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Sample records for internal dose coefficient

  1. Problems is applying new internal dose coefficients to radiation control

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Yuichi [Oarai Laboratory, Chiyoda Technol Corporation, Ibaraki (Japan)

    1998-06-01

    The author discussed problems concerning the conceivable influence in the radiation control and those newly developing when the new internal dose coefficients are applied in the law in the future. For the conceivable influence, the occupational and public exposure was discussed: In the former, the effective dose equivalent limit (at present, 50 mSv/y) was thought to be reduced and in the latter, the limit to be obscure although it might be more greatly influenced by the new coefficients. For newly developing problems, since the new biological model which is more realistic was introduced for calculation of the internal dose and made the calculation more complicated, use of computer is requisite. The effective dose of the internal exposure in the individual monitoring should be conveniently calculated as done at present even after application of the new coefficients. For calculation of the effective dose of the internal exposure, there are such problems as correction of the inhaled particle size and of the individual personal parameter. A model calculation of residual rate in the chest where the respiratory tract alone participated was presented as an example but for the whole body, more complicated functions were pointed out necessary. The concept was concluded to be incorporated in the law in a convenient and easy manner and a software for calculation of internal dose using the new coefficients was wanted. (K.H.)

  2. Internal Dose Conversion Coefficients of Domestic Reference Animal and Plants for Dose Assessment of Non-human Species

    International Nuclear Information System (INIS)

    Keum, Dong Kwon; Jun, In; Lim, Kwang Muk; Choi, Yong Ho

    2009-01-01

    Traditionally, radiation protection has been focused on a radiation exposure of human beings. In the international radiation protection community, one of the recent key issues is to establish the methodology for assessing the radiological impact of an ionizing radiation on non-human species for an environmental protection. To assess the radiological impact to non-human species dose conversion coefficients are essential. This paper describes the methodology to calculate the internal dose conversion coefficient for non-human species and presents calculated internal dose conversion coefficients of 25 radionuclides for 8 domestic reference animal and plants

  3. Absorbed Internal Dose Conversion Coefficients for Domestic Reference Animals and Plant

    Energy Technology Data Exchange (ETDEWEB)

    Keum, Dong Kwon; Jun, In; Lim, Kwang Muk; Choi, Yong Ho [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2010-02-15

    This paper describes the methodology of calculating the internal dose conversion coefficient in order to assess the radiological impact on non-human species. This paper also presents the internal dose conversion coefficients of 25 radionuclides ({sup 3}H, {sup 7}Be, {sup 14}C, {sup 40}K, {sup 51}Cr, {sup 54}Mn, {sup 59}Fe, {sup 58}Co, {sup 60}Co, {sup 65}Zn, {sup 90}Sr, '9{sup 5}Zr, {sup 95}Nb, {sup 99}Tc, {sup 106}Ru, {sup 129}I, {sup 131}I, {sup 136}Cs, {sup 137}Cs, {sup 140}Ba, {sup 140}La, {sup 144}Ce, {sup 238}U, {sup 239}Pu, {sup 240}Pu) for domestic seven reference animals (roe deer, rat, frog, snake, Chinese minnow, bee, and earthworm) and one reference plant (pine tree). The uniform isotropic model was applied in order to calculate the internal dose conversion coefficients. The calculated internal dose conversion coefficient (muGyd{sup -1} per Bqkg{sup -1}) ranged from 10{sup -6} to 10{sup -2} according to the type of radionuclides and organisms studied. It turns out that the internal does conversion coefficient was higher for alpha radionuclides, such as {sup 238}U, {sup 239}Pu, and {sup 240}Pu, and for large organisms, such as roe deer and pine tree. The internal dose conversion coefficients of {sup 239}Pu, {sup 240}Pu, {sup 238}U, {sup 14}C, {sup 3}H and {sup 99}Tc were independent of the organism

  4. Recent developments in biokinetic models and the calculation of internal dose coefficients

    International Nuclear Information System (INIS)

    Fell, T.P.; Phipps, A.W.; Kendall, G.M.; Stradling, G.N.

    1997-01-01

    In most cases the measurement of radioactivity in an environmental or biological sample will be followed by some estimation of dose and possibly risk, either to a population or an individual. This will normally involve the use of a dose coefficient (dose per unit intake value) taken from a compendium. In recent years the calculation of dose coefficients has seen many developments in both biokinetic modelling and computational capabilities. ICRP has recommended new models for the respiratory tract and for the systemic behavior of many of the more important elements. As well as this, a general age-dependent calculation method has been developed which involves an effectively continuous variation of both biokinetic and dosimetric parameters, facilitating more realistic estimation of doses to young people. These new developments were used in work for recent ICRP, IAEA and CEC compendia of dose coefficients for both members of the public (including children) and workers. This paper presents a general overview of the method of calculation of internal doses with particular reference to the actinides. Some of the implications for dose coefficients of the new models are discussed. For example it is shown that compared with data in ICRP Publications 30 and 54: the new respiratory tract model generally predicts lower deposition in systemic tissues per unit intake; the new biokinetic models for actinides allow for burial of material deposited on bone surfaces; age-dependent models generally feature faster turnover of material in young people. All of these factors can lead to substantially different estimates of dose and examples of the new dose coefficients are given to illustrate these differences. During the development of the new models for actinides, human bioassay data were used to validate the model. Thus, one would expect the new models to give reasonable predictions of bioassay quantities. Some examples of the bioassay applications, e.g., excretion data for the

  5. Internal dosimetry contamination: update of revision of the dose coefficients for intakes of radionuclides by workers

    International Nuclear Information System (INIS)

    Gomez Parada, I.; Rojo, A.M.; Sanguineti, R.

