most significant source of exposure to man-made radiation for populations. Patterns of practice in diagnostic radiology continue to evolve, with overall growth in the numbers of procedures worldwide and, particularly in developed countries, increasing importance for complex procedures such as computed tomography (CT) and interventional techniques. In order to maximise the benefits from x-rays relative to the associated radiation risks, there is a need to ensure the prior justification of all examinations and the optimisation of patient protection such that doses are as low as reasonably practicable to meet specific clinical requirements. Accordingly, patient dosimetry is a fundamental requirement in diagnostic radiology. Detailed measurements for the assessment of risks or comparison of different types of procedure require the estimation of organ and effective doses. Such comprehensive dosimetry necessarily involves the simulation of clinical practice using anthropomorphic phantoms, with either measurements in a physical phantom or calculations utilising a mathematical phantom. Simpler measurements for the routine monitoring of dose in x-ray departments can be based on practical quantities such as entrance surface dose, dose-area product and, for CT, weighted CT dose index and dose-length product. Widescale surveys reveal significant variations between departments in the typical doses for a given type of procedure and potential scope for dose reductions. In order to promote improvements in practice, the results of periodic dose surveys in departments should be compared with appropriate standards, such as diagnostic reference levels for adult and paediatric patients, that are set nationally or locally for the purposes of promoting critical review of the equipment and techniques in use. Patient dosimetry should form an essential element of routine quality

  6. Use of aspartame-based sweetener tablets in emergency dosimetry using EPR.

    Science.gov (United States)

    Maghraby, A; Salama, E

    2010-06-01

    Accident dosimetry aims to evaluate the unplanned radiation doses delivered to individuals through one of the objects exist in the area of the accident. The gamma dose response of free radicals generated in irradiated aspartame tablets and its usability for emergency dosimetry was studied. EPR spectra of unirradiated and irradiated aspartame-based sweetener were recorded. Two signals arise after irradiating, S(1) at g (S(1)) = 2.00229 +/- 0.00097 and S(2) at g (S(2)) = 2.00262 +/- 0.00088. Some EPR parameters were studied for radiation-induced radicals in aspartame sweeteners tablets, such as the microwave saturation behaviour, the effect of magnetic field modulation amplitude on the peak-to-peak height and peak-to-peak line width for both of S(1) and S(2). Responses of S(1) and S(2) to different radiation doses were studied and resulted in linear relationships, radicals persistence curves were plotted over a 49-d storage period. It was found that Aspartame sweeteners tablets are useful in the range from 0.96 to 39.96 Gy. Radiation-induced radicals possess reasonable stability.

  7. MO-B-BRB-04: 3D Dosimetry in End-To-End Dosimetry QA

    Energy Technology Data Exchange (ETDEWEB)

    Ibbott, G. [UT MD Anderson Cancer Center (United States)

    2016-06-15

    Full three-dimensional (3D) dosimetry using volumetric chemical dosimeters probed by 3D imaging systems has long been a promising technique for the radiation therapy clinic, since it provides a unique methodology for dose measurements in the volume irradiated using complex conformal delivery techniques such as IMRT and VMAT. To date true 3D dosimetry is still not widely practiced in the community; it has been confined to centres of specialized expertise especially for quality assurance or commissioning roles where other dosimetry techniques are difficult to implement. The potential for improved clinical applicability has been advanced considerably in the last decade by the development of improved 3D dosimeters (e.g., radiochromic plastics, radiochromic gel dosimeters and normoxic polymer gel systems) and by improved readout protocols using optical computed tomography or magnetic resonance imaging. In this session, established users of some current 3D chemical dosimeters will briefly review the current status of 3D dosimetry, describe several dosimeters and their appropriate imaging for dose readout, present workflow procedures required for good dosimetry, and analyze some limitations for applications in select settings. We will review the application of 3D dosimetry to various clinical situations describing how 3D approaches can complement other dose delivery validation approaches already available in the clinic. The applications presented will be selected to inform attendees of the unique features provided by full 3D techniques. Learning Objectives: L. John Schreiner: Background and Motivation Understand recent developments enabling clinically practical 3D dosimetry, Appreciate 3D dosimetry workflow and dosimetry procedures, and Observe select examples from the clinic. Sofie Ceberg: Application to dynamic radiotherapy Observe full dosimetry under dynamic radiotherapy during respiratory motion, and Understand how the measurement of high resolution dose data in an

  8. SSDL newsletter. No. 25[Secondary Standard Dosimetry Laboratories

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1986-10-01

    In April 1976 the IAEA and the WHO concluded a Working Arrangement concerning the establishment and operation of a network of Secondary Standard Dosimetry Laboratories, based on a relationship agreement between the two organizations of 1959. This Working Arrangement was the outcome of rather lengthy consultations on the subject which rooted in recommendations of an experts' meeting on SSDL Activities, held in Rio de Janeiro 1974, and which put the bulk of responsibility for running the network on WHO. In particular, it was agreed then that WHO would provide the secretariat for the Network and be responsible for the SSDL Advisory Group of experts, the terms of reference of which were laid down in a separate document. After about ten years of operation of the SSDL Network it was felt that revision of the Working Arrangement should be considered, taking care of the actual involvement of the two organizations in the project and providing a more fairly balanced share of responsibilities between the IAEA and WHO secretaries of the Network. The new Arrangement was drafted during 1985 and signed by the two Directors General in October/November 1985. Upon recommendation of an SSDL Advisory Group which met in November 1984 the Directors General of IAEA and WHO appointed 6 scientists as members of a standing SSDL Scientific Committee. The appointment is for a period of three years. In its terms of reference the functions of this Committee are defined as follows: to provide technical advice to the Directors General of the IAEA and WHO regarding the programme of work of the IAEA/WHO Network of Secondary Standard Dosimetry Laboratories; to assist the Network Secretariat with scientific advice and to regularly review the work undertaken by members of the SSDL Network; to make recommendations on the techniques for carrying out intercomparisons between SSDLs; to advise and make recommendations on the techniques for establishing and maintaining traceability to the Primary Standard

  9. A comprehensive tool for image-based generation of fetus and pregnant women mesh models for numerical dosimetry studies

    International Nuclear Information System (INIS)

    Dahdouh, S; Serrurier, A; De la Plata, J-P; Anquez, J; Angelini, E D; Bloch, I; Varsier, N; Wiart, J

    2014-01-01

    Fetal dosimetry studies require the development of accurate numerical 3D models of the pregnant woman and the fetus. This paper proposes a 3D articulated fetal growth model covering the main phases of pregnancy and a pregnant woman model combining the utero-fetal structures and a deformable non-pregnant woman body envelope. The structures of interest were automatically or semi-automatically (depending on the stage of pregnancy) segmented from a database of images and surface meshes were generated. By interpolating linearly between fetal structures, each one can be generated at any age and in any position. A method is also described to insert the utero-fetal structures in the maternal body. A validation of the fetal models is proposed, comparing a set of biometric measurements to medical reference charts. The usability of the pregnant woman model in dosimetry studies is also investigated, with respect to the influence of the abdominal fat layer. (paper)

  10. Radon dosimetry for workers: ICRP's approach

    International Nuclear Information System (INIS)

    Marsh, James W.; Laurier, Dominique; Tirmarche, Margot

    2017-01-01

    The International Commission on Radiological Protection (ICRP) has recently published two reports on radon exposure; Publication 115 on lung cancer risks from radon and radon progeny and Publication 126 on radiological protection against radon exposure. A specific graded approach for the control of radon in workplaces is recommended where a dose assessment is required in certain situations. In its forthcoming publication on Occupational Intakes of Radionuclides (OIR) document, Part 3, effective dose coefficients for radon and thoron will be provided. These will be calculated using ICRP reference biokinetic and dosimetric models. Sufficient information and dosimetric data will be given so that site-specific dose coefficients can be calculated based on measured aerosol parameter values. However, ICRP will recommend a single dose coefficient of 12 mSv per working level month (WLM) for inhaled radon progeny to be used in most circumstances. This chosen reference value was based on both dosimetry and epidemiological data. In this paper, the application and use of dose coefficients for workplaces are discussed including the reasons for the choice of the reference value. Preliminary results of dose calculations for indoor workplaces and mines are presented. The paper also briefly describes the general approach for the management of radon exposure in workplaces based both on ICRP recommendations and the European directive (2013/59/EURATOM). (authors)

  11. The RERF dosimetry measurements database

    International Nuclear Information System (INIS)

    Cullings, Harry M.; Fujita, Shoichiro; Preston, Dale L.; Grant, Eric J.; Shizuma, Kiyoshi; Hoshi, Masaharu; Maruyama, Takashi; Lowder, Wayne M.

    2005-01-01

    The Radiation Effects Research Foundation maintains a database containing detailed information on every known measurement of environmental materials in the cities of Hiroshima and Nagasaki for gamma-ray thermoluminescence or neutron activation produced by incident radiation from the atomic bomb detonations. The intent was to create a single information resource that would consistently document, as completely as possible in each case, a standard array of data for every known measurement. This database provides a uniquely comprehensive and carefully designed reference for the dosimetry reassessment. (J.P.N.)

  12. Dosimetry Service

    CERN Multimedia

    2005-01-01

    Please remember to read your dosimeter at least once a month. Regular read-outs are vital to ensure that your personal dose is periodically monitored. Dosimeters should be read even if you have not visited the controlled areas. Dosimetry Service - Tel. 72155 http://cern.ch/rp-dosimetry

  13. Neutron personnel dosimetry considerations for fusion reactors

    International Nuclear Information System (INIS)

    Barton, T.P.; Easterly, C.E.

    1979-07-01

    The increasing development of fusion reactor technology warrants an evaluation of personnel neutron dosimetry systems to aid in the concurrent development of a radiation protection program. For this reason, current state of knowledge neutron dosimeters have been reviewed with emphasis placed on practical utilization and the problems inherent in each type of dosimetry system. Evaluations of salient parameters such as energy response, latent image instability, and minimum detectable dose equivalent are presented for nuclear emulsion films, track etch techniques, albedo and other thermoluminescent dosimetry techniques, electrical conductivity damage effects, lyoluminescence, thermocurrent, and thermally stimulated exoelectron emission. Brief summaries of dosimetry regulatory requirements and intercomparison study results help to establish compliance and recent trends, respectively. Spectrum modeling data generated by the Neutron Physics Division of Oak Ridge National Laboratory for the Princeton Tokamak Fusion Test Reactor (TFTR) Facility have been analyzed by both International Commission on Radiological Protection fluence to dose conversion factors and an adjoint technique of radiation dosimetry, in an attempt to determine the applicability of current neutron dosimetry systems to deuterium and tritium fusion reactor leakage spectra. Based on the modeling data, a wide range of neutron energies will probably be present in the leakage spectra of the TFTR facility, and no appreciable risk of somatic injury to occupationally exposed workers is expected. The relative dose contributions due to high energy and thermal neutrons indicate that neutron dosimetry will probably not be a serious limitation in the development of fusion power

  14. Methods and Models of the Hanford Internal Dosimetry Program, PNNL-MA-860

    Energy Technology Data Exchange (ETDEWEB)

    Carbaugh, Eugene H.; Bihl, Donald E.; Maclellan, Jay A.; Antonio, Cheryl L.; Hill, Robin L.

    2009-09-30

    The Hanford Internal Dosimetry Program (HIDP) provides internal dosimetry support services for operations at the Hanford Site. The HIDP is staffed and managed by the Radiation and Health Technology group, within the Pacific Northwest National Laboratory (PNNL). Operations supported by the HIDP include research and development, the decontamination and decommissioning of facilities formerly used to produce and purify plutonium, and waste management activities. Radioelements of particular interest are plutonium, uranium, americium, tritium, and the fission and activation product radionuclides 137Cs, 90Sr, and 60Co. This manual describes the technical basis for the design of the routine bioassay monitoring program and for assessment of internal dose. The purposes of the manual are as follows: • Provide assurance that the HIDP derives from a sound technical base. • Promote the consistency and continuity of routine program activities. • Provide a historical record. • Serve as a technical reference for radiation protection personnel. • Aid in identifying and planning for future needs.

  15. Thermoluminescence in medical dosimetry

    International Nuclear Information System (INIS)

    Rivera, T.

    2011-10-01

    The dosimetry by thermoluminescence (Tl) is applied in the entire world for the dosimetry of ionizing radiations specially to personal and medical dosimetry. This dosimetry method has been very interesting for measures in vivo because the Tl dosimeters have the advantage of being very sensitive in a very small volume and they are also equivalent to tissue and they do not need additional accessories (for example, cable, electrometer, etc.) The main characteristics of the diverse Tl materials to be used in the radiation measures and practical applications are: the Tl curve, the share homogeneity, the signal stability after the irradiation, precision and exactitude, the response in function with the dose and the energy influence. In this work a brief summary of the advances of the radiations dosimetry is presented by means of the thermally stimulated luminescence and its application to the dosimetry in radiotherapy. (Author)

  16. Dose intercomparison studies for standardization of high-dose dosimetry in Viet Nam

    International Nuclear Information System (INIS)

    Mai Hoang Hoa; Duong Nguyen Dinh; Kojima, T.

    1999-01-01

    The Irradiation Center of the Vietnam Atomic Energy Commission (IC-VAEC) is planning to establish a traceability system for high-dose dosimetry and to provide high-dose standards as a secondary standard dosimetry laboratory (SSDL) level in Vietnam. For countries which do not have a standard dosimetry laboratory, the participation in the International Dose Assurance Service (IDAS) operated by the International Atomic Energy Agency (IAEA) is the most common means to verify own dosimetry performance with a certain uncertainty. This is, however, only one-direction dose intercomparison with evaluation by IAEA including unknown parameter at participant laboratories. The SSDL level laboratory should have traceability as well as compatibility, ability to evaluate uncertainties of its own dosimetry performance by itself In the present paper, we reviewed our dosimetry performance through two-way dose intercomparison studies and self-evaluation of uncertainty in our dosimetry procedure. The performance of silver dichromate dosimeter as reference transfer dosimeter in IC-VAEC was studied through two-way blind dose intercomparison experiments between the IC-VAEC and JAERI. As another channel of dose intercomparison with IAEA, alanine dosimeters issued by IDAS were simultaneously irradiated with the IC-VAEC dichromate dosimeters at IC-VAEC and analyzed by IAEA. Dose intercomparison between IC-VAEC and JAERI results into a good agreement (better than ±2.5%), and IDAS results also show similar agreement within ±3.0%. The uncertainty was self-estimated on the basis of the JAERI alanine dosimetry, and a preliminary value of about 1.86% at a 68% confidence level is established. The results from these intercomparisons and our estimation of the uncertainty are consistent. We hope that our experience is valuable to other countries which do not have dosimetry standard laboratories and/or are planning to establish them. (author)

  17. Neptunium: a bibliographic reference

    International Nuclear Information System (INIS)

    Mosley, R.E.

    1979-06-01

    A comprehensive bibliograhy of the literature on the element neptunium published prior to January 1976 is presented. A short abstract is given for each listed reference, with a few exceptions. The references are divided into sections categorized as General, Man-Made Sources (Reactors), Man-Made Sources (Fuel Reprocessing), Chemistry (Solubility), Chemistry (Compounds), Chemistry (Isotopes), Analyses (Instrumental), Analyses (Chemical), Chemical (Animal), Biological (Effects), Biological (Animal-Metabolism-Retention), Biological (Air Movement), Biological (Human Inhalation), Measurement, and Dosimetry. The bibliography contains author and keyword indexes and was compiled to serve as a quick reference source for neptunium-related work. 184 citations

  18. Neutron dosimetry - A review

    Energy Technology Data Exchange (ETDEWEB)

    Baum, J W

    1955-03-29

    This review summarizes information on the following subjects: (1) physical processes of importance in neutron dosimetry; (2) biological effects of neutrons; (3) neutron sources; and (4) instruments and methods used in neutron dosimetry. Also, possible improvements in dosimetry instrumentation are outlined and discussed. (author)

  19. Dosimetry Service

    CERN Multimedia

    2005-01-01

    Please remember to read your dosimeter at least once a month. Regular read-outs are vital to ensure that your personal dose is periodically monitored. Dosimeters should be read even if you have not visited the controlled areas. Dosimetry Service - Tel. 7 2155 http://cern.ch/rp-dosimetry

  20. Dosimetry Service

    CERN Multimedia

    Dosimetry Service

    2005-01-01

    Please remember to read your dosimeter at least once a month. Regular read-outs are vital to ensure that your personal dose is periodically monitored. Dosimeters should be read even if you have not visited the controlled areas. Dosimetry Service Tel. 7 2155 http://cern.ch/rp-dosimetry

  1. Dosimetry on the radiological risks prevention in radiotherapy

    International Nuclear Information System (INIS)

    Fornet R, O. M.; Perez G, F.

    2014-08-01

    Dosimetry in its various forms plays a determining role on the radiological risks prevention in radiotherapy. To prove this in this paper is shown an analysis based on the risk matrix method, how the dosimetry can influence in each stages of a radiotherapy service; installation and acceptance, operation, maintenance and calibration. For each one of these stages the role that can play is analyzed as either the initiating event of a radiological accident or limiting barrier of these events of the dosimetric processes used for the individual dosimetry, the area monitoring, fixed or portable, for radiation beam dosimetry and of the patients for a radiotherapy service with cobalt-therapy equipment. The result of the study shows that the application of a prospective approach in the role evaluation of dosimetry in the prevention and mitigation of the consequences of a radiological accident in radiotherapy is crucial and should be subject to permanent evaluation at each development stage of these services. (author)

  2. The role of the IAEA codes of practice in the radiation dosimetry dissemination chain

    International Nuclear Information System (INIS)

    Andreo, P.

    2002-01-01

    those of the national protocols. The goal was to develop an international CoP with the best of each national protocol, avoiding known imperfections and limitations. TRS-277 was addressed to both medical physicists and SSDLs worldwide, establishing homogeneity at all levels of the dosimetry chain, and it was adopted by several industrialized countries, ending with the thought that IAEA recommendations were addressed solely to developing countries. Interesting enough, in some other countries TRS-277 was seen as a competitor of the national protocol (even if this was among the 'parents' of the new CoP) rather than as an update, which was often referred to as a 'cosmetic change'. Due of its wide dissemination, TRS-277 became the 'standard protocol' against which the others were compared. Its data were included in practically all the dosimetry recommendations published since 1986, following an 'explosion' of national protocols, and many investigations have used 'modified' national dosimetry protocols that incorporate TRS-277 data. The CoP has been translated into many different languages, even if the only non-English version formally released by the Agency has been in Spanish. Like any other protocol, TRS-277 had also imperfections. Some of the correction factors had been included without a proper verification, and they turned out to be in error. Among these were certain perturbation correction factors in kV x-rays and high-energy photon and electron beams. A second edition of TRS-277 was published in 1997 correcting for these deficiencies. A major limitation (and criticism) had been the lack of detailed procedures for dosimetry based on the use of planeparallel chambers, and the CoP was complemented the same year with TRS-381 for that purpose. Being released in a period of dynamic changes, when new standards were being developed, TRS-381 served as the bridge between N K - and N D,w -based CoPs. The most recent international Code of Practice for radiotherapy dosimetry, TRS

  3. External audit in radiotherapy dosimetry

    International Nuclear Information System (INIS)

    Thwaites, D.I.; Western General Hospital, Edinburgh

    1996-01-01

    Quality audit forms an essential part of any comprehensive quality assurance programme. This is true in radiotherapy generally and in specific areas such as radiotherapy dosimetry. Quality audit can independently test the effectiveness of the quality system and in so doing can identify problem areas and minimize their possible consequences. Some general points concerning quality audit applied to radiotherapy are followed by specific discussion of its practical role in radiotherapy dosimetry, following its evolution from dosimetric intercomparison exercises to routine measurement-based on-going audit in the various developing audit networks both in the UK and internationally. Specific examples of methods and results are given from some of these, including the Scottish+ audit group. Quality audit in radiotherapy dosimetry is now well proven and participation by individual centres is strongly recommended. Similar audit approaches are to be encouraged in other areas of the radiotherapy process. (author)

  4. SU-E-T-05: A 2D EPID Transit Dosimetry Model Based On An Empirical Quadratic Formalism

    International Nuclear Information System (INIS)

    Tan, Y; Metwaly, M; Glegg, M; Baggarley, S; Elliott, A

    2014-01-01

    Purpose: To describe a 2D electronic portal imaging device (EPID) transit dosimetry model, based on an empirical quadratic formalism, that can predict either EPID or in-phantom dose distribution for comparisons with EPID captured image or treatment planning system (TPS) dose respectively. Methods: A quadratic equation can be used to relate the reduction in intensity of an exit beam to the equivalent path length of the attenuator. The calibration involved deriving coefficients from a set of dose planes measured for homogeneous phantoms with known thicknesses under reference conditions. In this study, calibration dose planes were measured with EPID and ionisation chamber (IC) in water for the same reference beam (6MV, 100mu, 20×20cm 2 ) and set of thicknesses (0–30cm). Since the same calibration conditions were used, the EPID and IC measurements can be related through the quadratic equation. Consequently, EPID transit dose can be predicted from TPS exported dose planes and in-phantom dose can be predicted using EPID distribution captured during treatment as an input. The model was tested with 4 open fields, 6 wedge fields, and 7 IMRT fields on homogeneous and heterogeneous phantoms. Comparisons were done using 2D absolute gamma (3%/3mm) and results were validated against measurements with a commercial 2D array device. Results: The gamma pass rates for comparisons between EPID measured and predicted ranged from 93.6% to 100.0% for all fields and phantoms tested. Results from this study agreed with 2D array measurements to within 3.1%. Meanwhile, comparisons in-phantom between TPS computed and predicted ranged from 91.6% to 100.0%. Validation with 2D array device was not possible for inphantom comparisons. Conclusion: A 2D EPID transit dosimetry model for treatment verification was described and proven to be accurate. The model has the advantage of being generic and allows comparisons at the EPID plane as well as multiple planes in-phantom

  5. Establishing working standards of chromosome aberrations analysis for biological dosimetry

    International Nuclear Information System (INIS)

    Bui Thi Kim Luyen; Tran Que; Pham Ngoc Duy; Nguyen Thi Kim Anh; Ha Thi Ngoc Lien

    2015-01-01

    Biological dosimetry is an dose assessment method using specify bio markers of radiation. IAEA (International Atomic Energy Agency) and ISO (International Organization for Standardization) defined that dicentric chromosome is specify for radiation, it is a gold standard for biodosimetry. Along with the documents published by IAEA, WHO, ISO and OECD, our results of study on the chromosome aberrations induced by radiation were organized systematically in nine standards that dealing with chromosome aberration test and micronucleus test in human peripheral blood lymphocytes in vitro. This standard addresses: the reference dose-effect for dose estimation, the minimum detection levels, cell culture, slide preparation, scoring procedure for chromosome aberrations use for biodosimetry, the criteria for converting aberration frequency into absorbed dose, reporting of results. Following these standards, the automatic analysis devices were calibrated for improving biological dosimetry method. This standard will be used to acquire and maintain accreditation of the Biological Dosimetry laboratory in Nuclear Research Institute. (author)

  6. Proceedings of the recent developments in radiation dosimetry

    International Nuclear Information System (INIS)

    Bhat, Nagesh; Palani Selvan, T.

    2016-01-01

    Whilst 'Dosimetry' in its original sense deals with methods for a quantitative determination of energy deposited in a given medium by directly or indirectly ionizing radiations, the term is better known as a scientific sub-specialty in the fields of health physics and medical physics, where it is the calculation and assessment of the radiation dose received by the human body. Dosimetry is used extensively for radiation protection and is routinely applied to ensure radiological safety of occupational radiation workers. Internal dosimetry due to the ingestion or inhalation of radioactive materials relies on a variety of physiological or imaging techniques. External dosimetry, due to irradiation from an external source is based on measurements with a dosimeter, or inferred from other radiological protection instruments. Radiation dosimetry is one of the important research areas of Department of Atomic Energy (DAE). This research work is centered on the facilities such as nuclear reactors, reprocessing plants, high energy accelerators (research/industry/medical), radiation standards, food processing, radiation technology development, etc. In each of these facilities, radiation field environment is different and the associated dosimetry concepts are different. Papers relevant to INIS are indexed separately

  7. Reconstructive dosimetry for cutaneous radiation syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Lima, C.M.A.; Lima, A.R.; Degenhardt, Ä.L.; Da Silva, F.C.A., E-mail: dasilva@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Valverde, N.J. [Fundacao Eletronuclear de Assistencia Medica, Rio de Janeiro, RJ (Brazil)

    2015-10-15

    According to the International Atomic Energy Agency (IAEA), a relatively significant number of radiological accidents have occurred in recent years mainly because of the practices referred to as potentially high-risk activities, such as radiotherapy, large irradiators and industrial radiography, especially in gammagraphy assays. In some instances, severe injuries have occurred in exposed persons due to high radiation doses. In industrial radiography, 80 cases involving a total of 120 radiation workers, 110 members of the public including 12 deaths have been recorded up to 2014. Radiological accidents in industrial practices in Brazil have mainly resulted in development of cutaneous radiation syndrome (CRS) in hands and fingers. Brazilian data include 5 serious cases related to industrial gammagraphy, affecting 7 radiation workers and 19 members of the public; however, none of them were fatal. Some methods of reconstructive dosimetry have been used to estimate the radiation dose to assist in prescribing medical treatment. The type and development of cutaneous manifestations in the exposed areas of a person is the first achievable gross dose estimation. This review article presents the state-of-the-art reconstructive dosimetry methods enabling estimation of local radiation doses and provides guidelines for medical handling of the exposed individuals. The review also presents the Chilean and Brazilian radiological accident cases to highlight the importance of reconstructive dosimetry. (author)

  8. Working conditions analysis according T.L. personal dosimetry results

    International Nuclear Information System (INIS)

    Marinkovic, O.; Jovanovic, S.

    2006-01-01

    Laboratory for personal dosimetry in the Institute of Occupational and Radiological Health, Belgrade, used TLD more than twenty years. Before that, film dosimetry was main method in external monitoring. T.L. dosimetry was started with Reader Toledo 654 and crystals Mg B 4 O 7 . Finally, from 1992 laboratory has Harshaw TLD Reader Model 6600. Dosimeters are crystals LiF type 100, card packed, worn in standard filtrated holders. Personal dosimetry data are keeping 30 years for each worker according to regulations. The data from 1990 are in electronic form. Long experience enables conclusion that new technique means more advantages in practice. Recommendation from this laboratory practice refers to TLD read-out cycle. The longest period should be one month. LiF is recommended crystal. Glow curve deconvolution gives information about chronological irradiation. It is very important to conclude was dosimetry irradiated by 'one-shot' or continuously. Preparing calibration for determination the time since accident laboratory has to define adequate dose calibration methodology including low temperature peaks. Possibility to follow working conditions analyzing TLD glow curve is much more important than low decrease of dose severity. Time depend analyze is not possible if TLD would be read-out more than (approximately) six weeks after irradiation. If ionizing sources produce such low dose and has negligible probability of accidental exposure (according nowadays regulation read-out frequency could be once in three month), the recommendation is not to use external personal monitoring. Reading personal dosimeters once in three months deemed not useful. Complete and successful personal dosimetry dictates using system that enables glow curve shape representation to be sure that signal is ionizing irradiation result or not. Time depend analyze imparts information about protection permanence. In special circumstance, it is possible to estimate the time of exposure. This is extremely

  9. SU-F-J-100: Standardized Biodistribution Template for Nuclear Medicine Dosimetry Collection and Reporting

    Energy Technology Data Exchange (ETDEWEB)

    Kesner, A [University of Colorado, Anschutz Medical Campus, Aurora, Colorado (United States); Poli, G [International Atomic Energy Agency, Vienna, Vienna (Austria); Beykan, S; Lassman, M [University of Wuerzburg, Wuerzberg, Wuerzberg (Germany)

    2016-06-15

    Purpose: As the field of Nuclear Medicine moves forward with efforts to integrate radiation dosimetry into clinical practice we can identify the challenge posed by the lack of standardized dose calculation methods and protocols. All personalized internal dosimetry is derived by projecting biodistribution measurements into dosimetry calculations. In an effort to standardize organization of data and its reporting, we have developed, as a sequel to the EANM recommendation of “Good Dosimetry Reporting”, a freely available biodistribution template, which can be used to create a common point of reference for dosimetry data. It can be disseminated, interpreted, and used for method development widely across the field. Methods: A generalized biodistribution template was built in a comma delineated format (.csv) to be completed by users performing biodistribution measurements. The template is available for free download. The download site includes instructions and other usage details on the template. Results: This is a new resource developed for the community. It is our hope that users will consider integrating it into their dosimetry operations. Having biodistribution data available and easily accessible for all patients processed is a strategy for organizing large amounts of information. It may enable users to create their own databases that can be analyzed for multiple aspects of dosimetry operations. Furthermore, it enables population data to easily be reprocessed using different dosimetry methodologies. With respect to dosimetry-related research and publications, the biodistribution template can be included as supplementary material, and will allow others in the community to better compare calculations and results achieved. Conclusion: As dosimetry in nuclear medicine become more routinely applied in clinical applications, we, as a field, need to develop the infrastructure for handling large amounts of data. Our organ level biodistribution template can be used as a

  10. Developments in physical dosimetry and radiation protection; Entwicklungen in der physikalischen Dosimetrie im Strahlenschutz

    Energy Technology Data Exchange (ETDEWEB)

    Fiebich, Martin [Technische Hochschule Mittelhessen, Giessen (Germany). Inst. fuer Medizinische Physik und Strahlenschutz

    2017-07-01

    In the frame of physical dosimetry new dose units have been defined: the depth personal dose (equivalent dose in 10 mm depth) and the surface personal dose (equivalent dose in 0.07 mm depth). Physical dosimetry is applied for the determination of occupational radiation exposure, the radiation protected area control, the estimation of radiation exposure of patients during radiotherapy, for quality assurance and in research projects and optimization challenges. Developments have appeared with respect to punctual measuring chambers, eye lens dosimetry, OSL (optically stimulated luminescence) dosimetry, real-time dosimetry and Monte Carlo methods. New detection limits of about 1 micro Gy were reached.

  11. Dosimetry for electron beam application

    International Nuclear Information System (INIS)

    Miller, A.

    1983-12-01

    This report describes two aspects of electron beam dosimetry, on one hand development of film dosimeters and measurements of their properties, and on the other hand development of calorimeters for calibration of routine dosimeters, e.g. thin films. Two types of radiochromic thin film dosimeters have been developed in this department, and the properties of these and commercially available dosimeters have been measured and found to be comparable. Calorimeters which are in use for routine measurements, are being investigated with reference to their application as standardizing instruments, and new calorimeters are being developed. (author)

  12. Personnel neutron dosimetry

    International Nuclear Information System (INIS)

    Hankins, D.

    1982-04-01

    This edited transcript of a presentation on personnel neutron discusses the accuracy of present dosimetry practices, requirements, calibration, dosemeter types, quality factors, operational problems, and dosimetry for a criticality accident. 32 figs

  13. Neutron dosimetry: problems, solutions, prospects and the role of trace detectors

    International Nuclear Information System (INIS)

    Fernandez, F.

    2009-10-01

    It is present in schematic way, the origin of the neutrons; their interaction with matter, until its application in the field of dosimetry. It describes some measuring instruments based on thermoluminescence dosimetry, some activation detectors and trace detectors. Finally, it summarizes the work in neutron dosimetry have been carried out at the Autonomous University of Barcelona. (Author)

  14. Personnel photographic film dosimetry

    International Nuclear Information System (INIS)

    Keirim-Markus, I.B.

    1981-01-01

    Technology of personnel photographic film dosimetry (PPD) based on the photographic effect of ionizing radiation is described briefly. Kinds of roentgen films used in PPD method are enumerated, compositions of a developer and fixing agents for these films are given [ru

  15. Variations of influence quantities in industrial irradiators and their effect on dosimetry performance

    International Nuclear Information System (INIS)

    Chu, R.D.H.

    1999-01-01

    Many environmental factors, including irradiation temperature, post-irradiation storage temperature, dose rate, relative humidity, oxygen content and the energy spectrum may affect the response of dosimetry systems used in industrial radiation processing. Although the effects of individual influence quantities have been extensively studied, the variations of these influence quantities in production irradiators and the complex relationships between the effects of different influence quantities make it difficult to assess the overall effect on the measurement uncertainty. In the development of new dosimetry systems it is important to know the effect of each influence quantity and developers of new dosimetry systems should perform studies over a wide range of irradiation conditions. Analysis parameters and manufacturing specifications should be chosen to minimize the effect of influence quantities in the environments where the dosimeters will be used. Because of possible relationships between different influence quantities, care must be taken to ensure that the response function determined in the calibration of the dosimetry system is applicable for the conditions in which the dosimeters will be used. Reference standard dosimetry systems which have been thoroughly studied and have known relationships between dose response and influence quantities should be used to verify the calibration of routine dosimetry systems under the actual conditions of use. Better understanding of the variations in influence quantities in industrial irradiators may be obtained by modeling or direct measurements and may provide improvements in the calibration of routine dosimetry system and reduction of the overall measurement uncertainty. (author)

  16. An experimental system for thermoluminescent dosimetry

    International Nuclear Information System (INIS)

    Perry, K.E.G.; George, E.

    1965-08-01

    A thermoluminescent dosimeter (T.L.D.) reader has been developed for experimental investigations on the use of lithium fluoride for 'finger tip' dosimetry. The design of the reader is based on the maximum use of standard electronic units in the A.E.R.E. Type 2000 series but some new unit development has been necessary. The reader gives improved experimental facilities over present commercially-available designs. The technique for 'finger-tip' dosimetry is described and the initial experimental results are given. (author)

  17. Skin dosimetry - radiological protection aspects of skin dosimetry

    International Nuclear Information System (INIS)

    Dennis, J.A.

    1991-01-01

    Following a Workshop in Skin Dosimetry, a summary of the radiological protection aspects is given. Aspects discussed include routine skin monitoring and dose limits, the need for careful skin dosimetry in high accidental exposures, techniques for assessing skin dose at all relevant depths and the specification of dose quantities to be measured by personal dosemeters and the appropriate methods to be used in their calibration. (UK)

  18. Use of aspartame-based sweetener tablets in emergency dosimetry using EPR

    International Nuclear Information System (INIS)

    Maghraby, A.; Salama, E.

    2010-01-01

    Accident dosimetry aims to evaluate the unplanned radiation doses delivered to individuals through one of the objects exist in the area of the accident. The gamma dose response of free radicals generated in irradiated aspartame tablets and its usability for emergency dosimetry was studied. EPR spectra of unirradiated and irradiated aspartame-based sweetener were recorded. Two signals arise after irradiating, S 1 at g (S 1 ) = 2.00229 ± 0.00097 and S 2 at g (S 2 ) = 2.00262 ± 0.00088. Some EPR parameters were studied for radiation-induced radicals in aspartame sweeteners tablets, such as the microwave saturation behaviour, the effect of magnetic field modulation amplitude on the peak-to-peak height and peak-to-peak line width for both of S 1 and S 2 . Responses of S 1 and S 2 to different radiation doses were studied and resulted in linear relationships, radicals persistence curves were plotted over a 49-d storage period. It was found that Aspartame sweeteners tablets are useful in the range from 0.96 to 39.96 Gy. Radiation-induced radicals possess reasonable stability. (authors)

  19. Semiconductor dosimetry system for gamma and neutron radiation

    International Nuclear Information System (INIS)

    Savic, Z.; Pavlovic, Z.

    1995-01-01

    The semiconductor dosimetry system for gamma and neutron radiation based on pMOS transistor and PIN diode is described. It is intended for tactical or accidental personal dosimetry. The production steps are given. The temperature, dose and time (fading) response are reported. Hardware and software requirements which are needed for obtaining the desired measurement error are pointed. (author)

  20. ESR Dosimetry

    International Nuclear Information System (INIS)

    Baffa, Oswaldo; Rossi, Bruno; Graeff, Carlos; Kinoshita, Angela; Chen Abrego, Felipe; Santos, Adevailton Bernardo dos

    2004-01-01

    ESR dosimetry is widely used for several applications such as dose assessment in accidents, medical applications and sterilization of food and other materials. In this work the dosimetric properties of natural and synthetic Hydroxyapatite, Alanine, and 2-Methylalanine are presented. Recent results on the use of a K-Band (24 GHz) ESR spectrometer in dosimetry are also presented

  1. Dosimetry for ocular proton beam therapy at the Harvard Cyclotron Laboratory based on the ICRU Report 59

    International Nuclear Information System (INIS)

    Newhauser, W.D.; Burns, J.; Smith, A.R.

    2002-01-01

    The Massachusetts General Hospital, the Harvard Cyclotron Laboratory (HCL), and the Massachusetts Eye and Ear Infirmary have treated almost 3000 patients with ocular disease using high-energy external-beam proton radiation therapy since 1975. The absorbed dose standard for ocular proton therapy beams at HCL was based on a fluence measurement with a Faraday cup (FC). A majority of proton therapy centers worldwide, however, use an absorbed dose standard that is based on an ionization chamber (IC) technique. The ion chamber calibration is deduced from a measurement in a reference 60 Co photon field together with a calculated correction factor that takes into account differences in a chamber's response in 60 Co and proton fields. In this work, we implemented an ionization chamber-based absolute dosimetry system for the HCL ocular beamline based on the recommendations given in Report 59 by the International Commission on Radiation Units and Measurements. Comparative measurements revealed that the FC system yields an absorbed dose to water value that is 1.1% higher than was obtained with the IC system. That difference is small compared with the experimental uncertainties and is clinically insignificant. In June of 1998, we adopted the IC-based method as our standard practice for the ocular beam

  2. Guide for selection of dosimetry system for electron processing

    International Nuclear Information System (INIS)

    Mehta, K.

    1988-01-01

    Correct applications of radiation processing depend on accurate measurements of absorbed radiation dose. Radiation dosimetry plays several important roles in radiation processing. In particular, there are three stages for any radiation process during which dosimetry is a key to success: basic laboratory research, commissioning of the process and quality control. Radiation dosimeters may be divided into various classes depending upon their areas of applications and their relative quality: primary standard dosimeter, reference standard dosimeter, transfer standard dosimeter and routine in-house dosimeter. Several commercially available dosimeters are described under each class, and their advantages and limitations are discussed. Finally, recommendations are made as to which dosimeter is most suitable for each of the three stages of electron-beam processing. 124 refs

  3. The evidence base for the use of internal dosimetry in the clinical practice of molecular radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Strigari, Lidia [Regina Elena National Cancer Institute, Laboratory of Medical Physics and Expert Systems, Rome (Italy); Konijnenberg, Mark [Erasmus MC, Department of Nuclear Medicine, Rotterdam (Netherlands); Chiesa, Carlo [Instituto Nazionale Tumori, Department of Nuclear Medicine, Milan (Italy); Bardies, Manuel [UMR 1037 INSERM / Universite Paul Sabatier, Centre de Recherche en Cancerologie de Toulouse, Toulouse (France); Du, Yong [Royal Marsden NHS Foundation Trust, Department of Nuclear Medicine and PET/CT, Sutton, London (United Kingdom); Gleisner, Katarina Sjoegreen [Medical Radiation Physics, Clinical Sciences, Lund (Sweden); Lassmann, Michael [University of Wuerzburg, Department of Nuclear Medicine, Wuerzburg (Germany); Flux, Glenn [Royal Marsden NHS Foundation Trust and Institute of Cancer Research, Joint Department of Physics, Sutton (United Kingdom)

    2014-10-15

    Molecular radiotherapy (MRT) has demonstrated unique therapeutic advantages in the treatment of an increasing number of cancers. As with other treatment modalities, there is related toxicity to a number of organs at risk. Despite the large number of clinical trials over the past several decades, considerable uncertainties still remain regarding the optimization of this therapeutic approach and one of the vital issues to be answered is whether an absorbed radiation dose-response exists that could be used to guide personalized treatment. There are only limited and sporadic data investigating MRT dosimetry. The determination of dose-effect relationships for MRT has yet to be the explicit aim of a clinical trial. The aim of this article was to collate and discuss the available evidence for an absorbed radiation dose-effect relationships in MRT through a review of published data. Based on a PubMed search, 92 papers were found. Out of 79 studies investigating dosimetry, an absorbed dose-effect correlation was found in 48. The application of radiobiological modelling to clinical data is of increasing importance and the limited published data on absorbed dose-effect relationships based on these models are also reviewed. Based on National Cancer Institute guideline definition, the studies had a moderate or low rate of clinical relevance due to the limited number of studies investigating overall survival and absorbed dose. Nevertheless, the evidence strongly implies a correlation between the absorbed doses delivered and the response and toxicity, indicating that dosimetry-based personalized treatments would improve outcome and increase survival. (orig.)

  4. In-situ radiation dosimetry based on radio-fluorogenic co-polymerization

    International Nuclear Information System (INIS)

    Warman, John M; Luthjens, Leonard H; Haas, Matthijs P de

    2009-01-01

    A fluorimetric method of radiation dosimetry is presented for which the intensity of the fluorescence of a (tissue equivalent) medium is linearly dependent on accumulated dose from a few Gray up to kiloGrays. The method is based on radio-fluorogenic co-polymerization (RFCP) in which a normally very weakly fluorescent molecule becomes highly fluorescent when incorporated into a (radiation-initiated) growing polymer chain. The method is illustrated with results of in-situ measurements within the chamber of a cobalt-60 irradiator. It is proposed that RFCP could form the basis for fluorimetric multi-dimensional dose imaging.

  5. EPR Dosimetry - Present and Future

    Energy Technology Data Exchange (ETDEWEB)

    Regulla, D.F. [GSF - National Research Centre for Environment and Health, Institute of Radiation Protection, 85764 Neuherberg (Germany)

    1999-07-01

    In the past, IAEA has played a central role in stipulating research and development in EPR high-dose standardisation as well as in coordinating and organising international dose intercomparison programs, within the Member States of the United Nations from the mid-seventies till today. The future tasks of EPR dosimetry seem to tend towards different subjects such as bio markers, biological radiation effects, post-accident dose reconstruction in the environment, and retrospective human dosimetry. The latter may be considered a promising tool for epidemiology on the way to re-define radiation risk of man for chronicle radiation exposures, based on e.g. South Ural civil population and radiation workers. There are on-going international activities in the field of standardising high-level dosimetry by the American Standards on Testing and Materials (Astm), and by the International Organisation of Standards (ISO). The International Commission on Radiation Units and Measurements (ICRU) is considering the establishment of relevant recommendations concerning industrial radiation processing, but also human dose reconstruction. (Author)

  6. EPR Dosimetry - Present and Future

    International Nuclear Information System (INIS)

    Regulla, D.F.