    1995-01-01

    ICRP publication 60 introduces new biological information related to the detriment associated with radiation exposures. The International Commission on Radiological Protection has also issued, in publications 57, 67 y 69, new biokinetic models for selected radionuclides since the issue of publication 30. In publication 66 the new human respiratory tract model for radiological protection is described. The aim of the present paper is to compare values of dose coefficients for workers calculated using the new tissue weighting factors, biokinetic models and lung model with those given in publication 30.The software package LUPED 1.1 was used to calculate dose coefficients for inhalation and ingestion. When possible, some changes in the biokinetic models were made trying to incorporate new parameters. The following radionuclides were analysed: 60 Co, 90 Sr, 99m Tc, 131 I, 137 Cs, 239 Pu y 241 Am. Most of the inhalation dose coefficients calculated with the new assumptions are within a factor of three of those calculated using the ICRP 30 lung and biokinetic models. Generally, the inhalation dose coefficients calculated with the new respiratory tract model and assuming a 5μm AMAD are lower than those calculated using the ICRP 30 model and parameters. The inhalation dose coefficients are generally within 10-90 % of the corresponding Publication 61 values, the difference tending to increase for relative insoluble compounds. (author). 10 refs., 4 tabs

  6. Internal and external dose conversion coefficient for domestic reference animals and plant

    Energy Technology Data Exchange (ETDEWEB)

    Keum, Dong Kwon; Jun, In; Lim, Kwang Muk; Park, Du Won; Choi, Young Ho

    2009-07-15

    This report presents the internal and external dose conversion coefficients for domestic reference animals and plant, which are essential to assess the radiological impact of an environmental radiation on non-human species. To calculate the dose conversion coefficients, a uniform isotropic model and a Monte Carlo method for a photon transport simulation in environmental media with different densities have been applied for aquatic and terrestrial animals, respectively. In the modeling all the target animals are defined as a simple 3D elliptical shape. To specify the external radiation source it is assumed that aquatic animals are fully immersed in infinite and uniformly contaminated water, and the on-soil animals are living on the surface of a horizontally infinite soil source, and the in-soil organisms are living at the center of a horizontally infinite and uniformly contaminated soil to a depth of 50cm. A set of internal and external dose conversion coefficients for 8 Korean reference animals and plant (rat, roe-deer, frog, snake, Chinese minnow, bee, earthworm, and pine tree) are presented for 25 radionuclides ({sup 3}H, {sup 7}Be, {sup 14}C, {sup 40}K, {sup 51}Cr, {sup 54}Mn, {sup 59}Fe, {sup 58}Co, {sup 60}Co, {sup 65}Zn, {sup 90}Sr, {sup 95}Zr, {sup 95}Nb, {sup 99}Tc, {sup 106}Ru, {sup 129}I, {sup 131}I, {sup 136}Cs, {sup 137}Cs, {sup 140}Ba, {sup 140}La, {sup 144}Ce, {sup 238}U, {sup 239}Pu, and {sup 240}Pu)

  7. Analysis of internal conversion coefficients

    International Nuclear Information System (INIS)

    Coursol, N.; Gorozhankin, V.M.; Yakushev, E.A.; Briancon, C.; Vylov, Ts.

    2000-01-01

    An extensive database has been assembled that contains the three most widely used sets of calculated internal conversion coefficients (ICC): [Hager R.S., Seltzer E.C., 1968. Internal conversion tables. K-, L-, M-shell Conversion coefficients for Z=30 to Z=103, Nucl. Data Tables A4, 1-237; Band I.M., Trzhaskovskaya M.B., 1978. Tables of gamma-ray internal conversion coefficients for the K-, L- and M-shells, 10≤Z≤104, Special Report of Leningrad Nuclear Physics Institute; Roesel F., Fries H.M., Alder K., Pauli H.C., 1978. Internal conversion coefficients for all atomic shells, At. Data Nucl. Data Tables 21, 91-289] and also includes new Dirac-Fock calculations [Band I.M. and Trzhaskovskaya M.B., 1993. Internal conversion coefficients for low-energy nuclear transitions, At. Data Nucl. Data Tables 55, 43-61]. This database is linked to a computer program to plot ICCs and their combinations (sums and ratios) as a function of Z and energy, as well as relative deviations of ICC or their combinations for any pair of tabulated data. Examples of these analyses are presented for the K-shell and total ICCs of the gamma-ray standards [Hansen H.H., 1985. Evaluation of K-shell and total internal conversion coefficients for some selected nuclear transitions, Eur. Appl. Res. Rept. Nucl. Sci. Tech. 11.6 (4) 777-816] and for the K-shell and total ICCs of high multipolarity transitions (total, K-, L-, M-shells of E3 and M3 and K-shell of M4). Experimental data sets are also compared with the theoretical values of these specific calculations

  8. Age-dependent dose coefficients for tritium in Asian populations

    International Nuclear Information System (INIS)

    Trivedi, A.

    1999-10-01

    The International Commission on Radiological Protection (ICRP) Publications 56 (1989) and 67 (1993) have prescribed the biokinetic models and age-dependent dose coefficients for tritiated water and organically bound tritium. The dose coefficients are computed from values selected to specify the anatomical, morphological and physiological characteristics of a three-month-old, one-year-old, five-year-old, 10-year-old, 15-year-old and adult (Reference Man) Caucasian living in North America and Western Europe. However, values for Reference Man and other age groups are not directly applicable to Asians, because of differences in race, custom, dietary habits and climatic conditions. An Asian Man model, including five age groups, has been proposed by Tanaka and Kawamura (1996, 1998) for use in internal dosimetry. The basic concept of the ICRP Reference Man and the system describing body composition in ICRP Publication 23 (1975) were used. Reference values for Asians were given for the body weight and height, the mass of soft tissue, the mass of body water and the daily fluid balance, and are used to compute the dose coefficients for tritium. The age-dependent dose coefficients for Asians for tritiated water intakes are smaller by 20 to 30% of the currently prescribed values (Trivedi, 1998). The reduction in the dose coefficient values is caused by the increased daily fluid balance among Asians. The dose coefficient for tritiated water is 1.4 x 10 -11 Sv Bq -1 for Asian Man compared to 2.0 x 10 -11 Sv Bq -1 for Reference Man. The dose coefficients for organically bound tritium are only marginally different from those of the ICRP values. The dose coefficient for organically bound tritium for Asian Man is 4.0 x 10 -11 Sv Bq -11 compared to 4.6 x 10 -11 Sv Bq -1 for Reference Man. (author)

  9. Age-dependent dose coefficients for tritium in Asian populations

    Energy Technology Data Exchange (ETDEWEB)

    Trivedi, A

    1999-10-01

    The International Commission on Radiological Protection (ICRP) Publications 56 (1989) and 67 (1993) have prescribed the biokinetic models and age-dependent dose coefficients for tritiated water and organically bound tritium. The dose coefficients are computed from values selected to specify the anatomical, morphological and physiological characteristics of a three-month-old, one-year-old, five-year-old, 10-year-old, 15-year-old and adult (Reference Man) Caucasian living in North America and Western Europe. However, values for Reference Man and other age groups are not directly applicable to Asians, because of differences in race, custom, dietary habits and climatic conditions. An Asian Man model, including five age groups, has been proposed by Tanaka and Kawamura (1996, 1998) for use in internal dosimetry. The basic concept of the ICRP Reference Man and the system describing body composition in ICRP Publication 23 (1975) were used. Reference values for Asians were given for the body weight and height, the mass of soft tissue, the mass of body water and the daily fluid balance, and are used to compute the dose coefficients for tritium. The age-dependent dose coefficients for Asians for tritiated water intakes are smaller by 20 to 30% of the currently prescribed values (Trivedi, 1998). The reduction in the dose coefficient values is caused by the increased daily fluid balance among Asians. The dose coefficient for tritiated water is 1.4 x 10{sup -11} Sv Bq{sup -1} for Asian Man compared to 2.0 x 10{sup -11} Sv Bq{sup -1} for Reference Man. The dose coefficients for organically bound tritium are only marginally different from those of the ICRP values. The dose coefficient for organically bound tritium for Asian Man is 4.0 x 10{sup -11} Sv Bq{sup -11} compared to 4.6 x 10{sup -11} Sv Bq{sup -1} for Reference Man. (author)

  10. Dependence of sputtering coefficient on ion dose

    International Nuclear Information System (INIS)

    Colligon, J.S.; Patel, M.H.

    1977-01-01

    The sputtering coefficient of polycrystalline gold bombarded by 10-40 keV Ar + ions had been measured as a function of total ion dose and shown to exhibit oscillations in magnitude between 30 and 100%. Possible experimental errors which would give rise to such an oscillation have been considered, but it is apparent that these factors are unable to explain the measurements. It is proposed that a change in the Sublimation Energy associated with either bulk damage or formation of surface topographical features arising during ion bombardment may be responsible for the observed variations in sputtering coefficient. (author)

  11. Internal dose estimates

    International Nuclear Information System (INIS)

    Wrenn, M.E.

    1977-01-01

    Internal doses, the procedures for making them and their significance has been reviewed. Effects of uranium, radium, lead-210, polonium-210, thorium in man are analysed based on data from tables and plots. Dosimetry of some ingested nuclides and inhalation dose due to radon-222, radon-220 and their daugther products are discussed [pt

  12. Assessment of internal doses

    CERN Document Server

    Rahola, T; Falk, R; Isaksson, M; Skuterud, L

    2002-01-01

    There is a definite need for training in dose calculation. Our first course was successful and was followed by a second, both courses were fully booked. An example of new tools for software products for bioassay analysis and internal dose assessment is the Integrated Modules for Bioassay Analysis (IMBA) were demonstrated at the second course. This suite of quality assured code modules have been adopted in the UK as the standard for regulatory assessment purposes. The intercomparison measurements are an important part of the Quality Assurance work. In what is known as the sup O utside workers ' directive it is stated that the internal dose measurements shall be included in the European Unions supervision system for radiation protection. The emergency preparedness regarding internal contamination was much improved by the training with and calibration of handheld instruments from participants' laboratories. More improvement will be gained with the handbook giving practical instructions on what to do in case of e...