    1999-01-01

    In the past, IAEA has played a central role in stipulating research and development in EPR high-dose standardisation as well as in coordinating and organising international dose intercomparison programs, within the Member States of the United Nations from the mid-seventies till today. The future tasks of EPR dosimetry seem to tend towards different subjects such as bio markers, biological radiation effects, post-accident dose reconstruction in the environment, and retrospective human dosimetry. The latter may be considered a promising tool for epidemiology on the way to re-define radiation risk of man for chronicle radiation exposures, based on e.g. South Ural civil population and radiation workers. There are on-going international activities in the field of standardising high-level dosimetry by the American Standards on Testing and Materials (Astm), and by the International Organisation of Standards (ISO). The International Commission on Radiation Units and Measurements (ICRU) is considering the establishment of relevant recommendations concerning industrial radiation processing, but also human dose reconstruction. (Author)

  7. MOSFET Dosimetry for Evaluation of Gonad Shielding during Radiotherapy

    International Nuclear Information System (INIS)

    Kim, Hwi Young; Choi, Yun Seok; Park, So Yeon; Park, Yang Kyun; Ye, Sung Joon

    2011-01-01

    In order to confirm feasibility of MOSFET modality in use of in vivo dosimetry, evaluation of gonad shielding in order to minimize gonadal dose of patients undergoing radiotherapy by using MOSFET modality was performed. Gonadal dose of patients undergoing radiotherapy for rectal cancer in the department of radiation oncology of Seoul National University Hospital since 2009 was measured. 6 MV and 15 MV photon beams emitted from Varian 21EX LINAC were used for radiotherapy. In order to minimize exposed dose caused by the scattered ray not only from collimator of LINAC but also from treatment region inside radiation field, we used box.shaped lead shielding material. The shielding material was made of the lead block and consists of 7.5 cm x 9.5 cm x 5.5 cm sized case and 9 cm x 9.5 cm x 1 cm sized cover. Dosimetry for evaluation of gonad shielding was done with MOSFET modality. By protecting with gonad shielding material, average gonadal dose of patients was decreased by 23.07% compared with reference dose outside of the shielding material. Average delivered gonadal dose inside the shielding material was 0.01 Gy. By the result of MOSFET dosimetry, we verified that gonadal dose was decreased by using gonad shielding material. In compare with TLD dosimetry, we could measure the exposed dose easily and precisely with MOSFET modality

  8. MOSFET Dosimetry for Evaluation of Gonad Shielding during Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hwi Young; Choi, Yun Seok; Park, So Yeon; Park, Yang Kyun [Seoul National University College of Medicine, Seoul (Korea, Republic of); Ye, Sung Joon [Seoul National University, Seoul (Korea, Republic of)

    2011-03-15

    In order to confirm feasibility of MOSFET modality in use of in vivo dosimetry, evaluation of gonad shielding in order to minimize gonadal dose of patients undergoing radiotherapy by using MOSFET modality was performed. Gonadal dose of patients undergoing radiotherapy for rectal cancer in the department of radiation oncology of Seoul National University Hospital since 2009 was measured. 6 MV and 15 MV photon beams emitted from Varian 21EX LINAC were used for radiotherapy. In order to minimize exposed dose caused by the scattered ray not only from collimator of LINAC but also from treatment region inside radiation field, we used box.shaped lead shielding material. The shielding material was made of the lead block and consists of 7.5 cm x 9.5 cm x 5.5 cm sized case and 9 cm x 9.5 cm x 1 cm sized cover. Dosimetry for evaluation of gonad shielding was done with MOSFET modality. By protecting with gonad shielding material, average gonadal dose of patients was decreased by 23.07% compared with reference dose outside of the shielding material. Average delivered gonadal dose inside the shielding material was 0.01 Gy. By the result of MOSFET dosimetry, we verified that gonadal dose was decreased by using gonad shielding material. In compare with TLD dosimetry, we could measure the exposed dose easily and precisely with MOSFET modality.

  9. Review of the correlation between results of cytogenetic dosimetry from blood lymphocytes and EPR dosimetry from tooth enamel for victims of radiation accidents

    International Nuclear Information System (INIS)

    Khvostunov, I.K.; Ivannikov, A.I.; Skvortsov, V.G.; Golub, E.V.; Nugis, V. Yu.

    2015-01-01

    The goal of this study was to compare dose estimates from electron paramagnetic resonance (EPR) dosimetry with teeth and cytogenetic dosimetry with blood lymphocytes for 30 victims of radiation accidents. The whole-body exposures estimated by tooth enamel EPR dosimetry were ranging from 0.01 to 9.3 Gy. Study group comprised victims exposed to acute and prolonged irradiation at high and low dose rate in different accidents. Blood samples were taken from each of them for cytogenetic analysis. Aberrations were scored and analysed according to International Atomic Energy Agency (IAEA) guidelines for conventional and FISH analysis. Tooth samples were collected in dental clinics after they had been extracted during ordinary practice. EPR dosimetry was performed according to the IAEA protocol. EPR dosimetry showed good correlation with dosimetry based on chromosomal analysis. All estimations of cytogenetic dose below detection limit coincide with EPR dose estimates within the ranges of uncertainty. The differences between cytogenetic and EPR assays may occur in a case of previous unaccounted exposure, non-homogeneous irradiation and due to contribution to absorbed dose from neutron irradiation. (authors)

  10. Possibilities and problems of modern dosimetry techniques in dentistry

    International Nuclear Information System (INIS)

    Regulla, D.F.

    Basic requirement for an optimized application of radiation in dentistry is a qualified dosimetry. The paper introduces into new dosimetry techniques based on solid state phenomena, such as luminescence an exoelectron emission, which, in case of dentistry, appear superior to conventional methods such as film and ionization chamber dosimetry. Advantages of the TLDs dosimeters, such as miniature detector volume, dynamic detection range, tissue equivalence etc., and their dosimetric possibilities are described together with hints on operational problems with respect to achieving high dosimetric measurement accuracy. (orig.) [de

  11. Development of a new software tool, based on ANN technology, in neutron spectrometry and dosimetry research

    International Nuclear Information System (INIS)

    Ortiz R, J.M.; Martinez B, M.R.; Vega C, H.R.

    2007-01-01

    Artificial Intelligence is a branch of study which enhances the capability of computers by giving them human-like intelligence. The brain architecture has been extensively studied and attempts have been made to emulate it as in the Artificial Neural Network technology. A large variety of neural network architectures have been developed and they have gained wide-spread popularity over the last few decades. Their application is considered as a substitute for many classical techniques that have been used for many years, as in the case of neutron spectrometry and dosimetry research areas. In previous works, a new approach called Robust Design of Artificial Neural network was applied to build an ANN topology capable to solve the neutron spectrometry and dosimetry problems within the Mat lab programming environment. In this work, the knowledge stored at Mat lab ANN's synaptic weights was extracted in order to develop for first time a customized software application based on ANN technology, which is proposed to be used in the neutron spectrometry and simultaneous dosimetry fields. (Author)

  12. Development of a new software tool, based on ANN technology, in neutron spectrometry and dosimetry research

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz R, J.M.; Martinez B, M.R.; Vega C, H.R. [Universidad Autonoma de Zacatecas, Av. Ramon Lopez Velarde 801, A.P. 336, 98000 Zacatecas (Mexico)

    2007-07-01

    Artificial Intelligence is a branch of study which enhances the capability of computers by giving them human-like intelligence. The brain architecture has been extensively studied and attempts have been made to emulate it as in the Artificial Neural Network technology. A large variety of neural network architectures have been developed and they have gained wide-spread popularity over the last few decades. Their application is considered as a substitute for many classical techniques that have been used for many years, as in the case of neutron spectrometry and dosimetry research areas. In previous works, a new approach called Robust Design of Artificial Neural network was applied to build an ANN topology capable to solve the neutron spectrometry and dosimetry problems within the Mat lab programming environment. In this work, the knowledge stored at Mat lab ANN's synaptic weights was extracted in order to develop for first time a customized software application based on ANN technology, which is proposed to be used in the neutron spectrometry and simultaneous dosimetry fields. (Author)

  13. The United Kingdom's radiotherapy dosimetry audit network

    International Nuclear Information System (INIS)

    Thwaites, D.I.; Allahverdi, M.; Powley, S.K.; Nisbet, A.

    2003-01-01

    The first comprehensive national dosimetry intercomparison in the United Kingdom involving all UK radiotherapy centres was carried out in the late 1980s. Out of this a regular radiotherapy dosimetry audit network evolved in the early 1990s. The network is co-ordinated by the Institute of Physics and Engineering in Medicine and comprises eight co-operative regional groups. Audits are based on site visits using ionization chambers and epoxy resin water substitute phantoms. The basic audit methodology and phantom design follows that of the original national intercomparison exercise. However, most of the groups have evolved more complex methods, to extend the audit scope to include other parameters, other parts of the radiotherapy process and other treatment modalities. A number of the groups have developed phantoms to simulate various clinical treatment situations, enabling the sharing of phantoms and expertise between groups, but retaining a common base. Besides megavoltage external beam photon dosimetry, a number of the groups have also included the audit of kilovoltage X ray beams, electron beams and brachytherapy dosimetry. The National Physical Laboratory is involved in the network and carries out basic beam calibration audits to link the groups. The network is described and the methods and results are illustrated using the Scottish+ group as an example. (author)

  14. Fast neutron spectrometry and dosimetry; Spectrometrie et dosimetrie des neutrons rapides

    Energy Technology Data Exchange (ETDEWEB)

    Blaize, S; Ailloud, J; Mariani, J; Millot, J P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    We have studied fast neutron spectrometry and dosimetry through the recoil protons they produce in hydrogenated samples. In spectrometric, we used nuclear emulsions, in dosimetric, we used polyethylene coated with zinc sulphide and placed before a photomultiplier. (author)Fren. [French] Nous avons etudie la spectrometrie et la dosimetrie des neutrons rapides en utilisant les protons de recul qu'ils produisent dans une matiere hydrogenee. En spectrometrie, nous avons employe des emulsions nucleaires, en dosimetrie, du polyethylene recouvert de sulfure de zinc place devant un photomultiplicateur. (auteur)

  15. Dosimetry Control: Technic and methods. Proceedings of the international workshop 'Actual problems of dosimetry'

    International Nuclear Information System (INIS)

    Lyutsko, A.M.; Nesterenko, V.B.; Chudakov, V.A.; Konoplya, E.F.; Milyutin, A.A.

    1997-10-01

    There is a number of unsolved problems of both dosimetric and radiometric control, questions of the biological dosimetry, reconstruction of dozes of irradiation of the population at radiation incidents, which require coordination of efforts of scientists in various areas of a science. The submitted materials are grouped on five units: dosimetry engineering, biological dosimetry and markers of radiation impact, dosimetry of a medical irradiation, normative and measurement assurance of the dosimetric control, monitoring and reconstruction of dozes at radiation incidents

  16. Neutron Reference Benchmark Field Specifications: ACRR Polyethylene-Lead-Graphite (PLG) Bucket Environment (ACRR-PLG-CC-32-CL).

    Energy Technology Data Exchange (ETDEWEB)

    Vega, Richard Manuel [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Parm, Edward J. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Griffin, Patrick J. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Vehar, David W. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)

    2015-07-01

    This report was put together to support the International Atomic Energy Agency (IAEA) REAL- 2016 activity to validate the dosimetry community’s ability to use a consistent set of activation data and to derive consistent spectral characterizations. The report captures details of integral measurements taken in the Annular Core Research Reactor (ACRR) central cavity with the Polyethylene-Lead-Graphite (PLG) bucket, reference neutron benchmark field. The field is described and an “a priori” calculated neutron spectrum is reported, based on MCNP6 calculations, and a subject matter expert (SME) based covariance matrix is given for this “a priori” spectrum. The results of 37 integral dosimetry measurements in the neutron field are reported.

  17. Non-conventional personal dosimetry techniques

    International Nuclear Information System (INIS)

    Regulla, D.F.

    1984-01-01

    Established dosimetry has achieved a high standard in personnel monitoring. This applies particularly to photon dosimetry. Nevertheless, even in photon dosimetry, improvements and changes are being made. The reason may be technological progress, or the introduction of new tasks on the basis of the recommendations of international bodies (e.g. the new ICRU measurement unit) of national legislation. Since we are restricting ourselves here to technical trends the author would like to draw attention to various activities of current interest, e.g. the computation of receptor-related conversion coefficients from personal dose to organ or body doses, taking into account the conditions of exposure with respect to differential energy and angular distribution of the radiation field. Realistic data on exposure geometry are taken from work place analyses. Furthermore, the data banks of central personal dosimetry services are subject to statistical evaluation and radiation protection trend analysis. Technological progress and developments are considered from the point of view of personal dosimetry, partial body or extremity dosimetry and accidental dosimetry

  18. Dosimetry and Calibration Section

    International Nuclear Information System (INIS)

    Otto, T.

    1999-01-01

    The Dosimetry and Calibration Section fulfils two tasks within CERN's Radiation Protection Group: the Individual Dosimetry Service monitors more than 5000 persons potentially exposed to ionizing radiation on the CERN sites, and the Calibration Laboratory verifies throughout the year, at regular intervals, over 1000 instruments, monitors, and electronic dosimeters used by RP Group. The establishment of a Quality Assurance System for the Individual Dosimetry Service, a requirement of the new Swiss Ordinance for personal dosimetry, put a considerable workload on the section. Together with an external consultant it was decided to identify and then describe the different 'processes' of the routine work performed in the dosimetry service. The resulting Quality Manual was submitted to the Federal Office for Public Health in Bern in autumn. The CERN Individual Dosimetry Service will eventually be officially endorsed after a successful technical test in March 1999. On the technical side, the introduction of an automatic development machine for gamma films was very successful. It processes the dosimetric films without an operator being present, and its built-in regeneration mechanism keeps the concentration of the processing chemicals at a constant level

  19. Dosimetry for radiation processing

    International Nuclear Information System (INIS)

    McLaughlin, W.L.; Boyd, A.W.; Chadwick, K.H.; McDonald, J.C.; Miller, A.

    1989-01-01

    Radiation processing is a relatively young industry with broad applications and considerable commercial success. Dosimetry provides an independent and effective way of developing and controlling many industrial processes. In the sterilization of medical devices and in food irradiation, where the radiation treatment impacts directly on public health, the measurements of dose provide the official means of regulating and approving its use. In this respect, dosimetry provides the operator with a means of characterizing the facility, of proving that products are treated within acceptable dose limits and of controlling the routine operation. This book presents an up-to-date review of the theory, data and measurement techniques for radiation processing dosimetry in a practical and useful way. It is hoped that this book will lead to improved measurement procedures, more accurate and precise dosimetry and a greater appreciation of the necessity of dosimetry for radiation processing. (author)

  20. Monte Carlo simulations to replace film dosimetry in IMRT verification

    International Nuclear Information System (INIS)

    Goetzfried, Thomas; Trautwein, Marius; Koelbi, Oliver; Bogner, Ludwig; Rickhey, Mark

    2011-01-01

    Patient-specific verification of intensity-modulated radiation therapy (IMRT) plans can be done by dosimetric measurements or by independent dose or monitor unit calculations. The aim of this study was the clinical evaluation of IMRT verification based on a fast Monte Carlo (MC) program with regard to possible benefits compared to commonly used film dosimetry. 25 head-and-neck IMRT plans were recalculated by a pencil beam based treatment planning system (TPS) using an appropriate quality assurance (QA) phantom. All plans were verified both by film and diode dosimetry and compared to MC simulations. The irradiated films, the results of diode measurements and the computed dose distributions were evaluated, and the data were compared on the basis of gamma maps and dose-difference histograms. Average deviations in the high-dose region between diode measurements and point dose calculations performed with the TPS and MC program were 0.7 ± 2.7% and 1.2 ± 3.1%, respectively. For film measurements, the mean gamma values with 3% dose difference and 3 mm distance-to-agreement were 0.74 ± 0.28 (TPS as reference) with dose deviations up to 10%. Corresponding values were significantly reduced to 0.34 ± 0.09 for MC dose calculation. The total time needed for both verification procedures is comparable, however, by far less labor intensive in the case of MC simulations. The presented study showed that independent dose calculation verification of IMRT plans with a fast MC program has the potential to eclipse film dosimetry more and more in the near future. Thus, the linac-specific QA part will necessarily become more important. In combination with MC simulations and due to the simple set-up, point-dose measurements for dosimetric plausibility checks are recommended at least in the IMRT introduction phase. (orig.)

  1. Radiation dosimetry and standards at the austrian dosimetry laboratory

    International Nuclear Information System (INIS)

    Leitner, A.

    1984-10-01

    The Austrian Dosimetry Laboratory, established and operated in cooperation between the Austrian Research Center Seibersdorf and the Federal Office of Metrology and Surveying (Bundesamt and Eich- und Vermessungswesen) maintains the national primary standards for radiation dosimetry. Furthermore its tasks include routine calibration of dosemeters and dosimetric research. The irradiation facilities of the laboratory comprise three X-ray machines covering the voltage range from 5 kV to 420 kV constant potential, a 60 Co teletherapy unit, a circular exposure system for routine batch calibration of personnel dosemeters with four gamma ray sources ( 60 Co and 137 Cs) and a reference source system with six gamma ray sources ( 60 Co and 137 Cs). In addition a set of calibrated beta ray sources are provided ( 147 Pm, 204 Tl and 90 Sr). The dosimetric equipment consists of three free-air parallelplate ionization chambers serving as primary standards of exposure for the X-ray energy region, graphite cavity chambers with measured volume as primary standards for the gamma radiation of 137 Cs and 60 Co as well as different secondary standard ionization chambers covering the dose rate range from the natural background level up to the level of modern therapy accelerators. In addition for high energy photon and electron radiation a graphite calorimeter is provided as primary standard of absorbed dose. The principle experimental set-ups for the practical use of the standards are presented and the procedures for the calibration of the different types of dosemeters are described. (Author)

  2. Thin film tritium dosimetry

    Science.gov (United States)

    Moran, Paul R.

    1976-01-01

    The present invention provides a method for tritium dosimetry. A dosimeter comprising a thin film of a material having relatively sensitive RITAC-RITAP dosimetry properties is exposed to radiation from tritium, and after the dosimeter has been removed from the source of the radiation, the low energy electron dose deposited in the thin film is determined by radiation-induced, thermally-activated polarization dosimetry techniques.

  3. Nineteenth nuclear accident dosimetry intercomparison study, August 9-13, 1982

    International Nuclear Information System (INIS)

    Greene, R.T.; Sims, C.C.; Swaja, R.E.

    1983-11-01

    The Nineteenth Nuclear Accident Dosimetry Intercomparison Study was held August 9 to 13, 1982, at the Oak Ridge National Laboratory using the Health Physics Research Reactor operated in the pulse mode to simulate nuclear criticality accidents. Participants from eight organizations measured neutron and gamma doses at air stations and on phantoms for three different shielding conditions. Measured results were compared to nuclear industry guidelines for criticality accident dosimeters which suggest accuracies of +-25% for neutron dose and +-20% for gamma dose. Seventy-two percent of the neutron dose measurements using foil activation, sodium activation, hair sulfur activation, and thermoluminescent methods met the guidelines while less than 40% of the gamma dose measurements were within +-20% of reference values. The softest neutron energy spectrum (also lowest neutron/gamma dose ratio) provided the most difficulty in measuring neutron and gamma doses. Results of this study indicate the need for continued intercomparison and testing of nuclear accident dosimetry systems and for training of evaluating personnel. 14 references, 7 figures, 16 tables

  4. Computational methods in several fields of radiation dosimetry

    International Nuclear Information System (INIS)

    Paretzke, Herwig G.

    2010-01-01

    Full text: Radiation dosimetry has to cope with a wide spectrum of applications and requirements in time and size. The ubiquitous presence of various radiation fields or radionuclides in the human home, working, urban or agricultural environment can lead to various dosimetric tasks starting from radioecology, retrospective and predictive dosimetry, personal dosimetry, up to measurements of radionuclide concentrations in environmental and food product and, finally in persons and their excreta. In all these fields measurements and computational models for the interpretation or understanding of observations are employed explicitly or implicitly. In this lecture some examples of own computational models will be given from the various dosimetric fields, including a) Radioecology (e.g. with the code systems based on ECOSYS, which was developed far before the Chernobyl reactor accident, and tested thoroughly afterwards), b) Internal dosimetry (improved metabolism models based on our own data), c) External dosimetry (with the new ICRU-ICRP-Voxelphantom developed by our lab), d) Radiation therapy (with GEANT IV as applied to mixed reactor radiation incident on individualized voxel phantoms), e) Some aspects of nanodosimetric track structure computations (not dealt with in the other presentation of this author). Finally, some general remarks will be made on the high explicit or implicit importance of computational models in radiation protection and other research field dealing with large systems, as well as on good scientific practices which should generally be followed when developing and applying such computational models

  5. The Mayak Worker Dosimetry System (MWDS-2013): implementation of the dose calculations

    International Nuclear Information System (INIS)

    Zhdanov, A.; Vostrotin, V.; Efimov, A.; Birchall, A.; Puncher, M.

    2017-01-01

    The calculation of internal doses for the Mayak Worker Dosimetry System (MWDS-2013) involved extensive computational resources due to the complexity and sheer number of calculations required. The required output consisted of a set of 1000 hyper-realizations: each hyper-realization consists of a set (1 for each worker) of probability distributions of organ doses. This report describes the hardware components and computational approaches required to make the calculation tractable. Together with the software, this system is referred to here as the 'PANDORA system'. It is based on a commercial SQL server database in a series of six work stations. A complete run of the entire Mayak worker cohort entailed a huge amount of calculations in PANDORA and due to the relatively slow speed of writing the data into the SQL server, each run took about 47 days. Quality control was monitored by comparing doses calculated in PANDORA with those in a specially modified version of the commercial software 'IMBA Professional Plus'. Suggestions are also made for increasing calculation and storage efficiency for future dosimetry calculations using PANDORA. (authors)

  6. Automatic neutron dosimetry system based on fluorescent nuclear track detector technology

    International Nuclear Information System (INIS)

    Akselrod, M.S.; Fomenko, V.V.; Bartz, J.A.; Haslett, T.L.

    2014-01-01

    For the first time, the authors are describing an automatic fluorescent nuclear track detector (FNTD) reader for neutron dosimetry. FNTD is a luminescent integrating type of detector made of aluminium oxide crystals that does not require electronics or batteries during irradiation. Non-destructive optical readout of the detector is performed using a confocal laser scanning fluorescence imaging with near-diffraction limited resolution. The fully automatic table-top reader allows one to load up to 216 detectors on a tray, read their engraved IDs using a CCD camera and optical character recognition, scan and process simultaneously two types of images in fluorescent and reflected laser light contrast to eliminate false-positive tracks related to surface and volume crystal imperfections. The FNTD dosimetry system allows one to measure neutron doses from 0.1 mSv to 20 Sv and covers neutron energies from thermal to 20 MeV. The reader is characterised by a robust, compact optical design, fast data processing electronics and user-friendly software. The first table-top automatic FNTD neutron dosimetry system was successfully tested for LLD, linearity and ability to measure neutrons in mixed neutron-photon fields satisfying US and ISO standards. This new neutron dosimetry system provides advantages over other technologies including environmental stability of the detector material, wide range of detectable neutron energies and doses, detector re-readability and re-usability and all-optical readout. A new adaptive image processing algorithm reliably removes false-positive tracks associated with surface and bulk crystal imperfections. (authors)

  7. Fundamentals of x-ray dosimetry

    International Nuclear Information System (INIS)

    Roesch, W.C.

    1976-01-01

    Fundamental information about x-ray dosimetry is presented. Definitions are given and expanded on for dose, absorbed dose including microdosimetry, radiation physics (properties of the radiation that are important to dosimetry), and dosimetry (how the properties are dealt with in determining dose). 5 figs, 12 refs

  8. Use of the GATE Monte Carlo package for dosimetry applications

    Energy Technology Data Exchange (ETDEWEB)

    Visvikis, D. [INSERM U650, LaTIM, University Hospital Medical School, F 29609 Brest (France)]. E-mail: Visvikis.Dimitris@univ-brest.fr; Bardies, M. [INSERM U601, CHU Nantes, F 44093 Nantes (France); Chiavassa, S. [INSERM U601, CHU Nantes, F 44093 Nantes (France); Danford, C. [Department of Medical Physics, MSKCC, New York (United States); Kirov, A. [Department of Medical Physics, MSKCC, New York (United States); Lamare, F. [INSERM U650, LaTIM, University Hospital Medical School, F 29609 Brest (France); Maigne, L. [Departement de Curietherapie-Radiotherapie, Centre Jean Perrin, F 63000 Clemont-Ferrand (France); Staelens, S. [UGent-ELIS, St-Pietersnieuwstraat, 41, B 9000 Gent (Belgium); Taschereau, R. [CRUMP Institute for Molecular Imaging, UCLA, Los Angeles (United States)

    2006-12-20

    One of the roles for Monte Carlo (MC) simulation studies is in the area of dosimetry. A number of different codes dedicated to dosimetry applications are available and widely used today, such as MCNP, EGSnrc and PTRAN. However, such codes do not easily facilitate the description of complicated 3D sources or emission tomography systems and associated data flow, which may be useful in different dosimetry application domains. Such problems can be overcome by the use of specific MC codes such as GATE (GEANT4 Application to Tomographic Emission), which is based on Geant4 libraries, providing a scripting interface with a number of advantages for the simulation of SPECT and PET systems. Despite this potential, its major disadvantage is in terms of efficiency involving long execution times for applications such as dosimetry. The strong points and disadvantages of GATE in comparison to other dosimetry specific codes are discussed and illustrated in terms of accuracy, efficiency and flexibility. A number of features, such as the use of voxelised and moving sources, as well as developments such as advanced visualization tools and the development of dose estimation maps allowing GATE to be used for dosimetry applications are presented. In addition, different examples from dosimetry applications with GATE are given. Finally, future directions with respect to the use of GATE for dosimetry applications are outlined.

  9. Dosimetry characteristics of the Leksell gamma knife for stereotactic radiosurgery

    International Nuclear Information System (INIS)

    Wu, A.; Lindner, G.; Maitz, A.; Smarra, N.; Turco, R.F.; Kalend, A.M.; Lunsford, L.D.; Flickinger, J.C.; Bloomer, W.D.

    1988-01-01

    Gamma knife radiosurgery refers to the treatment procedure that delivers very high dose to a small brain lesion with 201 highly focused beams of Co-60. The hemispheric array of these multiple sources with the sizes of beams ranging from 4, 8, 14, to 18 mm makes the determination of dosimetry characteristics of the radiation field very complex. This paper describes the structures, operations, and dose characteristics of gamma knife. Dosimetry measurements were made using ion chamber, TLD, diode, and films to calibrate the dose outputs of the combination of 201 beams of 4, 8, 14, or 18 mm in diameter irradiating from various directions. Results of measured isodose distribution and dose profiles for the various diameter beams are also presented

  10. Thermoluminescent dosimetry in veterinary diagnostic radiology

    International Nuclear Information System (INIS)

    Hernández-Ruiz, L.; Jimenez-Flores, Y.; Rivera-Montalvo, T.; Arias-Cisneros, L.; Méndez-Aguilar, R.E.; Uribe-Izquierdo, P.

    2012-01-01

    This paper presents the results of Environmental and Personnel Dosimetry made in a radiology area of a veterinary hospital. Dosimetry was realized using thermoluminescent (TL) materials. Environmental Dosimetry results show that areas closer to the X-ray equipment are safe. Personnel Dosimetry shows important measurements of daily workday in some persons near to the limit established by ICRP. TL results of radiation measurement suggest TLDs are good candidates as a dosimeter to radiation dosimetry in veterinary radiology. - Highlights: ► Personnel dosimetry in laboratory veterinary diagnostic was determined. ► Student workplaces are safe against radiation. ► Efficiency value of apron lead was determined. ► X-ray beams distribution into veterinarian laboratory was measured.

  11. EPR dosimetry - present and future

    International Nuclear Information System (INIS)

    Regulla, D.F.

    1999-01-01

    In the past, IAEA has played a central role in stipulating research and development in EPR high-dose standardisation as well as co-ordinating and organising international dose intercomparison programs, within the Member States of the United Nations from the mid-seventies till today. The future tasks of EPR dosimetry seem to tend towards different subjects such as biomarkers, biological radiation effects, post-accident dose reconstruction in the environment, and retrospective human dosimetry. The latter may be considered a promising tool for epidemiology on the way to re-define radiation risk of man for chronicle radiation exposures, based on e.g. South Ural civil population and radiation workers. There are on-going international activities in the field of standardising high-level dosimetry by the American Standards on Testing and Materials (ASTM), and the International Organisation of Standards (ISO) as well as those of the International Commission on Radiation Units and Measurements (ICRU) considering the establishment of relevant recommendations concerning industrial radiation processing, but also human dose reconstruction. (author)

  12. Sixth symposium on neutron dosimetry

    International Nuclear Information System (INIS)

    1987-01-01

    This booklet contains all abstracts of papers presented in 13 sessions. Main topics: Cross sections and Kerma factors; analytical radiobiology; detectors for personnel monitoring; secondary charged particles and microdosimetric basis of q-value for neutrons; personnel dosimetry; concepts for radiation protection; ambient monitoring; TEPC and ion chambers in radiation protection; beam dosimetry; track detectors (CR-39); dosimetry at biomedical irradiation facilities; health physics at therapy facilities; calibration for radiation protection; devices for beam dosimetry (TLD and miscellaneous); therapy and biomedical irradiation facilities; treatment planning. (HP)

  13. Environmental dosimetry

    International Nuclear Information System (INIS)

    Gold, R.

    1977-01-01

    For more than 60 years, natural radiation has offered broad opportunities for basic research as evidenced by many fundamental discoveries. Within the last decade, however, dramatic changes have occurred in the motivation and direction of this research. The urgent need for economical energy sources entailing acceptably low levels of environmental impact has compelled the applied aspects of our radiation environment to become overriding considerations. It is within this general framework that state-of-the-art environmental dosimetry techniques are reviewed. Although applied motivation and relevance underscores the current milieu for both reactor and environmental dosimetry, a perhaps even more unifying force is the broad similarity of reactor and environmental radiation fields. In this review, a comparison of these two mixed radiation fields is presented stressing the underlying similarities that exist. On this basis, the evolution of a strong inner bond between dosimetry methods for both reactor and environmental radiation fields is described. The existence of this bond will be illustrated using representative examples of observed spectra. Dosimetry methods of particularly high applicability for both of these fields are described. Special emphasis is placed on techniques of high sensitivity and absolute accuracy which are capable of resolving the components of these mixed radiation fields

  14. Nuclear accident dosimetry

    International Nuclear Information System (INIS)

    1982-01-01

    The film presents statistical data on criticality accidents. It outlines past IAEA activities on criticality accident dosimetry and the technical documents that resulted from this work. The film furthermore illustrates an international comparison study on nuclear accident dosimetry conducted at the Atomic Energy Research Establishment, Harwell, United Kingdom

  15. Nuclear accident dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1983-12-31

    The film presents statistical data on criticality accidents. It outlines past IAEA activities on criticality accident dosimetry and the technical documents that resulted from this work. The film furthermore illustrates an international comparison study on nuclear accident dosimetry conducted at the Atomic Energy Research Establishment, Harwell, United Kingdom

  16. T2*-weighted image/T2-weighted image fusion in postimplant dosimetry of prostate brachytherapy

    International Nuclear Information System (INIS)

    Katayama, Norihisa; Takemoto, Mitsuhiro; Yoshio, Kotaro

    2011-01-01

    Computed tomography (CT)/magnetic resonance imaging (MRI) fusion is considered to be the best method for postimplant dosimetry of permanent prostate brachytherapy; however, it is inconvenient and costly. In T2 * -weighted image (T2 * -WI), seeds can be easily detected without the use of an intravenous contrast material. We present a novel method for postimplant dosimetry using T2 * -WI/T2-weighted image (T2-WI) fusion. We compared the outcomes of T2 * -WI/T2-WI fusion-based and CT/T2-WI fusion-based postimplant dosimetry. Between April 2008 and July 2009, 50 consecutive prostate cancer patients underwent brachytherapy. All the patients were treated with 144 Gy of brachytherapy alone. Dose-volume histogram (DVH) parameters (prostate D90, prostate V100, prostate V150, urethral D10, and rectal D2cc) were prospectively compared between T2 * -WI/T2-WI fusion-based and CT/T2-WI fusion-based dosimetry. All the DVH parameters estimated by T2 * -WI/T2-WI fusion-based dosimetry strongly correlated to those estimated by CT/T2-WI fusion-based dosimetry (0.77≤ R ≤0.91). No significant difference was observed in these parameters between the two methods, except for prostate V150 (p=0.04). These results show that T2 * -WI/T2-WI fusion-based dosimetry is comparable or superior to MRI-based dosimetry as previously reported, because no intravenous contrast material is required. For some patients, rather large differences were observed in the value between the 2 methods. We thought these large differences were a result of seed miscounts in T2 * -WI and shifts in fusion. Improving the image quality of T2 * -WI and the image acquisition speed of T2 * -WI and T2-WI may decrease seed miscounts and fusion shifts. Therefore, in the future, T2 * -WI/T2-WI fusion may be more useful for postimplant dosimetry of prostate brachytherapy. (author)

  17. Performance testing of dosimetry processors, status of NRC rulemaking for improved personnel dosimetry processing, and some beta dosimetry and instrumentation problems observed by NRC regional inspectors

    International Nuclear Information System (INIS)

    Dennis, N.A.; Kinneman, J.D.; Costello, F.M.; White, J.R.; Nimitz, R.L.

    1983-01-01

    Early dosimetry processor performance studies conducted between 1967 and 1979 by several different investigators indicated that a significant percentage of personnel dosimetry processors may not be performing with a reasonable degree of accuracy. Results of voluntary performance testing of US personnel dosimetry processors against the final Health Physics Society Standard, Criteria for Testing Personnel Dosimetry Performance by the University of Michigan for the Nuclear Regulatory Commission (NRC) will be summarized with emphasis on processor performance in radiation categories involving beta particles and beta particles and photon mixtures. The current status of the NRC's regulatory program for improved personnel dosimetry processing will be reviewed. The NRC is proposing amendments to its regulations, 10 CFR Part 20, that would require its licensees to utilize specified personnel dosimetry services from processors accredited by the National Voluntary Laboratory Accreditation Program of the National Bureau of Standards. Details of the development and schedule for implementation of the program will be highlighted. Finally, selected beta dosimetry and beta instrumentation problems observed by NRC Regional Staff during inspections of NRC licensed facilities will be discussed

  18. Tenth DOE workshop on personnel neutron dosimetry

    International Nuclear Information System (INIS)

    1984-06-01

    The purpose of this workshop is to promote the international exchange of information on neutron dosimetry. The development of an accurate real-time dosemeter is an immediate need which must be met. Assessment of the neutron dose equivalent at low doses with a reasonable degree of accuracy must be accomplished to provide validity to exposure records. These and other aspects of personal neutron dosimetry are discussed. Separate abstracts have been prepared for each paper for inclusion in the Energy Data Base

  19. High Energy Electron Dosimetry by Alanine/ESR Spectroscopy

    International Nuclear Information System (INIS)

    Chu, Sung Sil

    1989-01-01

    Dosimetry based on electron spin resonance(ESR) analysis of radiation induced free radicals in amino acids is relevant to biological dosimetry applications. Alanine detectors are without walls and are tissue equivalent. Therefore, alanine ESR dosimetry looks promising for use in the therapy level. The dose range of the alanine/ESR dosimetry system can be extended down to l Gy. In a water phantom the absorbed dose of electrons generated by a medical linear accelerator of different initial energies (6-21 MeV) and therapeutic dose levels(1-60 Gy) was measured. Furthermore, depth dose measurements carried out with alanine dosimeters were compared with ionization chamber measurements. As the results, the measured absorbed doses for shallow depth of initial electron energies above 15 MeV were higher by 2-5% than those calculated by nominal energy CE factors. This seems to be caused by low energy scattered beams generated from the scattering foil and electron cones of beam projecting device in medical linear accelerator

  20. Dosimetry in Diagnostic Radiology for Paediatric Patients

    International Nuclear Information System (INIS)

    2013-01-01

    Concern about the radiation dose to children from diagnostic radiology examinations has recently been popularly expressed, particularly as related to computed tomography (CT) procedures. This involves the observation that children can receive doses far in excess of those delivered to adults, in part due to the digital nature of the image receptors that may give no warning to the operator of the dose to the patient. Concern for CT examinations should be extended to the broad range of paediatric diagnostic radiological procedures responsible for radiation doses in children, especially as factors, such as increased radiosensitivity and the longer life expectancy of children, increase the associated radiation risk. In all cases, owing to the added paediatric radiological examination factor of patient size and its associated impact on equipment selection, clinical examination protocol and dosimetric audit, the determination of paediatric dose requires a distinct approach from adult dosimetry associated with diagnostic radiological examinations. In response to this, there is a need to inform health professionals about standardized methodologies used to determine paediatric dose for all major modalities such as general radiography, fluoroscopy and CT. Methodologies for standardizing the conduct of dose audits and their use for the derivation and application of diagnostic reference levels for patient populations, that vary in size, are also required. In addition, a review is needed of the current knowledge on risks specific to non-adults from radiation, and also an analysis of the management of factors contributing to dose from paediatric radiological examinations. In 2007, the IAEA published a code of practice, Dosimetry in Diagnostic Radiology: An International Code of Practice, as Technical Reports Series No. 457 (TRS 457). TRS 457 recommends procedures for dosimetric measurement and calibration for the attainment of standardized dosimetry, and addresses requirements

  1. SU-C-201-07: Towards Clinical Cherenkov Emission Dosimetry: Stopping Power-To-Cherenkov Power Ratios and Beam Quality Specification of Clinical Electron Beams

    International Nuclear Information System (INIS)

    Zlateva, Y; Seuntjens, J; El Naqa, I

    2016-01-01

    Purpose: We propose a Cherenkov emission (CE)-based reference dosimetry method, which in contrast to ionization chamber-based dosimetry, employs spectrum-averaged electron restricted mass collision stopping power-to-Cherenkov power ratios (SCRs), and we examine Monte Carlo-calculated SCRs and beam quality specification of clinical electron beams. Methods: The EGSnrc user code SPRRZnrc was modified to compute SCRs instead of stopping-power ratios (single medium: water; cut-off: CE threshold (observing Spencer-Attix conditions); CE power: Frank-Tamm). SCRs are calculated with BEAMnrc for realistic electron beams with nominal energies of 6–22 MeV from three Varian accelerators (TrueBeam Clinac 21EX, Clinac 2100C/D) and for mono-energetic beams of energies equal to the mean electron energy at the water surface. Sources of deviation between clinical and mono-energetic SCRs are analyzed quantitatively. A universal fit for the beam-quality index R_5_0 in terms of the depth of 50% CE C_5_0 is carried out. Results: SCRs at reference depth are overestimated by mono-energetic values by up to 0.2% for a 6-MeV beam and underestimated by up to 2.3% for a 22-MeV beam. The variation is mainly due to the clinical beam spectrum and photon contamination. Beam angular spread has a small effect across all depths and energies. The influence of the electron spectrum becomes increasingly significant at large depths, while at shallow depths and high beam energies photon contamination is predominant (up to 2.0%). The universal data fit reveals a strong linear correlation between R_5_0 and C_5_0 (ρ > 0.99999). Conclusion: CE is inherent to radiotherapy beams and can be detected outside the beam with available optical technologies, which makes it an ideal candidate for out-of-beam high-resolution 3D dosimetry. Successful clinical implementation of CE dosimetry hinges on the development of robust protocols for converting measured CE to radiation dose. Our findings constitute a key step

  2. Individualised {sup 177}Lu-DOTATATE treatment of neuroendocrine tumours based on kidney dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Sundloev, Anna; Tennvall, Jan [Lund University, Department of Oncology and Pathology, Clinical Sciences, Lund (Sweden); Skaane University Hospital, Department of Oncology, Lund (Sweden); Sjoegreen-Gleisner, Katarina; Ljungberg, Michael [Lund University, Department of Medical Radiation Physics, Clinical Sciences, Lund (Sweden); Svensson, Johanna [Sahlgrenska University Hospital, Department of Oncology, Gothenburg (Sweden); Olsson, Tomas [Skaane University Hospital, Department of Oncology, Lund (Sweden); Bernhardt, Peter [University of Gothenburg, Department of Radiation Physics, Gothenburg (Sweden); Sahlgrenska University Hospital, Department of Medical Physics and Biomedical Engineering, Gothenburg (Sweden)

    2017-08-15

    To present data from an interim analysis of a Phase II trial designed to determine the feasibility, safety, and efficacy of individualising treatment based on renal dosimetry, by giving as many cycles as possible within a maximum renal biologically effective dose (BED). Treatment was given with repeated cycles of 7.4 GBq {sup 177}Lu-DOTATATE at 8-12-week intervals. Detailed dosimetry was performed in all patients after each cycle using a hybrid method (SPECT + planar imaging). All patients received treatment up to a renal BED of 27 ± 2 Gy (α/β = 2.6 Gy) (Step 1). Selected patients were offered further treatment up to a renal BED of 40 ± 2 Gy (Step 2). Renal function was followed by estimation and measurement of the glomerular filtration rate (GFR). Fifty-one patients were included in the present analysis. Among the patients who received treatment as planned, the median number of cycles in Step 1 was 5 (range 3-7), and for those who completed Step 2 it was 7 (range 5-8); 73% were able to receive >4 cycles. Although GFR decreased in most patients after the completion of treatment, no grade 3-4 toxicity was observed. Patients with a reduced baseline GFR seemed to have an increased risk of GFR decline. Five patients received treatment in Step 2, none of whom exhibited a significant reduction in renal function. Individualising PRRT using renal dosimetry seems feasible and safe and leads to an increased number of cycles in the majority of patients. The trial will continue as planned. (orig.)

  3. Dosimetry for radiation processing. Final report of the co-ordinated research project on characterization and evaluation of high dose dosimetry techniques for quality assurance in radiation processing

    International Nuclear Information System (INIS)

    2000-06-01

    In many Member States the use of large cobalt-60 gamma ray facilities and electron beam accelerators with beam energies from about 0.1 to 10 MeV for industrial processing continues to increase. For these processes, quality assurance relies on the application of well established dosimetry systems and procedures. This is especially the case for health regulated processes, such as the radiation sterilization of health care products, and the irradiation of food to eliminate pathogenic organisms or to control insect pests. A co-ordinated research project (CRP) was initiated by the IAEA in June 1995. Research contracts and research agreements in areas of high dose dosimetry were initiated to meet these challenges. The major goals of this CRP were to investigate the parameters that influence the response of dosimeters and to develop reference and transfer dosimetry techniques, especially for electron beams of energy less than 4 MeV and for high energy X ray sources (up to 5 MV). These will help to unify the radiation measurements performed by different radiation processing facilities and other high dose dosimetry users in Member States and encourage efforts to obtain traceability to primary and secondary standards laboratories. It will also aim to strengthen and expand the present International Dose Assurance Service (IDAS) provided by the IAEA

  4. SFPM opinion on the so-called 'transit' in vivo dosimetry in external radiotherapy

    International Nuclear Information System (INIS)

    Berger, Lucie; Dupuis, Pauline; Marchesi, Vincent; Boutry, Christine; Francois, Pascal; Crespin, Sylvain

    2014-01-01

    Written to the demand of the ASN to the SFPM (the French professional body in medical physics), this report states the opinion of these professionals regarding the use of the so-called 'transit' dosimetry for the control of the in vivo dose received during radiotherapy. After an overview of the use of in vivo dosimetry in medical practices, the authors outline the main benefits and drawbacks of point conventional detectors used for this dosimetry. They propose an overview of the state-of-the-art in transit in vivo dosimetry by briefly describing the different developed methodologies: the prediction-based methodology and the rear projection methodology. They also propose a literature review on transit in vivo dosimetry. Based on expert experience and on this review they give lists of technical benefits and drawbacks of techniques of in vivo dosimetry by EPID transit imagery. They finally indicate some commercially available technical solutions to transit in vivo dosimetry

  5. Quantitative imaging for clinical dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Bardies, Manuel [INSERM U601, 9 Quai Moncousu, 44093 Nantes (France)]. E-mail: manu@nantes.inserm.fr; Flux, Glenn [Department of Physics, Royal Marsden NHS Trust, Sutton (United Kingdom); Lassmann, Michael [Department of Nuclear Medicine, Julis-Maximilians University, Wuerzburg (Germany); Monsieurs, Myriam [Department of Health Physics, University of Ghent, 9000 Ghent (Belgium); Savolainen, Sauli [Department of Physical Sciences, University of Helsinki and HUS, Helsinki Medical Imaging Center, Helsinki University Central Hospital (Finland); Strand, Sven-Erik [Medical Radiation Physics, Department of Clinical Sciences Lund, Lund University (Sweden)

    2006-12-20

    Patient-specific dosimetry in nuclear medicine is now a legal requirement in many countries throughout the EU for targeted radionuclide therapy (TRT) applications. In order to achieve that goal, an increased level of accuracy in dosimetry procedures is needed. Current research in nuclear medicine dosimetry should not only aim at developing new methods to assess the delivered radiation absorbed dose at the patient level, but also to ensure that the proposed methods can be put into practice in a sufficient number of institutions. A unified dosimetry methodology is required for making clinical outcome comparisons possible.

  6. Certification of a niobium metal reference material for neutron dosimetry (EC nuclear reference material 526)

    International Nuclear Information System (INIS)

    Ingelbrecht, C.; Pauwels, J.

    1990-01-01

    Niobium metal, of 99.999% nominal purity, in the form of 0.02 and 0.1 mm thick foil and of 0.5 mm diameter wire, has been certified for its tantalum mass fraction. The certified value of the tantalum mass fraction is 0.3 ± 0.09 mg. Kg -1 , and is based on 70 results obtained by six independent laboratories by neutron activation analysis or inductively coupled plasma mass spectrometry. The material is intended to be used as a reference material in neutron metrology

  7. Iron-based radiochromic systems for UV dosimetry applications

    Science.gov (United States)

    Lee, Hannah J.; Alqathami, Mamdooh; Blencowe, Anton; Ibbott, Geoffrey

    2018-01-01

    Phototherapy treatment using ultraviolet (UV) A and B light sources has long existed as a treatment option for various skin conditions. Quality control for phototherapy treatment recommended by the British Association of Dermatologists and British Photodermatology Group generally focused on instrumentation-based dosimetry measurements. The purpose of this study was to present an alternative, easily prepared dosimeter system for the measurement of UV dose and as a simple quality assurance technique for phototherapy treatments. Five different UVA-sensitive radiochromic dosimeter formulations were investigated and responded with a measurable and visible optical change both in solution and in gel form. Iron(III) reduction reaction formulations were found to be more sensitive to UVA compared to iron(II) oxidation formulations. One iron(III) reduction formulation was found to be especially promising due to its sensitivity to UVA dose, ease of production, and linear response up to a saturation point.

  8. Radiation dosimetry estimates of [{sup 18}F]-fluoroacetate based on biodistribution data of rats

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Jianping [Department of Nuclear Medicine, Fudan University Shanghai Cancer Center, Shanghai 200032 (China); Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032 (China); Zhang Yingjian, E-mail: yjzhang111@yahoo.com.cn [Department of Nuclear Medicine, Fudan University Shanghai Cancer Center, Shanghai 200032 (China); Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032 (China); Xu Junyan; Yang Zhongyi [Department of Nuclear Medicine, Fudan University Shanghai Cancer Center, Shanghai 200032 (China); Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032 (China)

    2012-01-15

    We estimated the dosimetry of [{sup 18}F]fluoroacetate (FAC) with the method established by MIRD based on biodistribution data of rats. We selected some important organs and computed their residence time, their absorbed doses and effective dose with the (%ID{sub Organ}) {sub human} data using OLINDA/EXM 1.1 program. We observed the highest absorbed doses in the heart wall (0.025 mGy/MBq) and the lowest in skin (0.0079 mGy/MBq). The total mean absorbed doses and the effective doses were 0.011 mGy/MBq and 0.014 mSv/MBq, respectively. A 370-MBq injection of FAC leads to an estimated effective dose of 5.2 mSv. The potential radiation risk associated with FAC/PET imaging is well within the accepted limits. - Highlights: Black-Right-Pointing-Pointer We demonstrate a proper model to estimate the absorbed dose and effective dose of normal human. Black-Right-Pointing-Pointer Dosimetry of [{sup 18}F]-Fluoroacetate was estimated in human based on biodistribution of rats. Black-Right-Pointing-Pointer A 370 MBq injection of [{sup 18}F]-Fluoroacetate leads to an estimated effective dose of 5.2 mSv.

  9. Radiotherapy gel dosimetry

    International Nuclear Information System (INIS)

    Baldock, C.

    2002-01-01

    shapes and sizes while sparing normal tissue. The situation is further complicated if the normal tissues are critical organs or are particularly sensitive to radiation. Radiotherapy techniques employed to obtain a closer conformation of the dose distribution to the tumour volume are referred to as conformal radiotherapy techniques. The clinical implementation of conformal therapy has been delayed by limitations in the verification of conformal dose distributions calculated by treatment planning systems prior to the irradiation of the patient and the verification of complex treatments during its delivery to the patient. There are several aspects of conformal therapy that complicate dose verification. To achieve the dose distributions conforming to complex 3D volumes, high dose gradients arise in the treatment volume. Further, overdose or underdose regions can exist when separate radiation fields are used to deliver additional radiation. These aspects require that practical dose measurement (dosimetry) techniques be able to integrate dose over time and easily measure dose distributions in 3D with high spatial resolution. Traditional dosimeters, such as ion chambers, thermoluminescent dosimeters and radiographic film do not fulfil these requirements. Novel gel dosimetry techniques are being developed in which dose distributions can potentially be determined in vitro in 3D using anthropomorphic phantoms to simulate a clinically irradiated situation. As long ago as the 1950's, radiation-induced colour change in dyes was used to investigate radiation doses in gels. It was subsequently shown that radiation induced changes in nuclear magnetic resonance (NMR) relaxation properties of gels infused with conventional Fricke dosimetry solutions could be measured using magnetic resonance imaging (MRI). In Fricke gels, Fe 2+ ions in ferrous sulphate solutions are usually dispersed throughout a gelatin, agarose or PVA matrix. Radiation-induced changes in the dosimeters are considered to

  10. Electron paramagnetic resonance dosimetry using synthetic hydroxyapatite

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Kwon; Kim, Hwi Young; Ye, Sung Joon [Seoul National University, Seoul (Korea, Republic of); Hirata, Hiroshi [Hokkaido University, Sapporo (Japan); Park, Jong Min [Seoul National University Hospital, Seoul (Korea, Republic of)

    2014-11-15

    The victims exposed doses under 3.5-4.0 Gy have chance to survive if treated urgently. To determine the priority of treatment among a large number of victims, the triage – distinguishing patients who need an urgent treatment from who may not be urgent – is necessary based on radiation biodosimetry. A current gold standard for radiation biodosimetry is the chromosomal assay using human lymphocytes. But this method requires too much time and skilled labors to cover the mass victims in radiation emergencies. Electron paramagnetic resonance (EPR) has been known for its capability of quantifying radicals in matters. EPR dosimetry is based on the measurement of stable radiation-induced radicals in tooth enamel. Hydroxyapatite (HAP) (Ca10(PO4)6(OH)2) contained in tooth enamel is a major probe for radiation dose reconstruction. This HAP dosimetry study was performed using a novel EPR spectrometer in Hokkaido University, Japan. The EPR dose-response curve was made using HAP samples. The blind test using 250 cGy samples showed the feasibility of EPR dosimetry for the triage purpose.

  11. SSDL personel dosimetry system: migration from a client - server system into a web-based system

    International Nuclear Information System (INIS)

    Maizura Ibrahim; Rosnah Shariff; Ahmad Bazlie Abdul Kadir; John Konsoh Sangau; Mohd Amin Sharifuldin Salleh; Taiman Kadni; Noriah Mod Ali

    2007-01-01

    Personnel Dosimetry System has been used by the Secondary Standard Dosimetry Laboratory (SSDL), Nuclear Malaysia since ten years ago. The system is a computerized database system with a client-server concept. This system has been used by Film Badge Laboratory, SSDL to record details of clients, calculation of Film Badge dosage, management of radiation workers data's, generating of dosage report, retrieval of statistical reports regarding film badge usage for the purpose of reporting to monitoring bodies such as Atomic Energy Licensing Board (AELB), Ministry of Health and others. But, due to technical problems that frequently occurs, the system is going to be replaced by a newly developed web- based system called e-SSDL. This paper describe the problems that regularly occurs in the previous system, explains how the process of replacing the client-server system with a web-based system is done and the differences between the previous and current system. This paper will also present details architecture of the new system and the new process introduced in processing film badges. (Author)

  12. Thermo-luminescent dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Reither, M; Schorn, B; Schneider, E

    1981-01-01

    The development of paediatric radiology which began in the late 195O's has been characterised by the need to limit the dose of ionising radiation to which the child is subjected. The aim has been to keep radiation exposure as low as possible by the introduction of suitable techniques and by the development of new methods. It is therefore surprising that studies in dosimetry in the paediaytric age range have only been carried out in recent years. One reason for this may have been the fact that a suitable technique of measurement was not available at the time. The introduction of solid state dosimetry based on thermo-luminescence, first into radiotherapy (1968) and subsequently into radiodiagnosis, has made it possible to abandon the previously widely used ionisation chamber. The purpose of the present paper is to indicate the suitability of this form of dose measurement for paediatric radiological purposes and to stimulate its application in this field.

  13. C.T. scan based dosimetry in treating carcinoma of oral tongue

    International Nuclear Information System (INIS)

    Sudarshan, G.; Ranganathan, Vanisehree

    1999-01-01

    It is a well established norm that a combination of external radiation and iridium implant in early stage squamous cell carcinoma (SCC) of oral tongue gives good results. We have treated 10 consecutive patients of SCC of anterior 2/3 of tongue staged T1-2 NO by giving 4000 cGy external radiation and 3000 cGy boost with iridium-192 implant. Traditionally, orthogonal radiographs have been taken to determine the spatial distribution of sources. As we do not have a simulator, we have taken 2-4 C.T. scan images perpendicular to the axis of implant. By using this cross-sectional information, we identified the source points and a basal dose rate was calculated manually by following the geometric principles of Paris system as our T.P.S. did not have the required software. Clinically, 9 out of the 10 patients are in remission (N.E.D. = No evidence of disease) at 18 months follow-up. Our aim of this presentation is to compare manual dosimetry with T.P.S. generated dosimetry and to show that manual dosimetry is also dependable. (author)

  14. OSL Based Anthropomorphic Phantom and Real-Time Organ Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    David E. Hintenlang, Ph.D

    2009-02-10

    The overall objective of this project was the development of a dosimetry system that provides the direct measurement of organ does in real-time with a sensitivity that makes it an effective tool for applications in a wide variety of health physics applications. The system included the development of a real-time readout system for fiber optic coupled (FOC) dosimeters that is integrated with a state-of-art anthropomorphic phantom to provide instantaneous measures of organ doses throughout the phantom. The small size of the FOC detectors and optical fibers allow the sensitive volume of the detector to be located at organ centroids (or multiple locations distributed through the organ) within a tissue equivalent, anthropomorphic phantom without perturbing the tissue equivalent features of the phantom. The developed phantom/dosimetry system can be used in any environment where personnel may be exposed to gamma or x-ray radiations to provide the most accurate determinations of organ and effective doses possible to date.

  15. OSL Based Anthropomorphic Phantom and Real-Time Organ Dosimetry

    International Nuclear Information System (INIS)

    Hintenlang, David E.

    2009-01-01

    The overall objective of this project was the development of a dosimetry system that provides the direct measurement of organ doses in real-time with a sensitivity that makes it an effective tool for applications in a wide variety of health physics applications. The system included the development of a real-time readout system for fiber optic coupled (FOC) dosimeters that is integrated with a state-of-art anthropomorphic phantom to provide instantaneous measures of organ doses throughout the phantom. The small size of the FOC detectors and optical fibers allow the sensitive volume of the detector to be located at organ centroids (or multiple locations distributed through the organ) within a tissue equivalent, anthropomorphic phantom without perturbing the tissue equivalent features of the phantom. The developed phantom/dosimetry system can be used in any environment where personnel may be exposed to gamma or x-ray radiations to provide the most accurate determinations of organ and effective doses possible to date

  16. Radiation Dosimetry of a Novel Adenosine A(2A) Receptor Radioligand [C-11]Preladenant Based on PET/CT Imaging and Ex Vivo Biodistribution in Rats

    NARCIS (Netherlands)

    Zhou, Xiaoyun; Elsinga, Philip H.; Khanapur, Shivashankar; Dierckx, Rudi A. J. O.; de Vries, Erik F. J.; de Jong, Johan R.

    [C-11]Preladenant was developed as a novel adenosine A(2A) receptor PET radioligand. The aim of this study was to determine the radiation dosimetry of [C-11]preladenant and to investigate whether dosimetry estimation based on organ harvesting can be replaced by positron emission tomography

  17. Alanine EPR dosimetry of therapeutic irradiators

    International Nuclear Information System (INIS)

    Bugay, O.; Bartchuk, V.; Kolesnik, S.; Mazin, M.; Gaponenko, H.

    1999-01-01

    The high-dose alanine EPR dosimetry is a very precise method in the dose range 1-100 kGy. The system is used generally as the standard high-dose transfer dosimetry in many laboratories. This is comparatively expensive technique so it is important to use it as a more universal dosimetry system also in the middle and low dose ranges. The problems of the middle-dose alanine dosimetry are discussed and the solution of several problems is proposed. The alanine EPR dosimetry has been applied to the dose measurements of medical irradiators in the Kiev City Oncology Center. (author)

  18. Radiation Protection and Dosimetry An Introduction to Health Physics

    CERN Document Server

    Stabin, Michael G

    2007-01-01

    This comprehensive text provides an overview of all relevant topics in the field of radiation protection (health physics). Radiation Protection and Dosimetry serves as an essential handbook for practicing health physics professionals, and is also ideal as a teaching text for courses at the university level. The book is organized to introduce the reader to basic principles of radiation decay and interactions, to review current knowledge and historical aspects of the biological effects of radiation, and to cover important operational topics such as radiation shielding and dosimetry. In addition to presenting the most up to date treatment of the topics and references to the literature, most chapters contain numerical problems with their solutions for use in teaching or self assessment. One chapter is devoted to Environmental Health Physics, which was written in collaboration with leading professionals in the area.

  19. EURADOS strategic research agenda: vision for dosimetry of ionising radiation

    International Nuclear Information System (INIS)

    Ruehm, W.; Woda, C.; Fantuzzi, E.; Harrison, R.; Schuhmacher, H.; Neumaier, S.; Vanhavere, F.; Alves, J.; Bottollier Depois, J.F.; Fattibene, P.; Knezevic, Z.; Miljanic, S.; Lopez, M. A.; Mayer, S.; Olko, P.; Stadtmann, H.; Tanner, R.

    2016-01-01

    Since autumn 2012, the European Radiation Dosimetry Group (EURADOS) has been developing its Strategic Research Agenda (SRA), which is intended to contribute to the identification of future research needs in radiation dosimetry in Europe. The present article summarises-based on input from EURADOS Working Groups (WGs) and Voting Members-five visions in dosimetry and defines key issues in dosimetry research that are considered important for the next decades. The five visions include scientific developments required towards (a) updated fundamental dose concepts and quantities, (b) improved radiation risk estimates deduced from epidemiological cohorts, (c) efficient dose assessment for radiological emergencies, (d) integrated personalised dosimetry in medical applications and (e) improved radiation protection of workers and the public. The SRA of EURADOS will be used as a guideline for future activities of the EURADOS WGs. A detailed version of the SRA can be downloaded as a EURADOS report from the EURADOS web site (www.eurados.org). (authors)

  20. Certification of a nickel metal reference material for neutron dosimetry (EC Nuclear Reference Material 521)

    International Nuclear Information System (INIS)

    Pauwels, J.

    1988-01-01

    Nickel metal, of 99.99 % nominal purity and natural isotopic composition, in the form of 0.1 mm thick foil and 0.5 mm diameter wire has been certified for its cobalt mass fraction. The certified value of cobalt (<0.1μg.g-1) is based on 38 results obtained by neutron activation analysis, emission spectrometry with inductively coupled plasma excitation and atomic absorption spectrometry, whereas the isotopic composition of the nickel was verified by thermal ionization mass spectrometry. The material is intended to be used as a reference material in neutron metrology

  1. Certification of an aluminium metal reference material for neutron dosimetry (EC nuclear reference material 523)

    International Nuclear Information System (INIS)

    Pauwels, J.; Ingelbrecht, C.

    1990-01-01

    Aluminium metal of > 99.999% nominal purity in the form of 0.1 mm and 1 mm thick foil and of 1 mm diameter wire has been certified for its sodium mass fraction. The certified value of the sodium mass fraction ( -1 ) is based on 21 results from three laboratories using two different methods, which are neutron activation analysis and atomic absorption spectrometry. The overall purity was estimated using spark source mass spectrometry and neutron activation analysis. The material is intended to be used as a reference material in neutron metrology

  2. Proposals for common definitions of reference points in gynecological brachytherapy

    International Nuclear Information System (INIS)

    Chassagne, D.; Horiot, J.C.

    1977-01-01

    In May 1975 the report of European Curietherapy Group recommended in gynecological Dosimetry by computer. Use of reference points = lymphatic trapezoid figure with 6 points, Pelvic wall, all points are refering to bony structures. Use of critical organ reference points = maximum rectum dose, bladder dose mean rectal dose. Use of 6,000 rads reference isodose described by height, width, and thickness dimensions. These proposals are the basis of a common language in gynecological brachytherapy [fr

  3. Dosimetry study comparing NCS report-2 versus IAEA TRS-398 protocol for high energy photon beams

    International Nuclear Information System (INIS)

    Attalaa, E.M.; Khaled, N.E.; Abou Elenein, H.S.; Elsayed, A.A.

    2005-01-01

    In this work a dosimetry study is presented in which the results of absorbed dose determined at reference condition according to the IAEA TRS-398 protocol and the NCS report-2 are compared. The IAEA TRS-398 protocol for absorbed dose calibration is based on ionization chamber having absorbed dose to water calibration factor N d w, while the NCS-2 dosimetry report for absorbed dose calibration is based on an ionization chamber having air- kerma calibration factor N k . This study shows that the absorbed dose which is calculated with The IAEA TRS-398 formalisms is higher than that calculated with NCS report-2 formalisms within range from 0.4 to 0.9% in cobalt-60 beam as sensed by different ionization chambers, and from 0.2 to 1.1% for different higher energy photon beams of 6, 8 and 18 MV. The chambers used are PTW 30001, 30004, and NE-2571; which have calibration factors N k and N d w traceable to the BIPM (Bureau International des Poids et Mesures)

  4. Biological dosimetry study in differentiated thyroid carcinoma patients treated with 131Iodine

    International Nuclear Information System (INIS)

    Vallerga, Maria Belen

    2008-11-01

    Biological Dosimetry allows individual dose assessments based on the effect produced by ionizing radiation on a given biological parameter. The current biological endpoint being scored is chromosomal aberrations, relying on a lymphocytes culture from the patient's blood. The measured yield of chromosome aberrations is referred to a calibration curve obtaining the whole body dose. Different scenarios of overexposure can be taken into account by modifying the calculations leading to the dose estimate. Differentiated Thyroid Carcinoma patients undergo thyroidectomy followed by internal radiotherapy with 131 I. The treatment's success entails the delivery of a lethal dose to the tumour within the maximum tolerable dose to a critical organ (blood doses over 2 Gy could lead to bone marrow depression). Currently, there is no established agreement for the selection of radioiodine dosage. Historically, the empiric approach, based on clinical and biochemical data, has been recommended. Nevertheless, this method may not be associated with optimal outcomes. On the other hand, the dosimetric approach attempts to determine the maximum allowable activity to be administered, establishing its biokinetics by a diagnostic 131 I study. The methodology may be modified to further individualized treatment, however it requires validation. Biological dosimetry provides an independent measure of radiotherapy effect, as such it might aid in the validation process. Nonetheless, biological dosimetry has traditionally been applied in cases of external and accidental overexposure to ionizing radiation. Accordingly, it is mandatory to assess its value in medical internal incorporations (main objective of the present study). The applied treatment strategy comprises whole body dose assessment by biological and internal dosimetry in order to administer a personalized therapeutic activity. Overall, 20 patients with differentiated thyroid carcinoma were included in the study. For biological dosimetry

  5. Radiochromic film dosimetry

    International Nuclear Information System (INIS)

    Xu Zhiyong

    2002-01-01

    Radiochromic film dosimetry was developed to measure ionization irradiation dose for industry and medicine. At this time, there are no comprehensive guideline on the medical application, calibration method and densitometer system for medicine. The review gives update on Radiochromic film dosimetry used for medicine, including principles, film model and material, characteristics, calibration method, scanning densitometer system and medical application

  6. 11. International conference on solid radiation dosimetry

    International Nuclear Information System (INIS)

    Krylova, I.V.

    1996-01-01

    The main problems discussed during the international conference on solid radiation dosimetry which took place in June 1995 in Budapest are briefly considered. These are the basic physical processes, materials applied for dosimetry, special techniques, personnel monitoring, monitoring of environmental effects, large-dose dosimetry, clinic dosimetry, track detector used for dosimetry, dosimetry in archaeology and geology, equipment and technique for dosimetric measurements. The special attention was paid to superlinearity in the TLD-100 (LiF, Mg, Ti) response function when determining doses of gamma radiation, heavy charged particles, low-energy particle fluxes in particular. New theoretical models were considered

  7. The UK radiotherapy dosimetry audit network

    International Nuclear Information System (INIS)

    Thwaites, D.I.

    2002-01-01

    Full text: Radiotherapy dosimetry intercomparison in the UK has been carried out in limited studies since the 1960s. However the first national dosimetry intercomparison involving all radiotherapy centres was conducted in the late 1980s. This was based on visits to each centre, using ionisation chamber dosimetry. It audited megavoltage photon beam calibration and other single field parameters. It also measured doses in a three-field 'treatment' in a trapezoidal phantom constructed from epoxy-resin water-equivalent material and compared these to locally planned doses. This included off-axis points, oblique incidence, inhomogeneities, etc. The study found mean measured beam calibration doses close to stated values (ratio 1.003), with a standard deviation (sd) of the distribution of 1.5% and 97% of doses within the pro-set 3% tolerance. For the planned multi-field irradiations, mean dose ratios (measured/stated) were 1.01 (sd 3%, 90% of results within 5%). A number of discrepancies were identified, leading to improved practice. A follow up study (mid-1990s) for electron beam audit also repeated the megavoltage photon calibration audit. For photons, an improvement was noted (mean ratio 1.003, sd 1.0%, 100% within 3%), whilst for electron beams, the mean ratio of measured/stated dose was 0.994 (sd 1.8%, 94% within 3%, 99% within 5%). In parallel with - and growing out of - this, a national audit network began to develop in 1991/2. It utilised similar methodology to the intercomparison and a network approach to allow parallel developments of the scope of the system. The network has eight regional groups, each with up to 10 radiotherapy centres, serving average populations of 7-8 million. Each group organises audits of its own centres and has developed at its own pace. Most have piloted methodology, phantoms, etc. for new audits which can then be used by other groups. All 65 UK centres are included. The network is co-ordinated by an IPEM Steering Committee (current chair

  8. Studies in dosimetry using stimulated exoelectron emission

    International Nuclear Information System (INIS)

    Petel, Maurice.

    1976-06-01

    Some applications of the stimulated exoelectron emission in radiation dosimetry are discussed. The principles which govern the phenomenon are presented. The apparatus, in particular the counter, used to monitor the emission is discussed with reference to both optical and thermal stimulation. The correlation existing between thermoluminescence and thermally stimulated exoelectron emission were studied in both lithium fluoride and aluminium oxide. Furthermore, aluminium oxides from different sources were examined, and one of these, chosen to investigate the dosimetric properties of this material using both methods of stimulation [fr

  9. A microcomputer controlled thermoluminescence dosimetry system

    International Nuclear Information System (INIS)

    Huyskens, C.J.; Kicken, P.J.H.

    1980-01-01

    Using a microcomputer, an automatic thermoluminescence dosimetry system for personal dosimetry and thermoluminescence detector (TLD) research was developed. Process automation, statistical computation and dose calculation are provided by this microcomputer. Recording of measurement data, as well as dose record keeping for radiological workers is carried out with floppy disk. The microcomputer also provides a human/system interface by means of a video display and a printer. The main features of this dosimetry system are its low cost, high degree of flexibility, high degree of automation and the feasibility for use in routine dosimetry as well as in TLD research. The system is in use for personal dosimetry, environmental dosimetry and for TL-research work. Because of its modular set-up several components of the system are in use for other applications, too. The system seems suited for medium sized health physics groups. (author)

  10. An image-based skeletal tissue model for the ICRP reference newborn

    Energy Technology Data Exchange (ETDEWEB)

    Pafundi, Deanna; Lee, Choonsik; Bolch, Wesley [Department of Nuclear and Radiological Engineering, University of Florida, Gainesville, FL (United States); Watchman, Christopher; Bourke, Vincent [Department of Radiation Oncology, University of Arizona, Tucson, AZ (United States); Aris, John [Department of Anatomy and Cell Biology, University of Florida, Gainesville, FL (United States); Shagina, Natalia [Urals Research Center for Radiation Medicine, Chelyabinsk (Russian Federation); Harrison, John; Fell, Tim [Radiation Protection Division, Health Protection Agency, Chilton (United Kingdom)], E-mail: wbolch@ufl.edu

    2009-07-21

    Hybrid phantoms represent a third generation of computational models of human anatomy needed for dose assessment in both external and internal radiation exposures. Recently, we presented the first whole-body hybrid phantom of the ICRP reference newborn with a skeleton constructed from both non-uniform rational B-spline and polygon-mesh surfaces (Lee et al 2007 Phys. Med. Biol. 52 3309-33). The skeleton in that model included regions of cartilage and fibrous connective tissue, with the remainder given as a homogenous mixture of cortical and trabecular bone, active marrow and miscellaneous skeletal tissues. In the present study, we present a comprehensive skeletal tissue model of the ICRP reference newborn to permit a heterogeneous representation of the skeleton in that hybrid phantom set-both male and female-that explicitly includes a delineation of cortical bone so that marrow shielding effects are correctly modeled for low-energy photons incident upon the newborn skeleton. Data sources for the tissue model were threefold. First, skeletal site-dependent volumes of homogeneous bone were obtained from whole-cadaver CT image analyses. Second, selected newborn bone specimens were acquired at autopsy and subjected to micro-CT image analysis to derive model parameters of the marrow cavity and bone trabecular 3D microarchitecture. Third, data given in ICRP Publications 70 and 89 were selected to match reference values on total skeletal tissue mass. Active marrow distributions were found to be in reasonable agreement with those given previously by the ICRP. However, significant differences were seen in total skeletal and site-specific masses of trabecular and cortical bone between the current and ICRP newborn skeletal tissue models. The latter utilizes an age-independent ratio of 80%/20% cortical and trabecular bone for the reference newborn. In the current study, a ratio closer to 40%/60% is used based upon newborn CT and micro-CT skeletal image analyses. These changes in

  11. Characterising an aluminium oxide dosimetry system.

    Science.gov (United States)

    Conheady, Clement F; Gagliardi, Frank M; Ackerly, Trevor

    2015-09-01

    In vivo dosimetry is recommended as a defence-in-depth strategy in radiotherapy treatments and is currently employed by clinics around the world. The characteristics of a new optically stimulated luminescence dosimetry system were investigated for the purpose of replacing an aging thermoluminescence dosimetry system for in vivo dosimetry. The stability of the system was not sufficient to satisfy commissioning requirements and therefore it has not been released into clinical service at this time.

  12. Comparison of Different Internal Dosimetry Systems for Selected Radionuclides Important to Nuclear Power Production

    Energy Technology Data Exchange (ETDEWEB)

    Leggett, Richard Wayne [ORNL; Eckerman, Keith F [ORNL; Manger, Ryan P [ORNL

    2013-08-01

    This report compares three different radiation dosimetry systems currently applied by various U.S. Federal agencies and dose estimates based on these three dosimetry systems for a set of radionuclides often identified in power reactor effluents. These dosimetry systems were developed and applied by the International Commission on Radiological Protection at different times over the past six decades. Two primary modes of intake of radionuclides are addressed: ingestion in drinking water and inhalation. Estimated doses to individual organs and to the whole body based on each dosimetry system are compared for each of four age groups: infant, child, teenager, and adult. Substantial differences between dosimetry systems in estimated dose per unit intake are found for some individual radionuclides, but differences in estimated dose per unit intake generally are modest for mixtures of radionuclides typically found in nuclear power plant effluents.

  13. Quality audit service of the IAEA for radiation processing dosimetry

    International Nuclear Information System (INIS)

    Mehta, K.; Girzikowsky, R.

    1996-01-01

    The mandate of the International Atomic Energy Agency includes assistance to Member States to establish nuclear technologies safely and effectively. In pursuit of this, a quality audit service for dosimetry relevant to radiation processing was initiated as a key element of the High-Dose Standardization Programme of the IAEA. The standardization of dosimetry for radiation processing provides a justification for the regulatory approval of irradiated products and their unrestricted international trade. In recent times, the Agency's Dosimetry Laboratory has placed concentrated effort towards establishing a quality assurance programme based on the ISO 9000 series documents. The need for reliable and accurate dosimetry for radiation processing is increasing in Member States and we can envisage a definite role for the SSDLs in such a programme. (author). 10 refs, 3 figs

  14. Implantation of radiodiagnostic reference radiations at the CDTN/CNEN for dosemeter calibration

    International Nuclear Information System (INIS)

    Baptista Neto, A.T.; Oliveira, P.M.C. de; Ferreira, F.C.B.

    2009-01-01

    A reliable dosimetry in diagnostic radiology is based on the traceability of calibrated and type-tested dosimeters in reference radiations that were established by the International Electrotechnical Commission (IEC). Metrology laboratories are expected to implement the reference radiations by reproducing the x-ray beam parameters within standard limits. This work shows the results of the implementation in the CDTN/CNEN-MG of the reference radiations for diagnostic radiology. The half value-layers and the homogeneity coefficients were determined for the primary (RQR), attenuated (RQA) and computerized tomography (RQT) x-ray beams. Results complied with the IEC limits which it means that the CDTN and the IEC reference radiations are similar and they can be used for calibration and type-testing of dosimeters to be used in diagnostic radiology. (author)

  15. Neutron Reference Benchmark Field Specification: ACRR 44 Inch Lead-Boron (LB44) Bucket Environment (ACRR-LB44-CC-32-CL).

    Energy Technology Data Exchange (ETDEWEB)

    Vega, Richard Manuel [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Parma, Edward J. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Griffin, Patrick J. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Vehar, David W. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)

    2015-07-01

    This report was put together to support the International Atomic Energy Agency (IAEA) REAL- 2016 activity to validate the dosimetry community’s ability to use a consistent set of activation data and to derive consistent spectral characterizations. The report captures details of integral measurements taken in the Annular Core Research Reactor (ACRR) central cavity with the 44 inch Lead-Boron (LB44) bucket, reference neutron benchmark field. The field is described and an “a priori” calculated neutron spectrum is reported, based on MCNP6 calculations, and a subject matter expert (SME) based covariance matrix is given for this “a priori” spectrum. The results of 31 integral dosimetry measurements in the neutron field are reported.

  16. Thermoluminescent dosemeters characterization for patient dosimetry in diagnostic radiology preliminary results

    International Nuclear Information System (INIS)

    Castro, William J.; Squair, Peterson L.; Gonzaga, Natalia B.; Nogueira, Maria S.; Silva, Teogenes A. da

    2009-01-01

    The determination of the metrological characteristics of thermoluminescent (TL) dosimeters plays an important role in dosimetry of patients submitted to x-ray examinations for diagnostic purpose. Entrance surface doses can be measured with TL dosimeters to verify the compliance with the diagnostic reference levels. Organ doses can be estimated through TL measurements in an anthropomorphic phantom which it allows the radiation risk assessment. In this work, LiF:Mg,Ti (TLD-100) rod and chip thermoluminescent dosimeters were characterized considering their use for patient dosimetry in computerized tomography and mammography. Preliminary results showed that TL dosimeters have a response reproducibility of 7.8% and 4.8% and homogeneity of 18.4% and 6.5% for rod and chip shapes, respectively. (author)

  17. Instrumentation in thermoluminescence dosimetry

    International Nuclear Information System (INIS)

    Julius, H.W.

    1986-01-01

    In the performance of a thermoluminescence dosimetry (TLD) system the equipment plays an important role. Crucial parameters of instrumentation in TLD are discussed in some detail. A review is given of equipment available on the market today - with some emphasis on automation - which is partly based on information from industry and others involved in research and development. (author)

  18. The dosimetry of ionizing radiation

    CERN Document Server

    1990-01-01

    A continuation of the treatise The Dosimetry of Ionizing Radiation, Volume III builds upon the foundations of Volumes I and II and the tradition of the preceeding treatise Radiation Dosimetry. Volume III contains three comprehensive chapters on the applications of radiation dosimetry in particular research and medical settings, a chapter on unique and useful detectors, and two chapters on Monte Carlo techniques and their applications.

  19. Dosimetry applied to radiology and radiotherapy

    International Nuclear Information System (INIS)

    Yoshimura, Elisabeth Mateus

    2010-01-01

    Full text. The uses of ionizing radiation in medicine are increasing worldwide, and the population doses increase as well. The actual radiation protection philosophy is based on the balance of risks and benefits related to the practices, and patient dosimetry has an important role in the implementation of this point of view. In radiology the goal is to obtain an image with diagnostic quality with the minimum patient dose. In modern Radiotherapy the cure indexes are higher, giving rise to longer survival times to the patients. Dosimetry in radiotherapy helps the treatment planning systems to get a better protection to critical organs, with higher doses to the tumor, with a guarantee of better life quality to the patient. We will talk about the new trends in dosimetry of medical procedures, including experimental techniques and calculation tools developed to increase reliability and precision of dose determination. In radiology the main concerns of dosimetry are: the transition from film- radiography to digital image, the pediatric patient doses, and the choice of dosimetric quantities to quantify fluoroscopy and tomography patient doses. As far as Radiotherapy is concerned, there is a search for good experimental techniques to quantify doses to tissues adjacent to the target volumes in patients treated with new radiotherapy techniques, as IMRT and heavy particle therapy. (author)

  20. Dose measurements in dental radiology using thermoluminescent dosimetry;Medicoes de dose em radiodiagnostico odontologico utilizando dosimetria termoluminescente

    Energy Technology Data Exchange (ETDEWEB)

    Chiara, Ana Claudia M. de; Costa, Alessandro M. [Universidade de Sao Paulo (FFCLRP/USP), Ribeirao Preto, SP (Brazil). Faculdade de Filosofia, Ciencias e Letras; Pardini, Luiz Carlos [Universidade de Sao Paulo (FORP/USP), Ribeirao Preto, SP (Brazil). Faculdade de Odontologia

    2009-07-01

    The aim of this work was the implementation of a code of practice for dosimetry in dental radiology using the technique of thermoluminescent dosimetry. General principles for the use of thermoluminescent dosimeters were followed. The irradiations were performed using ten X-ray equipment for intra-oral radiography and an X-ray equipment for panoramic radiography. The incident air kerma was evaluated for five different exposure times used in clinical practice for intra-oral radiographs. Using a backscatter factor of 1.2, it was observed that approximately 40% of the entrance skin dose values found for intra-oral radiographs are above the diagnostic reference level recommended in national regulation. Different configurations of voltage and current were used representing the exposure as a child, woman and man for panoramic radiographs. The results obtained for the air kerma area product were respectively 53.3 +- 5.2 mGy.cm{sup 2}, 101.5 +- 9.5 mGy.cm{sup 2} and 116.8 +- 10.4 mGy.cm{sup 2}. The use of thermoluminescent dosimetry requires several procedures before a result is recorded. The use of dosimeters with ionization chambers or semiconductors provides a simple and robust method for routine measurements. However, the use of thermoluminescent dosimetry can be of great value to large-scale surveys to establish diagnostic reference levels. (author)

  1. A portable organic plastic scintillator dosimetry system for low energy X-rays: a feasibility study using an intraoperative X-ray unit as the radiation source

    International Nuclear Information System (INIS)

    Williams, Kerry; Robinson, Neil; Trapp, Jamie; Geso, Moshi; Ackerly, Trevor; Das, Ram; Kemp, Penny

    2007-01-01

    The effective use of near water equivalent organic plastic scintillators (OPS) for radiation dosimetry with high-energy sources under laboratory conditions is recognized. In this work, an OPS-based dosimeter using a photodiode combined with improved solid state detection and signal processing techniques has been developed; it offers the potential for the construction of a stable and fully portable dosimeter which will extend the useful range of measurement beyond the usual MeV area and provide reliable readings down to sub-100 keV X-ray energy levels. In these experiments, the instrument described has been used for the dosimetry of INTRABEAM intraoperative radiotherapy (IORT) equipment at distances as low as 1.8 mm from the effective source, i.e., 0.2 mm from the X-ray probe surface. Comparison is shown with dosimetry measurements made using the calibrated reference ion chamber supplied by the IORT equipment manufacturer. (author)

  2. Performance testing of UK personal dosimetry laboratories

    CERN Document Server

    Marshall, T O

    1985-01-01

    The proposed Ionising Radiations Regulations will require all UK personal dosimetry laboratories that monitor classified personnel to be approved for personal dosimetry by the Health and Safety Executive. It is suggested that these approvals should be based on general and supplementary criteria published by the British Calibration Service (BCS) for laboratory approval for the provision of personal dosimetry services. These criteria specify certain qualitative requirements and also indicate the need for regular tests of performance to be carried out to ensure constancy of dosimetric standards. This report concerns the latter. The status of the BCS criteria is discussed and the need for additional documents to cover new techniques and some modifications to existing documents is indicated. A means is described by which the technical performance of laboratories, concerned with personal monitoring for external radiations, can be assessed, both initially and ongoing. The costs to establish the scheme and operate it...

  3. Integration of external and internal dosimetry in Switzerland

    International Nuclear Information System (INIS)

    Frei, D.; Wernli, C.; Baechler, S.; Fischer, G.; Jossen, H.; Leupin, A.; Lortscher, Y.; Mini, R.; Otto, T.; Schuh, R.; Weidmann, U.