  13. The system of radiation dose assessment and dose conversion coefficients in the ICRP and FGR

    Energy Technology Data Exchange (ETDEWEB)

    Kim, So Ra; Min, Byung Il; Park, Kihyun; Yang, Byung Mo; Suh, Kyung Suk [Nuclear Environmental Safety Research Division, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-12-15

    The International Commission on Radiological Protection (ICRP) recommendations and the Federal Guidance Report (FGR) published by the U.S. Environmental Protection Agency (EPA) have been widely applied worldwide in the fields of radiation protection and dose assessment. The dose conversion coefficients of the ICRP and FGR are widely used for assessing exposure doses. However, before the coefficients are used, the user must thoroughly understand the derivation process of the coefficients to ensure that they are used appropriately in the evaluation. The ICRP provides recommendations to regulatory and advisory agencies, mainly in the form of guidance on the fundamental principles on which appropriate radiological protection can be based. The FGR provides federal and state agencies with technical information to assist their implementation of radiation protection programs for the U.S. population. The system of radiation dose assessment and dose conversion coefficients in the ICRP and FGR is reviewed in this study. A thorough understanding of their background is essential for the proper use of dose conversion coefficients. The FGR dose assessment system was strongly influenced by the ICRP and the U.S. National Council on Radiation Protection and Measurements (NCRP), and is hence consistent with those recommendations. Moreover, the ICRP and FGR both used the scientific data reported by Biological Effects of Ionizing Radiation (BEIR) and United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) as their primary source of information. The difference between the ICRP and FGR lies in the fact that the ICRP utilized information regarding a population of diverse races, whereas the FGR utilized data on the American population, as its goal was to provide guidelines for radiological protection in the US. The contents of this study are expected to be utilized as basic research material in the areas of radiation protection and dose assessment.

  14. The system of radiation dose assessment and dose conversion coefficients in the ICRP and FGR

    International Nuclear Information System (INIS)

    Kim, So Ra; Min, Byung Il; Park, Kihyun; Yang, Byung Mo; Suh, Kyung Suk

    2016-01-01

    The International Commission on Radiological Protection (ICRP) recommendations and the Federal Guidance Report (FGR) published by the U.S. Environmental Protection Agency (EPA) have been widely applied worldwide in the fields of radiation protection and dose assessment. The dose conversion coefficients of the ICRP and FGR are widely used for assessing exposure doses. However, before the coefficients are used, the user must thoroughly understand the derivation process of the coefficients to ensure that they are used appropriately in the evaluation. The ICRP provides recommendations to regulatory and advisory agencies, mainly in the form of guidance on the fundamental principles on which appropriate radiological protection can be based. The FGR provides federal and state agencies with technical information to assist their implementation of radiation protection programs for the U.S. population. The system of radiation dose assessment and dose conversion coefficients in the ICRP and FGR is reviewed in this study. A thorough understanding of their background is essential for the proper use of dose conversion coefficients. The FGR dose assessment system was strongly influenced by the ICRP and the U.S. National Council on Radiation Protection and Measurements (NCRP), and is hence consistent with those recommendations. Moreover, the ICRP and FGR both used the scientific data reported by Biological Effects of Ionizing Radiation (BEIR) and United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) as their primary source of information. The difference between the ICRP and FGR lies in the fact that the ICRP utilized information regarding a population of diverse races, whereas the FGR utilized data on the American population, as its goal was to provide guidelines for radiological protection in the US. The contents of this study are expected to be utilized as basic research material in the areas of radiation protection and dose assessment

  15. Dose coefficients for individual occupationally exposed

    International Nuclear Information System (INIS)

    2005-11-01

    This Regulation refers to the requirements of the Regulation CNEN-NN.3.01, 'Basic Act of Radiological Protection', aiming its application to the dose calculation, with purposes of conformity verification with limits and restrictions of doses and level of reference for individual occupationally exposed, according to the express in its section 5

  16. Determination and reliability of dose coefficients for radiopharmaceuticals; Ermittlung der Zuverlaessigkeit von Dosiskoeffizienten fuer Radiopharmaka

    Energy Technology Data Exchange (ETDEWEB)

    Spielmann, V.; Li, W.B.; Zankl, M.; Oeh, U.

    2015-11-15

    The dose coefficients used in nuclear medicine for dose calculations of radiopharmaceuticals are based on recommendations by ICRP (International Commission on radiological protection) and the MIRD (Medical Internal Radiation Dose Committee) using mathematical models for the temporal activity distributions in organs and tissues (biokinetic models) and mathematical models of the human body. These models using an idealized human body do not include uncertainty estimations. The research project is aimed to determine the uncertainties and thus the reliability of the dose coefficients for radiopharmaceuticals and to identify the biokinetic and dosimetric parameters that contribute most of the uncertainties.

  17. Dose conversion coefficients for high-energy photons, electrons, neutrons and protons

    CERN Document Server

    Sakamoto, Y; Sato, O; Tanaka, S I; Tsuda, S; Yamaguchi, Y; Yoshizawa, N

    2003-01-01

    In the International Commission on Radiological Protection (ICRP) 1990 Recommendations, radiation weighting factors were introduced in the place of quality factors, the tissue weighting factors were revised, and effective doses and equivalent doses of each tissues and organs were defined as the protection quantities. Dose conversion coefficients for photons, electrons and neutrons based on new ICRP recommendations were cited in the ICRP Publication 74, but the energy ranges of theses data were limited and there are no data for high energy radiations produced in accelerator facilities. For the purpose of designing the high intensity proton accelerator facilities at JAERI, the dose evaluation code system of high energy radiations based on the HERMES code was developed and the dose conversion coefficients of effective dose were evaluated for photons, neutrons and protons up to 10 GeV, and electrons up to 100 GeV. The dose conversion coefficients of effective dose equivalent were also evaluated using quality fact...

  18. Relationship between attenuation coefficients and dose-spread kernels

    International Nuclear Information System (INIS)

    Boyer, A.L.

    1988-01-01

    Dose-spread kernels can be used to calculate the dose distribution in a photon beam by convolving the kernel with the primary fluence distribution. The theoretical relationships between various types and components of dose-spread kernels relative to photon attenuation coefficients are explored. These relations can be valuable as checks on the conservation of energy by dose-spread kernels calculated by analytic or Monte Carlo methods

  19. Graphical comparison of calculated internal conversion coefficients

    International Nuclear Information System (INIS)

    Ewbank, W.B.

    1980-11-01

    Calculated values of the coefficients of internal conversion of gamma rays in the K shell and L 1 , L 2 , L 3 subshells from published tabulations by Band and Trzhaskovskaya and by Roesel et al. at Data Nucl. Data Tables, 21, 92-514(1978) are compared with values obtained by computer interpolation among tabulated values of Hager and Seltzer Nucl. Data, A4, 1-235(1968). In some cases, agreement among the three calculations is remarkably good, and differences are generally less than 5%. In a few cases, there are differences as large as 20 to 50%, corresponding to the threshold effect described by Roesel et al. The Z-dependent resonance minimum described by Roesel et al. is also observed in the comparison of E1-E4 conversion in the L 1 subshell. In several cases (notably M1-M4 conversion in the K shell and L 1 subshell), the Band and Roesel calculations show dramatically different dependence on gamma energy and atomic number. For Z = 100, the Band calculation for E4 conversion in the L 3 subshell shows irregular behavior at energies below the K-shell binding energy. A few high-quality measurements of internal conversion coefficients (+-5%) would help greatly to establish a basis for choice among the theoretical calculations. 32 figures

  20. Conversion coefficients for determining organ doses in paediatric spine radiography

    Energy Technology Data Exchange (ETDEWEB)

    Seidenbusch, Michael; Schneider, Karl [Ludwig-Maximilians-University of Munich, Institute of Clinical Radiology - Paediatric Radiology, Muenchen (Germany)

    2014-04-15

    Knowledge of organ and effective doses achieved during paediatric x-ray examinations is an important prerequisite for assessment of radiation burden to the patient. Conversion coefficients for reconstruction of organ and effective doses from entrance doses for segmental spine radiographs of 0-, 1-, 5-, 10-, 15- and 30-year-old patients are provided regarding the Guidelines of Good Radiographic Technique of the European Commission. Using the personal computer program PCXMC developed by the Finnish Centre for Radiation and Nuclear Safety (Saeteilyturvakeskus STUK), conversion coefficients for conventional segmental spine radiographs were calculated performing Monte Carlo simulations in mathematical hermaphrodite phantom models describing patients of different ages. The clinical variation of beam collimation was taken into consideration by defining optimal and suboptimal radiation field settings. Conversion coefficients for the reconstruction of organ doses in about 40 organs and tissues from measured entrance doses during cervical, thoracic and lumbar spine radiographs of 0-, 1-, 5-, 10-, 15- and 30-year-old patients were calculated for the standard sagittal and lateral beam projections and the standard focus detector distance of 115 cm. The conversion coefficients presented may be used for organ dose assessments from entrance doses measured during spine radiographs of patients of all age groups and all field settings within the optimal and suboptimal standard field settings. (orig.)

  1. Local organ dose conversion coefficients for angiographic examinations of coronary arteries

    International Nuclear Information System (INIS)

    Schlattl, H; Zankl, M; Hausleiter, J; Hoeschen, C

    2007-01-01

    New organ dose conversion coefficients for coronary angiographic interventions are presented, as well as dose distributions and resulting maximal local dose conversion coefficients in the relevant organs. For the Monte Carlo based simulations, voxel models of the human anatomy were employed which represent the average Caucasian adult man and woman as defined by the International Commission on Radiological Protection. In the 21 investigated projections, the mean organ dose conversion coefficients vary from a few 0.01 to 2 mGy(Gy cm 2 ) -1 , depending on the projections. However, especially in portions of the lungs and the active bone marrow, the conversion coefficients can locally amount up to 10 mGy(Gy cm 2 ) -1 , which is half the average conversion coefficient of the skin at the field entrance. In addition to the dose conversion coefficients, the dependence of the patient dose on the projection has been estimated. It could be shown that the patient doses are highest for left anterior oblique views with strong caudal or cranial orientation. Nevertheless, for a large range of image-intensifier positions no significant dose differences could be found

  2. Methods for calculating dose conversion coefficients for terrestrial and aquatic biota

    International Nuclear Information System (INIS)

    Ulanovsky, A.; Proehl, G.; Gomez-Ros, J.M.