    2007-01-01

    Individual monitoring regulations in Switzerland are based on the ICRP60 recommendations. The annual limit of 20 mSv for the effective dose applies to the sum of external and internal radiation. External radiation is monitored monthly or quarterly with TLD, DIS or CR-39 dosemeters by 10 approved external dosimetry services and reported as H p (10) and H p (0.07). Internal monitoring is done in two steps. At the workplace, simple screening measurements are done frequently in order to recognise a possible incorporation. If a nuclide dependent activity threshold is exceeded then one of the seven approved dosimetry services for internal radiation does an incorporation measurement to assess the committed effective dose E 50 . The dosimetry services report all the measured or assessed dose values to the employer and to the National Dose Registry. The employer records the annually accumulated dose values into the individual dose certificate of the occupationally exposed person, both the external dose H p (10) and the internal dose E 50 as well as the total effective dose E = H p (10) + E 50 . Based on the national dose registry an annual report on the dosimetry in Switzerland is published which contains the statistics for the total effective dose, as well as separate statistics for external and internal exposure. (authors)

  4. Practice for use of a dichromate dosimetry system

    International Nuclear Information System (INIS)

    2003-01-01

    This practice covers the preparation, testing, and procedure for using the acidic aqueous silver dichromate dosimetry system to measure absorbed dose in water when exposed to ionizing radiation. The system consists of a dosimeter and appropriate analytical instrumentation. For simplicity, the system will be referred to as the dichromate system. It is classified as a reference standard dosimetry system (see ISO/ASTM Guide 51261). This practice describes the spectrophotometric analysis procedures for the dichromate system. This practice applies only to γ-rays, x-rays/ bremsstrahlung, and high energy electrons. This practice applies provided the following conditions are satisfied: the absorbed dose range is from 2x10 3 to 5x10 4 Gy; the absorbed dose rate does not exceed 600 Gy/pulse (12.5 pulses per second), or does not exceed an equivalent dose rate of 7.5 kGy/s from continuous sources; for radionuclide gamma-ray sources, the initial photon energy shall be greater than 0.6 MeV. For bremsstrahlung photons, the initial energy of the electrons used to produce the bremsstrahlung photons shall be equal to or greater than 2 MeV. For electron beams, the initial electron energy shall be greater than 8 MeV; the irradiation temperature of the dosimeter shall be above 0 deg C and should be below 80 deg C

  5. Clinical electron beam dosimetry: transition from AAPM TG-25 to AAPM TG-70

    International Nuclear Information System (INIS)

    Mihailidis, Dimitris

    2017-01-01

    The absolute calibration of clinical electron beams is increasingly based on TG-51 protocol. In addition, recently published dosimetry data on electrons beams bring up the question of how would one need to modify the widely used TG-25 that originally was based on TG-21 calibration protocol? The answer to the question is given by the recently published TG-70. This new protocol operates as supplement and update to TG-25 on issues that need to be modified because of TG-51 approach to electron dosimetry and because of newer data on clinical electron beams. It describes in detail the procedure of converting measured depth-ionization curves with ion chambers into depth-dose curves, making use of recently published stopping-power ratios and other conversion factors. It also describes the use of water equivalent phantoms to perform relative electron dosimetry based on recently published conversions factors. The report discusses small and irregularly shaped electron field dosimetry using the concept of lateral buildup ratio (LBR) as an avenue to evaluate electronic equilibrium and compute dose per MU for those fields. Finally, it gives some common clinical examples where electron beam dosimetry are applied

  6. Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Hurst, G S; Ritchie, R H; Sanders, F W; Reinhardt, P W; Auxier, J A; Wagner, E B; Callihan, A D; Morgan, K Z [Health Physics Division, Oak Ridge National Laboratory, Oak Ridge, TN (United States)

    1962-03-01

    The methods of dosimetry used for investigation of the doses received by the individuals exposed in the Yugoslav accident were essentially those used in connection with the Oak Ridge Y-12 accident. An outline of the general scheme is as follows: When fast neutrons enter the human body, most of these are moderated to thermal energy and a small fraction of these are captured by a (n, {gamma}) process in Na{sup 23}, giving rise to Na{sup 24}, which by virtue of its emission of high-energy gamma rays with a half life of 14.8 h, is easily detected. It has been shown that the probability of capture, making Na{sup 24}, is not a strong function of the energy of the fast neutrons and that the probability of capture for neutrons is higher in the fast region than in the thermal region. Thus, the uniform distribution of Na{sup 23} in the human body provides an excellent means of normalizing the neutron exposure of an individual. in particular, for a given neutron energy spectrum the fast neutron dose is proportional to the ratio Na{sup 24}/Na{sup 23} in the body or in the blood system. This method of normalization is quite important in the dosimetry of radiation accidents since no assumptions need be made about the exact location of an individual at the time of the energy release. The importance of this fact can be made clear by reference to the Y-12 accident where it was shown by calculation of the neutron dose based on the known number of fissions and the stated location of the individual that one of the surviving individuals would have received a dose several times the lethal value. To accomplish the measurements described, the zero power R{sub B} reactor was operated in two ranges of power level, 'low' power and 'high 'power. Neutron leakage spectrum was obtained by multigroup approximation of the Boltzman transport equation. Prompt gamma rays from fission products, from capture in the moderator and fuel cladding as well as in tank walls are given. A summary of the 4{pi

  7. Neutron dosimetry at a high-energy electron-positron collider

    Science.gov (United States)

    Bedogni, Roberto

    Electron-positron colliders with energy of hundreds of MeV per beam have been employed for studies in the domain of nuclear and sub-nuclear physics. The typical structure of such a collider includes an LINAC, able to produce both types of particles, an accumulator ring and a main ring, whose diameter ranges from several tens to hundred meters and allows circulating particle currents of several amperes per beam. As a consequence of the interaction of the primary particles with targets, shutters, structures and barriers, a complex radiation environment is produced. This paper addresses the neutron dosimetry issues associated with the operation of such accelerators, referring in particular to the DAΦ NE complex, operative since 1997 at INFN-Frascati National Laboratory (Italy). Special attention is given to the active and passive techniques used for the spectrometric and dosimetric characterization of the workplace neutron fields, for radiation protection dosimetry purposes.

  8. New web interface for Personal dosimetry VF, a.s

    International Nuclear Information System (INIS)

    Studeny, J.

    2014-01-01

    The lecture will introduce new functions and graphic design WebSOD - web interface Personal dosimetry Service VF. a.s. which will be updated in November 2014. The new interface will have a new graphic design, intuitive control system and will be providing a range of new functions: - Personal doses - display of personal doses from personal, extremity and neutron dosimeters including graphs, annual and electronic listings of doses; - Collective doses - display of group doses for selected periods of time; Reference levels - setting and display of three reference levels; - Evidence - enables administration of monitored individuals - beginning, ending of monitoring, or editing the data of monitored persons and centers. (author)

  9. Modern methods of personnel dosimetry

    International Nuclear Information System (INIS)

    Kraus, W.; Herrmann, D.; Kiesewetter, W.

    The physical properties of radiation detectors for personnel dosimetry are described and compared. The suitability of different types of dosimeters for operational and central monitoring of normal occupational exposure, for accident and catastrophe dosimetry and for background and space-flight dosimetry is discussed. The difficulties in interpreting the dosimeter reading with respect to the dose in individual body organs are discussed briefly. 430 literature citations (up to Spring 1966) are given

  10. Cytogenetic Dosimetry: Applications in Preparedness for and Response to Radiation Emergencies - Training Materials

    International Nuclear Information System (INIS)

    2013-01-01

    These materials are designed for use at a four day training course on the application of cytogenetic dosimetry in preparedness for and response to radiation emergencies. They contain information on: (1) Basics of biological effects of ionizing radiation: Parts 1+2; (2) Basics of dosimetry; (3) dicentric assay; (4) Retrospective dosimetry by translocation analysis; (5) Premature chromosome condensation analysis; (6) Cytokinesis block micronucleus assay; (7) Applied statistics for biodosimetry; (8) Automatic analysis of chromosomal assays; (9) Biodosimetry in mass casualty events; (10) Safety of laboratory staff and quality programmes; (11) Examples of accident investigations; (12) Cytogenetic dose estimation in the criticality accident in Tokaimura; (13) Radiological accidents in Latin America; (14) Radiological accidents in Georgia. Additionally, the CD contains two working sessions with the reference materials for use and a standard training programme. This training course consists of lectures and work sessions that can easily be utilized by a State to build a basic capability in biodosimetry application in a nuclear or radiological emergency

  11. International Intercomparison Exercise for Nuclear Accident Dosimetry at the DAF Using GODIVA-IV

    Energy Technology Data Exchange (ETDEWEB)

    Hickman, David [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Hudson, Becka [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-12-15

    The Nuclear Criticality Safety Program operated under the direction of Dr. Jerry McKamy completed the first NNSA Nuclear Accident Dosimetry exercise on May 27, 2016. Participants in the exercise were from Lawrence Livermore National Laboratory (LLNL), Los Alamos National Laboratory (LANL), Sandia National Laboratory (SNL), Savanah River Site (SRS), Pacific Northwest National Laboratory (PNNL), US Navy, the Atomic Weapons Establishment (United Kingdom) under the auspices of JOWOG 30, and the Institute for Radiological Protection and Nuclear Safety (France) by special invitation and NCSP memorandum of understanding. This exercise was the culmination of a series of Integral Experiment Requests (IER) that included the establishment of the Nuclear Criticality Experimental Research Center, (NCERC) the startup of the Godiva Reactor (IER-194), the establishment of a the Nuclear Accident Dosimetry Laboratory (NAD LAB) in Mercury, NV, and the determination of reference dosimetry values for the mixed neutron and photon radiation field of Godiva within NCERC.

  12. Uranium Dispersion and Dosimetry (UDAD) Code

    International Nuclear Information System (INIS)

    Momeni, M.H.; Yuan, Y.; Zielen, A.J.

    1979-05-01

    The Uranium Dispersion and Dosimetry (UDAD) Code provides estimates of potential radiation exposure to individuals and to the general population in the vicinity of a uranium processing facility. The UDAD Code incorporates the radiation dose from the airborne release of radioactive materials, and includes dosimetry of inhalation, ingestion, and external exposures. The removal of raioactive particles from a contaminated area by wind action is estimated, atmospheric concentrations of radioactivity from specific sources are calculated, and source depletion as a result of deposition, fallout, and ingrowth of radon daughters are included in a sector-averaged Gaussian plume dispersion model. The average air concentration at any given receptor location is assumed to be constant during each annual release period, but to increase from year to year because of resuspension. Surface contamination and deposition velocity are estimated. Calculation of the inhalation dose and dose rate to an individual is based on the ICRP Task Group Lung Model. Estimates of the dose to the bronchial epithelium of the lung from inhalation of radon and its short-lived daughters are calculated based on a dose conversion factor from the BEIR report. External radiation exposure includes radiation from airborne radionuclides and exposure to radiation from contaminated ground. Terrestrial food pathways include vegetation, meat, milk, poultry, and eggs. Internal dosimetry is based on ICRP recommendations. In addition, individual dose commitments, population dose commitments, and environmental dose commitments are computed. This code also may be applied to dispersion of any other pollutant

  13. The future of new calculation concepts in dosimetry based on the Monte Carlo Methods; Avenir des nouveaux concepts des calculs dosimetriques bases sur les methodes de Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Makovicka, L.; Vasseur, A.; Sauget, M.; Martin, E.; Gschwind, R.; Henriet, J. [Universite de Franche-Comte, Equipe IRMA/ENISYS/FEMTO-ST, UMR6174 CNRS, 25 - Montbeliard (France); Vasseur, A.; Sauget, M.; Martin, E.; Gschwind, R.; Henriet, J.; Salomon, M. [Universite de Franche-Comte, Equipe AND/LIFC, 90 - Belfort (France)

    2009-01-15

    Monte Carlo codes, precise but slow, are very important tools in the vast majority of specialities connected to Radiation Physics, Radiation Protection and Dosimetry. A discussion about some other computing solutions is carried out; solutions not only based on the enhancement of computer power, or on the 'biasing'used for relative acceleration of these codes (in the case of photons), but on more efficient methods (A.N.N. - artificial neural network, C.B.R. - case-based reasoning - or other computer science techniques) already and successfully used for a long time in other scientific or industrial applications and not only Radiation Protection or Medical Dosimetry. (authors)

  14. Standard Practice for Use of a Lif Photo-Fluorescent Film Dosimetry System

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2003-01-01

    1.1 This practice covers the handling, testing, and procedure for using a lithium fluoride (LiF)-based photo-fluorescent film dosimetry system to measure absorbed dose (relative to water) in materials irradiated by photons or electrons. Other alkali halides that may also exhibit photofluorescence (for example, NaCl, NaF, and KCl) are not covered in this practice. Although various alkali halides have been used for dosimetry for years utilizing thermoluminescence, the use of photoluminescence is relatively new. 1.2 This practice applies to photo-fluorescent film dosimeters (referred hereafter as photo-fluorescent dosimeters) that can be used within part or all of the following ranges: 1.2.1 Absorbed dose range of 5 10-2 to 3 102 kGy (1-3). 1.2.2 Absorbed dose rate range of 0.3 to 2 10 4 Gy/s (2-5)). 1.2.3 Radiation energy range for photons of 0.05 to 10 MeV (2). 1.2.4 Radiation energy range for electrons of 0.1 to 10 MeV (2). 1.2.5 Radiation temperature range of -20 to +60°C (6,7). 1.3 This standard doe...

  15. EURADOS strategic research agenda: vision for dosimetry of ionising radiation.

    Science.gov (United States)

    Rühm, W; Fantuzzi, E; Harrison, R; Schuhmacher, H; Vanhavere, F; Alves, J; Bottollier Depois, J F; Fattibene, P; Knežević, Ž; Lopez, M A; Mayer, S; Miljanić, S; Neumaier, S; Olko, P; Stadtmann, H; Tanner, R; Woda, C

    2016-02-01

    Since autumn 2012, the European Radiation Dosimetry Group (EURADOS) has been developing its Strategic Research Agenda (SRA), which is intended to contribute to the identification of future research needs in radiation dosimetry in Europe. The present article summarises-based on input from EURADOS Working Groups (WGs) and Voting Members-five visions in dosimetry and defines key issues in dosimetry research that are considered important for the next decades. The five visions include scientific developments required towards (a) updated fundamental dose concepts and quantities, (b) improved radiation risk estimates deduced from epidemiological cohorts, (c) efficient dose assessment for radiological emergencies, (d) integrated personalised dosimetry in medical applications and (e) improved radiation protection of workers and the public. The SRA of EURADOS will be used as a guideline for future activities of the EURADOS WGs. A detailed version of the SRA can be downloaded as a EURADOS report from the EURADOS website (www.eurados.org). © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  16. Theoretical basis for dosimetry

    International Nuclear Information System (INIS)

    Carlsson, G.A.

    1985-01-01

    Radiation dosimetry is fundamental to all fields of science dealing with radiation effects and is concerned with problems which are often intricate as hinted above. A firm scientific basis is needed to face increasing demands on accurate dosimetry. This chapter is an attempt to review and to elucidate the elements for such a basis. Quantities suitable for radiation dosimetry have been defined in the unique work to coordinate radiation terminology and usage by the International Commission on Radiation Units and Measurements, ICRU. Basic definitions and terminology used in this chapter conform with the recent ''Radiation Quantities and Units, Report 33'' of the ICRU

  17. EPR-dosimetry of ionizing radiation

    Science.gov (United States)

    Popova, Mariia; Vakhnin, Dmitrii; Tyshchenko, Igor

    2017-09-01

    This article discusses the problems that arise during the radiation sterilization of medical products. It is propose the solution based on alanine EPR-dosimetry. The parameters of spectrometer and methods of absorbed dose calculation are given. In addition, the problems that arise during heavy particles irradiation are investigated.

  18. Patient skin dosimetry in interventional cardiology in the Czech Republic

    International Nuclear Information System (INIS)

    Sukupova, L.; Novak, L.; Kala, P.; Cervinka, P.; Stasek, J.

    2011-01-01

    In this study, skin dosimetry of patients undergoing interventional cardiology procedures is presented. Three hospitals were included. Two methods were used for skin dosimetry-radiochromic dosimetry films and reconstruction of skin dose distribution based on examination protocol. Maximum skin doses (MSD) obtained from both methods were compared for 175 patients. For patients for whom the film MSD was >1 Gy, the reconstruction MSD differed from the film MSD in the range of ± 50 % for 83 % of patients. For remaining patients, the difference was higher and it was caused by longer fluoroscopy time. For 59 patients for whom the cumulative dose was known, the cumulative dose was compared with the film MSD. Skin dosimetry with radiochromic films is more accurate than the reconstruction method, but films do not include X-ray fields from lateral projections whilst reconstructions do. (authors)

  19. Hanford External Dosimetry Technical Basis Manual PNL-MA-842

    Energy Technology Data Exchange (ETDEWEB)

    Rathbone, Bruce A.

    2010-01-01

    manual by PNNL was discontinued beginning with Revision 0.2. Revision Log: Rev. 0 (2/25/2005) Major revision and expansion. Rev. 0.1 (3/12/2007) Updated Chapters 5, 6 and 9 to reflect change in default ring calibration factor used in HEDP dose calculation software. Factor changed from 1.5 to 2.0 beginning January 1, 2007. Pages on which changes were made are as follows: 5.23, 5.69, 5.78, 5.80, 5.82, 6.3, 6.5, 6.29, and 9.2. Rev 0.2 (8/28/2009) Updated Chapters 3, 5, 6, 8 and 9. Chapters 6 and 8 were significantly expanded. References in the Preface and Chapters 1, 2, 4, and 7 were updated to reflect updates to DOE documents. Approved by HPDAC on 6/2/2009. Rev 1.0 (1/1/2010) Major revision. Updated all chapters to reflect the Hanford site wide implementation on January 1, 2010 of new DOE requirements for occupational radiation protection. The new requirements are given in the June 8, 2007 amendment to 10 CFR 835 Occupational Radiation Protection (Federal Register, June 8, 2007. Title 10 Part 835. U.S., Code of Federal Regulations, Vol. 72, No. 110, 31904-31941). Revision 1.0 to the manual replaces ICRP 26 dosimetry concepts and terminology with ICRP 60 dosimetry concepts and terminology and replaces external dose conversion factors from ICRP 51 with those from ICRP 74 for use in measurement of operational quantities with dosimeters. Descriptions of dose algorithms and dosimeter response characteristics, and field performance were updated to reflect changes in the neutron quality factors used in the measurement of operational quantities.

  20. INTEGRATED OPERATIONAL DOSIMETRY SYSTEM AT CERN.

    Science.gov (United States)

    Dumont, Gérald; Pedrosa, Fernando Baltasar Dos Santos; Carbonez, Pierre; Forkel-Wirth, Doris; Ninin, Pierre; Fuentes, Eloy Reguero; Roesler, Stefan; Vollaire, Joachim

    2017-04-01

    CERN, the European Organization for Nuclear Research, upgraded its operational dosimetry system in March 2013 to be prepared for the first Long Shutdown of CERN's facilities. The new system allows the immediate and automatic checking and recording of the dosimetry data before and after interventions in radiation areas. To facilitate the analysis of the data in context of CERN's approach to As Low As Reasonably Achievable (ALARA), this new system is interfaced to the Intervention Management Planning and Coordination Tool (IMPACT). IMPACT is a web-based application widely used in all CERN's accelerators and their associated technical infrastructures for the planning, the coordination and the approval of interventions (work permit principle). The coupling of the operational dosimetry database with the IMPACT repository allows a direct and almost immediate comparison of the actual dose with the estimations, in addition to enabling the configuration of alarm levels in the dosemeter in function of the intervention to be performed. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. Diagnostic radiology dosimetry: status and trends

    International Nuclear Information System (INIS)

    Rivera M, T.

    2015-10-01

    Full text: Medical radiation is by far the largest man-made source of public exposure to ionizing radiation. Since 1970 the expression of protection standards shifted from a dose- to a risk-based approach, with dose limits established to yield risks to radiation workers comparable with those for workers in other safe industries. Another hand, worldwide interest in patient dose measurement was stimulated by the publication of Patient Dose Reduction in Diagnostic Radiology by the UK National Radiological Protection Board (NRPB). In response to heightened awareness of the importance of patient dose contributed by radiology procedures, there has been a general trend to effect control of patient doses by applying the principles of optimization coupled with an increase in regulatory enforcement. In this sense, thermoluminescent dosimetry (TLD) has been actively proposed in the last 3 decades thanks to their successful applications in diagnostic radiology. At the same time, it is emerged as the best radiation dosimetry method. The present work presents advantages of thermoluminescent dosimetry for X-ray beams measurements and its optimization. (Author)

  2. Diagnostic radiology dosimetry: status and trends

    Energy Technology Data Exchange (ETDEWEB)

    Rivera M, T., E-mail: trivera@ipn.mx [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Av. Legaria 694, 11500 Mexico D. F. (Mexico)

    2015-10-15

    Full text: Medical radiation is by far the largest man-made source of public exposure to ionizing radiation. Since 1970 the expression of protection standards shifted from a dose- to a risk-based approach, with dose limits established to yield risks to radiation workers comparable with those for workers in other safe industries. Another hand, worldwide interest in patient dose measurement was stimulated by the publication of Patient Dose Reduction in Diagnostic Radiology by the UK National Radiological Protection Board (NRPB). In response to heightened awareness of the importance of patient dose contributed by radiology procedures, there has been a general trend to effect control of patient doses by applying the principles of optimization coupled with an increase in regulatory enforcement. In this sense, thermoluminescent dosimetry (TLD) has been actively proposed in the last 3 decades thanks to their successful applications in diagnostic radiology. At the same time, it is emerged as the best radiation dosimetry method. The present work presents advantages of thermoluminescent dosimetry for X-ray beams measurements and its optimization. (Author)

  3. Student Perceptions of an Online Medical Dosimetry Program

    International Nuclear Information System (INIS)

    Lenards, Nishele

    2011-01-01

    The University of Wisconsin-La Crosse offers the first online medical dosimetry program in the nation. There is no data to research a program of this type. This research consisted of the evaluation of other distance education programs including health profession programs in addition to face-to-face medical dosimetry programs. There was a need to collect and analyze student perceptions of online learning in medical dosimetry. This research provided a guide for future implementation by other programs as well as validated the University of Wisconsin-La Crosse program. Methodology used consisted of an electronic survey sent to all previous and currently enrolled students in the University of Wisconsin-La Crosse medical dosimetry program. The survey was both quantitative and qualitative in demonstrating attitudinal perceptions of students in the program. Quantitative data was collected and analyzed using a 5-point Likert scale. Qualitative data was gathered based on the open-ended responses and the identifying themes from the responses. The results demonstrated an overall satisfaction with this program, the instructor, and the online courses. Students felt a sense of belonging to the courses and the program. Considering that a majority of the students had never taken an online course previously, the students felt there were no technology issues. Future research should include an evaluation of board exam statistics for students enrolled in the online and face-to-face medical dosimetry programs.

  4. Reactor Dosimetry State of the Art 2008

    Science.gov (United States)

    Voorbraak, Wim; Debarberis, Luigi; D'Hondt, Pierre; Wagemans, Jan

    2009-08-01

    Oral session 1: Retrospective dosimetry. Retrospective dosimetry of VVER 440 reactor pressure vessel at the 3rd unit of Dukovany NPP / M. Marek ... [et al.]. Retrospective dosimetry study at the RPV of NPP Greifswald unit 1 / J. Konheiser ... [et al.]. Test of prototype detector for retrospective neutron dosimetry of reactor internals and vessel / K. Hayashi ... [et al.]. Neutron doses to the concrete vessel and tendons of a magnox reactor using retrospective dosimetry / D. A. Allen ... [et al.]. A retrospective dosimetry feasibility study for Atucha I / J. Wagemans ... [et al.]. Retrospective reactor dosimetry with zirconium alloy samples in a PWR / L. R. Greenwood and J. P. Foster -- Oral session 2: Experimental techniques. Characterizing the Time-dependent components of reactor n/y environments / P. J. Griffin, S. M. Luker and A. J. Suo-Anttila. Measurements of the recoil-ion response of silicon carbide detectors to fast neutrons / F. H. Ruddy, J. G. Seidel and F. Franceschini. Measurement of the neutron spectrum of the HB-4 cold source at the high flux isotope reactor at Oak Ridge National Laboratory / J. L. Robertson and E. B. Iverson. Feasibility of cavity ring-down laser spectroscopy for dose rate monitoring on nuclear reactor / H. Tomita ... [et al.]. Measuring transistor damage factors in a non-stable defect environment / D. B. King ... [et al.]. Neutron-detection based monitoring of void effects in boiling water reactors / J. Loberg ... [et al.] -- Poster session 1: Power reactor surveillance, retrospective dosimetry, benchmarks and inter-comparisons, adjustment methods, experimental techniques, transport calculations. Improved diagnostics for analysis of a reactor pulse radiation environment / S. M. Luker ... [et al.]. Simulation of the response of silicon carbide fast neutron detectors / F. Franceschini, F. H. Ruddy and B. Petrović. NSV A-3: a computer code for least-squares adjustment of neutron spectra and measured dosimeter responses / J. G

  5. Overview of 3-year experience with large-scale electronic portal imaging device-based 3-dimensional transit dosimetry

    NARCIS (Netherlands)

    Mijnheer, Ben J.; González, Patrick; Olaciregui-Ruiz, Igor; Rozendaal, Roel A.; van Herk, Marcel; Mans, Anton

    2015-01-01

    To assess the usefulness of electronic portal imaging device (EPID)-based 3-dimensional (3D) transit dosimetry in a radiation therapy department by analyzing a large set of dose verification results. In our institution, routine in vivo dose verification of all treatments is performed by means of 3D

  6. A dosimetry based on artificial neural net theory in treatment of Graves disease

    International Nuclear Information System (INIS)

    Yang Ping; Luo Dongyun; Lin Yongxia; Zeng Shiquan

    2002-01-01

    Objective: To study the feasibility of radioactive treatment of Graves disease with dosimetry of 131 I in novel method by computer. Methods: The database comprised 206 selected Graves disease cases and according to this database the nonlinear functions could be inferred consequently, then 206 Graves disease patients were divided into two groups. The group one, 109 patients, was treated with back-propagation (BP) dosimetry method. The group two was treated with traditional method. The results were analyzed. Results: Group one had an effective rate of 93.5%, cure rate of 90.8%, recurrent rate of 3.6% and early stage of hypothyroidism rate of 3.6%. Group two had an effective rate of 90.7%, cure rate of 85.5%, recurrent rate of 5.1% and early stage of hypothyroidism rate of 5.1%. Conclusion: The BP method is efficient and the results reflect that this method might increase the accuracy of the dosimetry of 131 I and reduce recurrent rate and early stage of hypothyroidism occurrence

  7. High-dosage dosimetry programme of the IAEA

    International Nuclear Information System (INIS)

    Mehta, K.

    1999-01-01

    The high-dose dosimetry programme was initiated by the International Atomic Energy Agency in 1977. Like any other Agency programme, this one has various activities. These cover: research contracts and research agreements, co-ordinated research projects (CRP), training courses, and laboratory-based activities. The Agency's dose quality audit service (International Dose Assurance Service, IDAS), initiated in 1985, is one of the key elements of the programme. At earlier times, the technical part was operated through a laboratory in Germany. However, after purchasing the Bruker ESR spectrometer, the entire service has been operated from the Agency since 1992. This audit service has served well the needs of various institutes around the world involved with radiation processing. We have had two Co-ordinated Research Projects (the second one is in its last year) over the last several years. Both were/are aimed at standardization of dosimetry for radiation processing. Nine or ten participants of each CRP were about evenly distributed between the developed and developing Member States. In collaboration with the Food and Environmental Protection Section and the Industrial Applications and Chemistry Section, the Dosimetry and Medical Radiation Physics Section has participated in several training courses; these have been mainly regional courses. This collaboration has worked well since such courses combine specific radiation processing applications with the needs of good dosimetry and process control. Also, the Agency has organised several dose intercomparisons in recent time. The activities of the high-dose dosimetry programme since the last symposium (November 1990) are reviewed here. (author)

  8. Personnel neutron dosimetry using electrochemically etched CR-39 foils

    International Nuclear Information System (INIS)

    Hankins, D.E.; Homann, S.; Westermark, J.

    1986-01-01

    A personnel neutron dosimetry system has been developed based on the electrochemical etching of CR-39 plastic at elevated temperatures. The doses obtained using this dosimeter system are more accurate than those obtained using other dosimetry systems, especially when varied neutron spectra are encountered. This Cr-39 dosimetry system does not have the severe energy dependence that exists with albedo neutron dosimeters or the fading and reading problems encountered with NTA film. The dosimetry system employs an electrochemical etch procedure that be used to process large numbers of Cr-39 dosimeters. The etch procedure is suitable for operations where the number of personnel requires that many CR-39 dosimeters be processed. Experience shows that one full-time technician can etch and evaluate 2000 foils per month. The energy response to neutrons is fairly flat from about 80 keV to 3.5 MeV, but drops by about a factor of three in the 13 to 16 MeV range. The sensitivity of the dosimetry system is about 7 tracks/cm 2 /mrem, with a background equivalent to about 8 mrem for new CR-39 foils. The limit of sensitivity is approximately 10 mrem. The dosimeter has a significant variation in directional dependence, dropping to about 20% at 90 0 . This dosimeter has been used for personnel neutron dosimetry at the Lawrence Livermore National Laboratory for more tha 18 months. 6 refs., 23 figs., 2 tabs

  9. Gel dosimetry for conformal radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Gambarini, G [Department of Physics of the University and INFN, Milan (Italy)

    2005-07-01

    With the continuum development of conformal radio therapies, aimed at delivering high dose to tumor tissue and low dose to the healthy tissue around, the necessities has appeared of suitable improvement of dosimetry techniques giving the possibility of obtaining dose images to be compared with diagnostic images. Also if wide software has been developed for calculating dose distributions in the fields of various radiotherapy units, experimental verifications are necessary, in particular in the case of complex geometries in conformal radiotherapy. Gel dosimetry is a promising method for imaging the absorbed dose in tissue-equivalent phantoms, with the possibility of 3D reconstruction of the spatial dose distribution, with milli metric resolution. Optical imaging of gel dosimeters, based on visible light absorbance analysis, has shown to be a reliable technique for achieving dose distributions. (Author)

  10. Personal dosimetry in Kazakhstan

    International Nuclear Information System (INIS)

    Khvoshnyanskaya, I.R.; Vdovichenko, V.G.; Lozbin, A.Yu.

    2003-01-01

    KATEP-AE Radiation Laboratory is the first organization in Kazakhstan officially licensed by the Kazakhstan Atomic Energy Committee to provide individual dosimetry services. The Laboratory was established according to the international standards. Nowadays it is the largest company providing personal dosimetry services in the Republic of Kazakhstan. (author)

  11. Performance testing of UK personal dosimetry laboratories

    International Nuclear Information System (INIS)

    Marshall, T.O.

    1985-01-01

    The proposed Ionising Radiations Regulations will require all UK personal dosimetry laboratories that monitor classified personnel to be approved for personal dosimetry by the Health and Safety Executive. It is suggested that these approvals should be based on general and supplementary criteria published by the British Calibration Service (BCS) for laboratory approval for the provision of personal dosimetry services. These criteria specify certain qualitative requirements and also indicate the need for regular tests of performance to be carried out to ensure constancy of dosimetric standards. This report concerns the latter. The status of the BCS criteria is discussed and the need for additional documents to cover new techniques and some modifications to existing documents is indicated. A means is described by which the technical performance of laboratories, concerned with personal monitoring for external radiations, can be assessed, both initially and ongoing. The costs to establish the scheme and operate it are also estimated. (author)

  12. Dosimetry audits and intercomparisons in radiotherapy: A Malaysian profile

    International Nuclear Information System (INIS)

    Noor, Noramaliza M.; Nisbet, A.; Hussein, M.; Chu S, Sarene; Kadni, T.; Abdullah, N.; Bradley, D.A.

    2017-01-01

    Quality audits and intercomparisons are important in ensuring control of processes in any system of endeavour. Present interest is in control of dosimetry in teletherapy, there being a need to assess the extent to which there is consistent radiation dose delivery to the patient. In this study we review significant factors that impact upon radiotherapy dosimetry, focusing upon the example situation of radiotherapy delivery in Malaysia, examining existing literature in support of such efforts. A number of recommendations are made to provide for increased quality assurance and control. In addition to this study, the first level of intercomparison audit i.e. measuring beam output under reference conditions at eight selected Malaysian radiotherapy centres is checked; use being made of 9 µm core diameter Ge-doped silica fibres (Ge-9 µm). The results of Malaysian Secondary Standard Dosimetry Laboratory (SSDL) participation in the IAEA/WHO TLD postal dose audit services during the period between 2011 and 2015 will also been discussed. In conclusion, following review of the development of dosimetry audits and the conduct of one such exercise in Malaysia, it is apparent that regular periodic radiotherapy audits and intercomparison programmes should be strongly supported and implemented worldwide. The programmes to-date demonstrate these to be a good indicator of errors and of consistency between centres. A total of ei+ght beams have been checked in eight Malaysian radiotherapy centres. One out of the eight beams checked produced an unacceptable deviation; this was found to be due to unfamiliarity with the irradiation procedures. Prior to a repeat measurement, the mean ratio of measured to quoted dose was found to be 0.99 with standard deviation of 3%. Subsequent to the repeat measurement, the mean distribution was 1.00, and the standard deviation was 1.3%. - Highlights: • We review significant factors that impact upon radiotherapy dosimetry, • We carried out the

  13. Factors influencing EPR dosimetry in fingernails

    International Nuclear Information System (INIS)

    Dubner, D.L.; Spinella, M.R.; Bof, E.

    2010-01-01

    The technique based on the detection of ionizing radiation induced radicals by EPR in tooth enamel is an established method for the dosimetry of exposed persons in radiological emergencies. Dosimetry based on EPR spectral analysis of fingernail clippings, currently under development, has the practical advantage of the easier sample collection. A limiting factor is that overlapping the radiation induced signal (RIS), fingernails have shown the presence of two mechanically induced signals, called MIS1 and MIS2, due to elastic and plastic deformation respectively, at the time of fingernails cutting. With a water treatment, MIS1 is eliminated while MIS2 is considerably reduced. The calibration curves needed for radiation accident dosimetry should have 'universal' characteristics, ie. Represent the variability that can be found in different individuals. Early studies were directed to the analysis of factors affecting the development of such universal calibration curves. The peak to peak amplitude of the signal before and after the water treatment as well as the effect of size and number of clippings were studied. Furthermore, the interpersonal and intrapersonal variability were analyzed. Taking into account these previous studies, the optimal conditions for measurement were determined and EPR spectra of samples irradiated at different doses were used for the developing of dose-response curves. This paper presents the analysis of the results.(authors) [es

  14. Dosimetric analysis at ICRU reference points in HDR-brachytherapy of cervical carcinoma.

    Science.gov (United States)

    Eich, H T; Haverkamp, U; Micke, O; Prott, F J; Müller, R P

    2000-01-01

    In vivo dosimetry in bladder and rectum as well as determining doses on suggested reference points following the ICRU report 38 contribute to quality assurance in HDR-brachytherapy of cervical carcinoma, especially to minimize side effects. In order to gain information regarding the radiation exposure at ICRU reference points in rectum, bladder, ureter and regional lymph nodes those were calculated (digitalisation) by means of orthogonal radiographs of 11 applications in patients with cervical carcinoma, who received primary radiotherapy. In addition, the doses at the ICRU rectum reference point was compared to the results of in vivo measurements in the rectum. The in vivo measurements were by factor 1.5 below the doses determined for the ICRU rectum reference point (4.05 +/- 0.68 Gy versus 6.11 +/- 1.63 Gy). Reasons for this were: calibration errors, non-orthogonal radiographs, movement of applicator and probe in the time span between X-ray and application, missing connection of probe and anterior rectal wall. The standard deviation of calculations at ICRU reference points was on average +/- 30%. Possible reasons for the relatively large standard deviation were difficulties in defining the points, identifying them on radiographs and the different locations of the applicators. Although 3 D CT, US or MR based treatment planning using dose volume histogram analysis is more and more established, this simple procedure of marking and digitising the ICRU reference points lengthened treatment planning only by 5 to 10 minutes. The advantages of in vivo dosimetry are easy practicability and the possibility to determine rectum doses during radiation. The advantages of computer-aided planning at ICRU reference points are that calculations are available before radiation and that they can still be taken into account for treatment planning. Both methods should be applied in HDR-brachytherapy of cervical carcinoma.

  15. Comparison of Combined X-Ray Radiography and Magnetic Resonance (XMR) Imaging-Versus Computed Tomography-Based Dosimetry for the Evaluation of Permanent Prostate Brachytherapy Implants

    International Nuclear Information System (INIS)

    Acher, Peter; Rhode, Kawal; Morris, Stephen; Gaya, Andrew; Miquel, Marc; Popert, Rick; Tham, Ivan; Nichol, Janette; McLeish, Kate; Deehan, Charles; Dasgupta, Prokar; Beaney, Ronald; Keevil, Stephen F.

    2008-01-01

    Purpose: To present a method for the dosimetric analysis of permanent prostate brachytherapy implants using a combination of stereoscopic X-ray radiography and magnetic resonance (MR) imaging (XMR) in an XMR facility, and to compare the clinical results between XMR- and computed tomography (CT)-based dosimetry. Methods and Materials: Patients who had received nonstranded iodine-125 permanent prostate brachytherapy implants underwent XMR and CT imaging 4 weeks later. Four observers outlined the prostate gland on both sets of images. Dose-volume histograms (DVHs) were derived, and agreement was compared among the observers and between the modalities. Results: A total of 30 patients were evaluated. Inherent XMR registration based on prior calibration and optical tracking required a further automatic seed registration step that revealed a median root mean square registration error of 4.2 mm (range, 1.6-11.4). The observers agreed significantly more closely on prostate base and apex positions as well as outlining contours on the MR images than on those from CT. Coefficients of variation were significantly higher for observed prostate volumes, D90, and V100 parameters on CT-based dosimetry as opposed to XMR. The XMR-based dosimetry showed little agreement with that from CT for all observers, with D90 95% limits of agreement ranges of 65, 118, 79, and 73 Gy for Observers 1, 2, 3, and 4, respectively. Conclusions: The study results showed that XMR-based dosimetry offers an alternative to other imaging modalities and registration methods with the advantages of MR-based prostate delineation and confident three-dimensional reconstruction of the implant. The XMR-derived dose-volume histograms differ from the CT-derived values and demonstrate less interobserver variability

  16. MO-B-BRB-00: Three Dimensional Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2016-06-15

    Full three-dimensional (3D) dosimetry using volumetric chemical dosimeters probed by 3D imaging systems has long been a promising technique for the radiation therapy clinic, since it provides a unique methodology for dose measurements in the volume irradiated using complex conformal delivery techniques such as IMRT and VMAT. To date true 3D dosimetry is still not widely practiced in the community; it has been confined to centres of specialized expertise especially for quality assurance or commissioning roles where other dosimetry techniques are difficult to implement. The potential for improved clinical applicability has been advanced considerably in the last decade by the development of improved 3D dosimeters (e.g., radiochromic plastics, radiochromic gel dosimeters and normoxic polymer gel systems) and by improved readout protocols using optical computed tomography or magnetic resonance imaging. In this session, established users of some current 3D chemical dosimeters will briefly review the current status of 3D dosimetry, describe several dosimeters and their appropriate imaging for dose readout, present workflow procedures required for good dosimetry, and analyze some limitations for applications in select settings. We will review the application of 3D dosimetry to various clinical situations describing how 3D approaches can complement other dose delivery validation approaches already available in the clinic. The applications presented will be selected to inform attendees of the unique features provided by full 3D techniques. Learning Objectives: L. John Schreiner: Background and Motivation Understand recent developments enabling clinically practical 3D dosimetry, Appreciate 3D dosimetry workflow and dosimetry procedures, and Observe select examples from the clinic. Sofie Ceberg: Application to dynamic radiotherapy Observe full dosimetry under dynamic radiotherapy during respiratory motion, and Understand how the measurement of high resolution dose data in an

  17. Modeling the impact of prostate edema on LDR brachytherapy: a Monte Carlo dosimetry study based on a 3D biphasic finite element biomechanical model

    Science.gov (United States)

    Mountris, K. A.; Bert, J.; Noailly, J.; Rodriguez Aguilera, A.; Valeri, A.; Pradier, O.; Schick, U.; Promayon, E.; Gonzalez Ballester, M. A.; Troccaz, J.; Visvikis, D.

    2017-03-01

    Prostate volume changes due to edema occurrence during transperineal permanent brachytherapy should be taken under consideration to ensure optimal dose delivery. Available edema models, based on prostate volume observations, face several limitations. Therefore, patient-specific models need to be developed to accurately account for the impact of edema. In this study we present a biomechanical model developed to reproduce edema resolution patterns documented in the literature. Using the biphasic mixture theory and finite element analysis, the proposed model takes into consideration the mechanical properties of the pubic area tissues in the evolution of prostate edema. The model’s computed deformations are incorporated in a Monte Carlo simulation to investigate their effect on post-operative dosimetry. The comparison of Day1 and Day30 dosimetry results demonstrates the capability of the proposed model for patient-specific dosimetry improvements, considering the edema dynamics. The proposed model shows excellent ability to reproduce previously described edema resolution patterns and was validated based on previous findings. According to our results, for a prostate volume increase of 10-20% the Day30 urethra D10 dose metric is higher by 4.2%-10.5% compared to the Day1 value. The introduction of the edema dynamics in Day30 dosimetry shows a significant global dose overestimation identified on the conventional static Day30 dosimetry. In conclusion, the proposed edema biomechanical model can improve the treatment planning of transperineal permanent brachytherapy accounting for post-implant dose alterations during the planning procedure.

  18. The Latin American Biological Dosimetry Network (LBDNet)

    International Nuclear Information System (INIS)

    Garcia, O.; Lamadrid, A.I.; Gonzalez, J.E.; Romero, I.; Mandina, T.; Di Giorgio, M.; Radl, A.; Taja, M.R.; Sapienza, C.E.; Deminge, M.M.; Fernandez Rearte, J.; Stuck Oliveira, M.; Valdivia, P.; Guerrero-Carbajal, C.; Arceo Maldonado, C.; Cortina Ramirez, G.E.; Espinoza, M.; Martinez-Lopez, W.; Di Tomasso, M.

    2016-01-01

    Biological Dosimetry is a necessary support for national radiation protection programmes and emergency response schemes. The Latin American Biological Dosimetry Network (LBDNet) was formally founded in 2007 to provide early biological dosimetry assistance in case of radiation emergencies in the Latin American Region. Here are presented the main topics considered in the foundational document of the network, which comprise: mission, partners, concept of operation, including the mechanism to request support for biological dosimetry assistance in the region, and the network capabilities. The process for network activation and the role of the coordinating laboratory during biological dosimetry emergency response is also presented. This information is preceded by historical remarks on biological dosimetry cooperation in Latin America. A summary of the main experimental and practical results already obtained by the LBDNet is also included. (authors)

  19. Improving neutron dosimetry using bubble detector technology

    International Nuclear Information System (INIS)

    Buckner, M.A.

    1993-02-01

    Providing accurate neutron dosimetry for a variety of neutron energy spectra is a formidable task for any dosimetry system. Unless something is known about the neutron spectrum prior to processing the dosimeter, the calculated dose may vary greatly from that actually encountered; that is until now. The entrance of bubble detector technology into the field of neutron dosimetry has eliminated the necessity of having an a priori knowledge of the neutron energy spectra. Recently, a new approach in measuring personnel neutron dose equivalent was developed at Oak Ridge National Laboratory. By using bubble detectors in combination with current thermoluminescent dosimeters (TLDs) as a Combination Personnel Neutron Dosimeter (CPND), not only is it possible to provide accurate dose equivalent results, but a simple four-interval neutron energy spectrum is obtained as well. The components of the CPND are a Harshaw albedo TLD and two bubble detectors with theoretical energy thresholds of 100 key and 1500 keV. Presented are (1) a synoptic history surrounding emergence of bubble detector technology, (2) a brief overview of the current theory on mechanisms of interaction, (3) the data and analysis process involved in refining the response functions, (4) performance evaluation of the original CPND and a reevaluation of the same data under the modified method, (5) the procedure used to determine the reference values of component fluence and dose equivalent for field assessment, (6) analysis of the after-modification results, (7) a critique of some currently held assumptions, offering some alternative explanations, and (8) thoughts concerning potential applications and directions for future research

  20. Criticality accident dosimetry systems: an international intercomparison at the SILENE reactor in 2002.

    Science.gov (United States)

    Médioni, R; Asselineau, B; Verrey, B; Trompier, F; Itié, C; Texier, C; Muller, H; Pelcot, G; Clairand, I; Jacquet, X; Pochat, J L

    2004-01-01

    In criticality accident dosimetry and more generally for high dose measurements, special techniques are used to measure separately the gamma ray and neutron components of the dose. To improve these techniques and to check their dosimetry systems (physical and/or biological), a total of 60 laboratories from 29 countries (America, Europe, Asia) participated in an international intercomparaison, which took place in France from 9 to 21 June 2002, at the SILENE reactor in Valduc and at a pure gamma source in Fontenay-aux-Roses. This intercomparison was jointly organised by the IRSN and the CEA with the help of the NEA/OCDE and was partly supported by the European Communities. This paper describes the aim of this intercomparison, the techniques used by the participants and the two radiation sources and their characteristics. The experimental arrangements of the dosemeters for the irradiations in free air or on phantoms are given. Then the dosimetric quantities measured and reported by the participants are summarised, analysed and compared with the reference values. The present paper concerns only the physical dosimetry and essentially experiments performed on the SILENE facility. The results obtained with the biological dosimetry are published in two other papers of this issue.

  1. Relationship between student selection criteria and learner success for medical dosimetry students

    International Nuclear Information System (INIS)

    Baker, Jamie; Tucker, Debra; Raynes, Edilberto; Aitken, Florence; Allen, Pamela

    2016-01-01

    Medical dosimetry education occupies a specialized branch of allied health higher education. Noted international shortages of health care workers, reduced university funding, limitations on faculty staffing, trends in learner attrition, and increased enrollment of nontraditional students force medical dosimetry educational leadership to reevaluate current admission practices. Program officials wish to select medical dosimetry students with the best chances of successful graduation. The purpose of the quantitative ex post facto correlation study was to investigate the relationship between applicant characteristics (cumulative undergraduate grade point average (GPA), science grade point average (SGPA), prior experience as a radiation therapist, and previous academic degrees) and the successful completion of a medical dosimetry program, as measured by graduation. A key finding from the quantitative study was the statistically significant positive correlation between a student's previous degree and his or her successful graduation from the medical dosimetry program. Future research investigations could include a larger research sample, representative of more medical dosimetry student populations, and additional studies concerning the relationship of previous work as a radiation therapist and the effect on success as a medical dosimetry student. Based on the quantitative correlation analysis, medical dosimetry leadership on admissions committees could revise student selection rubrics to place less emphasis on an applicant's undergraduate cumulative GPA and increase the weight assigned to previous degrees.

  2. Relationship between student selection criteria and learner success for medical dosimetry students

    Energy Technology Data Exchange (ETDEWEB)

    Baker, Jamie, E-mail: jabaker@mdanderson.org [Medical Dosimetry Program, School of Health Professions, The University of Texas MD Anderson Cancer Center School of Health Professions, Houston, TX (United States); Tucker, Debra [Arizona State University, Phoenix, AZ (United States); Raynes, Edilberto [University of Phoenix, Phoenix, AZ (United States); Aitken, Florence [University of Nevada, Las Vegas, NV (United States); Allen, Pamela [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX (United States)

    2016-04-01

    Medical dosimetry education occupies a specialized branch of allied health higher education. Noted international shortages of health care workers, reduced university funding, limitations on faculty staffing, trends in learner attrition, and increased enrollment of nontraditional students force medical dosimetry educational leadership to reevaluate current admission practices. Program officials wish to select medical dosimetry students with the best chances of successful graduation. The purpose of the quantitative ex post facto correlation study was to investigate the relationship between applicant characteristics (cumulative undergraduate grade point average (GPA), science grade point average (SGPA), prior experience as a radiation therapist, and previous academic degrees) and the successful completion of a medical dosimetry program, as measured by graduation. A key finding from the quantitative study was the statistically significant positive correlation between a student's previous degree and his or her successful graduation from the medical dosimetry program. Future research investigations could include a larger research sample, representative of more medical dosimetry student populations, and additional studies concerning the relationship of previous work as a radiation therapist and the effect on success as a medical dosimetry student. Based on the quantitative correlation analysis, medical dosimetry leadership on admissions committees could revise student selection rubrics to place less emphasis on an applicant's undergraduate cumulative GPA and increase the weight assigned to previous degrees.

  3. Development of A-bomb survivor dosimetry

    International Nuclear Information System (INIS)

    Kerr, G.D.

    1995-01-01

    An all important datum in risk assessment is the radiation dose to individual survivors of the bombings in Hiroshima and Nagasaki. The first set of dose estimates for survivors was based on a dosimetry system developed in 1957 by the Oak Ridge National Laboratory (ORNL). These Tentative 1957 Doses (T57D) were later replaced by a more extensive and refined set of Tentative 1965 Doses (T65D). The T65D system of dose estimation for survivors was also developed at ORNL and served as a basis for risk assessment throughout the 1970s. In the late 1970s, it was suggested that there were serious inadequacies with the T65D system, and these inadequacies were the topic of discussion at two symposia held in 1981. In early 1983, joint US- Japan research programs were established to conduct a thorough review of all aspects of the radiation dosimetry for the Hiroshima and Nagasaki A-bomb survivors. A number of important contributions to this review were made by ORNL staff members. The review was completed in 1986 and a new Dosimetry System 1986 (DS86) was adopted for use. This paper discusses the development of the various systems of A-bomb survivor dosimetry, and the status of the current DS86 system as it is being applied in the medical follow-up studies of the A-bomb survivors and their offspring

  4. Development of A-bomb survivor dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Kerr, G.D.

    1995-12-31

    An all important datum in risk assessment is the radiation dose to individual survivors of the bombings in Hiroshima and Nagasaki. The first set of dose estimates for survivors was based on a dosimetry system developed in 1957 by the Oak Ridge National Laboratory (ORNL). These Tentative 1957 Doses (T57D) were later replaced by a more extensive and refined set of Tentative 1965 Doses (T65D). The T65D system of dose estimation for survivors was also developed at ORNL and served as a basis for risk assessment throughout the 1970s. In the late 1970s, it was suggested that there were serious inadequacies with the T65D system, and these inadequacies were the topic of discussion at two symposia held in 1981. In early 1983, joint US- Japan research programs were established to conduct a thorough review of all aspects of the radiation dosimetry for the Hiroshima and Nagasaki A-bomb survivors. A number of important contributions to this review were made by ORNL staff members. The review was completed in 1986 and a new Dosimetry System 1986 (DS86) was adopted for use. This paper discusses the development of the various systems of A-bomb survivor dosimetry, and the status of the current DS86 system as it is being applied in the medical follow-up studies of the A-bomb survivors and their offspring.

  5. EPID-based in vivo dosimetry for stereotactic body radiotherapy of non-small cell lung tumors: Initial clinical experience.

    Science.gov (United States)

    Consorti, R; Fidanzio, A; Brainovich, V; Mangiacotti, F; De Spirito, M; Mirri, M A; Petrucci, A

    2017-10-01

    EPID-based in vivo dosimetry (IVD) has been implemented for stereotactic body radiotherapy treatments of non-small cell lung cancer to check both isocenter dose and the treatment reproducibility comparing EPID portal images. 15 patients with lung tumors of small dimensions and treated with volumetric modulated arc therapy were enrolled for this initial experience. IVD tests supplied ratios R between in vivo reconstructed and planned isocenter doses. Moreover a γ-like analysis between daily EPID portal images and a reference one, in terms of percentage of points with γ-value smaller than 1, P γlevels of 5% for R ratio, P γlevel, and an average P γ90%. Paradigmatic discrepancies were observed in three patients: a set-up error and a patient morphological change were identified thanks to CBCT image analysis whereas the third discrepancy was not fully justified. This procedure can provide improved patient safety as well as a first step to integrate IVD and CBCT dose recalculation. Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  6. Thermoelectric neutron dosimetry: a short introduction

    International Nuclear Information System (INIS)

    Mathieu, F.; Meier, R.; Debrue, J.; Leonard, F.; Schubert, W.

    1977-01-01

    The paper gives a short introduction and state-of-the-art account of an unconventional, non destructive neutron dosimetry method based on monitoring the neutron fluence dependent changes of the thermoelectric properties of base metals and alloys. The basic principles are exposed and illustrated with experimental data obtained during an exploratory irradiation in the BR2 reactor

  7. Dosimetry of Gamma Knife and linac-based radiosurgery using radiochromic and diode detectors

    International Nuclear Information System (INIS)

    Somigliana, A.; Borelli, S.; Zonca, G.; Pignoli, E.; Loi, G.; Marchesini, R.; Cattaneo, G.M.; Fiorino, C.; Vecchio, A. del; Calandrino, R.

    1999-01-01

    In stereotactic radiosurgery the choice of appropriate detectors, whether for absolute or relative dosimetry, is very important due to the steep dose gradient and the incomplete lateral electronic equilibrium. For both linac-based and Leksell Gamma Knife radiosurgery units, we tested the use of calibrated radiochromic film to measure absolute doses and relative dose distributions. In addition a small diode was used to estimate the relative output factors. The data obtained using radiochromic and diode detectors were compared with measurements performed with other conventional methods of dosimetry, with calculated values by treatment planning systems and with data prestored in the treatment planning system supplied by the Leksell Gamma Knife (LGK) vendor. Two stereotactic radiosurgery techniques were considered: Leksell Gamma Knife (using γ-rays from 60 Co) and linac-based radiosurgery (LR) (6 MV x-rays). Different detectors were used for both relative and absolute dosimetry: relative output factors (OFs) were estimated by using radiochromic and radiographic films and a small diode; relative dose distributions in the axial and coronal planes of a spherical polystyrene phantom were measured using radiochromic film and calculated by two different treatment planning systems (TPSs). The absolute dose at the sphere centre was measured by radiochromic film and a small ionization chamber. An accurate selection of radiochromic film was made: samples of unexposed film showing a percentage standard deviation of less than 3% were used for relative dose profiles, and for absolute dose and OF evaluations this value was reduced to 1.5%. Moreover a proper calibration curve was made for each set of measurements. With regard to absolute doses, the results obtained with the ionization chamber are in good correlation with radiochromic film-generated data, for both LGK and LR, showing a dose difference of less than 1%. The output factor evaluations, performed using different methods

  8. SU-G-TeP2-03: Comparison of Standard Dosimetry Protocol in Japan and AAPM TG-51 Addendum in Order to Establish Optimal Dosimetry for FFF Beam

    Energy Technology Data Exchange (ETDEWEB)

    Matsunaga, T; Adachi, Y [Department of Radiology, Seirei Hamamatsu General Hospital, Hamamatsu, Shizuoka (Japan); Hayashi, N [Graduate School of Health Sciences, Fujita Health University, Tayoake, Aichi (Japan); Nozue, M [Department of Radiation Oncology, Seirei Hamamtsu General Hospital, Hamamatsu, Shizuoka (Japan)

    2016-06-15

    Purpose: Japan Standard Dosimetry of Absorbed dose to water in external beam radiotherapy (JSDP12) is widely used to measure radiation dose in radiotherapy. However, JSDP12 does not take flattening-filter-free (FFF) beam into consideration. In addition, JSDP12 applied TPR20,10 for dose quality index for photon beam. The purpose of this study is to compare JSDP12 with AAPM TG-51 addendum in order to establish optimal dosimetry procedure for FFF beam. Method: We evaluated the ion-recombination factor (ks) and the correction factor of radial beam profile (Prp) in FFF beam dosimetry. The ks was introduced by 2 voltages method and verified by Jaffe’s plot. The Prp was given by both film measurement and calculation of treatment planning system, and compared them. Next, we compared the dose quality indexes (kQ) between TPR20,10 method and PDD(10)x method. Finally we considered optimal dosimetry protocol for FFF photon beam using JSDP12 with referring TG-51 addendum protocols. The FFF photon beams of 6 MV (6X-FFF) and 10 MV (10X-FFF) from TrueBeam were investigated in this study. Results: The ks for 6X-FFF and 10X-FFF beams were 1.005 and 1.010, respectively. The Prp of 0.6 cc ionization chamber for 6X-FFF and 10X-FFF beams (Film, TPS) were (1.004, 1.008) and (1.005, 1.008), respectively. The kQ for 6X-FFF and 10X-FFF beams (JSDP12, TG-51 addendum) were (0.9950, 0.9947) and (0.9851, 0.9845), respectively. The most effective factor for uncertainty in FFF photon beam measurement was Prp for JSDP12 formalism. Total dosimetric differences between JSDP12 and TG-51 addendum for 6X-FFF and 10X-FFF were -0.47% and -0.73%, respectively. Conclusion: The total dosimetric difference between JSDP12 and TG-51 addendum was within 1%. The introduction of kQ given by JSDP is feasible for FFF photon beam dosimetry. However, we think Prp should be considered for optimal dosimetry procedure even if JSDP12 is used for FFF photon beam dosimetry.

  9. Individual neutron dosimetry

    International Nuclear Information System (INIS)

    Mauricio, C.L.P.

    1987-01-01

    The most important concepts and development in individual neutron dosimetry are presented, especially the dosimetric properties of the albedo technique. The main problem in albedo dosimetry is to calibrate the dosemeter in the environs of each neutron source. Some of the most used calibration techniques are discussed. The IRD albedo dosemeter used in the routine neutron individual monitoring is described in detail. Its dosimetric properties and calibration methods are discussed. (Author) [pt

  10. Radiation processing and high-dose dosimetry at ANSTO

    International Nuclear Information System (INIS)

    Gant, G.J.; Saunders, M.; Banos, C.; Mo, L.; Davies, J.; Evans, O.

    2001-01-01

    The Radiation Technology group at ANSTO is part of the Physics Division and provides services and advice in the areas of gamma irradiation and high-dose dosimetry. ANSTO's irradiation facilities are designed for maximum dose uniformity and provide a precision irradiation service unique in Australia. Radiation Technology makes and sells reference and transfer standard dosimeters which are purchased by users and suppliers of commercial irradiation services in Australia and the Asia-Pacific region. A calibration service is also provided for dosimeters purchased from other suppliers

  11. Comparison of dose response functions for EBT3 model GafChromic™ film dosimetry system.

    Science.gov (United States)

    Aldelaijan, Saad; Devic, Slobodan

    2018-05-01

    Different dose response functions of EBT3 model GafChromic™ film dosimetry system have been compared in terms of sensitivity as well as uncertainty vs. error analysis. We also made an assessment of the necessity of scanning film pieces before and after irradiation. Pieces of EBT3 film model were irradiated to different dose values in Solid Water (SW) phantom. Based on images scanned in both reflection and transmission mode before and after irradiation, twelve different response functions were calculated. For every response function, a reference radiochromic film dosimetry system was established by generating calibration curve and by performing the error vs. uncertainty analysis. Response functions using pixel values from the green channel demonstrated the highest sensitivity in both transmission and reflection mode. All functions were successfully fitted with rational functional form, and provided an overall one-sigma uncertainty of better than 2% for doses above 2 Gy. Use of pre-scanned images to calculate response functions resulted in negligible improvement in dose measurement accuracy. Although reflection scanning mode provides higher sensitivity and could lead to a more widespread use of radiochromic film dosimetry, it has fairly limited dose range and slightly increased uncertainty when compared to transmission scan based response functions. Double-scanning technique, either in transmission or reflection mode, shows negligible improvement in dose accuracy as well as a negligible increase in dose uncertainty. Normalized pixel value of the images scanned in transmission mode shows linear response in a dose range of up to 11 Gy. Copyright © 2018 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  12. A radiochromic film based on leucomalachite green for high-dose dosimetry applications

    International Nuclear Information System (INIS)

    Soliman, Y.S.; Basfar, A.A.; Msalam, R.I.

    2014-01-01

    A colorless polyvinyl butyral film (PVB) based on radiation-sensitive dye of leucomalachite green (LMG) was investigated as a high-dose dosimeter for gamma radiation processing applications in the dose range of 3–150 kGy. The useful applications for such dose range are food irradiation treatment, medical devices sterilization and polymer modification. Gamma irradiation of the film induces a significant intensity of green color, which can be characterized by a main absorption band at 627 nm and a small band at 425 nm. The variation in response of irradiated film stored in the dark and under laboratory light illumination was less than 3% during the first 6 days of storage. The response of film during irradiation was slightly influenced by relative humidity in the range of 12–76%; however, it was significantly affected by temperature in the range of 5–40 °C. The radiation chemical yield was reported to be 6.76 × 10 −6  mol/J at the absorbed dose of 30 kGy for the film containing 6.5% of LMG dye. The overall uncertainty associated with routine dose monitoring would be less than 6% at a 95% confidence level if the dosimeter was being corrected for irradiation conditions and being calibrated with reference standard dosimeter in the production facility. - Highlights: • Development of a radiochromic film based on leucomalachite green dye for radiation processing dosimetry. • The dosimeter useful dose range is 3–150 kGy. • The dosimeter was slightly influenced by humidity levels during irradiation over the range of 12–76%. • The films stored in the dark have a good shelf life with a good stable response after irradiation. • Overall uncertainty of the dosimeter was less than 4.3% at σ

  13. The implementation of in vivo dosimetry in a small radiotherapy department

    International Nuclear Information System (INIS)

    Voordeckers, M.; Goosens, H.; Rutten, J.

    1998-01-01

    In vivo dosimetry has been shown in a number of evaluation studies, generally carried out in larger academic centres, to be a reliable method of checking the overall treatment accuracy. The object of this study was to investigate whether it was possible and useful to perform in vivo dosimetry in a small radiotherapy department and to detect if there were any systematic errors in the overall treatment set-up. All patients were treated on a cobalt-60 unit equipped with a verification system. Six hundred fifty entrance dose measurements were performed with silicon diodes. The analysis showed a mean deviation of -1.3%. This negative deviation was mainly due to the mean deviation obtained in the treatment of head and neck (-1.6%) or breast (-2.5%) cancer patients. The results for pelvic or lung irradiation showed almost no deviation. Further investigation showed that the negative values for head and neck or breast irradiation were due to the irradiation technique, the lack of scattering material causes a reduction of the dose at the reference point, which is not taken into consideration by the treatment planning system. By performing in vivo dosimetry, we were also able to detect two large errors in 650 measurements and could prevent erroneous treatment. Even when the overall treatment set-up is very accurate, in vivo dosimetry is very useful in a small department since only a small effort can detect and prevent errors. (author)

  14. A fiber-dosimetry method based on OSL from Al2O3:C for radiotherapy applications

    International Nuclear Information System (INIS)

    Gaza, R.; McKeever, S.W.S.; Akselrod, M.S.; Akselrod, A.; Underwood, T.; Yoder, C.; Andersen, C.E.; Aznar, M.C.; Marckmann, C.J.; Boetter-Jensen, L.

    2004-01-01

    We describe a high-sensitivity, fiber-optic dosimetry system based on optically stimulated luminescence (OSL) and radioluminescence from Al 2 O 3 :C single-crystal fibers (detectors). The detectors are coupled to a fiber optic delivery system and OSL from the detector is stimulated via the optical fiber cable using light from a Nd:YAG laser. The OSL is guided back along the same fiber and is detected by a photomultiplier tube. The Al 2 O 3 :C detectors are small and demonstrate high sensitivity with a large signal-to-noise ratio. We describe two modes of operation of the system and discuss algorithms that provide accurate estimation of dose rate and integrated dose in near real time. The system is free from magnetic and electrical interference, and is designed for use in several forms of radiotherapy, including in vitro brachytherapy source calibration, and in vivo dosimetry during patient treatment

  15. Absorbed dose determination in external beam radiotherapy. An international code of practice for dosimetry based on standards of absorbed dose to water

    International Nuclear Information System (INIS)

    2000-01-01

    The International Atomic Energy Agency published in 1987 an International Code of Practice entitled 'Absorbed Dose Determination in Photon and Electron Beams' (IAEA Technical Reports Series No. 277 (TRS-277)), recommending procedures to obtain the absorbed dose in water from measurements made with an ionization chamber in external beam radiotherapy. A second edition of TRS-277 was published in 1997 updating the dosimetry of photon beams, mainly kilovoltage X rays. Another International Code of Practice for radiotherapy dosimetry entitled 'The Use of Plane-Parallel Ionization Chambers in High Energy Electron and Photon Beams' (IAEA Technical Reports Series No. 381 (TRS-381)) was published in 1997 to further update TRS-277 and complement it with respect to the area of parallel-plate ionization chambers. Both codes have proven extremely valuable for users involved in the dosimetry of the radiation beams used in radiotherapy. In TRS-277 the calibration of the ionization chambers was based on primary standards of air kerma; this procedure was also used in TRS-381, but the new trend of calibrating ionization chambers directly in a water phantom in terms of absorbed dose to water was introduced. The development of primary standards of absorbed dose to water for high energy photon and electron beams, and improvements in radiation dosimetry concepts, offer the possibility of reducing the uncertainty in the dosimetry of radiotherapy beams. The dosimetry of kilovoltage X rays, as well as that of proton and heavy ion beams, interest in which has grown considerably in recent years, can also be based on these standards. Thus a coherent dosimetry system based on standards of absorbed dose to water is possible for practically all radiotherapy beams. Many Primary Standard Dosimetry Laboratories (PSDLs) already provide calibrations in terms of absorbed dose to water at the radiation quality of 60 Co gamma rays. Some laboratories have extended calibrations to high energy photon and

  16. Accidental and retrospective dosimetry using TL method

    International Nuclear Information System (INIS)

    Mesterházy, D.; Osvay, M.; Kovács, A.; Kelemen, A.

    2012-01-01

    Retrospective dosimetry is one of the most important tools of accidental dosimetry for dose estimation when dose measurement was not planned. In the affected area many objects can be applied as natural dosimeters. The paper discusses our recent investigations on various electronic components and common salt (NaCl) having useful thermoluminescence (TL) properties. Among materials investigated the electronic components of cell phones seem promising for retrospective dosimetry purposes, having high TL responses, proper glow curve peaks and the intensity of TL peaks vs. gamma dose received provided nearly linear response in the dose range of 10 mGy–1.5 Gy. - Highlights: ► Electronic components and common salt were investigated for accidental and retrospective dosimetry. ► SMD resistors seem promising for retrospective dosimetry purposes. ► Table salt can be used effectively for accidental dosimetry purposes, as well.

  17. The importance of BMI in dosimetry of 153Sm-EDTMP bone pain palliation therapy: A Monte Carlo study

    International Nuclear Information System (INIS)

    Fallahpoor, Maryam; Abbasi, Mehrshad; Asghar Parach, Ali; Kalantari, Faraz

    2017-01-01

    Using digital phantoms as an atlas compared to acquiring CT data for internal radionuclide dosimetry decreases patient overall radiation dose and reduces the required analysis effort and time for organ segmentation. The drawback is that the phantom may not match exactly with the patient. We assessed the effect of varying BMIs on dosimetry results for a bone pain palliation agent, 153 Sm-EDTMP. The simulation was done using the GATE Monte Carlo code. Female XCAT phantoms with the following different BMIs were employed: 18.6, 20.8, 22.1, 26.8, 30.3 and 34.7 kg/m 2 . S-factors (mGy/MBq.s) and SAFs (kg −1 ) were calculated for the dosimetry of the radiation from major source organs including spine, ribs, kidney and bladder into different target organs as well as whole body dosimetry from spine. The differences in dose estimates from different phantoms compared to those from the phantom with BMI of 26.8 kg/m 2 as the reference, were calculated for both gamma and beta radiations. The relative differences (RD) of the S-factors or SAFs from the values of reference phantom were calculated. RDs greater than 10% and 100% were frequent in radiations to organs for photon and beta particles, respectively. The relative differences in whole body SAFs from the reference phantom were 15.4%, 7%, 4.2%, −9.8% and −1.4% for BMIs of 18.6, 20.8, 22.1, 30.3 and 34.7 kg/m 2 , respectively. The differences in whole body S-factors for the phantoms with BMIs of 18.6, 20.8, 22.1, 30.3 and 34.7 kg/m 2 were 39.5%, 19.4%, 8.8%, −7.9% and −4.3%, respectively. The dosimetry of the gamma photons and beta particles changes substantially with the use of phantoms with different BMIs. The change in S-factors is important for dose calculation and can change the prescribed therapeutic dose of 153 Sm-EDTMP. Thus a phantom with BMI better matched to the patient is suggested for therapeutic purposes where dose estimates closer to those in the actual patient are required. - Highlights: • Internal

  18. Development and clinical application of In Vivo dosimetry for radiotherapy

    International Nuclear Information System (INIS)

    Honda, Hirofumi; Oita, Masataka; Tominaga, Masahide; Oto, Yoshihiro

    2016-01-01

    In practical radiotherapy, it is important to deliver radiation to the target correctly and safely according to the treatment planning. The control of radiation dose delivered to each patient in radiotherapy mainly relies on the prediction based on the result of pre-treatment verification and irradiation accuracy of treatment machines. In Vivo dosimetry in radiotherapy is the procedure of quality assurance by the way of direct measurement for the patient whether the calculated prescribed dose in the treatment planning is delivered precisely. The history of In Vivo dosimetry is relatively long, and the TLD dosimetry for clinical radiotherapy started in early 1970's. After 1980's, owing to the development of semiconductor devices such as diode detectors, semiconductor arrays, the clinical applications for the dosimetry and diagnostic radiation imaging devices which contributed to the development of electric portal imaging devices and 2D semiconductor detectors were introduced. In recent years, these radiation measurement devices and non-invasive methods have been developed, they are becoming widespread as clinical practice. In this paper, we reviewed the In Vivo dosimetry devices and their characteristics, and technical application for radiotherapy. (author)

  19. The sixth EULEP x-ray dosimetry intercomparison

    International Nuclear Information System (INIS)

    Aalbers, A.H.L.; Bader, F.J.M.

    1991-03-01

    During march-October 1989, the 6th EULEP X-Ray Dosimetry Inter-comparison on whole-body irradiation of mice was performed. It consisted of 2 irradiation series; the initial study comprised 15 participating institutes, the 2nd series was performed for 7 institutes which showed appreciable deviation from reference value. Mouse phantoms containing LiF:Mg,Ti thermoluminescent dosemeters (TLD-100 extruded ribbons) were mailed to participating institutes. In accordance with EULEP Protocol recommendations, participants performed irradiations using a procedure whereby the mouse phantom should receive an absorbed dose of 2Gy in muscle tissue at the central position. The read-out and evaluation of TL-dosemeters was performed at Dutch National Institute of Public Health and Environmental Protection (RIVM Bilthoven). The mean absorbed dose results in the centre of the phantom revealed that 10/15 participants agreed with the reference institute to within 5%. Somewhat larger deviations (±5-10%) were observed for 3 participants The remaining 2 participants showed discrepancies up to 15%. Uniform dose distributions over the mouse phantoms i.e. dose variations of ≤ 10% were observed for 10 participants. Four participants did not meet the recommended criterion for a uniform dose distribution, and one did not aim for uniform exposure conditions. Procedures followed to assess the comparability of dosimetry at different institutes cooperating within EULEP, are satisfactory with regard to the determination of absorbed dose and dose distribution. The deviations observed at 5 institutes indicate the need for site-visits to trace probable systematic errors. (author). 9 refs.; 10 figs.; 6 tabs

  20. Optically stimulated luminescence in retrospective dosimetry

    International Nuclear Information System (INIS)

    Boetter-Jensen, L.; Murray, A.S.

    2002-01-01

    Since the beginning of the 1990s the exploration of optically stimulated luminescence in retrospective accident dosimetry has driven an intensive investigation and development programme at Ris deg. into measurement facilities and techniques. This paper reviews some of the outcomes of this programme, including the evaluation of the single-aliquot regenerative-dose measurement protocol with brick quartz and the determination of dose-depth profiles in building materials as a guide to determining the mean energy of the incident radiation. Investigations into heated materials are most advanced, and a lower detection limit for quartz extracted from Chernobyl bricks was determined to be <10 mGy. The first results from the measurement of doses in unheated building materials such as mortar and concrete are also discussed. Both small-aliquot and single-grain techniques have been used to assess accident doses in these cement based building materials more commonly found in workplaces. Finally some results of a preliminary investigation of the OSL properties of household chemicals are discussed with reference to their potential as accident dosemeters. (author)

  1. Radiation dosimetry estimates of "1"8F-alfatide II based on whole-body PET imaging of mice

    International Nuclear Information System (INIS)

    Wang, Si-yang; Bao, Xiao; Wang, Ming-wei; Zhang, Yong-ping; Zhang, Ying-jian; Zhang, Jian-ping

    2015-01-01

    We estimated the dosimetry of "1"8F-alfatide II with the method established by MIRD based on biodistribution data of mice. Six mice (three females and three males) were scanned for 160 min on an Inveon MicroPET/CT scanner after injection of "1"8F-alfatide II via tail vein. Eight source organs were delineated on the CT images and their residence times calculated. The data was then converted to human using scaling factors based on organ and body weight. The absorbed doses for human and the resulting effective dose were computed by OLINDA 1.1 software. The highest absorbed doses was observed in urinary bladder wall (male 0.102 mGy/MBq, female 0.147 mGy/MBq); and the lowest one was detected in brain (male 0.0030 mGy/MBq, female 0.0036). The total effective doses were 0.0127 mSv/MBq for male and 0.0166 mSv/MBq for female, respectively. A 370-MBq injection of "1"8F-alfatide II led to an estimated effective dose of 4.70 mSv for male and 6.14 mSv for female. The potential radiation burden associated with "1"8F-alfatide II/PET imaging therefore is comparable to other PET examinations. - Highlights: • We demonstrated a proper mice model to estimate human radiation dosimetry. • This is the first paper to estimate human radiation dosimetry of "1"8F-alfatide II. • Estimated effective dose are in the range of routine nuclear medicine studies.

  2. Dosimetry and Calibration Section

    International Nuclear Information System (INIS)

    Otto, T.

    1998-01-01

    The two tasks of the Dosimetry and Calibration Section at CERN are the Individual Dosimetry Service which assures the personal monitoring of about 5000 persons potentially exposed to ionizing radiation at CERN, and the Calibration Laboratory which verifies all the instruments and monitors. This equipment is used by the sections of the RP Group for assuring radiation protection around CERN's accelerators, and by the Environmental Section of TISTE. In addition, nearly 250 electronic and 300 quartz fibre dosimeters, employed in operational dosimetry, are calibrated at least once a year. The Individual Dosimetry Service uses an extended database (INDOS) which contains information about all the individual doses ever received at CERN. For most of 1997 it was operated without the support of a database administrator as the technician who had assured this work retired. The Software Support Section of TIS-TE took over the technical responsibility of the database, but in view of the many other tasks of this Section and the lack of personnel, only a few interventions for solving immediate problems were possible

  3. Practice for use of a ceric-cerous sulfate dosimetry system

    International Nuclear Information System (INIS)

    2002-01-01

    This practice covers the preparation, testing, and procedure for using the ceric-cerous sulfate dosimetry system to measure absorbed dose in water when exposed to ionizing radiation. The system consists of a dosimeter and appropriate analytical instrumentation. For simplicity, the system will be referred to as the ceric-cerous system. It is classified as a reference standard dosimetry system (see ISO/ASTM Guide 51261). Ceric-cerous dosimeters are also used as transfer-standard dosimeters or routine dosimeters. This practice describes both the spectrophotometric and the potentiometric readout procedures for the ceric-cerous systems. This practice applies only to g rays, X rays, and high energy electrons. This practice applies provided the following are satisfied: The absorbed-dose range shall be between 5x10 2 and 5x10 4 Gy. The absorbed-dose rate shall be less than 10 6 Gy/s. For radionuclide gamma-ray sources, the initial photon energy shall be greater than 0.6 MeV. For bremsstrahlung photons, the initial energy of the electrons used to produce the bremsstrahlung photons shall be equal to or greater than 2 MeV. For electron beams, the initial electron energy shall be greater than 8 MeV. The irradiation temperature of the dosimeter shall be between 0 and 62 deg C

  4. Individualized adjustments to reference phantom internal organ dosimetry-scaling factors given knowledge of patient external anatomy.

    Science.gov (United States)

    Wayson, Michael B; Bolch, Wesley E

    2018-04-13

    Internal radiation dose estimates for diagnostic nuclear medicine procedures are typically calculated for a reference individual. Resultantly, there is uncertainty when determining the organ doses to patients who are not at 50th percentile on either height or weight. This study aims to better personalize internal radiation dose estimates for individual patients by modifying the dose estimates calculated for reference individuals based on easily obtainable morphometric characteristics of the patient. Phantoms of different sitting heights and waist circumferences were constructed based on computational reference phantoms for the newborn, 10 year-old, and adult. Monoenergetic photons and electrons were then simulated separately at 15 energies. Photon and electron specific absorbed fractions (SAFs) were computed for the newly constructed non-reference phantoms and compared to SAFs previously generated for the age-matched reference phantoms. Differences in SAFs were correlated to changes in sitting height and waist circumference to develop scaling factors that could be applied to reference SAFs as morphometry corrections. A further set of arbitrary non-reference phantoms were then constructed and used in validation studies for the SAF scaling factors. Both photon and electron dose scaling methods were found to increase average accuracy when sitting height was used as the scaling parameter (~11%). Photon waist circumference-based scaling factors showed modest increases in average accuracy (~7%) for underweight individuals, but not for overweight individuals. Electron waist circumference-based scaling factors did not show increases in average accuracy. When sitting height and waist circumference scaling factors were combined, modest average gains in accuracy were observed for photons (~6%), but not for electrons. Both photon and electron absorbed doses are more reliably scaled using scaling factors computed in this study. They can be effectively scaled using sitting

  5. Dosimetry of Al2O3 optically stimulated luminescent dosimeter at high energy photons and electrons

    Science.gov (United States)

    Yusof, M. F. Mohd; Joohari, N. A.; Abdullah, R.; Shukor, N. S. Abd; Kadir, A. B. Abd; Isa, N. Mohd

    2018-01-01

    The linearity of Al2O3 OSL dosimeters (OSLD) were evaluated for dosimetry works in clinical photons and electrons. The measurements were made at a reference depth of Zref according to IAEA TRS 398:2000 codes of practice at 6 and 10 MV photons and 6 and 9 MeV electrons. The measured dose was compared to the thermoluminescence dosimeters (TLD) and ionization chamber commonly used for dosimetry works for higher energy photons and electrons. The results showed that the measured dose in OSL dosimeters were in good agreement with the reported by the ionization chamber in both high energy photons and electrons. A reproducibility test also reported excellent consistency of readings with the OSL at similar energy levels. The overall results confirmed the suitability of OSL dosimeters for dosimetry works involving high energy photons and electrons in radiotherapy.

  6. Revisiting photodynamic therapy dosimetry: reductionist & surrogate approaches to facilitate clinical success

    Science.gov (United States)

    Pogue, Brian W.; Elliott, Jonathan T.; Kanick, Stephen C.; Davis, Scott C.; Samkoe, Kimberley S.; Maytin, Edward V.; Pereira, Stephen P.; Hasan, Tayyaba

    2016-04-01

    Photodynamic therapy (PDT) can be a highly complex treatment, with many parameters influencing treatment efficacy. The extent to which dosimetry is used to monitor and standardize treatment delivery varies widely, ranging from measurement of a single surrogate marker to comprehensive approaches that aim to measure or estimate as many relevant parameters as possible. Today, most clinical PDT treatments are still administered with little more than application of a prescribed drug dose and timed light delivery, and thus the role of patient-specific dosimetry has not reached widespread clinical adoption. This disconnect is at least partly due to the inherent conflict between the need to measure and understand multiple parameters in vivo in order to optimize treatment, and the need for expedience in the clinic and in the regulatory and commercialization process. Thus, a methodical approach to selecting primary dosimetry metrics is required at each stage of translation of a treatment procedure, moving from complex measurements to understand PDT mechanisms in pre-clinical and early phase I trials, towards the identification and application of essential dose-limiting and/or surrogate measurements in phase II/III trials. If successful, identifying the essential and/or reliable surrogate dosimetry measurements should help facilitate increased adoption of clinical PDT. In this paper, examples of essential dosimetry points and surrogate dosimetry tools that may be implemented in phase II/III trials are discussed. For example, the treatment efficacy as limited by light penetration in interstitial PDT may be predicted by the amount of contrast uptake in CT, and so this could be utilized as a surrogate dosimetry measurement to prescribe light doses based upon pre-treatment contrast. Success of clinical ALA-based skin lesion treatment is predicted almost uniquely by the explicit or implicit measurements of photosensitizer and photobleaching, yet the individualization of treatment

  7. Neutron personal dosimetry: state-of-art

    International Nuclear Information System (INIS)

    Spurný, František

    2005-03-01

    State-of-art of the personal neutron dosimetry is presented, analysed and discussed. Particular attention is devoted to the problems of this type of the dosimetry of external exposure for radiation fields at nuclear power plants. A review of general problems of neutron dosimetry is given and the active individual dosimetry methods available and/or in the stage of development are briefly reviewed. Main attention is devoted to the analysis of the methods available for passive individual neutron dosimetry. The characteristics of these dosemeters were studied and are compared: their energy response functions, detection thresholds and the highest detection limits, the linearity of response, the influence of environmental factors, etc. Particular attention is devoted to their behavior in reactor neutron fields. It is concluded that the choice of the neutron personal dosemeter depends largely on the conditions in which the instrument should be used (neutron spectrum, the level of exposure and the exposure rate, etc.). The results obtained with some of these dosemeters during international intercomparisons are also presented. Particular attention is paid to the personal neutron dosimeter developed and routinely used by National Personal Dosimetry Service Ltd. in the Czech Republic. (author)

  8. NURBS-based 3-d anthropomorphic computational phantoms for radiation dosimetry applications

    International Nuclear Information System (INIS)

    Lee, Choonsik; Lodwick, Daniel; Lee, Choonik; Bolch, Wesley E.

    2007-01-01

    Computational anthropomorphic phantoms are computer models used in the evaluation of absorbed dose distributions within the human body. Currently, two classes of the computational phantoms have been developed and widely utilised for dosimetry calculation: (1) stylized (equation-based) and (2) voxel (image-based) phantoms describing human anatomy through the use of mathematical surface equations and 3-D voxel matrices, respectively. However, stylized phantoms have limitations in defining realistic organ contours and positioning as compared to voxel phantoms, which are themselves based on medical images of human subjects. In turn, voxel phantoms that have been developed through medical image segmentation have limitations in describing organs that are presented in low contrast within either magnetic resonance or computed tomography image. The present paper reviews the advantages and disadvantages of these existing classes of computational phantoms and introduces a hybrid approach to a computational phantom construction based on non-uniform rational B-Spline (NURBS) surface animation technology that takes advantage of the most desirable features of the former two phantom types. (authors)

  9. Application of MOS structures to gamma dosimetry

    International Nuclear Information System (INIS)

    Frank, H.

    1978-01-01

    Lattice disorders induced in SiO 2 layers by irradiation are described, and the possibility of using MOS transistors for gamma dosimetry is discussed. Furthermore, experimental results are given for Czechoslovakian MOS transistors of MH 2009 type after gamma irradiation. Reference measurements with other irradiation sources have shown that the transistors respond only to those types of radiation which induce space charges in the oxide layer. They are, therefore, insensitive to neutrons and thus in contrast to dosimetric silicon diodes. Circuitry, sensitivity, and fading of MOS transistors are given, and a physical functional model is compared with the experimental results. (author)

  10. An investigation of the photon energy dependence of the EPR alanine dosimetry system

    International Nuclear Information System (INIS)

    Bergstrand, Eva Stabell; Shortt, Ken R; Ross, Carl K; Hole, Eli Olaug

    2003-01-01

    The electron paramagnetic resonance (EPR) alanine dosimetry system is based on EPR measurements of radicals formed in alanine by ionizing radiation. The system has been studied to determine its energy dependence for photons in the 10-30 MV region relative to those of 60 Co and to find out if the system would be suitable for dosimetry comparisons. The irradiations were carried out at the National Research Council, Ottawa, Canada and the doses ranged from 8 to 54 Gy. The EPR measurements were performed at the University of Oslo, Norway. The ratio of the slope of the alanine reading versus dose-to-water curve for a certain linac photon beam quality and the corresponding slope for a reference 60 Co γ-radiation gives an experimental measure of the relative dose-to-water response of the EPR alanine dosimetry system. For calculating the linear regression coefficients of these alanine reading versus dose curves, the method of weighted least squares was used. This method is assumed to produce more accurate regression coefficients when applied to EPR dosimetry than the common method of standard least squares. The overall uncertainty on the ratio of slopes was between 0.5 and 0.6% for all three linac energies. The relative response for all the linac beams compared to cobalt was less than unity: by about 0.5% for the 20 and 30 MV points but by more than 1% for the 10 MV point. The given standard uncertainties negate concluding that there is any significant internal variation in the measured response as a function of beam quality between the three linac energies. Thus, we calculated the average dose response for all three energies and found that the alanine response is 0.8% (±0.5%) lower for high energy x-rays than for 60 Co γ-rays. This result indicates a small energy dependence in the alanine response for the high-energy photons relative to 60 Co which may be significant. This result is specific to our dosimetry system (alanine with 20% polyethylene binder pressed into a

  11. Evaluation of Dosimetry Check software for IMRT patient-specific quality assurance.

    Science.gov (United States)

    Narayanasamy, Ganesh; Zalman, Travis; Ha, Chul S; Papanikolaou, Niko; Stathakis, Sotirios

    2015-05-08

    The purpose of this study is to evaluate the use of the Dosimetry Check system for patient-specific IMRT QA. Typical QA methods measure the dose in an array dosimeter surrounded by homogenous medium for which the treatment plan has been recomputed. With the Dosimetry Check system, fluence measurements acquired on a portal dosimeter is applied to the patient's CT scans. Instead of making dose comparisons in a plane, Dosimetry Check system produces isodose lines and dose-volume histograms based on the planning CT images. By exporting the dose distribution from the treatment planning system into the Dosimetry Check system, one is able to make a direct comparison between the calculated dose and the planned dose. The versatility of the software is evaluated with respect to the two IMRT techniques - step and shoot and volumetric arc therapy. The system analyzed measurements made using EPID, PTW seven29, and IBA MatriXX, and an intercomparison study was performed. Plans from patients previously treated at our institution with treated anatomical site on brain, head & neck, liver, lung, and prostate were analyzed using Dosimetry Check system for any anatomical site dependence. We have recommendations and possible precautions that may be necessary to ensure proper QA with the Dosimetry Check system.

  12. Internal dosimetry technical basis manual

    International Nuclear Information System (INIS)

    1990-01-01

    The internal dosimetry program at the Savannah River Site (SRS) consists of radiation protection programs and activities used to detect and evaluate intakes of radioactive material by radiation workers. Examples of such programs are: air monitoring; surface contamination monitoring; personal contamination surveys; radiobioassay; and dose assessment. The objectives of the internal dosimetry program are to demonstrate that the workplace is under control and that workers are not being exposed to radioactive material, and to detect and assess inadvertent intakes in the workplace. The Savannah River Site Internal Dosimetry Technical Basis Manual (TBM) is intended to provide a technical and philosophical discussion of the radiobioassay and dose assessment aspects of the internal dosimetry program. Detailed information on air, surface, and personal contamination surveillance programs is not given in this manual except for how these programs interface with routine and special bioassay programs

  13. Internal dosimetry technical basis manual

    Energy Technology Data Exchange (ETDEWEB)

    1990-12-20

    The internal dosimetry program at the Savannah River Site (SRS) consists of radiation protection programs and activities used to detect and evaluate intakes of radioactive material by radiation workers. Examples of such programs are: air monitoring; surface contamination monitoring; personal contamination surveys; radiobioassay; and dose assessment. The objectives of the internal dosimetry program are to demonstrate that the workplace is under control and that workers are not being exposed to radioactive material, and to detect and assess inadvertent intakes in the workplace. The Savannah River Site Internal Dosimetry Technical Basis Manual (TBM) is intended to provide a technical and philosophical discussion of the radiobioassay and dose assessment aspects of the internal dosimetry program. Detailed information on air, surface, and personal contamination surveillance programs is not given in this manual except for how these programs interface with routine and special bioassay programs.