    2008-01-01

    Plants and animals may be exposed to ionizing radiation from radionuclides in the environment. This paper describes the underlying data and assumptions to assess doses to biota due to internal and external exposure for a wide range of masses and shapes living in various habitats. A dosimetric module is implemented which is a user-friendly and flexible possibility to assess dose conversion coefficients for aquatic and terrestrial biota. The dose conversion coefficients have been derived for internal and various external exposure scenarios. The dosimetric model is linked to radionuclide decay and emission database, compatible with the ICRP Publication 38, thus providing a capability to compute dose conversion coefficients for any nuclide from the database and its daughter nuclides. The dosimetric module has been integrated into the ERICA Tool, but it can also be used as a stand-alone version

  3. Effective dose rate coefficients for exposure to contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Veinot, K.G. [Easterly Scientific, Knoxville, TN (United States); Y-12 National Security Complex, Oak Ridge, TN (United States); Eckerman, K.F.; Easterly, C.E. [Easterly Scientific, Knoxville, TN (United States); Bellamy, M.B.; Hiller, M.M.; Dewji, S.A. [Oak Ridge National Laboratory, Center for Radiation Protection Knowledge, Oak Ridge, TN (United States); Hertel, N.E. [Oak Ridge National Laboratory, Center for Radiation Protection Knowledge, Oak Ridge, TN (United States); Georgia Institute of Technology, Atlanta, GA (United States); Manger, R. [University of California San Diego, Department of Radiation Medicine and Applied Sciences, La Jolla, CA (United States)

    2017-08-15

    The Oak Ridge National Laboratory Center for Radiation Protection Knowledge has undertaken calculations related to various environmental exposure scenarios. A previous paper reported the results for submersion in radioactive air and immersion in water using age-specific mathematical phantoms. This paper presents age-specific effective dose rate coefficients derived using stylized mathematical phantoms for exposure to contaminated soils. Dose rate coefficients for photon, electron, and positrons of discrete energies were calculated and folded with emissions of 1252 radionuclides addressed in ICRP Publication 107 to determine equivalent and effective dose rate coefficients. The MCNP6 radiation transport code was used for organ dose rate calculations for photons and the contribution of electrons to skin dose rate was derived using point-kernels. Bremsstrahlung and annihilation photons of positron emission were evaluated as discrete photons. The coefficients calculated in this work compare favorably to those reported in the US Federal Guidance Report 12 as well as by other authors who employed voxel phantoms for similar exposure scenarios. (orig.)

  4. The computation of ICRP dose coefficients for intakes of radionuclides with PLEIADES: biokinetic aspects.

    Science.gov (United States)

    Fell, T P

    2007-01-01

    The ICRP has published dose coefficients for the ingestion or inhalation of radionuclides in a series of reports covering intakes by workers and members of the public including children and pregnant or lactating women. The calculation of these coefficients conveniently divides into two distinct parts--the biokinetic and dosimetric. This paper gives a brief summary of the methods used to solve the biokinetic problem in the generation of dose coefficients on behalf of the ICRP, as implemented in the Health Protection Agency's internal dosimetry code PLEIADES.

  5. The computation of ICRP dose coefficients for intakes of radionuclides with PLEIADES: biokinetic aspects

    International Nuclear Information System (INIS)

    Fell, T.P.

    2007-01-01

    The ICRP has published dose coefficients for the ingestion or inhalation of radionuclides in a series of reports covering intakes by workers and members of the public including children and pregnant or lactating women. The calculation of these coefficients conveniently divides into two distinct parts - the biokinetic and dosimetric. This paper gives a brief summary of the methods used to solve the biokinetic problem in the generation of dose coefficients on behalf of the ICRP, as implemented in the Health Protection Agency's internal dosimetry code PLEIADES. (author)

  6. Organ and effective dose rate coefficients for submersion exposure in occupational settings

    International Nuclear Information System (INIS)

    Veinot, K.G.; Dewji, S.A.; Hiller, M.M.; Eckerman, K.F.; Easterly, C.E.