  14. Dosimetry systems for radiation processing

    International Nuclear Information System (INIS)

    McLaughlin, W.L.; Desrosiers, M.F.

    1995-01-01

    Dosimetry serves important functions in radiation processing, where large absorbed doses and dose rates from photon and electron sources have to be measured with reasonable accuracy. Proven dosimetry systems are widely used to perform radiation measurements in development of new processes, validation, qualification and verification (quality control) of established processes and archival documentation of day-to-day and plant-to-plant processing uniformity. Proper calibration and traceability of routine dosimetry systems to standards are crucial to the success of many large-volume radiation processes. Recent innovations and advances in performance of systems that enhance radiation measurement assurance and process diagnostics include dose-mapping media (new radiochromic film and solutions), optical waveguide systems for food irradiation, solid-state devices for real-time and passive dosimetry over wide dose-rate and dose ranges, and improved analytical instruments and data acquisition. (author)

  15. Information from the Dosimetry Service

    CERN Multimedia

    2006-01-01

    Please note the following opening hours of the Service: From 31st July onwards: Every morning from 8:30 to 12:00 The Service is closed in the afternoons. We should like to remind you that dosimeters cannot be sent to customers by internal mail. Short-term dosimeters (VCTs) must always be returned to the Service after use and must not be left on the racks in the experimental areas or in the secretariats. Dosimetry Service Tel 72155 Bldg. 24 E 011 Dosimetry.service@cern.ch http://cern.ch/rp-dosimetry

  16. Relationship between student selection criteria and learner success for medical dosimetry students.

    Science.gov (United States)

    Baker, Jamie; Tucker, Debra; Raynes, Edilberto; Aitken, Florence; Allen, Pamela

    2016-01-01

    Medical dosimetry education occupies a specialized branch of allied health higher education. Noted international shortages of health care workers, reduced university funding, limitations on faculty staffing, trends in learner attrition, and increased enrollment of nontraditional students force medical dosimetry educational leadership to reevaluate current admission practices. Program officials wish to select medical dosimetry students with the best chances of successful graduation. The purpose of the quantitative ex post facto correlation study was to investigate the relationship between applicant characteristics (cumulative undergraduate grade point average (GPA), science grade point average (SGPA), prior experience as a radiation therapist, and previous academic degrees) and the successful completion of a medical dosimetry program, as measured by graduation. A key finding from the quantitative study was the statistically significant positive correlation between a student׳s previous degree and his or her successful graduation from the medical dosimetry program. Future research investigations could include a larger research sample, representative of more medical dosimetry student populations, and additional studies concerning the relationship of previous work as a radiation therapist and the effect on success as a medical dosimetry student. Based on the quantitative correlation analysis, medical dosimetry leadership on admissions committees could revise student selection rubrics to place less emphasis on an applicant׳s undergraduate cumulative GPA and increase the weight assigned to previous degrees. Copyright © 2016 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.

  17. Developing a high performance superoxide dismutase based electrochemical biosensor for radiation dosimetry of thallium 201

    International Nuclear Information System (INIS)

    Salem, Fatemeh; Tavakoli, Hassan; Sadeghi, Mahdi; Riazi, Abbas

    2014-01-01

    To develop a new biosensor for measurement of superoxide free radical generated in radiolysis reaction, three combinations of SOD-based biosensors including Au/Cys/SOD, Au/GNP/Cys/SOD and Au/GNP/Cys/SOD/Chit were fabricated. In these biosensors Au, GNP, Cys, SOD and Chit represent gold electrode, gold nano-particles, cysteine, superoxide dismutase and chitosan, respectively. For biosensors fabrication, SOD, GNP, Cys and Chit were immobilized at the surface of gold electrode. Cyclic voltametry and chronoamperometry were utilized for evaluation of biosensors performances. The results showed that Au/GNP/Cys/SOD/Chit has significantly better responses compared to Au/Cys/SOD and Au/GNP/Cys/SOD. As a result, this biosensor was selected for dosimetry of ionizing radiation. For this purpose, thallium 201 at different volumes was added to buffer phosphate solution in electrochemical cell. To obtain analytical parameters of Au/GNP/Cys/SOD/Chit, calibration curve was sketched. The results showed that this biosensor has a linear response in the range from 0.5 to 4 Gy, detection limit 0.03 μM. It also has a proper sensitivity (0.6038 nA/Gy), suitable long term stability and cost effective as well as high function for radiation dosimetry. - highlights: • Our biosensor is able to measure produced superoxide radical during water radiolysis. • It has suitable linearity range, good detection limit and long term stability. • It also has proper sensitivity and high performance for low LET ionizing radiation. • The electrochemical method is as good as traditional methods for radiation dosimetry

  18. High-accuracy dosimetry study for intensity-modulated radiation therapy(IMRT) commissioning

    International Nuclear Information System (INIS)

    Jeong, Hae Sun

    2010-02-01

    .5 cm 2 ). In addition, a method using a pixel-based unfolding curve was developed and applied to correct the non-uniform response of flat-bed type scanners for a radiochromic film. Also, the accuracy of the method was finally evaluated by comparing the results with those of an ion chamber, Monte Carlo simulation, and CF-based conventional method. For individual dose, the dosimetric error of using conventional method and using the pixel-based unfolding curve was reduced to less than 3%, and 1%, respectively. In case of step-wise doses, the average difference of 16% with MC calculation was reduced up to 1% by using the correction method in this study. Consequently, the accuracy of dose computation algorithms in TPS can be evaluated by the developed LEGO-type solid phantom, small filed dosimetry, the correction method for non-uniform response of scanners. It is also recognized that the developed hardware and software which are possible to be used for QA procedure are very reliable and they could be used for reference study of other radiation therapies

  19. In vivo dosimetry in radiation therapy in Sweden; In vivo-dosimetri inom straalbehandling i Sverige

    Energy Technology Data Exchange (ETDEWEB)

    Eriksson, Jacob; Blomquist, Michael (Norrlands universitetssjukhus, Umeaa (Sweden))

    2010-07-15

    A prerequisite for achieving high radiation safety for patients receiving external beam radiation therapy is that the hospitals have a quality assurance program. The program should include include monitoring of the radiation dose given to the patient. Control measurements are performed both at the system level and at the individual level. Control measurement is normally performed using in vivo dosimetry, e.g. a method to measure the radiation dose at the individual level during the actual radiation treatment time. In vivo dosimetry has proven to be an important tool to detect and prevent serious errors in patient treatment. The purpose of this research project was to identify the extent to which vivo dosimetry is used and the methods available for this at Swedish radiation therapy clinics. The authority also wanted to get an overall picture of how hospitals manage results of in vivo dosimetry, and how clinics control radiation dose when using modern treatment techniques. The report reflects the situation in Swedish radiotherapy clinics 2007. The report shows that all hospitals use some form of in vivo dosimetry. The instruments used are mainly diodes and termoluminiscence dosimeters

  20. Course of training in Specific internal dosimetry for the patient

    International Nuclear Information System (INIS)

    Rojo, A.M.; Michelin, S.C.; Gomez P, I.M.

    2006-01-01

    In this work the experience obtained in a course organized in Argentina to qualify professionals in the radiopharmaceutical dosimetry using the methodology MIRD and the patient's images is presented. The motivation to carry out it was based on the continuous development of new radiopharmaceuticals with therapeutic purposes that makes necessary the knowledge of the distribution of the absorbed dose to be able to establish the dose-response relationship. The main objective was the study of the biokinetic model and those techniques available that starting from images can contribute information of specific parameters of the patient to calculate with more accuracy the doses in the tumor and in different organs. In the design of the program of this course it was considered to approach the different focuses for the calculation of specific dose of the patient and includes the following topics: the patient's radiological protection, new concepts in damages by radiations (bystander effect), methodology for the internal dosimetry by radiopharmaceuticals, dosimetric systems (MIRD/ICRP), revision of the physical phantoms, design of kinetic studies, compartmental models, calculation tools and the demonstration of the programs SAAM and OLINDA; calculation of activity starting from the patient's images (planar and SPECT). Principles of the gamma camera: the dispersed radiation, calculation of the activity with planar images, the attenuation, correction of the dispersed radiation, collimation problems. SPECT: the common method of reconstruction, basic principles, method of filtered over head projection and iterative methods (MLEM/OSEM), measurement of the attenuation maps, problems of the penetration in the collimator (I-131, I-123), effects of partial volume, incorporation of corrections in an iterative reconstruction. Dosimetry in bone marrow, discussion of study cases of new radiopharmaceuticals. Internal dosimetry in small scale for electrons and photons. Perspectives of the

  1. Patient dosimetry workshop - Scanner in clinical practice: how to optimize one's protocols (acquisition, interpretation, dosimetry)? - Radiation protection in medical environment

    International Nuclear Information System (INIS)

    Valero, M.; Pilleul, F.; Favre, F.; Tack, D.; Etard, C.; Aubert, B.; Roch, P.; Sinno-Tellier, S.; Gevenois, P.A.; Marelle, P.; Noel, A.; Coquel, P.; Museux, E.; Lair, F.; Francois, A.; Lemaire, P.; Delgoffe, C.; Puech, J.L.; Haller Montejo, M.; Rousselle, I.; Noel, A.; Pierrat, N.; Lasalle, S.; Brisse, H.; Guerson, T.; Mertz, L.; Mertz, M.; Wasylczenko, T.; Bietry, J.; Notter, S.; Jahnen, A.; Back, C.; Kohler, S.; Harpes, N.

    2010-01-01

    A selection of eleven brief communications given at the 2010 French days of radiology are compiled here and deal with: 1 - patient's dosimetry in classical radiology (Valero, M.); 2 - Oncology: how to optimize monitoring (dosimetry, new response criteria)? (Pilleul, F.; Favre, F.); 3 - Thorax: how to optimize lecture (MPR - Multi-Planar Reformat, MIP - Maximum Intensity Projection, MinIP - minimum intensity projection) and dosimetry? (Braine-L'Alleud); 4 - Medical exposure of the French population to diagnostic techniques in 2007 (Etard, C.; Aubert, B.; Sinno-Tellier, S.); 5 - Doses delivered to patients in radio-diagnostics: status of a national inquiry in the public sector (Etard, C.; Sinno-Tellier, S.; Aubert, B.); 6 - External help for the dose per section optimization in tomodensitometry (Tack, D.; Jahnen, A.; Back, C.; Kohler, S.; Harpes, N.; Gevenois, P.A.); 7 - Diagnostic reference levels (DRL) in radiology and scanography: status and evolution (Roch, P.; Aubert, B.); 8 - What conclusions can be drawn from the analysis of the DRLs in conventional radiology addressed to the CEPPIM (College for the evaluation of professional practices in medical imaging) (Marelle, P.; Coquel, P.; Museux, E.; Lair, F.; Francois, A.; Lemaire, P.; Delgoffe, C.; Puech, J.L.; Haller Montejo, M.); 9 - DRL analysis in scanography, an optimization tool? (Rousselle, I.; Noel, A.); 10 - Iterative reconstruction in scanography: potential dosimetric benefit and impact on image quality (Pierrat, N.; Lasalle, S.; Guerson, T.; Brisse, H.); 11 - Development of a patient's dose optimisation aided system in medical imaging (Mertz, L.; Mertz, M.; Wasylczenko, T.; Bietry, J.; Notter, S.)

  2. The Latin American Biological Dosimetry Network (LBDNet).

    Science.gov (United States)

    García, O; Di Giorgio, M; Radl, A; Taja, M R; Sapienza, C E; Deminge, M M; Fernández Rearte, J; Stuck Oliveira, M; Valdivia, P; Lamadrid, A I; González, J E; Romero, I; Mandina, T; Guerrero-Carbajal, C; ArceoMaldonado, C; Cortina Ramírez, G E; Espinoza, M; Martínez-López, W; Di Tomasso, M

    2016-09-01

    Biological Dosimetry is a necessary support for national radiation protection programmes and emergency response schemes. The Latin American Biological Dosimetry Network (LBDNet) was formally founded in 2007 to provide early biological dosimetry assistance in case of radiation emergencies in the Latin American Region. Here are presented the main topics considered in the foundational document of the network, which comprise: mission, partners, concept of operation, including the mechanism to request support for biological dosimetry assistance in the region, and the network capabilities. The process for network activation and the role of the coordinating laboratory during biological dosimetry emergency response is also presented. This information is preceded by historical remarks on biological dosimetry cooperation in Latin America. A summary of the main experimental and practical results already obtained by the LBDNet is also included. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. Dosimetry audits and intercomparisons in radiotherapy: A Malaysian profile

    Science.gov (United States)

    M. Noor, Noramaliza; Nisbet, A.; Hussein, M.; Chu S, Sarene; Kadni, T.; Abdullah, N.; Bradley, D. A.

    2017-11-01

    Quality audits and intercomparisons are important in ensuring control of processes in any system of endeavour. Present interest is in control of dosimetry in teletherapy, there being a need to assess the extent to which there is consistent radiation dose delivery to the patient. In this study we review significant factors that impact upon radiotherapy dosimetry, focusing upon the example situation of radiotherapy delivery in Malaysia, examining existing literature in support of such efforts. A number of recommendations are made to provide for increased quality assurance and control. In addition to this study, the first level of intercomparison audit i.e. measuring beam output under reference conditions at eight selected Malaysian radiotherapy centres is checked; use being made of 9 μm core diameter Ge-doped silica fibres (Ge-9 μm). The results of Malaysian Secondary Standard Dosimetry Laboratory (SSDL) participation in the IAEA/WHO TLD postal dose audit services during the period between 2011 and 2015 will also been discussed. In conclusion, following review of the development of dosimetry audits and the conduct of one such exercise in Malaysia, it is apparent that regular periodic radiotherapy audits and intercomparison programmes should be strongly supported and implemented worldwide. The programmes to-date demonstrate these to be a good indicator of errors and of consistency between centres. A total of ei+ght beams have been checked in eight Malaysian radiotherapy centres. One out of the eight beams checked produced an unacceptable deviation; this was found to be due to unfamiliarity with the irradiation procedures. Prior to a repeat measurement, the mean ratio of measured to quoted dose was found to be 0.99 with standard deviation of 3%. Subsequent to the repeat measurement, the mean distribution was 1.00, and the standard deviation was 1.3%.

  4. Dosimetry control for radiation processing - basic requirements and standards

    International Nuclear Information System (INIS)

    Ivanova, M.; Tsrunchev, Ts.

    2004-01-01

    A brief review of the basic international codes and standards for dosimetry control for radiation processing (high doses dosimetry), setting up a dosimetry control for radiation processing and metrology control of the dosimetry system is made. The present state of dosimetry control for food processing and the Bulgarian long experience in food irradiation (three irradiation facilities are operational at these moment) are presented. The absence of neither national standard for high doses nor accredited laboratory for calibration and audit of radiation processing dosimetry systems is also discussed

  5. Annual course of retraining for the occupational exposure personnel of the laboratory of internal dosimetry

    International Nuclear Information System (INIS)

    Alfaro L, M.M.

    2002-09-01

    The general objective of this report is to instruct the personnel in the basic concepts of radiological protection and in the Manual of Procedures of Radiological Safety of the Laboratory of Internal Dosimetry. Also, to exchange experiences during the activities that are carried out in the laboratory and in the knowledge of abnormal situations. The referred Manual consists of 14 procedures and 5 instructions which are listed in annex of this document. The content of this course consists of three topics: 1. Basic principles of radiological protection to reduce the received dose equivalent. 2. Use of radiation measurer equipment. 3. Emergency procedures of the laboratory of internal dosimetry. (Author)

  6. SU-F-BRA-11: An Experimental Commissioning Test of Brachytherapy MBDCA Dosimetry, Based On a Commercial Radiochromic Gel/optical CT System

    Energy Technology Data Exchange (ETDEWEB)

    Pappas, E; Karaiskos, P; Zourari, K; Peppa, V; Papagiannis, P [Medical Physics Laboratory, Medical School, University of Athens (Greece)

    2015-06-15

    Purpose: To implement a 3D dose verification procedure of Model-Based Dose Calculation Algorithms (MBDCAs) for {sup 192}Ir HDR brachytherapy, based on a novel Ferrous Xylenol-orange gel (FXG) and optical CT read-out. Methods: The TruView gel was employed for absolute dosimetry in conjunction with cone-beam optical CT read-out with the VISTA scanner (both from Modus Medical Inc, London, ON, Canada). A multi-catheter skin flap was attached to a cylindrical PETE jar (d=9.6cm, h=16cm) filled with FXG, which served as both the dosimeter and the water equivalent phantom of bounded dimensions. X- ray CT image series of the jar with flap attached was imported to Oncentra Brachy v.4.5. A treatment plan consisting of 8 catheters and 56 dwell positions was generated, and Oncentra-ACE MBDCA as well as TG43 dose results were exported for further evaluation. The irradiation was carried out with a microSelecton v2 source. The FXG dose-response, measured via an electron irradiation of a second dosimeter from the same batch, was linear (R2>0.999) at least up to 12Gy. A MCNP6 input file was prepared from the DICOM-RT plan data using BrachyGuide to facilitate Monte Carlo (MC) simulation dosimetry in the actual experimental geometry. Agreement between experimental (reference) and calculated dose distributions was evaluated using the 3D gamma index (GI) method with criteria (5%-2mm applied locally) determined from uncertainty analysis. Results: The TG-43 GI failed, as expected, in the majority of voxels away from the flap (pass rate 59% for D>0.8Gy, corresponding to 10% of prescribed dose). ACE performed significantly better (corresponding pass rate 92%). The GI evaluation for the MC data (corresponding pass rate 97%) failed mainly at low dose points of increased uncertainty. Conclusion: FXG gel/optical CT is an efficient method for level-2 commissioning of brachytherapy MBDCAs. Target dosimetry is not affected from uncertainty introduced by TG43 assumptions in 192Ir skin brachytherapy

  7. Partition Model-Based 99mTc-MAA SPECT/CT Predictive Dosimetry Compared with 90Y TOF PET/CT Posttreatment Dosimetry in Radioembolization of Hepatocellular Carcinoma: A Quantitative Agreement Comparison.

    Science.gov (United States)

    Gnesin, Silvano; Canetti, Laurent; Adib, Salim; Cherbuin, Nicolas; Silva Monteiro, Marina; Bize, Pierre; Denys, Alban; Prior, John O; Baechler, Sebastien; Boubaker, Ariane

    2016-11-01

    90 Y-microsphere selective internal radiation therapy (SIRT) is a valuable treatment in unresectable hepatocellular carcinoma (HCC). Partition-model predictive dosimetry relies on differential tumor-to-nontumor perfusion evaluated on pretreatment 99m Tc-macroaggregated albumin (MAA) SPECT/CT. The aim of this study was to evaluate agreement between the predictive dosimetry of 99m Tc-MAA SPECT/CT and posttreatment dosimetry based on 90 Y time-of-flight (TOF) PET/CT. We compared the 99m Tc-MAA SPECT/CT results for 27 treatment sessions (25 HCC patients, 41 tumors) with 90 Y SIRT (7 glass spheres, 20 resin spheres) and the posttreatment 90 Y TOF PET/CT results. Three-dimensional voxelized dose maps were computed from the 99m Tc-MAA SPECT/CT and 90 Y TOF PET/CT data. Mean absorbed dose ([Formula: see text]) was evaluated to compute the predicted-to-actual dose ratio ([Formula: see text]) in tumor volumes (TVs) and nontumor volumes (NTVs) for glass and resin spheres. The Lin concordance ([Formula: see text]) was used to measure accuracy ([Formula: see text]) and precision (ρ). Administered activity ranged from 0.8 to 1.9 GBq for glass spheres and from 0.6 to 3.4 GBq for resin spheres, and the respective TVs ranged from 2 to 125 mL and from 6 to 1,828 mL. The mean dose [Formula: see text] was 240 Gy for glass and 122 Gy for resin in TVs and 72 Gy for glass and 47 Gy for resin in NTVs. [Formula: see text] was 1.46 ± 0.58 (0.65-2.53) for glass and 1.16 ± 0.41 (0.54-2.54) for resin, and the respective values for [Formula: see text] were 0.88 ± 0.15 (0.56-1.00) and 0.86 ± 0.2 (0.58-1.35). DR variability was substantially lower in NTVs than in TVs. The Lin concordance between [Formula: see text] and [Formula: see text] (resin) was significantly better for tumors larger than 150 mL than for tumors 150 mL or smaller ([Formula: see text] = 0.93 and [Formula: see text] = 0.95 vs. [Formula: see text] = 0.57 and [Formula: see text] = 0.93; P < 0.05). In 90 Y radioembolization

  8. Nevada test site neutron dosimetry-problems/solutions

    International Nuclear Information System (INIS)

    Sygitowicz, L.S.; Bastian, C.T.; Wells, I.J.; Koch, P.N.

    1991-01-01

    Historically, neutron dosimetry at the NTS was done using NTA film and albedo LiF TLD's. In 1987 the dosimeter type was changed from the albedo TLD based system to a CR-39 track etch based system modeled after the program developed by D. Hankins at LLNL. Routine issue and return is performed quarterly for selected personnel using bar-code readers at permanent locations. The capability exists for work site issue as-needed. Issue data are transmitted by telephone to a central computer where it is stored until the dosimeter is returned, processed and read, and the dose calculation is performed. Dose equivalent calculations are performed using LOTUS 123 and the results are printed as a hard copy record. The issue and dose information are hand-entered into the Dosimetry database. An application is currently being developed to automate this sequence

  9. A study on depth-scaling of plastic phantom in electron beam dosimetry

    International Nuclear Information System (INIS)

    Kojima, T.; Saitoh, H.; Kawachi, T.; Katayose, T.; Myojyoyama, A.

    2005-01-01

    In recommendations of several standard dosimetry, water is defined as the reference medium, however, the water substitute plastic phantoms are highly discouraged. Nevertheless, in the case of accurate chamber positioning in water is not possible, or no waterproof chamber is available, their use is permitted at beam qualities R 50 2 (E 0 pl obtained from a ratio of electron average penetration depth; z av , half value depth ratio; (R 50 ) w,m from Monte Carlo dose calculation and that from measurements, are compared each other. As a result, there are slight differences in depth-scaling factor between obtained from simulation results and from measurements. These results indicate that c pl has to be studied more detail for the sake of precise electron dosimetry in plastic phantoms. (author)

  10. Small Radiation Beam Dosimetry for Radiosurgery of Trigeminal Neuralgia: One Case Analysis

    International Nuclear Information System (INIS)

    Garcia-Garduno, O. A.; Larraga-Gutierrez, J. M.; Rodriguez-Villafuerte, M.; Martinez-Davalos, A.; Moreno-Jimenez, S.; Suarez-Campos, J. J.; Celis, M. A.

    2008-01-01

    The use of small radiation beams for trigeminal neuralgia (TN) treatment requires high precision and accuracy in dose distribution calculations and delivery. Special attention must be kept on the type of detector to be used. In this work, the use of GafChromic EBT registered radiochromic and X-OMAT V2 radiographic films for small radiation beam characterization is reported. The dosimetric information provided by the films (total output factors, tissue maximum ratios and off axis ratios) is compared against measurements with a shielded solid state (diode) reference detector. The film dosimetry was used for dose distribution calculations for the treatment of trigeminal neuralgia radiosurgery. Comparison of the isodose curves shows that the dosimetry produced with the X-OMAT radiographic film overestimates the dose distributions in the penumbra region

  11. Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Hurst, G S; Ritchie, R H; Sanders, F W; Reinhardt, P W; Auxier, J A; Wagner, E B; Callihan, A D; Morgan, K Z [Health Physics Division, Oak Ridge National Laboratory, Oak Ridge, TN (United States)

    1962-03-15

    The methods of dosimetry used for investigation of the doses received by the individuals exposed in the Yugoslav accident were essentially those used in connection with the Oak Ridge Y-12 accident. An outline of the general scheme is as follows: When fast neutrons enter the human body, most of these are moderated to thermal energy and a small fraction of these are captured by a (n, gamma) process in Na sup 2 sup 3 , giving rise to Na sup 2 sup 4 , which by virtue of its emission of high-energy gamma rays with a half life of 14.8 h, is easily detected. It has been shown that the probability of capture, making Na sup 2 sup 4 , is not a strong function of the energy of the fast neutrons and that the probability of capture for neutrons is higher in the fast region than in the thermal region. Thus, the uniform distribution of Na sup 2 sup 3 in the human body provides an excellent means of normalizing the neutron exposure of an individual. in particular, for a given neutron energy spectrum the fast neutron dose is proportional to the ratio Na sup 2 sup 4 /Na sup 2 sup 3 in the body or in the blood system. This method of normalization is quite important in the dosimetry of radiation accidents since no assumptions need be made about the exact location of an individual at the time of the energy release. The importance of this fact can be made clear by reference to the Y-12 accident where it was shown by calculation of the neutron dose based on the known number of fissions and the stated location of the individual that one of the surviving individuals would have received a dose several times the lethal value. To accomplish the measurements described, the zero power R sub B reactor was operated in two ranges of power level, 'low' power and 'high 'power. Neutron leakage spectrum was obtained by multigroup approximation of the Boltzmann transport equation. Prompt gamma rays from fission products, from capture in the moderator and fuel cladding as well as in tank walls are given

  12. Quality assurance in radiotherapy dosimetry in China

    International Nuclear Information System (INIS)

    Li Kaibao; Luo Suming; Cheng Jinsheng; He Zhijian; An Jinggang; Hu Yimin; Feng Ningyuan

    2002-01-01

    In 1995, the SSDL in the Laboratory of Industrial Hygiene cooperated with Beijing Cancer Hospital, Chinese Academy of Medical science joined the IAEA Co-ordinated Research Programme (NO.8769/RO). According to the requirements of the project, an External Audit Group (EAG) in China was established in 1996 with the responsibilities of operating TLD-based quality audit for radiotherapy dosimetry. Since then. The national TLD dose quality audit services have been carried out in 7 provinces in China. Besides this, the national programmes for brachytherapy and stereostatic radiosurgery (SRS) treatment dosimetry were initiated in 2001. The activity measurement intercomparison between the SSDL and some hospitals for Ir-192 HDR brachytherapy sources has been performed using a HDR well-type ionization chamber (Model HDR 1000 plus) and CDX-2000A Charge Digitizer, which were calibrated in Accredited Dosimetry Calibration Laboratory, University of Wisconsin, USA. The preliminary results indicated that the agreement between SSDL measured activity and hospital stated activity was within ±5% for more than 80% of total participants

  13. Results of the dosimetry intercomparison

    International Nuclear Information System (INIS)

    Dure, Elsa S.

    2000-07-01

    The appropriate way to verify the accuracy of the results of dose reported by the laboratories that offer lend personal dosimetry service is in the periodic participation of round of intercomparison dosimetry, undertaken by laboratories whose standards are trace (Secondary Laboratory). The Laboratory of External Personal Dosimetry of the CNEA-PY has participated in three rounds of intercomparison. The first two were organized in the framework of the Model Project RLA/9/030 RADIOLOGICAL WASTE SECURITY, and the irradiations were carried out in the Laboratory of Regional Calibration of the Center of Nuclear Technology Development, Belo Horizonte-Brazil (1998) and in the National Laboratory of Metrology of the ionizing radiations of the Institute of Radioprotection and Dosimetry, Rio de Janeiro-Brazil (1999). The third was organized by the IAEA and the irradiations were made in the Physikalisch-Technische Bundesanstalt PTB, Braunschweig - Federal Republic of Germany (1999-2000) [es

  14. Dosimetry standards for radiation processing

    International Nuclear Information System (INIS)

    Farrar, H. IV

    1999-01-01

    For irradiation treatments to be reproducible in the laboratory and then in the commercial environment, and for products to have certified absorbed doses, standardized dosimetry techniques are needed. This need is being satisfied by standards being developed by experts from around the world under the auspices of Subcommittee E10.01 of the American Society for Testing and Materials (ASTM). In the time period since it was formed in 1984, the subcommittee has grown to 150 members from 43 countries, representing a broad cross-section of industry, government and university interests. With cooperation from other international organizations, it has taken the combined part-time effort of all these people more than 13 years to complete 24 dosimetry standards. Four are specifically for food irradiation or agricultural applications, but the majority apply to all forms of gamma, x-ray, Bremsstrahlung and electron beam radiation processing, including dosimetry for sterilization of health care products and the radiation processing of fruits, vegetables, meats, spices, processed foods, plastics, inks, medical wastes and paper. An additional 6 standards are under development. Most of the standards provide exact procedures for using individual dosimetry systems or for characterizing various types of irradiation facilities, but one covers the selection and calibration of dosimetry systems, and another covers the treatment of uncertainties. Together, this set of standards covers essentially all aspects of dosimetry for radiation processing. The first 20 of these standards have been adopted in their present form by the International Organization of Standardization (ISO), and will be published by ISO in 1999. (author)

  15. Review on the characteristics of radiation detectors for dosimetry and imaging

    International Nuclear Information System (INIS)

    Seco, Joao; Clasie, Ben; Partridge, Mike

    2014-01-01

    The enormous advances in the understanding of human anatomy, physiology and pathology in recent decades have led to ever-improving methods of disease prevention, diagnosis and treatment. Many of these achievements have been enabled, at least in part, by advances in ionizing radiation detectors. Radiology has been transformed by the implementation of multi-slice CT and digital x-ray imaging systems, with silver halide films now largely obsolete for many applications. Nuclear medicine has benefited from more sensitive, faster and higher-resolution detectors delivering ever-higher SPECT and PET image quality. PET/MR systems have been enabled by the development of gamma ray detectors that can operate in high magnetic fields. These huge advances in imaging have enabled equally impressive steps forward in radiotherapy delivery accuracy, with 4DCT, PET and MRI routinely used in treatment planning and online image guidance provided by cone-beam CT. The challenge of ensuring safe, accurate and precise delivery of highly complex radiation fields has also both driven and benefited from advances in radiation detectors. Detector systems have been developed for the measurement of electron, intensity-modulated and modulated arc x-ray, proton and ion beams, and around brachytherapy sources based on a very wide range of technologies. The types of measurement performed are equally wide, encompassing commissioning and quality assurance, reference dosimetry, in vivo dosimetry and personal and environmental monitoring. In this article, we briefly introduce the general physical characteristics and properties that are commonly used to describe the behaviour and performance of both discrete and imaging detectors. The physical principles of operation of calorimeters; ionization and charge detectors; semiconductor, luminescent, scintillating and chemical detectors; and radiochromic and radiographic films are then reviewed and their principle applications discussed. Finally, a general

  16. Dosimetry tools and techniques for IMRT

    International Nuclear Information System (INIS)

    Low, Daniel A.; Moran, Jean M.; Dempsey, James F.; Dong Lei; Oldham, Mark

    2011-01-01

    Intensity modulated radiation therapy (IMRT) poses a number of challenges for properly measuring commissioning data and quality assurance (QA) radiation dose distributions. This report provides a comprehensive overview of how dosimeters, phantoms, and dose distribution analysis techniques should be used to support the commissioning and quality assurance requirements of an IMRT program. The proper applications of each dosimeter are described along with the limitations of each system. Point detectors, arrays, film, and electronic portal imagers are discussed with respect to their proper use, along with potential applications of 3D dosimetry. Regardless of the IMRT technique utilized, some situations require the use of multiple detectors for the acquisition of accurate commissioning data. The overall goal of this task group report is to provide a document that aids the physicist in the proper selection and use of the dosimetry tools available for IMRT QA and to provide a resource for physicists that describes dosimetry measurement techniques for purposes of IMRT commissioning and measurement-based characterization or verification of IMRT treatment plans. This report is not intended to provide a comprehensive review of commissioning and QA procedures for IMRT. Instead, this report focuses on the aspects of metrology, particularly the practical aspects of measurements that are unique to IMRT. The metrology of IMRT concerns the application of measurement instruments and their suitability, calibration, and quality control of measurements. Each of the dosimetry measurement tools has limitations that need to be considered when incorporating them into a commissioning process or a comprehensive QA program. For example, routine quality assurance procedures require the use of robust field dosimetry systems. These often exhibit limitations with respect to spatial resolution or energy response and need to themselves be commissioned against more established dosimeters. A chain of

  17. Neutron dosimetry for radiation damage in fission and fusion reactors

    International Nuclear Information System (INIS)

    Smith, D.L.

    1979-01-01

    The properties of materials subjected to the intense neutron radiation fields characteristic of fission power reactors or proposed fusion energy devices is a field of extensive current research. These investigations seek important information relevant to the safety and economics of nuclear energy. In high-level radiation environments, neutron metrology is accomplished predominantly with passive techniques which require detailed knowledge about many nuclear reactions. The quality of neutron dosimetry has increased noticeably during the past decade owing to the availability of new data and evaluations for both integral and differential cross sections, better quantitative understanding of radioactive decay processes, improvements in radiation detection technology, and the development of reliable spectrum unfolding procedures. However, there are problems caused by the persistence of serious integral-differential discrepancies for several important reactions. There is a need to further develop the data base for exothermic and low-threshold reactions needed in thermal and fast-fission dosimetry, and for high-threshold reactions needed in fusion-energy dosimetry. The unsatisfied data requirements for fission reactor dosimetry appear to be relatively modest and well defined, while the needs for fusion are extensive and less well defined because of the immature state of fusion technology. These various data requirements are examined with the goal of providing suggestions for continued dosimetry-related nuclear data research

  18. [Automatic Extraction and Analysis of Dosimetry Data in Radiotherapy Plans].

    Science.gov (United States)

    Song, Wei; Zhao, Di; Lu, Hong; Zhang, Biyun; Ma, Jun; Yu, Dahai

    To improve the efficiency and accuracy of extraction and analysis of dosimetry data in radiotherapy plans for a batch of patients. With the interface function provided in Matlab platform, a program was written to extract the dosimetry data exported from treatment planning system in DICOM RT format and exported the dose-volume data to an Excel file with the SPSS compatible format. This method was compared with manual operation for 14 gastric carcinoma patients to validate the efficiency and accuracy. The output Excel data were compatible with SPSS in format, the dosimetry data error for PTV dose interval of 90%-98%, PTV dose interval of 99%-106% and all OARs were -3.48E-5 ± 3.01E-5, -1.11E-3 ± 7.68E-4, -7.85E-5 ± 9.91E-5 respectively. Compared with manual operation, the time required was reduced from 5.3 h to 0.19 h and input error was reduced from 0.002 to 0. The automatic extraction of dosimetry data in DICOM RT format for batch patients, the SPSS compatible data exportation, quick analysis were achieved in this paper. The efficiency of clinical researches based on dosimetry data analysis of large number of patients will be improved with this methods.

  19. The dosimetry programme of the IAEA

    International Nuclear Information System (INIS)

    1987-01-01

    Describes the activities of the IAEA's Dosimetry Laboratory which provides calibration and comparison services for secondary standard dosimetry laboratories (SSDLs) of Member States. In addition, a joint IAEA/WHO postal dosimetry service has been established for radiotherapy centers. The International Measurement System and the calibration ''chain'' from measurement standard instruments of the International Bureau of Weights and Measurements (BIPM) through the primary and secondary standards to the dosimeters of the users are presented as well

  20. International beta-dosimetry symposium. Program and abstracts

    International Nuclear Information System (INIS)

    1983-02-01

    Abstracts of the presentations at the symposium are contained in this volume. Problems associated with beta dosimetry, beta detectors and dosemeters, and current development programs are described. Each abstract has been indexed separately for inclusion in the Energy Data Base

  1. Main activities of the Latin American Network of Biological Dosimetry (LBDNet)

    International Nuclear Information System (INIS)

    Di Giorgio, M.; Vallerga, M.B.; Radl, A.; Taja, M.R.; Stuck Oliveira, M.; Valdivia, P.; Garcia Lima, O.; Lamadrid, A.; Gonzalez Mesa, J.E.; Romero Aguilera, I.; Mandina Cardoso, T.; Guerrero Carbajal, C.; Arceo Maldonado, C.; Espinoza, M.; Martinez Lopez, W.; Di Tomasso, M.; Barquinero, F.; Roy, L.

    2010-01-01

    The Latin American Biological Dosimetry Network (LBDNET) was constituted in 2007 for mutual assistance in case of a radiation emergency in the region supported by IAEA Technical Cooperation Projects RLA/9/054 and RLA/9/061. The main objectives are: a) to strengthen the technical capacities of Biological Dosimetry Services belonging to laboratories existing in the region (Argentine, Brazil, Chile, Cuba, Mexico, Peru and Uruguay) integrated in National Radiological Emergency Plans to provide a rapid biodosimetric response in a coordinated manner between countries and with RANET-IAEA/BioDoseNet-WHO, b) to provide support to other countries in the region lacking Biological Dosimetry laboratories, c) to consolidate the organization of the Latin American Biological Dosimetry Network for mutual assistance. The activities developed include technical meetings for protocols and chromosomal aberration scoring criteria unification, blood samples cultures exercises, chromosomal aberrations analysis at microscope, discussion of statistical methods and specialized software for dose calculation, the intercomparison between laboratory data after the analysis of slides with irradiated material and the intercomparison of the analysis of captured images distributed electronically in the WEB. The last exercise was the transportation of an irradiated human blood sample to countries inside and outside of the region. At the moment the exercises are concluded and they are pending to be published in reference journals. Results obtained show the capacity in the region for a biodosimetric response to a radiological accident. In the future the network will integrate techniques for high dose exposure evaluation and will enhance the interaction with other emergency systems in the region. (authors) [es

  2. Hematological dosimetry

    International Nuclear Information System (INIS)

    Fluery-Herard, A.

    1991-01-01

    The principles of hematological dosimetry after acute or protracted whole-body irradiation are reviewed. In both cases, over-exposure is never homogeneous and the clinical consequences, viz medullary aplasia, are directly associated with the mean absorbed dose and the seriousness and location of the overexposure. The main hematological data required to assess the seriousness of exposure are the following: repeated blood analysis, blood precursor cultures, as indicators of whole-body exposure; bone marrow puncture, medullary precursor cultures and medullary scintigraphy as indicators of the importance of a local over-exposure and capacity for spontaneous repair. These paraclinical investigations, which are essential for diagnosis and dosimetry, are also used for surveillance and for the main therapeutic issues [fr

  3. Establishment of the Dosicard operational dosimetry system in a nuclear studies center

    International Nuclear Information System (INIS)

    Banchetry, C.

    2001-01-01

    Since the decree of March 1999, each employer of the French nuclear industry must set an operational dosimetry in its company. The method is based on electronic dosimeters equipped with alarms and worn by all the employees. The dosimeters are linked to a computer network. The operational dosimetry is recommended, to optimize the protection of workers and limit the doses received, to respect the principle of equity between the workers, to preserve a ''margin of dose'' in case of any unexpected event. The CEA executives have decided to use the EURISYS MESURES DOSICARD as an operational and complementary dosimetry tool. (author)

  4. Internal Dosimetry for Nuclear Power Program

    International Nuclear Information System (INIS)

    Wo, Y.M.

    2011-01-01

    Internal dosimetry which refers to dosage estimation from internal part of an individual body is an important and compulsory component in order to ensure the safety of the personnel involved in operational of a Nuclear Power Program. Radionuclides particle may deposit in the human being through several pathways and release wave and/or particle radiation to irradiate that person and give dose to body until it been excreted or completely decayed from the body. Type of radionuclides of concerning, monitoring program, equipment's and technique used to measure the concentration level of such radionuclides and dose calculation will be discussed in this article along with the role and capability of Malaysian Nuclear Agency. (author)

  5. Development and current state of dosimetry in Cuba

    International Nuclear Information System (INIS)

    Prieto Miranda, E.F.; Cuesta Fuente, G.; Chavez Ardanza, A.

    1999-01-01

    In Cuba, the application of the radiation technologies has been growing in the last years, and at present there are several dosimetry systems with different ranges of absorbed dose. Diverse researches were carried out on high dose dosimetry with the following dosimetry systems: Fricke, ceric-cerous sulfate, ethanol-chlorobenzene, cupric sulfate and Perspex (Red 4034 AE and Clear HX). In this paper the development achieved during the last 15 years in the high dose dosimetry for radiation processing in Cuba is presented, as well as, the current state of different dosimetry systems employed for standardization and for process control. The paper also reports the results of dosimetry intercomparison studies that were performed with the Ezeiza Atomic Center of Argentine and the International Dose Assurance Service (IDAS) of IAEA. (author)

  6. Dosimetry systems in nuclear power stations

    International Nuclear Information System (INIS)

    Weidmann, U.

    1992-01-01

    In the following paper the necessity of the use of electronic dosimetry systems in nuclear power stations is presented, also encompassing the tasks which this type of systems has to fulfill. Based on examples the construction principles and the application possibilities of a PC supported system are described. 5 figs

  7. MicroCT-Based Skeletal Models for Use in Tomographic Voxel Phantoms for Radiological Protection

    International Nuclear Information System (INIS)

    Bolch, Wesley

    2010-01-01

    The University of Florida (UF) proposes to develop two high-resolution image-based skeletal dosimetry models for direct use by ICRP Committee 2's Task Group on Dose Calculation in their forthcoming Reference Voxel Male (RVM) and Reference Voxel Female (RVF) whole-body dosimetry phantoms. These two phantoms are CT-based, and thus do not have the image resolution to delineate and perform radiation transport modeling of the individual marrow cavities and bone trabeculae throughout their skeletal structures. Furthermore, new and innovative 3D microimaging techniques will now be required for the skeletal tissues following Committee 2's revision of the target tissues of relevance for radiogenic bone cancer induction. This target tissue had been defined in ICRP Publication 30 as a 10-(micro)m cell layer on all bone surfaces of trabecular and cortical bone. The revised target tissue is now a 50-(micro)m layer within the marrow cavities of trabecular bone only and is exclusive of the marrow adipocytes. Clearly, this new definition requires the use of 3D microimages of the trabecular architecture not available from past 2D optical studies of the adult skeleton. With our recent acquisition of two relatively young cadavers (males of age 18-years and 40-years), we will develop a series of reference skeletal models that can be directly applied to (1) the new ICRP reference voxel man and female phantoms developed for the ICRP, and (2) pediatric phantoms developed to target the ICRP reference children. Dosimetry data to be developed will include absorbed fractions for internal beta and alpha-particle sources, as well as photon and neutron fluence-to-dose response functions for direct use in external dosimetry studies of the ICRP reference workers and members of the general public

  8. MicroCT-Based Skeletal Models for Use in Tomographic Voxel Phantoms for Radiological Protection

    Energy Technology Data Exchange (ETDEWEB)

    Bolch, Wesley [Univ. of Florida, Gainesville, FL (United States)

    2010-03-30

    The University of Florida (UF) proposes to develop two high-resolution image-based skeletal dosimetry models for direct use by ICRP Committee 2’s Task Group on Dose Calculation in their forthcoming Reference Voxel Male (RVM) and Reference Voxel Female (RVF) whole-body dosimetry phantoms. These two phantoms are CT-based, and thus do not have the image resolution to delineate and perform radiation transport modeling of the individual marrow cavities and bone trabeculae throughout their skeletal structures. Furthermore, new and innovative 3D microimaging techniques will now be required for the skeletal tissues following Committee 2’s revision of the target tissues of relevance for radiogenic bone cancer induction. This target tissue had been defined in ICRP Publication 30 as a 10-μm cell layer on all bone surfaces of trabecular and cortical bone. The revised target tissue is now a 50-μm layer within the marrow cavities of trabecular bone only and is exclusive of the marrow adipocytes. Clearly, this new definition requires the use of 3D microimages of the trabecular architecture not available from past 2D optical studies of the adult skeleton. With our recent acquisition of two relatively young cadavers (males of age 18-years and 40-years), we will develop a series of reference skeletal models that can be directly applied to (1) the new ICRP reference voxel man and female phantoms developed for the ICRP, and (2) pediatric phantoms developed to target the ICRP reference children. Dosimetry data to be developed will include absorbed fractions for internal beta and alpha-particle sources, as well as photon and neutron fluence-to-dose response functions for direct use in external dosimetry studies of the ICRP reference workers and members of the general public

  9. Radiation dosimetry and spectrometry with superheated emulsions

    International Nuclear Information System (INIS)

    D'Errico, Francesco

    2001-01-01

    Detectors based on emulsions of overexpanded halocarbon droplets in tissue equivalent aqueous gels or soft polymers, known as 'superheated drop detectors' or 'bubble (damage) detectors', have been used in radiation detection, dosimetry and spectrometry for over two decades. Recent technological advances have led to the introduction of several instruments for individual and area monitoring: passive integrating meters based on the optical or volumetric registration of the bubbles, and active counters detecting bubble nucleations acoustically. These advances in the instrumentation have been matched by the progress made in the production of stable and well-specified emulsions of superheated droplets. A variety of halocarbons are employed in the formulation of the detectors, and this permits a wide range of applications. In particular, halocarbons with a moderate degree of superheat, i.e. a relatively small difference between their operating temperature and boiling point, can be used in neutron dosimetry and spectrometry since they are only nucleated by energetic heavy ions such as those produced by fast neutrons. More recently, halocarbons with an elevated degree of superheat have been utilised to produce emulsions that nucleate with much smaller energy deposition and detect low linear energy transfer radiations, such as photons and electrons. This paper reviews the detector physics of superheated emulsions and their applications in radiation measurements, particularly in neutron dosimetry and spectrometry

  10. Statistical issues in biological radiation dosimetry for risk assessment using stable chromosome aberrations

    International Nuclear Information System (INIS)

    Cologne, J.B.; Preston, D.L.

    1998-01-01

    Biological dosimeters are useful for epidemiologic risk assessment in populations exposed to catastrophic nuclear events and as a means of validating physical dosimetry in radiation workers. Application requires knowledge of the magnitude of uncertainty in the biological dose estimates and an understanding of potential statistical pitfalls arising from their use. This paper describes the statistical aspects of biological dosimetry in general and presents a detailed analysis in the specific case of dosimetry for risk assessment using stable chromosome aberration frequency. Biological dose estimates may be obtained from a dose-response curve, but negative estimates can result and adjustment must be made for regression bias due to imprecise estimation when the estimates are used in regression analyses. Posterior-mean estimates, derived as the mean of the distribution of true doses compatible with a given value of the biological endpoint, have several desirable properties: they are nonnegative, less sensitive to extreme skewness in the true dose distribution, and implicitly adjusted to avoid regression bias. The methods necessitate approximating the true-dose distribution in the population in which biological dosimetry is being applied, which calls for careful consideration of this distribution through other information. An important question addressed here is to what extent the methods are robust to misspecification of this distribution, because in many applications of biological dosimetry it cannot be characterized well. The findings suggest that dosimetry based solely on stable chromosome aberration frequency may be useful for population-based risk assessment

  11. Quantitative evaluation of patient-specific quality assurance using online dosimetry system

    Science.gov (United States)

    Jung, Jae-Yong; Shin, Young-Ju; Sohn, Seung-Chang; Min, Jung-Whan; Kim, Yon-Lae; Kim, Dong-Su; Choe, Bo-Young; Suh, Tae-Suk

    2018-01-01

    In this study, we investigated the clinical performance of an online dosimetry system (Mobius FX system, MFX) by 1) dosimetric plan verification using gamma passing rates and dose volume metrics and 2) error-detection capability evaluation by deliberately introduced machine error. Eighteen volumetric modulated arc therapy (VMAT) plans were studied. To evaluate the clinical performance of the MFX, we used gamma analysis and dose volume histogram (DVH) analysis. In addition, to evaluate the error-detection capability, we used gamma analysis and DVH analysis utilizing three types of deliberately introduced errors (Type 1: gantry angle-independent multi-leaf collimator (MLC) error, Type 2: gantry angle-dependent MLC error, and Type 3: gantry angle error). A dosimetric verification comparison of physical dosimetry system (Delt4PT) and online dosimetry system (MFX), gamma passing rates of the two dosimetry systems showed very good agreement with treatment planning system (TPS) calculation. For the average dose difference between the TPS calculation and the MFX measurement, most of the dose metrics showed good agreement within a tolerance of 3%. For the error-detection comparison of Delta4PT and MFX, the gamma passing rates of the two dosimetry systems did not meet the 90% acceptance criterion with the magnitude of error exceeding 2 mm and 1.5 ◦, respectively, for error plans of Types 1, 2, and 3. For delivery with all error types, the average dose difference of PTV due to error magnitude showed good agreement between calculated TPS and measured MFX within 1%. Overall, the results of the online dosimetry system showed very good agreement with those of the physical dosimetry system. Our results suggest that a log file-based online dosimetry system is a very suitable verification tool for accurate and efficient clinical routines for patient-specific quality assurance (QA).

  12. Development of the two Korean adult tomographic computational phantoms for organ dosimetry

    International Nuclear Information System (INIS)

    Lee, Choonsik; Lee, Choonik; Park, Sang-Hyun; Lee, Jai-Ki

    2006-01-01

    Following the previously developed Korean tomographic phantom, KORMAN, two additional whole-body tomographic phantoms of Korean adult males were developed from magnetic resonance (MR) and computed tomography (CT) images, respectively. Two healthy male volunteers, whose body dimensions were fairly representative of the average Korean adult male, were recruited and scanned for phantom development. Contiguous whole body MR images were obtained from one subject exclusive of the arms, while whole-body CT images were acquired from the second individual. A total of 29 organs and tissues and 19 skeletal sites were segmented via image manipulation techniques such as gray-level thresholding, region growing, and manual drawing, in which each of segmented image slice was subsequently reviewed by an experienced radiologist for anatomical accuracy. The resulting phantoms, the MR-based KTMAN-1 (Korean Typical MAN-1) and the CT-based KTMAN-2 (Korean Typical MAN-2), consist of 300x150x344 voxels with a voxel resolution of 2x2x5 mm 3 for both phantoms. Masses of segmented organs and tissues were calculated as the product of a nominal reference density, the prevoxel volume, and the cumulative number of voxels defining each organs or tissue. These organs masses were then compared with those of both the Asian and the ICRP reference adult male. Organ masses within both KTMAN-1 and KTMAN-2 showed differences within 40% of Asian and ICRP reference values, with the exception of the skin, gall bladder, and pancreas which displayed larger differences. The resulting three-dimensional binary file was ported to the Monte Carlo code MCNPX2.4 to calculate organ doses following external irradiation for illustrative purposes. Colon, lung, liver, and stomach absorbed doses, as well as the effective dose, for idealized photon irradiation geometries (anterior-posterior and right lateral) were determined, and then compared with data from two other tomographic phantoms (Asian and Caucasian), and

  13. Revisiting photodynamic therapy dosimetry: reductionist and surrogate approaches to facilitate clinical success

    International Nuclear Information System (INIS)

    Pogue, Brian W; Elliott, Jonathan T; Kanick, Stephen C; Davis, Scott C; Samkoe, Kimberley S; Maytin, Edward V; Pereira, Stephen P; Hasan, Tayyaba

    2016-01-01

    Photodynamic therapy (PDT) can be a highly complex treatment, with many parameters influencing treatment efficacy. The extent to which dosimetry is used to monitor and standardize treatment delivery varies widely, ranging from measurement of a single surrogate marker to comprehensive approaches that aim to measure or estimate as many relevant parameters as possible. Today, most clinical PDT treatments are still administered with little more than application of a prescribed drug dose and timed light delivery, and thus the role of patient-specific dosimetry has not reached widespread clinical adoption. This disconnect is at least partly due to the inherent conflict between the need to measure and understand multiple parameters in vivo in order to optimize treatment, and the need for expedience in the clinic and in the regulatory and commercialization process. Thus, a methodical approach to selecting primary dosimetry metrics is required at each stage of translation of a treatment procedure, moving from complex measurements to understand PDT mechanisms in pre-clinical and early phase I trials, towards the identification and application of essential dose-limiting and/or surrogate measurements in phase II/III trials. If successful, identifying the essential and/or reliable surrogate dosimetry measurements should help facilitate increased adoption of clinical PDT. In this paper, examples of essential dosimetry points and surrogate dosimetry tools that may be implemented in phase II/III trials are discussed. For example, the treatment efficacy as limited by light penetration in interstitial PDT may be predicted by the amount of contrast uptake in CT, and so this could be utilized as a surrogate dosimetry measurement to prescribe light doses based upon pre-treatment contrast. Success of clinical ALA-based skin lesion treatment is predicted almost uniquely by the explicit or implicit measurements of photosensitizer and photobleaching, yet the individualization of treatment

  14. A broad-group cross-section library based on ENDF/B-VII.0 for fast neutron dosimetry Applications

    Energy Technology Data Exchange (ETDEWEB)

    Alpan, F.A. [Westinghouse Electric Company, 1000 Westinghouse Drive, Cranberry Township, PA 16066 (United States)

    2011-07-01

    A new ENDF/B-VII.0-based coupled 44-neutron, 20-gamma-ray-group cross-section library was developed to investigate the latest evaluated nuclear data file (ENDF) ,in comparison to ENDF/B-VI.3 used in BUGLE-96, as well as to generate an objective-specific library. The objectives selected for this work consisted of dosimetry calculations for in-vessel and ex-vessel reactor locations, iron atom displacement calculations for reactor internals and pressure vessel, and {sup 58}Ni(n,{gamma}) calculation that is important for gas generation in the baffle plate. The new library was generated based on the contribution and point-wise cross-section-driven (CPXSD) methodology and was applied to one of the most widely used benchmarks, the Oak Ridge National Laboratory Pool Critical Assembly benchmark problem. In addition to the new library, BUGLE-96 and an ENDF/B-VII.0-based coupled 47-neutron, 20-gamma-ray-group cross-section library was generated and used with both SNLRML and IRDF dosimetry cross sections to compute reaction rates. All reaction rates computed by the multigroup libraries are within {+-} 20 % of measurement data and meet the U. S. Nuclear Regulatory Commission acceptance criterion for reactor vessel neutron exposure evaluations specified in Regulatory Guide 1.190. (authors)

  15. Twenty new ISO standards on dosimetry for radiation processing

    International Nuclear Information System (INIS)

    Farrar IV, H.

    2000-01-01

    Twenty standards on essentially all aspects of dosimetry for radiation processing were published as new ISO standards in December 1998. The standards are based on 20 standard practices and guides developed over the past 14 years by Subcommittee E10.01 of the American Society for Testing and Materials (ASTM). The transformation to ISO standards using the 'fast track' process under ISO Technical Committee 85 (ISO/TC85) commenced in 1995 and resulted in some overlap of technical information between three of the new standards and the existing ISO Standard 11137 Sterilization of health care products - Requirements for validation and routine control - Radiation sterilization. Although the technical information in these four standards was consistent, compromise wording in the scopes of the three new ISO standards to establish precedence for use were adopted. Two of the new ISO standards are specifically for food irradiation applications, but the majority apply to all forms of gamma, X-ray, and electron beam radiation processing, including dosimetry for sterilization of health care products and the radiation processing of fruit, vegetables, meats, spices, processed foods, plastics, inks, medical wastes, and paper. Most of the standards provide exact procedures for using individual dosimetry systems or for characterizing various types of irradiation facilities, but one covers the selection and calibration of dosimetry systems, and another covers the treatment of uncertainties using the new ISO Type A and Type B evaluations. Unfortunately, nine of the 20 standards just adopted by the ISO are not the most recent versions of these standards and are therefore already out of date. To help solve this problem, efforts are being made to develop procedures to coordinate the ASTM and ISO development and revision processes for these and future ASTM-originating dosimetry standards. In the meantime, an additional four dosimetry standards have recently been published by the ASTM but have

  16. Radiochromic dye film for ionizing and non ionizing radiation dosimetry

    International Nuclear Information System (INIS)

    Said, F.I.; Elbahay, A.Z.

    1984-01-01

    During the present study different types of radiochromic dye films have been investigated for γ-ray as well as ultraviolet radiation dosimetry. The technique is based on the change in absorption spectra for dosed samples with special emphasis at optical absorption bands observed at 510nm and 605nm. Dose response of different types of radiochromic dye films was determined in the range between 1 to 40 KGy γ rays. The technique is used for γ-ray dosimetry in processing with high quality. The increasing use of U.V. light in industry and medicine makes it necessary to have simple practical methods for U.V. dosimetry. To this purpose radiochromic dye films are suggested for the first time. The response was investigated for emission consisted mainly of 254 and 366nm photons over the range from 50-700 m W.S. cm -2 . The experimental results indicate that radiochromic dye films are practical and simple technique for γ-ray and U.V. dosimetry for industrial and medical applications

  17. Heterogeneity phantoms for visualization of 3D dose distributions by MRI-based polymer gel dosimetry

    International Nuclear Information System (INIS)

    Watanabe, Yoichi; Mooij, Rob; Mark Perera, G.; Maryanski, Marek J.

    2004-01-01

    Heterogeneity corrections in dose calculations are necessary for radiation therapy treatment plans. Dosimetric measurements of the heterogeneity effects are hampered if the detectors are large and their radiological characteristics are not equivalent to water. Gel dosimetry can solve these problems. Furthermore, it provides three-dimensional (3D) dose distributions. We used a cylindrical phantom filled with BANG-3 registered polymer gel to measure 3D dose distributions in heterogeneous media. The phantom has a cavity, in which water-equivalent or bone-like solid blocks can be inserted. The irradiated phantom was scanned with an magnetic resonance imaging (MRI) scanner. Dose distributions were obtained by calibrating the polymer gel for a relationship between the absorbed dose and the spin-spin relaxation rate of the magnetic resistance (MR) signal. To study dose distributions we had to analyze MR imaging artifacts. This was done in three ways: comparison of a measured dose distribution in a simulated homogeneous phantom with a reference dose distribution, comparison of a sagittally scanned image with a sagittal image reconstructed from axially scanned data, and coregistration of MR and computed-tomography images. We found that the MRI artifacts cause a geometrical distortion of less than 2 mm and less than 10% change in the dose around solid inserts. With these limitations in mind we could make some qualitative measurements. Particularly we observed clear differences between the measured dose distributions around an air-gap and around bone-like material for a 6 MV photon beam. In conclusion, the gel dosimetry has the potential to qualitatively characterize the dose distributions near heterogeneities in 3D

  18. Dosimetry as an integral part of radiation processing

    International Nuclear Information System (INIS)

    Zagorski, Z.P.

    1999-01-01

    Different connections between high-dose dosimetry and radiation processing are discussed. Radiation processing cannot be performed without proper dosimetry. Accurate high dose and high dose rate dosimetry exhibits several aspects: first of all it is the preservation of the quality of the product, then fulfillment of legal aspects and last but not the least the safety of processing. Further, seldom discussed topics are as follow: dosimetric problems occurring with double-side EB irradiations, discussed in connection with the deposition of electric charge during electron beam irradiation. Although dosimetry for basic research and for medical purposes are treated here only shortly, some conclusions reached from these fields are considered in dosimetry for radiation processing. High-dose dosimetry of radiation has become a separate field, with many papers published every year, but applied dosimetric projects are usually initiated by a necessity of particular application. (author)

  19. TU-C-BRE-10: A Streamlined Approach to EPID Transit Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Morris, B; Fontenot, J [Louisiana State University, Baton Rouge, LA (United States); Mary Bird Perkins Cancer Center, Baton Rouge, LA (United States)

    2014-06-15

    Purpose: To investigate the feasibility of a simple and efficient transit dosimetry method using the electronic portal imaging device (EPID) for dose delivery error detection and prevention. Methods: In the proposed method, 2D reference transit images are generated for comparison with online images acquired during treatment. Reference transit images are generated by convolving through-air EPID measurements of each field with pixel-specific kernels selected from a library of pre-calculated Monte Carlo pencil kernels of varying radiological thickness. The kernel used for each pixel is selected based on the calculated radiological thickness of the patient along a line joining the pixel and the virtual source. The accuracy of the technique was evaluated in flat homogeneous and heterogeneous plastic water phantoms, a heterogeneous cylindrical phantom, and an anthropomorphic head phantom. Gamma criteria of 3%/3 mm was used to quantify the accuracy of the technique for the various cases. Results: An average of 99.9% and 99.7% of the points in the comparison between the measured and predicted images passed a 3%/3mm gamma for the homogeneous and heterogeneous plastic water phantoms, respectively. 97.1% of the points passed for the analysis of the heterogeneous cylindrical phantom. For the anthropomorphic head phantom, an average of 97.8% of points passed the 3%/3mm gamma criteria for all field sizes. Failures were observed primarily in areas of drastic thickness or material changes and at the edges of the fields. Conclusion: The data suggest that the proposed transit dosimetry method is a feasible approach to in vivo dose monitoring. Future research efforts could include implementation for more complex fields and sensitivity testing of the method to setup errors and changes in anatomy. Oncology Data Systems provided partial funding support but did not participate in the collection or analysis of data.

  20. The work programme of EURADOS on internal and external dosimetry.

    Science.gov (United States)

    Rühm, W; Bottollier-Depois, J F; Gilvin, P; Harrison, R; Knežević, Ž; Lopez, M A; Tanner, R; Vargas, A; Woda, C

    2018-01-01

    Since the early 1980s, the European Radiation Dosimetry Group (EURADOS) has been maintaining a network of institutions interested in the dosimetry of ionising radiation. As of 2017, this network includes more than 70 institutions (research centres, dosimetry services, university institutes, etc.), and the EURADOS database lists more than 500 scientists who contribute to the EURADOS mission, which is to promote research and technical development in dosimetry and its implementation into practice, and to contribute to harmonisation of dosimetry in Europe and its conformance with international practices. The EURADOS working programme is organised into eight working groups dealing with environmental, computational, internal, and retrospective dosimetry; dosimetry in medical imaging; dosimetry in radiotherapy; dosimetry in high-energy radiation fields; and harmonisation of individual monitoring. Results are published as freely available EURADOS reports and in the peer-reviewed scientific literature. Moreover, EURADOS organises winter schools and training courses on various aspects relevant for radiation dosimetry, and formulates the strategic research needs in dosimetry important for Europe. This paper gives an overview on the most important EURADOS activities. More details can be found at www.eurados.org .

  1. Foundations of ionizing radiation dosimetry

    International Nuclear Information System (INIS)

    Denisenko, O.N.; Pereslegin, I.A.

    1985-01-01

    Foundations of dosimetry in application to radiotherapy are presented. General characteristics of ionizing radiations and main characteristics of ionizing radiation sources, mostly used in radiotherapy, are given. Values and units for measuring ionizing radiation (activity of a radioactive substance, absorbed dose, exposure dose, integral dose and dose equivalent are considered. Different methods and instruments for ionizing radiation dosimetry are discussed. The attention is paid to the foundations of clinical dosimetry (representation of anatomo-topographic information, choice of radiation conditions, realization of radiation methods, corrections for a configuration and inhomogeneity of a patient's body, account of biological factors of radiation effects, instruments of dose field formation, control of irradiation procedure chosen)

  2. Prediction of DVH parameter changes due to setup errors for breast cancer treatment based on 2D portal dosimetry

    International Nuclear Information System (INIS)

    Nijsten, S. M. J. J. G.; Elmpt, W. J. C. van; Mijnheer, B. J.; Minken, A. W. H.; Persoon, L. C. G. G.; Lambin, P.; Dekker, A. L. A. J.

    2009-01-01

    Electronic portal imaging devices (EPIDs) are increasingly used for portal dosimetry applications. In our department, EPIDs are clinically used for two-dimensional (2D) transit dosimetry. Predicted and measured portal dose images are compared to detect dose delivery errors caused for instance by setup errors or organ motion. The aim of this work is to develop a model to predict dose-volume histogram (DVH) changes due to setup errors during breast cancer treatment using 2D transit dosimetry. First, correlations between DVH parameter changes and 2D gamma parameters are investigated for different simulated setup errors, which are described by a binomial logistic regression model. The model calculates the probability that a DVH parameter changes more than a specific tolerance level and uses several gamma evaluation parameters for the planning target volume (PTV) projection in the EPID plane as input. Second, the predictive model is applied to clinically measured portal images. Predicted DVH parameter changes are compared to calculated DVH parameter changes using the measured setup error resulting from a dosimetric registration procedure. Statistical accuracy is investigated by using receiver operating characteristic (ROC) curves and values for the area under the curve (AUC), sensitivity, specificity, positive and negative predictive values. Changes in the mean PTV dose larger than 5%, and changes in V 90 and V 95 larger than 10% are accurately predicted based on a set of 2D gamma parameters. Most pronounced changes in the three DVH parameters are found for setup errors in the lateral-medial direction. AUC, sensitivity, specificity, and negative predictive values were between 85% and 100% while the positive predictive values were lower but still higher than 54%. Clinical predictive value is decreased due to the occurrence of patient rotations or breast deformations during treatment, but the overall reliability of the predictive model remains high. Based on our

  3. Liulin-type spectrometry-dosimetry instruments

    International Nuclear Information System (INIS)

    Dachev, T.; Dimitrov, P.; Tomov, B.; Matviichuk, Y.; Spurny, F.; Ploc, O.; Brabcova, K.; Jadrnickova, I.

    2011-01-01

    The main purpose of Liulin-type spectrometry-dosimetry instruments (LSDIs) is cosmic radiation monitoring at the workplaces. An LSDI functionally is a low mass, low power consumption or battery-operated dosemeter. LSDIs were calibrated in a wide range of radiation fields, including radiation sources, proton and heavy-ion accelerators and CERN-EC high-energy reference field. Since 2000, LSDIs have been used in the scientific programmes of four manned space flights on the American Laboratory and ESA Columbus modules and on the Russian segment of the International Space Station, one Moon spacecraft and three spacecraft around the Earth, one rocket, two balloons and many aircraft flights. In addition to relative low price, LSDIs have proved their ability to qualify the radiation field on the ground and on the above-mentioned carriers. (authors)

  4. Internal in vitro dosimetry for fish using hydroxyapatite-based EPR detectors

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov, D.V. [Urals Division of Russian Academy of Sciences, Institute of Metal Physics, Yekaterinburg (Russian Federation); Ural Federal University, Yekaterinburg (Russian Federation); Shishkina, E.A.; Osipov, D.I.; Pryakhin, E.A. [Urals Research Center for Radiation Medicine, Chelyabinsk (Russian Federation); Razumeev, R.A. [Ural Federal University, Yekaterinburg (Russian Federation)

    2015-08-15

    A number of aquatic ecosystems were exposed to ionizing radiation as a result of the activities of the Mayak Production Association in the Southern Urals, former Soviet Union, in the 1950s. Currently, fishes inhabiting contaminated lakes are being actively studied. These investigations need dosimetric support. In the present paper the results of a pilot study for elaborating an EPR dosimeter which can be used for internal dosimetry in vitro are described. Biological hydroxyapatite is proposed here to be used as a detecting substance. More specifically, small hydroxyapatite grains are proposed for use as point detectors fixed in a solid matrix. After having been pelletized, the detectors were covered by Mylar and placed in the body of a fish to be stored in the fridge for several months. Application of the detectors for internal fish dosimetry demonstrated that the enamel sensitivity is sufficient for passive detection of ionizing radiation in fishes inhabiting contaminated lakes in the Southern Urals. (orig.)

  5. Radiation protection - Performance criteria for service laboratories performing biological dosimetry by cytogenetics

    International Nuclear Information System (INIS)

    2004-01-01

    This International Standard provides criteria for quality assurance and quality control, evaluation of the performance and the accreditation of biological dosimetry by cytogenetic service laboratories. This International Standard addresses: a) the confidentiality of personal information, for the customer and the service laboratory, b) the laboratory safety requirements, c) the calibration sources and calibration dose ranges useful for establishing the reference dose-effect curves allowing the dose estimation from chromosome aberration frequency, and the minimum detection levels, d) the scoring procedure for unstable chromosome aberrations used for biological dosimetry, e) the criteria for converting a measured aberration frequency into an estimate of absorbed dose, f) the reporting of results, g) the quality assurance and quality control, h) informative annexes containing examples of a questionnaire, instructions for customers, a data sheet for recording aberrations and a sample report

  6. Suitability of Israeli Household Salt for Retrospective Dosimetry

    International Nuclear Information System (INIS)

    Datz, H.; Druzhyna, S.; Oster, L.; Orion, I.; Darras, I.; Hershkovich, D.; Horowitz, Y.

    2014-01-01

    Following a nuclear accident or a terror attack involving the dispersal of radioactive material, radiation dose assessment to first responders and the members of the public is essential. This information may be used by medical personnel to decide whether to refer the exposed individual for medical treatment or not. Few people, if any, will be wearing standard dosimeters at the exposure scene, so the need for a retrospective assessment of the radiation dose is an acute necessity. Previously developed methods for retrospective dosimetry (RD) have suggested various types of materials such as tiles, bricks, CDs, electronic components, mobile phones, electron paramagnetic resonance of tooth enamel, hair, nails, biological dosimetry techniques etc. These techniques involve significant disadvantages such as: the long time required to prepare the samples for measurement the considerable expense of the measuring equipment, invasive procedure and others. The need for an RD technique which will be fast, inexpensive, reliable, non-invasive and, if possible, portable, remains an on-going challenge. The ideal retrospective dosimeter must fulfill the following basic criteria: a) Availability in the contaminated area, b) Adequate dose measurement capability in the relevant range of dose levels, c) Negligible or known fading between exposure and measurement

  7. Thermoluminescence in medical dosimetry; Termoluminiscencia en dosimetria medica

    Energy Technology Data Exchange (ETDEWEB)

    Rivera, T., E-mail: trivera@ipn.mx [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Av. Legaria 694, Col. Irrigacion, 11500 Mexico D. F. (Mexico)

    2011-10-15

    The dosimetry by thermoluminescence (Tl) is applied in the entire world for the dosimetry of ionizing radiations specially to personal and medical dosimetry. This dosimetry method has been very interesting for measures in vivo because the Tl dosimeters have the advantage of being very sensitive in a very small volume and they are also equivalent to tissue and they do not need additional accessories (for example, cable, electrometer, etc.) The main characteristics of the diverse Tl materials to be used in the radiation measures and practical applications are: the Tl curve, the share homogeneity, the signal stability after the irradiation, precision and exactitude, the response in function with the dose and the energy influence. In this work a brief summary of the advances of the radiations dosimetry is presented by means of the thermally stimulated luminescence and its application to the dosimetry in radiotherapy. (Author)

  8. Radiochromic film dosimetry

    International Nuclear Information System (INIS)

    Soares, Christopher G.

    2006-01-01

    The object of this paper is to give a new user some practical information on the use of radiochromic films for medical applications. While various aspects of radiochromic film dosimetry for medical applications have been covered in some detail in several other excellent review articles which have appeared in the last few years [Niroomand-Rad, A., Blackwell, C.R., Coursey, B.M., Gall, K.P., McLaughlin, W.L., Meigooni, A.S., Nath, R., Rodgers, J.E., Soares, C.G., 1998. Radiochromic dosimetry: recommendations of the AAPM Radiation Therapy Committee Task Group 55. Med. Phys. 25, 2093-2115; Dempsey, J.F., Low, D.A., Mutic, S., Markman, J., Kirov, A.S., Nussbaum, G.H., Williamson, J.F., 2000. Validation of a precision radiochromic film dosimetry system for quantitative two-dimensional imaging of acute exposure dose distributions. Med. Phys. 27, 2462-2475; Butson, M.J., Yu, P.K.N., Cheung, T., Metcalfe, P., 2003. Radiochromic film for medical radiation dosimetry. Mater. Sci. Eng. R41, 61-120], it is the intent of the present author to present material from a more user-oriented and practical standpoint. That is, how the films work will be stressed much less than how to make the films work well. The strength of radiochromic films is most evident in applications where there is a very high dose gradient and relatively high absorbed dose rates. These conditions are associated with brachytherapy applications, measurement of small fields, and at the edges (penumbra regions) of larger fields

  9. Effect of processor temperature on film dosimetry

    International Nuclear Information System (INIS)

    Srivastava, Shiv P.; Das, Indra J.

    2012-01-01

    Optical density (OD) of a radiographic film plays an important role in radiation dosimetry, which depends on various parameters, including beam energy, depth, field size, film batch, dose, dose rate, air film interface, postexposure processing time, and temperature of the processor. Most of these parameters have been studied for Kodak XV and extended dose range (EDR) films used in radiation oncology. There is very limited information on processor temperature, which is investigated in this study. Multiple XV and EDR films were exposed in the reference condition (d max. , 10 × 10 cm 2 , 100 cm) to a given dose. An automatic film processor (X-Omat 5000) was used for processing films. The temperature of the processor was adjusted manually with increasing temperature. At each temperature, a set of films was processed to evaluate OD at a given dose. For both films, OD is a linear function of processor temperature in the range of 29.4–40.6°C (85–105°F) for various dose ranges. The changes in processor temperature are directly related to the dose by a quadratic function. A simple linear equation is provided for the changes in OD vs. processor temperature, which could be used for correcting dose in radiation dosimetry when film is used.

  10. DRDC Ottawa working standard for biological dosimetry

    International Nuclear Information System (INIS)

    Segura, T.M.; Prud'homme-Lalonde, L.; Thorleifson, E.; Lachapelle, S.; Mullins, D.; Qutob, S.; Wilkinson, D.

    2005-07-01

    This Standard provides quality assurance, quality control, and evaluation of the performance criteria for the purpose of accreditation of the Radiation Biology laboratory at Defence Research and Development Canada - Ottawa (DRDC Ottawa) using biological dosimetry to predict radiation exposure doses. The International Standard (ISO 19238) and the International Atomic Energy Association (IAEA) Technical Report Series No. 405 are used as guiding documents in preparation of this working document specific to the DRDC Ottawa Radiation Biology Laboratory. This Standard addresses: 1. The confidentiality of personal information, for the customer and the service laboratory; 2. The laboratory safety requirements; 3. The calibration sources and calibration dose ranges useful for establishing the reference dose-effect curves allowing the dose estimation from chromosome aberration frequency, and the minimum detection levels; 4. Transportation criteria for shipping of test samples to the laboratory; 5. Preparation of samples for analysis; 6. The scoring procedure for unstable chromosome aberrations used for biological dosimetry; 7. The criteria for converting a measured aberration frequency into an estimate of absorbed dose; 8. The reporting of results; 9. The quality assurance and quality control plan for the laboratory; and 10. Informative annexes containing examples of a questionnaire, instructions for customers, a data sheet for recording aberrations, a sample report and other supportive documents. (author)

  11. DRDC Ottawa working standard for biological dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Segura, T M; Prud' homme-Lalonde, L [Defence Research and Development Canada, Ottawa, Ontario (Canada); Thorleifson, E [Health Canada, Gatineau, Quebec (Canada); Lachapelle, S; Mullins, D [JERA Consulting (Canada); Qutob, S [Health Canada, Gatineau, Quebec (Canada); Wilkinson, D

    2005-07-15

    This Standard provides quality assurance, quality control, and evaluation of the performance criteria for the purpose of accreditation of the Radiation Biology laboratory at Defence Research and Development Canada - Ottawa (DRDC Ottawa) using biological dosimetry to predict radiation exposure doses. The International Standard (ISO 19238) and the International Atomic Energy Association (IAEA) Technical Report Series No. 405 are used as guiding documents in preparation of this working document specific to the DRDC Ottawa Radiation Biology Laboratory. This Standard addresses: 1. The confidentiality of personal information, for the customer and the service laboratory; 2. The laboratory safety requirements; 3. The calibration sources and calibration dose ranges useful for establishing the reference dose-effect curves allowing the dose estimation from chromosome aberration frequency, and the minimum detection levels; 4. Transportation criteria for shipping of test samples to the laboratory; 5. Preparation of samples for analysis; 6. The scoring procedure for unstable chromosome aberrations used for biological dosimetry; 7. The criteria for converting a measured aberration frequency into an estimate of absorbed dose; 8. The reporting of results; 9. The quality assurance and quality control plan for the laboratory; and 10. Informative annexes containing examples of a questionnaire, instructions for customers, a data sheet for recording aberrations, a sample report and other supportive documents. (author)

  12. Analysis of SCRM experience in the area of quality assurance for retrospective EPR dosimetry technique with teeth

    International Nuclear Information System (INIS)

    Sholom, S. V.; Chumak, V.V.

    2003-01-01

    EPR dosimetry with tooth enamel is commonly accepted as one of most precise and accurate methods for retrospective dosimetry. At the same time, regularly conducted international Intercomparisons and Inter-calibrations of EPR dosimetry techniques demonstrate the significant scatter of results among laboratories operation in this area. This is mainly caused by the lack of commonly adopted unified technique which would be based on clear and efficient scheme of quality assurance. In the present work we will summarize more than ten-year experience of Scientific Center for Radiation Medicine in the area of EPR dosimetry from the point of view of quality assurance. EPR dosimetry technique with teeth, which was developed and being used in SCRM for routine dosimetry of liquidators is characterized by two-level system of quality assurance. In-house level covers all steps of the technique and allows control and minimizing of uncertainties that arise on separate steps. Extramural level provides the control of reliability and accuracy of technique in whole by means of regular participation in bi- and multi-lateral intercomparisons. Cumulative uncertainty of EPR dosimetry technique determined based on the results of 6 different intercomparisons is 21 mGy for dose below 300 and 11% for dose higher that 300 mGy. (authors)

  13. Performing personnel dosimetry investigations and records quality assurance

    International Nuclear Information System (INIS)

    Perle, S.C.

    2002-01-01

    Radiation Safety Officers (RSOs) sometimes face situations in which personnel dosimetry estimates are required after dosimeters issued to radiation workers (film or TLD badges, extremity dosimeters, etc.) are lost or damaged before processing. This article was prepared to help those involved with personnel dosimetry investigations became aquatinted with this process. A factor that contributes to the anxiety of those unfamiliar with dosimetry investigations is the lack of published guidance available in this subject. More printed resources are needed to help radiation safety professionals familiarize themselves and understand personnel dosimetry investigations. Topics discussed in this presentation include the justification of performing dosimetry investigations, recommendations on how to perform them and the advantages of performing such investigations

  14. Dosimetry and Shielding of X and Gamma Radiation

    International Nuclear Information System (INIS)

    Oncescu, M.; Panaitescu, I.

    1992-01-01

    This book covers the following problems: 1. X and Gamma radiations, 2. Interaction of X-ray and gamma radiations with matter, 3. Interaction of electrons with matter, 4. Principles and basic concepts of dosimetry, 5. Ionization dosimetry, 6. Calorimetric chemical and photographic dosimetry, 7. Solid state dosimetry, 8. Computation of dosimetric quantities, 9. Dosimetry in radiation protection, 10. Shielding of X and gamma radiations. The authors, well-known Romanian experts in Radiation Physics and Engineering, gave an up-dated, complete and readable account of this subject matter. The analyses of physical principles and concepts, of materials and instruments and of computational methods and applications are all well balanced to meat the needs of a broad readership

  15. Simulation of the spherical experimental assemblies for the mixed neutron-gamma reference fields implementation

    International Nuclear Information System (INIS)

    Kluson, J.; Jansky, B.

    2009-01-01

    Reference mixed neutron-gamma fields are used for test and calibration of dosimetric and spectrometric systems, intercomparison measurements, and benchmark tests and represent experimental base for reactor studies. Set of the spherical experimental assemblies for the mixed neutron-gamma reference fields implementation was build in the NRI Rez. Extended sets of measurements and simulation calculations were done to describe the reference mixed field dosimetry and spectral characteristics with best achievable precision. The Monte Carlo technique was used for different experimental setups models description, comparison and verification and field characteristics simulation. Effects (hardly distinguishable experimentally) were also studied ( contributions from individual parts of experimental setup, field individual components and next effects as shadow shield cones transparency, etc.). Some results and main conclusions of these studies and calculations are presented and discussed. (authors)

  16. Simulation of the spherical experimental assemblies for the mixed neutron-gamma reference fields implementation

    International Nuclear Information System (INIS)

    Kluson, J.; Jansky, B.

    2008-01-01

    Reference mixed neutron-gamma fields are used for test and calibration of dosimetric and spectrometric systems, intercomparison measurements, and benchmark tests and represent experimental base for reactor studies. Set of the spherical experimental assemblies for the mixed neutron-gamma reference fields implementation was build in the NRI Rez. Extended sets of measurements and simulation calculations were done to describe the reference mixed field dosimetry and spectral characteristics with best achievable precision. The Monte Carlo technique was used for different experimental setups models description, comparison and verification and field characteristics simulation. Effects (hardly distinguishable experimentally) were also studied ( contributions from individual parts of experimental setup, field individual components and next effects as shadow shield cones transparency, etc.). Some results and main conclusions of these studies and calculations are presented and discussed. (authors)

  17. Updating the INDAC computer application of internal dosimetry

    International Nuclear Information System (INIS)

    Bravo Perez-Tinao, B.; Marchena Gonzalez, P.; Sollet Sanudo, E.; Serrano Calvo, E.

    2013-01-01

    The initial objective of this project is to expand the application INDAC currently used in internal dosimetry services of the Spanish nuclear power plants and Tecnatom for estimating the effective doses of internal dosimetry of workers in direct action. or in-vivo dosimetry. (Author)

  18. Dosimetry methods

    DEFF Research Database (Denmark)

    McLaughlin, W.L.; Miller, A.; Kovacs, A.

    2003-01-01

    Chemical and physical radiation dosimetry methods, used for the measurement of absorbed dose mainly during the practical use of ionizing radiation, are discussed with respect to their characteristics and fields of application....

  19. Consistency between data from the ENDF/B-V dosimetry file and corresponding experimental data for some fast neutron reference spectra

    International Nuclear Information System (INIS)

    Nolthenius, H.J.; Zijp, W.L.

    1981-11-01

    Results are given of a study on the consistency between 'integral' and 'differential' cross sections data for four benchmark neutron spectra and 36 neutron reactions of importance for reactor neutron metrology. The energy dependent cross section data and their uncertainty data are obtained from the ENDF/B-V dosimetry file. The reactions have been considered with respect to the following quantities: 1. the precision of the averaged cross sections, for a specified spectrum; 2. the discrepancy between the measured and the calculated average cross section values; 3. the consistency between the measured and calculated average cross section values, described by the chi 2 -parameter. It was possible to take into account the available cross section covariance information present in the ENDF/B-V dosimetry file. Covariance information on the benchmark flux density spectra was not taken into account in this study

  20. Results of the ninth exercise of intercomparison in services of personal dosimetry in Argentina Republic in the year of 2011

    International Nuclear Information System (INIS)

    Ferrufino, G.A.; Discacciatti, P.A.; Lopez, F.O.

    2013-01-01

    In this paper we present the results of the ninth intercomparison exercise personal dosimetry services, conducted by the Nuclear Regulatory Authority in 2011. The exercise was designed to evaluate the performance of laboratories providing personal dosimetry services in Argentina , for X-rays and gamma radiation fields . This exercise was organized by the Nuclear Regulatory Authority with the Ministry of Health of the Nation and the Regional Reference Laboratory Centre for Dosimetry of the National Atomic Energy Commission . The irradiations were carried out in full accordance with ISO 4037-3 . Participates all private companies in Argentina serving all personal dosimetry laboratories and agencies, provincial and national. Furthermore, the Laboratories from Cuba, Brazil and Uruguay also participate. The performance of a laboratory is considered acceptable if it meets the criteria established in the IRAM- ISO 14146 , which states: 'It is recognized that at most, one-tenth of dosimeters irradiated to exceed the limits'. Of all of the laboratories that participated , 68% reported their results within the acceptance criteria above. The primary objective of this intercomparison exercise is to provide an objective tool to evaluate the ability of personnel dosimetry services. (author)

  1. Radiation dosimetry in nuclear medicine

    International Nuclear Information System (INIS)

    Stabin, M.G.; Tagesson, M.; Ljungberg, M.; Strand, S.E.; Thomas, S.R.

    1999-01-01

    Radionuclides are used in nuclear medicine in a variety of diagnostic and therapeutic procedures. A knowledge of the radiation dose received by different organs in the body is essential to an evaluation of the risks and benefits of any procedure. In this paper, current methods for internal dosimetry are reviewed, as they are applied in nuclear medicine. Particularly, the Medical Internal Radiation Dose (MIRD) system for dosimetry is explained, and many of its published resources discussed. Available models representing individuals of different age and gender, including those representing the pregnant woman are described; current trends in establishing models for individual patients are also evaluated. The proper design of kinetic studies for establishing radiation doses for radiopharmaceuticals is discussed. An overview of how to use information obtained in a dosimetry study, including that of the effective dose equivalent (ICRP 30) and effective dose (ICRP 60), is given. Current trends and issues in internal dosimetry, including the calculation of patient-specific doses and in the use of small scale and microdosimetry techniques, are also reviewed

  2. An IAEA Survey of Dosimetry Audit Networks for Radiotherapy

    International Nuclear Information System (INIS)

    Grochowska, Paulina; Izewska, Joanna

    2013-01-01

    A Survey: In 2010, the IAEA undertook a task to investigate and review the coverage and operations of national and international dosimetry audit programmes for radiotherapy. The aim was to organize the global database describing the activities of dosimetry audit networks in radiotherapy. A dosimetry audit questionnaire has been designed at an IAEA consultants' meeting held in 2010 for organizations conducting various levels of dosimetry audits for radiotherapy. Using this questionnaire, a survey was conducted for the first time in 2010 and repeated in 2011. Request for information on different aspects of the dosimetry audit was included, such as the audit framework and resources, its coverage and scope, the dosimetry system used and the modes of audit operation, i.e. remotely and through on-site visits. The IAEA questionnaire was sent to over 80 organizations, members of the IAEA/WHO Network of Secondary Standards Dosimetry Laboratories (SSDLs) and other organizations known for having operated dosimetry audits for radiotherapy in their countries or internationally. Survey results and discussion: In response to the IAEA survey, 53 organizations in 45 countries confirmed that they operate dosimetry audit services for radiotherapy. Mostly, audits are conducted nationally, however there are five organizations offering audits abroad, with two of them operating in various parts of the world and three of them at the regional level, auditing radiotherapy centres in neighbouring countries. The distribution of dosimetry audit services in the world is given. (author)

  3. Personnel neutron dosimetry at Department of Energy facilities

    International Nuclear Information System (INIS)

    Brackenbush, L.W.; Endres, G.W.R.; Selby, J.M.; Vallario, E.J.