    2017-01-01

    External dose coefficients for environmental exposure scenarios are often computed using assumption on infinite or semi-infinite radiation sources. For example, in the case of a person standing on contaminated ground, the source is assumed to be distributed at a given depth (or between various depths) and extending outwards to an essentially infinite distance. In the case of exposure to contaminated air, the person is modeled as standing within a cloud of infinite, or semi-infinite, source distribution. However, these scenarios do not mimic common workplace environments where scatter off walls and ceilings may significantly alter the energy spectrum and dose coefficients. In this paper, dose rate coefficients were calculated using the International Commission on Radiological Protection (ICRP) reference voxel phantoms positioned in rooms of three sizes representing an office, laboratory, and warehouse. For each room size calculations using the reference phantoms were performed for photons, electrons, and positrons as the source particles to derive mono-energetic dose rate coefficients. Since the voxel phantoms lack the resolution to perform dose calculations at the sensitive depth for the skin, a mathematical phantom was developed and calculations were performed in each room size with the three source particle types. Coefficients for the noble gas radionuclides of ICRP Publication 107 (e.g., Ne, Ar, Kr, Xe, and Rn) were generated by folding the corresponding photon, electron, and positron emissions over the mono-energetic dose rate coefficients. Results indicate that the smaller room sizes have a significant impact on the dose rate per unit air concentration compared to the semi-infinite cloud case. For example, for Kr-85 the warehouse dose rate coefficient is 7% higher than the office dose rate coefficient while it is 71% higher for Xe-133. (orig.)

  7. Organ and effective dose rate coefficients for submersion exposure in occupational settings

    Energy Technology Data Exchange (ETDEWEB)

    Veinot, K.G. [Easterly Scientific, Knoxville, TN (United States); Y-12 National Security Complex, Oak Ridge, TN (United States); Dewji, S.A.; Hiller, M.M. [Center for Radiation Protection Knowledge, Oak Ridge National Laboratory, Oak Ridge, TN (United States); Eckerman, K.F.; Easterly, C.E. [Easterly Scientific, Knoxville, TN (United States)

    2017-11-15

    External dose coefficients for environmental exposure scenarios are often computed using assumption on infinite or semi-infinite radiation sources. For example, in the case of a person standing on contaminated ground, the source is assumed to be distributed at a given depth (or between various depths) and extending outwards to an essentially infinite distance. In the case of exposure to contaminated air, the person is modeled as standing within a cloud of infinite, or semi-infinite, source distribution. However, these scenarios do not mimic common workplace environments where scatter off walls and ceilings may significantly alter the energy spectrum and dose coefficients. In this paper, dose rate coefficients were calculated using the International Commission on Radiological Protection (ICRP) reference voxel phantoms positioned in rooms of three sizes representing an office, laboratory, and warehouse. For each room size calculations using the reference phantoms were performed for photons, electrons, and positrons as the source particles to derive mono-energetic dose rate coefficients. Since the voxel phantoms lack the resolution to perform dose calculations at the sensitive depth for the skin, a mathematical phantom was developed and calculations were performed in each room size with the three source particle types. Coefficients for the noble gas radionuclides of ICRP Publication 107 (e.g., Ne, Ar, Kr, Xe, and Rn) were generated by folding the corresponding photon, electron, and positron emissions over the mono-energetic dose rate coefficients. Results indicate that the smaller room sizes have a significant impact on the dose rate per unit air concentration compared to the semi-infinite cloud case. For example, for Kr-85 the warehouse dose rate coefficient is 7% higher than the office dose rate coefficient while it is 71% higher for Xe-133. (orig.)

  8. Age-dependent conversion coefficients for organ doses and effective doses for external neutron irradiation

    International Nuclear Information System (INIS)

    Nishizaki, Chihiro; Endo, Akira; Takahashi, Fumiaki

    2006-06-01

    To utilize dose assessment of the public for external neutron irradiation, conversion coefficients of absorbed doses of organs and effective doses were calculated using the numerical simulation technique for six different ages (adult, 15, 10, 5 and 1 years and newborn), which represent the member of the public. Calculations were performed using six age-specific anthropomorphic phantoms and a Monte Carlo radiation transport code for two irradiation geometries, anterior-posterior and rotational geometries, for 20 incident energies from thermal to 20 MeV. Effective doses defined by the 1990 Recommendation of ICRP were calculated from the absorbed doses in 21 organs. The calculated results were tabulated in the form of absorbed doses and effective doses per unit neutron fluence. The calculated conversion coefficients are used for dose assessment of the public around nuclear facilities and accelerator facilities. (author)

  9. Influence on dose coefficients for workers of the new metabolic models

    International Nuclear Information System (INIS)

    Gomez Parada, I.M.; Rojo, A.M.

    1998-01-01

    The International Commission on Radiological Protection (ICRP) has recently reviewed the biokinetic models used in the internal contamination dose assessment. ICRP has adopted a new model for the human respiratory tract and has updated, in ICRP Publications 56, 67 and 69, some of the biokinetic models of ICRP Publication 30. In this paper, the dose coefficients for some selected radionuclides issued in ICRP Publication 68 are compared with those obtained using the software LUPED (LUng Dose Evaluation Program). The former were calculated using the new systemic models, while the latter are based on the old metabolic models. The aim is to know to what extent the new models for systematic retention influence the dose coefficients for workers. (author) [es

  10. Internal dose assessment in radiation accidents

    International Nuclear Information System (INIS)

    Toohey, R.E.

    2003-01-01

    Although numerous models have been developed for occupational and medical internal dosimetry, they may not be applicable to an accident situation. Published dose coefficients relate effective dose to intake, but if acute deterministic effects are possible, effective dose is not a useful parameter. Consequently, dose rates to the organs of interest need to be computed from first principles. Standard bioassay methods may be used to assess body contents, but, again, the standard models for bioassay interpretation may not be applicable because of the circumstances of the accident and the prompt initiation of decorporation therapy. Examples of modifications to the standard methodologies include adjustment of biological half-times under therapy, such as in the Goiania accident, and the same effect, complicated by continued input from contaminated wounds, in the Hanford 241 Am accident. (author)

  11. Neutron fluence-to-dose conversion coefficients for embryo and fetus

    International Nuclear Information System (INIS)

    Chen, J.; Meyerhof, D.; Vlahovich, S.