    1980-08-01

    This study assesses the state of personnel neutron dosimetry at DOE facilities. A survey of the personnel dosimetry systems in use at major DOE facilities was conducted, a literature search was made to determine recent advances in neutron dosimetry, and several dosimetry experts were interviewed. It was concluded that personnel neutron dosimeters do not meet current needs and that serious problems exist now and will increase in the future if neutron quality factors are increased and/or dose limits are lowered

  4. High-accuracy dosimetry study for intensity-modulated radiation therapy(IMRT) commissioning

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Hae Sun

    2010-02-15

    % to 7% (0.5 x 0.5 cm{sup 2}). In addition, a method using a pixel-based unfolding curve was developed and applied to correct the non-uniform response of flat-bed type scanners for a radiochromic film. Also, the accuracy of the method was finally evaluated by comparing the results with those of an ion chamber, Monte Carlo simulation, and CF-based conventional method. For individual dose, the dosimetric error of using conventional method and using the pixel-based unfolding curve was reduced to less than 3%, and 1%, respectively. In case of step-wise doses, the average difference of 16% with MC calculation was reduced up to 1% by using the correction method in this study. Consequently, the accuracy of dose computation algorithms in TPS can be evaluated by the developed LEGO-type solid phantom, small filed dosimetry, the correction method for non-uniform response of scanners. It is also recognized that the developed hardware and software which are possible to be used for QA procedure are very reliable and they could be used for reference study of other radiation therapies

  5. Internal dosimetry hazard and risk assessments: methods and applications

    International Nuclear Information System (INIS)

    Roberts, G.A.

    2006-01-01

    Routine internal dose exposures are typically (in the UK nuclear industry) less than external dose exposures: however, the costs of internal dosimetry monitoring programmes can be significantly greater than those for external dosimetry. For this reason decisions on when to apply routine monitoring programmes, and the nature of these programmes, can be more critical than for external dosimetry programmes. This paper describes various methods for performing hazard and risk assessments which are being developed by RWE NUKEM Limited Approved Dosimetry Services to provide an indication when routine internal dosimetry monitoring should be considered. (author)

  6. Radiation protection dosimetry in medicine - Report of the working group n.9 of the European radiation dosimetry group (EURADOS) - coordinated network for radiation dosimetry (CONRAD - contract EC N) fp6-12684; Dosimetrie pour la radioprotection en milieu medical - rapport du groupe de travail n. 9 du European radiation dosimetry group (EURADOS) - coordinated netword for radiation dosimetry (CONRAD - contrat CE fp6-12684)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-07-01

    This report present the results achieved within the frame of the work the WP 7 (Radiation Protection Dosimetry of Medical Staff) of the coordination action CONRAD (Coordinated Network for Radiation Dosimetry) funded through the 6. EU Framework Program. This action was coordinated by EURADOS (European Radiation Dosimetry Group). EURADOS is an organization founded in 1981 to advance the scientific understanding and the technical development of the dosimetry of ionising radiation in the fields of radiation protection, radiobiology, radiation therapy and medical diagnosis by promoting collaboration between European laboratories. WP7 coordinates and promotes European research for the assessment of occupational exposures to staff in therapeutic and diagnostic radiology workplaces. Research is coordinated through sub-groups covering three specific areas: 1. Extremity dosimetry in nuclear medicine and interventional radiology: this sub-group coordinates investigations in the specific fields of the hospitals and studies of doses to different parts of the hands, arms, legs and feet; 2. Practice of double dosimetry: this sub-group reviews and evaluates the different methods and algorithms for the use of dosemeters placed above and below lead aprons in large exposure during interventional radiology procedures, especially to determine effective doses to cardiologists during cardiac catheterization; and 3. Use of electronic personal dosemeters in interventional radiology: this sub-group coordinates investigations in laboratories and hospitals, and intercomparisons with passive dosemeters with the aim to enable the formulation of standards. (authors)

  7. EURADOS. A success story for European cooperation in the dosimetry of ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Ruehm, Werner [Helmholtz Zentrum Muenchen, Neuherberg (Germany). German Research Center for Environmental Health (GMBH); Schuhmacher, Helmut [Physikalisch-Technische Bundesanstalt, Braunschweig (Germany)

    2017-10-01

    EURADOS (European Radiation Dosimetry Group) is a European research platform aiming at the promotion of research and development and European cooperation in the field of the dosimetry of ionizing radiation (www.eurados.org). Initially founded in 1982, it was established in 2008 as a non-profit registered society under German law and is currently based in Neuherberg, Germany.

  8. Radiographic film orientation in radiotherapy dosimetry

    International Nuclear Information System (INIS)

    Suchowerska, N.; Davison, A.; Drew, J.; Metcalfe, P.

    1996-01-01

    Since the discovery of x-rays, film has been used as a detection medium for radiation. More recently radiographic film has become established as a practical tool for the measurement of dose distribution in radiotherapy. The accuracy and reproducibility of film dosimetry depends on photon energy, processing conditions and film plane orientation. The relationship between photon energy, processing conditions and film dosimetry accuracy has been studied. The role of film plane orientation is still controversial. The current work aims to clarify the effects film plane orientation has on film dosimetry. Poster 205. (author)

  9. The personal dosimetry in Mexico

    International Nuclear Information System (INIS)

    Salazar, M.A.

    2006-01-01

    The Personal Dosimetry in Mexico, has an approximately 30 year-old history; and it had been and it is at the moment, one of the more important resources with which the personnel that works with ionizing radiation sources counts for its protection. The Personal Dosimetry begins with the film dosimetry, technique that even continues being used at the present time by some users, and the main reason of its use is for economic reasons. At the moment this technique, it has been surpassed, by the Thermoluminescent dosimetry, which has taken a lot of peak, mainly by the technological development with which it is counted at the present time; what has given as a result that this technique becomes tip technology; that supported in the characteristic of the used materials, as the handling and processing of the information associated with the new PC, digitizer cards, software etc, what has allowed increases it potential. In this work the current necessities of the market are presented as well as an analysis of the future real necessities in Mexico, at national level, the companies that provide this service and that they spread to satisfy this necessity of the market, including the different used technologies are also mentioned. The application ranges, at the same time, of the advantages and disadvantages of the different systems of Personal Dosimetry in the market. The companies that at the moment provide the service of Personal Dosimetry, its use materials and equipment in indistinct form, for the monitoring of gamma radiation, beta particles, different qualities of x-ray radiation, and sometimes neutrons. The monitoring of the exposed personnel at the diverse sources of ionizing radiation mentioned is carried out in many occasions without having with the materials (detectors), neither the appropriate infrastructure and therefore without the quality control that guarantees a correct evaluation of the dose equivalent, as a result of the exposure to the ionizing radiations; it

  10. Eleventh ORNL personnel dosimetry intercomparison study, May 22-23, 1985

    International Nuclear Information System (INIS)

    Swaja, R.E.; Oyan, R.; Sims, C.S.

    1986-07-01

    The Eleventh Personnel Dosimetry Intercomparison Study was conducted at the Oak Ridge National Laboratory (ORNL) during May 22-23, 1985. Dosimeter badges from 44 participating organizations were mounted on Lucite block phantoms and exposed to four mixed-radiation fields with neutron dose equivalents around 5 mSv and gamma dose equivalents between 0.1 and 0.7 mSv. Results of this study indicated that no participants had difficulty obtaining measurable indication of neutron exposure at the provided dose equivalent levels, and very few had difficulty obtaining indication of gamma exposure at dose equivalents as low as 0.10 mSv. Average neutron results for all dosimeter types were within 20% of reference values with no obvious spectrum dependence. Different dosimeter types (albedo, direct interaction TLD, film, recoil track, and combination albedo-track) with 10 or more reported measurements provided average results within 35% of reference values for all spectra. With regard to precision, about 80% of the reported neutron results had single standard deviations within 10% at the means which indicates that precision is not a problem relative to accuracy for most participants. Average gamma results were greater than reference values by factors of 1.07 to 1.52 for the four exposures with TLD systems being more accurate than film. About 80% of all neutron results and 67% of all gamma results met regulatory standards for measurement accuracy and approximately 70% of all neutron data satisfied national dosimetry accreditation criteria for accuracy plus precision. In general, neutron dosimeter performance observed in this intercomparison was much improved compared to that observed in the prior studies while gamma dosimeter performance was about the same

  11. On line CALDose{sub X}: real time Monte Carlo calculation via Internet for dosimetry in radiodiagnostic; CALDose{sub X} online: Calculos de Monte Carlo em tempo real via Internet para dosimetria em radiodiagnostico

    Energy Technology Data Exchange (ETDEWEB)

    Kramer, Richard; Cassola, Vagner Ferreira; Lira, Carlos Alberto Brayner de Oliveira; Khoury, Helen Jamil, E-mail: rkramer@uol.com.b, E-mail: vagner.cassola@gmail.co [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear; Cavalcanti, Arthur; Lins, Rafael Dueire, E-mail: rdl@ufpe.b [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Centro de Tecnologia e Geociencias. Dept. de Eletronica e Sistemas

    2011-10-26

    The CALDose{sub X} 4.1 is a software which uses thr MASH and FASH phantoms. Patient dosimetry with reference phantoms is limited because the results can be applied only for patients which possess the same body mass and right height that the reference phantom. In this paper, the dosimetry of patients for diagnostic with X ray was extended by using a series of 18 phantoms with defined gender, different body masses and heights, in order to cover the real anatomy of the patients. It is possible to calculate absorbed doses in organs and tissues by real time Monte Carlo dosimetry through the Internet through a dosimetric service called CALDose{sub X} on line

  12. Clinical implementation of a quality assurance program in HDR brachytherapy by in vivo dosimetry with diodes

    International Nuclear Information System (INIS)

    Alecu, R.; Feldmeier, J.J.; Court, W.S.; Alecu, M.; Orton, C.G.

    1996-01-01

    Despite the possibilities of in vivo dosimetry with diodes (e.g. control of dose to organs at risk, recorded confirmational measurements of the dose actually delivered, check of the whole treatment chain, avoidance of misadministrations, etc.) and the fact that it has proven to be very useful as part of a departmental QA program in external beam therapy, few attempts to implement it for HDR brachytherapy procedures have been reported. The reason for this is probably that there are significant technical challenges that must be met prior to its clinical use. The purpose of this study is to investigate the practicability and usefulness of dose measurements for brachytherapy patients in daily clinical practice. In our clinic a high precision patient dosimetry method has been developed, based on the use of silicon diodes. First, calibration factors have been determined under 'reference' irradiation conditions. Secondly, correction factors have been evaluated for situations deviating from the reference conditions, i.e. for different distances from the implanted sources, tissue heterogeneities, presence of different type of applicators, etc. For certain intracavitary, interstitial and surface mold applications this procedure has proven to be sufficiently accurate to allow dose determinations with diodes to be in good agreement with the expected values, i.e. calculated by the treatment planning system (VariSource unit) and checked by ion chamber measurements. The results of in vivo measurements are discussed along with the possibilities and limitations of the employed techniques

  13. Research Laboratory of Mixed Radiation Dosimetry

    International Nuclear Information System (INIS)

    2002-01-01

    Full text: Two main topics of the research work in the Laboratory of Mixed Radiation Dosimetry in 2001 were: development of recombination methods for dosimetry of mixed radiation fields and maintenance and development of unique in Poland reference neutron fields. Additionally research project on internal dosimetry were carried out in collaboration with Division of Radiation Protection Service. RECOMBINATION METHODS Recombination methods make use of the fact that the initial recombination of ions in the gas cavity of the ionization chamber depends on local ionization density. The later can be related to linear energy transfer (LET) and provides information on radiation quality of the investigated radiation fields. Another key feature of the initial recombination is that it does not depend of dose rate. Conditions of initial (local) recombination can be achieved in specially designed high pressure tissue-equivalent ionization chambers, called the recombination chambers. They are usually parallel-plate ionization chambers filled with a tissue-equivalent gas mixture under a pressure of order 1 MPa. The spacing between electrodes is of order of millimeters. At larger spacing, the volume recombination limits the maximum dose rate at which the chamber can be properly operated. The output of the chamber is the ionization current (or collected charge) as a function of collecting voltage. All the recombination methods require the measurement of the ionization current (or charge) at least at two values of the collecting voltage applied to the chamber. The highest voltage should provide the conditions close to saturation (but below discharge or multiplication). The ionization current measured at maximum applied voltage is proportional to the absorbed dose, D, (some small corrections for lack of saturation can be introduced when needed). Measurements at other voltages are needed for the determination of radiation quality. The total dose equivalent in a mixed radiation field is

  14. JENDL dosimetry file 99 (JENDL/D-99)

    International Nuclear Information System (INIS)

    Kobayashi, Katsuhei; Iwasaki, Shin

    2002-01-01

    The JENDL Dosimetry File 99 (JENDL/D-99), which is a revised version of the JENDL Dosimetry File 91 (JENDL/D-91), has been compiled and released for the determination of neutron flux and energy spectra. This work was undertaken to remove the inconsistency between the cross sections and their covariances in JENDL/D-91 since the covariances were mainly taken from IRDF-85 although the cross sections were based on JENDL-3. Dosimetry cross sections have been evaluated for 67 reactions on 47 nuclides together with covariances. The cross sections for 34 major reactions and their covariances were simultaneously generated, and the remaining 33 reaction data were mainly taken from JENDL/D-91. Latest measurements were taken into account in the evaluation. The resultant evaluated data are given in the neutron energy region below 20 MeV in both of point-wise and group-wise files in the ENDF-6 format. In order to confirm the reliability of the evaluated data, several integral tests have been carried out: comparisons with average cross sections measured in fission neutron fields, fast/thermal reactor spectra, DT neutron fields and Li(d,n) neutron fields. It was found from the comparisons that the cross sections calculated from JENDL/D-99 are generally in good agreement with the measured data. The contents of JENDL/D-99 and the results of the integral tests are described in this report. All of the dosimetry cross sections are shown in a graphical form in the Appendix. (author)

  15. Dosimetry in diagnostic and interventional radiology - ICRU and IAEA activities

    International Nuclear Information System (INIS)

    Zoetelief, J.; Pernicka, F.

    2002-01-01

    Full text: Main aims of patient dosimetry in diagnostic and interventional radiology are to determine dosimetric quantities for establishment and use of guidance levels or diagnostic reference levels and for comparative risk assessment. In the latter case, the average doses to the organs and tissues at risk should be assessed. Only limited number of measurements serve to potential risk assessment of the examination and intervention. An additional objective of dosimetry in diagnostic and interventional radiology is the assessment of equipment performance. Ionization chambers are the main devices used for dosimetric measurements in diagnostic and interventional radiology but other devices with special properties are also used. Important examples are thermoluminescent detectors (TLDs) and semiconductor detectors. For most dosemeters used in x-ray medical imaging the desired quantity for calibration of dosemeters is the air kerma free-in-air. Calibrations should be made at appropriate radiation qualities, for which recommendations are available for conventional radiology. It is important that the calibrations are traceable to the international measurement system. The uncertainty of dose measurements in medical x-ray imaging, for comparative risk assessments as well as for quality assurance, should not exceed about 7 per cent in terms of the expanded uncertainty using a coverage factor of 2. The dosimetric approaches in general diagnostic radiology, mammography and computed tomography are slightly different, resulting in application specific dosimetric quantities. Consequently, different protocols for patient dosimetry are available for these different purposes. In general diagnostic radiology, various quantities and terminologies have been used for the specification of dose on the central beam axis at the point where the x-ray beam enters the patient (or a phantom representing the patient). These include the exposure at skin entrance (ESE), the input radiation exposure

  16. Report on external occupational dosimetry in Canada

    International Nuclear Information System (INIS)

    1995-12-01

    In light of the new recommendations of the ICRP in Report 60 on dose quantities and dose limits, this working group was set up to examine the implications for external dosimetry in Canada. The operational quantities proposed by the ICRU are discussed in detail with regard to their applicability in Canada. The current occupational dosimetry services available in Canada are described as well as the several performance intercomparisons that have been carried out within the country as well as internationally. Recommendations are given with respect to standards for dosimetry, including accuracy and precision. More practical advice is given on the choice of dosimeter to use for external dosimetry, frequency of monitoring, and who should be monitored. Specific advice is given on the monitoring of pregnant workers and problem of non-uniform irradiation. Accident and emergency dosimetry are dealt with briefly. Suggestions are given regarding record keeping both for employers and for the national dose registry. 48 refs., 6 tabs., 1 fig

  17. Skeletal dosimetry models for alpha-particles for use in molecular radiotherapy

    Science.gov (United States)

    Watchman, Christopher J.

    Molecular radiotherapy is a cancer treatment methodology whereby a radionuclide is combined with a biologically active molecule to preferentially target cancer cells. Alpha-particle emitting radionuclides show significant potential for use in molecular radiotherapy due to the short range of the alpha-particles in tissue and their high rates of energy deposition. Current radiation dosimetry models used to assess alpha emitter dose in the skeleton were developed originally for occupational applications. In medical dosimetry, individual variability in uptake, translocation and other biological factors can result in poor correlation of clinical outcome with marrow dose estimates determined using existing skeletal models. Methods presented in this work were developed in response to the need for dosimetry models which account for these biological and patient-specific factors. Dosimetry models are presented for trabecular bone alpha particle dosimetry as well as a model for cortical bone dosimetry. These radiation transport models are the 3D chord-based infinite spongiosa transport model (3D-CBIST) and the chord-based infinite cortical transport model (CBICT), respectively. Absorbed fraction data for several skeletal tissues for several subjects are presented. Each modeling strategy accounts for biological parameters, such as bone marrow cellularity, not previously incorporated into alpha-particle skeletal dosimetry models used in radiation protection. Using these data a study investigating the variability in alpha-particle absorbed fractions in the human skeleton is also presented. Data is also offered relating skeletal tissue masses in individual bone sites for a range of ages. These data are necessary for dose calculations and have previously only been available as whole body tissue masses. A revised 3D-CBIST model is also presented which allows for changes in endosteum thickness to account for revised target cell location of tissues involved in the radiological

  18. ESR/tooth enamel dosimetry application to Chernobyl case: individual retrospective dosimetry of the liquidators and wild animals

    International Nuclear Information System (INIS)

    Bugai, A.; Baryakchtar, V.G.; Baran, N.

    1996-01-01

    ESR/tooth enamel dosimetry technique was used for individual retrospective dosimetry of the servicemen who had worked in 1986-1987 at the liquidation of consequences of the Chernobyl accident. For 18 investigated cases, the values varied from 0,10 (sensitivity limit) to 1,75 Gy. The same technique was used for individual dosimetry of wild animals boars, red deers, elks) hunted at contaminated 30-km area around the Chernobyl Power Plant. Measured values varied from 0,20 to 5,0 Gy/year and were compared with calculated for external and internal irradiation

  19. An on-site dosimetry audit for high-energy electron beams

    Directory of Open Access Journals (Sweden)

    Leon de Prez

    2018-01-01

    Full Text Available Background and purpose: External dosimetry audits are powerful quality assurance instruments for radiotherapy. The aim of this study was to implement an electron dosimetry audit based on a contemporary code of practice within the requirements for calibration laboratories performing proficiency tests. This involved the determination of suitable acceptance criteria based on thorough uncertainty analyses. Materials and methods: Subject of the audit was the determination of absorbed dose to water, Dw, and the beam quality specifier, R50,dos. Fifteen electron beams were measured in four institutes according to the Belgian-Dutch code of practice for high-energy electron beams. The expanded uncertainty (k = 2 for the Dw values was 3.6% for a Roos chamber calibrated in 60Co and 3.2% for a Roos chamber cross-calibrated against a Farmer chamber. The expanded uncertainty for the beam quality specifier, R50,dos, was 0.14 cm. The audit acceptance levels were based on the expanded uncertainties for the comparison results and estimated to be 2.4%. Results: The audit was implemented and validated successfully. All Dw audit results were satisfactory with differences in Dw values mostly smaller than 0.5% and always smaller than 1%. Except for one, differences in R50,dos were smaller than 0.2 cm and always smaller than 0.3 cm. Conclusions: An electron dosimetry audit based on absorbed dose to water and present-day requirements for calibration laboratories performing proficiency tests was successfully implemented. It proved international traceability of the participants value with an uncertainty better than 3.6% (k = 2. Keywords: Absorbed dose to water, Audit, Code of practice, Dosimetry, Electron beam, Radiation therapy

  20. Utilisation of OSL from table salt in retrospective dosimetry

    International Nuclear Information System (INIS)

    Fujita, Hiroki; Jain, Mayank; Murray, Andrew S.

    2011-01-01

    Common salt (NaCl) has previously been suggested for use in dose estimation in accident dosimetry. In this study, we investigated the optically stimulated luminescence (OSL) and violet thermoluminescence (VTL) characteristics of 'Aji-Shio' (Ajinomoto), a Japanese commercial salt. A comparison of OSL and TL signals allowed identification of common source traps. The initial OSL signal contained a dominant thermally unstable component, which necessitated prior heat treatment. Based on these luminescence characteristics, a single-aliquot regenerative-dose (SAR) OSL protocol was modified and tested. The protocol worked very well for six types of salt, but not for four other types of salt. A minimum detection limit of ∼15 mGy was estimated using the OSL protocol; this is lower than the value obtained from other forms of OSL retrospective dosimetry and lower than that obtained using electron spin resonance (ESR) dosimetry. It was concluded that the OSL from Japanese commercial salt could be used successfully to derive precise estimates of accident dose. (author)

  1. Future developments in etched track detectors for neutron dosimetry

    International Nuclear Information System (INIS)

    Tommasino, L.

    1987-01-01

    Many laboratories engaged in the field of personal neutron dosimetry are interested in developing better etching processes and improving the CR-39 detecting materials. To know how much effort must still be devoted to the development of etch track dosimetry, it is necessary to understand the advantages. limitations and degree of exploitation of the currently available techniques. So much has been learned about the chemical and electrochemical etching processes that an optimised combination of etching processes could make possible the elimination of many of the existing shortcomings. Limitations of etched track detectors for neutron dosimetry arise mainly because the registration occurs only on the detector surface. These damage type detectors are based on radiation induced chain scission processes in polymers, which result in hole-type tracks in solids. The converse approach, yet to be discovered, would be the development of cure-track detectors, where radiation induced cross linking between organic polymer chains could result in solid tracks in liquids. (author)

  2. Dosimetry methods for fuels, cladding and structural materials

    International Nuclear Information System (INIS)

    Roettger, H.

    1980-01-01

    This volume of the proceedings of the symposium on reactor dosimetry covers the following topics: the metallurgy and dosimetry interface, radiation damage correlations of structural materials and damage analyses techniques, dosimetry for fusion materials, light water reactor pressure vessel surveillance in practice and irradiation experiments, fast reactor and reseach reactor characterization

  3. Automated personal dosimetry monitoring system for NPP

    International Nuclear Information System (INIS)

    Chanyshev, E.; Chechyotkin, N.; Kondratev, A.; Plyshevskaya, D.

    2006-01-01

    personal dosimeters (albedo dosimeters). Operational and emergency monitoring of external radiation exposure: - Gamma radiation dose and dose rate measurement using direct reading personal dosimeters. - Gamma radiation dose measurement using radio-photoluminescent personal dosimeters. Monitoring of internal radiation exposure: - Measurement of activity of incorporated radionuclides using whole body counters. Hardware of A.P.D.M.S. represents a complex of automated workplaces based on industrial computers and measuring equipment; all workplaces are connected to one local computational network. Client software installed on automated workplaces processes the results of dosimetry monitoring (spectrum processing, computation of personal dose, report generation, etc.) and provides data exchange with data base of A.P.D.M.S. in the remote server. Communication with A.P.D.M.S. server is organized via the local computational network Ethernet. (authors)

  4. Glucinium dosimetry in beryl

    International Nuclear Information System (INIS)

    Kremer, M.

    1949-05-01

    The application of the method developed by Kolthoff and Sandell (1928) for the dosimetry of glucinium (beryllium) in beryl gives non-reproducible results with up to 20% discrepancies. This method recommends to separate beryllium and aluminium using 8 hydroxyquinoline and then to directly precipitate glucinium in the filtrate using ammonia. One possible reason of the problems generated by this method should be the formation of a volatile complex between beryllium and the oxine. This work shows that when the oxine is eliminated before the precipitation with ammonia the dosimetry of beryllium becomes accurate. The destruction of the oxine requires the dry evaporation of the filtrate, which is a long process. Thus the search for a reagent allowing the quantitative precipitation of beryllium in its solutions and in presence of oxine has been made. It has been verified also that the quantitative precipitation of the double beryllium and ammonium phosphate is not disturbed by the oxine in acetic buffer. This method, which gives good results, has also the advantage to separate beryllium from the alkaline-earth compounds still present in the filtrate. The report details the operation mode of the method: beryllium dosimetry using ammonium phosphate, aluminium-beryllium separation, application to beryl dosimetry (ore processing, insolubilization of silica, precipitation with ammonia, precipitation with oxine, precipitation of PO 4 NH 4 Gl, preciseness). (J.S.)

  5. Experimental determination of beam quality conversion factors kQ in clinical photon beams using ferrous sulphate (Fricke) dosimetry

    International Nuclear Information System (INIS)

    Palm, A.; Mattsson, Olof

    2002-01-01

    The implementation of protocols based on absorbed dose to water standards requires beam quality conversion factors, k Q . Calculated values of k Q are available for ionization chambers used for reference dosimetry. Ideally, k Q should be experimentally determined at the same beam qualities as that of the user. In this work we measure k Q factors in clinical photon beams and compare them with calculated and measured values. Beam quality conversion factors are determined for clinical photon beams of nominal energies 4 MV, 6 MV, 15 MV, and 25 MV, for commonly used cylindrical ionization chambers. Twelve chambers of eight different types are used. For three of them, no experimental data have previously been available. The experimental procedure is based on measurements with ionization chambers and Fricke dosimetry in the reference beam ( 60 Co γ radiation) and in clinical linear accelerator beams. The k Q values determined in this work generally agree within 0.5% with previously reported experimental values both when %dd(10) x and TPR 20,10 are used for beam quality specification. The agreement with calculated data is generally within 0.5%, except for the 15 MV beam. For this beam the measured values are usually between 0.5% and 1% lower than the data taken from the TG-51 protocol or the TRS-398 code of practice. For three NE2571 chambers and three NE2581 chambers, the maximum observed deviation of individual k Q values is 0.2% and 0.4%, respectively

  6. Proceedings of the 5. symposium on neutron dosimetry. Beam dosimetry

    International Nuclear Information System (INIS)

    Schraube, H.; Burger, G.; Booz, J.

    1985-01-01

    Proceedings of the fifth symposium on neutron dosimetry, organized at Neuherberg, 17-21 September 1984, by the Commission of the European Communities and the GSF Neuherberg, with the co-sponsorship of the US Department of Energy, Office of Health and Environmental Research. The proceedings deal with research on concepts, instruments and methods in radiological protection for neutrons and mixed neutron-gamma fields, including the generation, collection and evaluation of new dosimetric data, the derivation of relevant radiation protection quantitites, and the harmonization of experimental methods and instrumentation by intercomparison programmes. Besides radiation protection monitoring, the proceedings also report on the improvement of neutron beam dosimetry in the fields of radiobiology and radiation therapy

  7. Standardized physics-dosimetry for US pressure vessel cavity surveillance programs

    International Nuclear Information System (INIS)

    Ruddy, F.H.; McElroy, W.N.; Lippincott, E.P.

    1984-01-01

    This paper summarizes the applications of ASTM standard methods, guides and practices to define the selection and deployment of recommended dosimetry sets, the selection of dosimetry capsules and thermal neutron shields, the placement of dosimetry, the methods of measurement of dosimetry sensor reaction products, data analysis procedures, and uncertainty evaluation procedures. It also describes the validation of these standards both by in-reactor testing of advanced PV cavity surveillance physics-dosimetry and by data development. The use of these standards to guide selection and development of advanced dosimetry sets for commercial reactors is also summarized. (Auth.)

  8. New laser technique revives old ideas for thermoluminescence neutron dosimetry

    International Nuclear Information System (INIS)

    Braeunlich, P.; Brown, M.; Gasiot, J.; Fillard, J.P.

    1982-01-01

    Laser heating is discussed as a means to evaluate thermoluminescence dosimeters in neutron dosimetry. Direct energy coupling from the photon beam to the phonons of the TL material permits heating of thin layers with rates of temperature increase exceeding 10 4 Ks - 1 . Rapid TLD evaluation will allow the design of dosimetry badges containing a number of different small thin film TLD elements in various orientations and behind appropriate filters, hydrogenous radiators, etc. Desired redundance is readily possible by using back-up TLDs for every specific task. Reading occurs with a scanning laser beam rather than by mechanically manipulating the TLD toward a fixed heat source. Improvements in the signal-to-noise ratio of up to a factor of 1000 are readily obtained. Thus, sensitive thin-film TLDs can be designed with negligible self-shielding for thermal neutrons in albedo applications and with known, nearly energy dependent cavity correction factors for dosimetry in mixed n-#betta# fields. Due to the greatly increased sensitivity possible with fast laser heating, significant advances are expected in the fast neutron dosimetry techniques which are based on hydrogeneous proton radiators or LET-dependent slow peak formation

  9. Special workshop on lung dosimetry

    International Nuclear Information System (INIS)

    Fisher, D.R.

    1983-01-01

    A Special Workshop on Lung Dosimetry was convened in Salt Lake City, Utah, on April 21-22, 1982, to stimulate the use of improved radiation dosimetry and to formulate a stronger basis for dose-response relationships for inhaled radionuclides. The two-day workshop was held in conjunction with the 30th Annual Meeting of the Radiation Research Society. Publication is planned

  10. Uncertainties associated with the use of optically stimulated luminescence in personal dosimetry

    International Nuclear Information System (INIS)

    Benevides, L.; Romanyukha, A.; Hull, F.; Duffy, M.; Voss, S.; Moscovitch, M.

    2011-01-01

    This study investigates several sources of uncertainty associated with the application of optically stimulated luminescence (OSL) to personal dosimetry. A commercial OSL system based on Al 2 O 3 :C was used for this study. First, it is demonstrated that the concept of repeated evaluation (readout) of the same dosemeter, often referred to as 're-analysis', can introduce uncertainty in the re-estimated dose. This uncertainty is associated with the fact that the re-analysis process depletes some of the populated traps, resulting in a continuous decrease of the OSL signal with each repeated reading. Furthermore, the rate of depletion may be dose-dependent. Second, it is shown that the previously reported light-induced fading in this system is the result of light leaks through miniature openings in the dosemeter badge. (authors)

  11. Dose Estimation from Daily and Weekly Dosimetry Data

    International Nuclear Information System (INIS)

    Ostrouchov, G.

    2001-01-01

    Statistical analyses of data from epidemiologic studies of workers exposed to radiation have been based on recorded annual radiation doses (yearly dose of record). It is usually assumed that the dose values are known exactly, although it is generally recognized that the data contain uncertainty due to measurement error and bias. In our previous work with weekly data, a probability distribution was used to describe an individual's dose during a specific period of time and statistical methods were developed for estimating it from weekly film dosimetry data. This study showed that the yearly dose of record systematically underestimates doses for Oak Ridge National Laboratory (ORNL) workers. This could result in biased estimates of dose-response coefficients and their standard errors. The results of this evaluation raise serious questions about the suitability of the yearly dose of record for direct use in low-dose studies of nuclear industry workers. Here, we extend our previous work to use full information in Pocket meter data and develop the Data Synthesis for Individual Dose Estimation (DSIDE) methodology. Although the DSIDE methodology in this study is developed in the context of daily and weekly data to produce a cumulative yearly dose estimate, in principle it is completely general and can be extended to other time period and measurement combinations. The new methodology takes into account the ''measurement error'' that is produced by the film and pocket-meter dosimetry systems, the biases introduced by policies that lead to recording left-censored doses as zeros, and other measurement and recording practices. The DSIDE method is applied to a sample of dose histories obtained from hard copy dosimetry records at ORNL for the years 1945 to 1955. First, the rigorous addition of daily pocket-meter information shows that the negative bias is generally more severe than was reported in our work based on weekly film data only, however, the amount of bias also varies

  12. Dose Estimation from Daily and Weekly Dosimetry Data

    Energy Technology Data Exchange (ETDEWEB)

    Ostrouchov, G.

    2001-11-16

    Statistical analyses of data from epidemiologic studies of workers exposed to radiation have been based on recorded annual radiation doses (yearly dose of record). It is usually assumed that the dose values are known exactly, although it is generally recognized that the data contain uncertainty due to measurement error and bias. In our previous work with weekly data, a probability distribution was used to describe an individual's dose during a specific period of time and statistical methods were developed for estimating it from weekly film dosimetry data. This study showed that the yearly dose of record systematically underestimates doses for Oak Ridge National Laboratory (ORNL) workers. This could result in biased estimates of dose-response coefficients and their standard errors. The results of this evaluation raise serious questions about the suitability of the yearly dose of record for direct use in low-dose studies of nuclear industry workers. Here, we extend our previous work to use full information in Pocket meter data and develop the Data Synthesis for Individual Dose Estimation (DSIDE) methodology. Although the DSIDE methodology in this study is developed in the context of daily and weekly data to produce a cumulative yearly dose estimate, in principle it is completely general and can be extended to other time period and measurement combinations. The new methodology takes into account the ''measurement error'' that is produced by the film and pocket-meter dosimetry systems, the biases introduced by policies that lead to recording left-censored doses as zeros, and other measurement and recording practices. The DSIDE method is applied to a sample of dose histories obtained from hard copy dosimetry records at ORNL for the years 1945 to 1955. First, the rigorous addition of daily pocket-meter information shows that the negative bias is generally more severe than was reported in our work based on weekly film data only, however, the

  13. Dosimetry of internal emitters

    International Nuclear Information System (INIS)

    Anon.

    1982-01-01

    The Dosimetry of Internal Emitter Program endeavors to refine the correlation between radiation dose and observed biological effects. The program is presently engaged in the development of studies that will demonstrate the applicability of microdosimetry models developed under the Microdosimetry of Internal Sources Program. The program also provides guidance and assistance to Pacific Northwest Laboratory's Biology Department in the dosimetric analysis of internally deposited radionuclides. This report deals with alpha particle dosimetry plutonium 239 inhalation, and in vitro studies of chromosomal observations

  14. Nuclear medicine radiation dosimetry

    CERN Document Server

    McParland, Brian J

    2010-01-01

    Complexities of the requirements for accurate radiation dosimetry evaluation in both diagnostic and therapeutic nuclear medicine (including PET) have grown over the past decade. This is due primarily to four factors: growing consideration of accurate patient-specific treatment planning for radionuclide therapy as a means of improving the therapeutic benefit, development of more realistic anthropomorphic phantoms and their use in estimating radiation transport and dosimetry in patients, design and use of advanced Monte Carlo algorithms in calculating the above-mentioned radiation transport and

  15. Information from the Dosimetry Service

    CERN Multimedia

    2006-01-01

    Please note the following opening hours of the Service: In June: Every morning from 8:30 to 12:00 In July: Mondays, Wednesdays and Fridays from 8:30 to 11:30 Closed all day on Tuesdays and Thursdays From 31st July onwards: Every morning from 8:30 to 12:00 The Service is closed in the afternoons. We should like to remind you that dosimeters cannot be sent to customers by internal mail. Short-term dosimeters (VCTs) must always be returned to the Service after use and must not be left on the racks in the experimental areas or in the secretariats. Dosimetry Service Tel 72155 Bldg. 24 E 011 Dosimetry.service@cern.ch http://cern.ch/rp-dosimetry

  16. WE-AB-204-11: Development of a Nuclear Medicine Dosimetry Module for the GPU-Based Monte Carlo Code ARCHER

    Energy Technology Data Exchange (ETDEWEB)

    Liu, T; Lin, H; Xu, X [Rensselaer Polytechnic Institute, Troy, NY (United States); Stabin, M [Vanderbilt Univ Medical Ctr, Nashville, TN (United States)

    2015-06-15

    Purpose: To develop a nuclear medicine dosimetry module for the GPU-based Monte Carlo code ARCHER. Methods: We have developed a nuclear medicine dosimetry module for the fast Monte Carlo code ARCHER. The coupled electron-photon Monte Carlo transport kernel included in ARCHER is built upon the Dose Planning Method code (DPM). The developed module manages the radioactive decay simulation by consecutively tracking several types of radiation on a per disintegration basis using the statistical sampling method. Optimization techniques such as persistent threads and prefetching are studied and implemented. The developed module is verified against the VIDA code, which is based on Geant4 toolkit and has previously been verified against OLINDA/EXM. A voxelized geometry is used in the preliminary test: a sphere made of ICRP soft tissue is surrounded by a box filled with water. Uniform activity distribution of I-131 is assumed in the sphere. Results: The self-absorption dose factors (mGy/MBqs) of the sphere with varying diameters are calculated by ARCHER and VIDA respectively. ARCHER’s result is in agreement with VIDA’s that are obtained from a previous publication. VIDA takes hours of CPU time to finish the computation, while it takes ARCHER 4.31 seconds for the 12.4-cm uniform activity sphere case. For a fairer CPU-GPU comparison, more effort will be made to eliminate the algorithmic differences. Conclusion: The coupled electron-photon Monte Carlo code ARCHER has been extended to radioactive decay simulation for nuclear medicine dosimetry. The developed code exhibits good performance in our preliminary test. The GPU-based Monte Carlo code is developed with grant support from the National Institute of Biomedical Imaging and Bioengineering through an R01 grant (R01EB015478)

  17. INDIVIDUAL DOSIMETRY SERVICE

    CERN Multimedia

    2000-01-01

    Personnel in the distribution groups Aleph, Delphi, L3, Opal who also work for other experiments than at LEP, should contact their dispatchers to explain their activities for the future, after LEP dismantling in order to be maintained on the regular distribution list at Individual DosimetryWe inform all staff and users under regular dosimetric control that the dosimeters for the monitoring period MAY/JUNE will be available from their usual dispatchers on Tuesday 2 May.Please have your films changed before the 12 May.The colour of the dosimeter valid in is MAY/JUNE is YELLOW.Individual Dosimetry Service will be closed on Friday 28 April.

  18. Individualized adjustments to reference phantom internal organ dosimetry—scaling factors given knowledge of patient internal anatomy

    Science.gov (United States)

    Wayson, Michael B.; Bolch, Wesley E.

    2018-04-01

    Various computational tools are currently available that facilitate patient organ dosimetry in diagnostic nuclear medicine, yet they are typically restricted to reporting organ doses to ICRP-defined reference phantoms. The present study, while remaining computational phantom based, provides straightforward tools to adjust reference phantom organ dose for both internal photon and electron sources. A wide variety of monoenergetic specific absorbed fractions were computed using radiation transport simulations for tissue spheres of varying size and separation distance. Scaling methods were then constructed for both photon and electron self-dose and cross-dose, with data validation provided from patient-specific voxel phantom simulations, as well as via comparison to the scaling methodology given in MIRD Pamphlet No. 11. Photon and electron self-dose was found to be dependent on both radiation energy and sphere size. Photon cross-dose was found to be mostly independent of sphere size. Electron cross-dose was found to be dependent on sphere size when the spheres were in close proximity, owing to differences in electron range. The validation studies showed that this dataset was more effective than the MIRD 11 method at predicting patient-specific photon doses for at both high and low energies, but gave similar results at photon energies between 100 keV and 1 MeV. The MIRD 11 method for electron self-dose scaling was accurate for lower energies but began to break down at higher energies. The photon cross-dose scaling methodology developed in this study showed gains in accuracy of up to 9% for actual patient studies, and the electron cross-dose scaling methodology showed gains in accuracy up to 9% as well when only the bremsstrahlung component of the cross-dose was scaled. These dose scaling methods are readily available for incorporation into internal dosimetry software for diagnostic phantom-based organ dosimetry.

  19. Dosimetry system of the RB reactor

    International Nuclear Information System (INIS)

    Lolic, B.; Vukadin, D.

    1962-01-01

    Although RB reactor is operated at very low power levels, safety and dosimetry systems have high importance. This paper shows detailed dosimetry system with fundamental typical components. Estimated radiation doses dependent on reactor power are given at some characteristic points in the rooms nearby reactor

  20. Pre-clinical evaluation of a diode-based In vivo dosimetry system

    International Nuclear Information System (INIS)

    Trujillo, G.

    1998-01-01

    Diode detector systems are routinely used in a number of departments for the quality assurance of the delivered dose in radiation oncology (1,2,3,4,5). The main advantage of diode detectors for in vivo dosimetry (over TLDs, film dosimetry, ionization chambers) is that results are immediately available in real time, do not need external bias voltage and are more sensitive for the same detection volume than ionization chambers thereby allowing a direct and immediate check of the treatment accuracy. Also, is important to mention that is possible to obtain different accuracy levels. For example, in the case of the measurements designed for evaluating the dosimetric accuracy of a new treatment technique for dose escalation studies the action level should be tighter (the order of 2 % to 4 %, 2 standard deviations) than for routine measurements aiming to discover and correct for errors in the treatment of individual patients (± 5 % - 10 % or to avoid mis administrations (10 % - 15 %). This work describes the calibration method adopted and the evaluation of the accuracy and precision of in vivo dosimetry at Co 60 and 23 MV photon energies. Extensive phantoms measurements were made to determine the influence of physical conditions on the diode response. Parameters investigated included diode linearity, leakage, and measurement reproducibility, as well as the field size, SSD, and angular dependence. the practical consequences of these measurements are reported. There is still some controversy as to whether in vivo (diode) dosemeters are required for routine quality assurance purposes. Our work has shown that while care must be taken in choosing and handling diode detector systems they are able to provide an efficient and effective method of ensuring the dose delivered to the patient during treatment is within acceptable limits. (Author)