    2004-01-01

    A problem of concern in radiation protection is the exposure of pregnant women to ionising radiation, because of the high radiosensitivity of the embryo and fetus. External neutron exposure is of concern when pregnant women travel by aeroplane. Dose assessments for neutrons frequently rely on fluence-to-dose conversion coefficients. While neutron fluence-to-dose conversion coefficients for adults are recommended in International Commission on Radiological Protection publications and International Commission on Radiological Units and Measurements reports, conversion coefficients for embryos and fetuses are not given in the publications. This study undertakes Monte Carlo calculations to determine the mean absorbed doses to the embryo and fetus when the mother is exposed to neutron fields. A new set of mathematical models for the embryo and fetus has been developed at Health Canada and is used together with mathematical phantoms of a pregnant female developed at Oak Ridge National Laboratory. Monoenergetic neutrons from 1 eV to 10 MeV are considered in this study. The irradiation geometries include antero-posterior (AP), postero-anterior (PA), lateral (LAT), rotational (ROT) and isotropic (ISO) geometries. At each of these standard irradiation geometries, absorbed doses to the fetal brain and body are calculated; for the embryo at 8 weeks and the fetus at 3, 6 or 9 months. Neutron fluence-to-absorbed dose conversion coefficients are derived for the four age groups. Neutron fluence-to-equivalent dose conversion coefficients are given for the AP irradiations which yield the highest radiation dose to the fetal body in the neutron energy range considered here. The results indicate that for neutrons <10 MeV more protection should be given to pregnant women in the first trimester due to the higher absorbed dose per unit neutron fluence to the fetus. (authors)

  12. Neutron fluence-to-dose conversion coefficients for embryo and fetus.

    Science.gov (United States)

    Chen, Jing; Meyerhof, Dorothy; Vlahovich, Slavica

    2004-01-01

    A problem of concern in radiation protection is the exposure of pregnant women to ionising radiation, because of the high radiosensitivity of the embryo and fetus. External neutron exposure is of concern when pregnant women travel by aeroplane. Dose assessments for neutrons frequently rely on fluence-to-dose conversion coefficients. While neutron fluence-to-dose conversion coefficients for adults are recommended in International Commission on Radiological Protection publications and International Commission on Radiological Units and Measurements reports, conversion coefficients for embryos and fetuses are not given in the publications. This study undertakes Monte Carlo calculations to determine the mean absorbed doses to the embryo and fetus when the mother is exposed to neutron fields. A new set of mathematical models for the embryo and fetus has been developed at Health Canada and is used together with mathematical phantoms of a pregnant female developed at Oak Ridge National Laboratory. Monoenergetic neutrons from 1 eV to 10 MeV are considered in this study. The irradiation geometries include antero-posterior (AP), postero-anterior (PA), lateral (LAT), rotational (ROT) and isotropic (ISO) geometries. At each of these standard irradiation geometries, absorbed doses to the fetal brain and body are calculated; for the embryo at 8 weeks and the fetus at 3, 6 or 9 months. Neutron fluence-to-absorbed dose conversion coefficients are derived for the four age groups. Neutron fluence-to-equivalent dose conversion coefficients are given for the AP irradiations which yield the highest radiation dose to the fetal body in the neutron energy range considered here. The results indicate that for neutrons <10 MeV more protection should be given to pregnant women in the first trimester due to the higher absorbed dose per unit neutron fluence to the fetus.

  13. Determination of fluence-to-dose conversion coefficients by means of artificial neural networks

    International Nuclear Information System (INIS)

    Soto B, T. G.; Rivera P, E.; De Leon M, H. A.; Hernandez D, V. M.; Vega C, H. R.; Gallego, E.; Lorente, A.

    2012-10-01

    In this paper is presented an Artificial Neural Network (Ann) that has been designed, trained and validated to determinate the effective dose e, ambient dose equivalent h(10) and personal dose equivalent hp(10,θ) fluence-to-dose conversion coefficients at different positions, having as only input data 7 count rates obtained with a Bonner Sphere Spectrometer (Bss) system. A set of 211 neutron spectra and the fluence-to-dose conversion coefficients published by the International Atomic Energy Agency were used to train and validate the Ann. This set was divided into 2 subsets, one of 181 elements to train the Ann and the remaining 30 to validate it. The Ann was trained using Bss count rates as input data and the fluence-to-dose conversion coefficients as output data. The network was validated and tested with the set of 30 elements that were not used during the training process. Good results were obtained proving that Ann are a good choice for calculating the fluence-to-dose conversion coefficients having as only data the count rates obtained with a Bss. (Author)

  14. Determination of fluence-to-dose conversion coefficients by means of artificial neural networks

    Energy Technology Data Exchange (ETDEWEB)

    Soto B, T. G.; Rivera P, E.; De Leon M, H. A.; Hernandez D, V. M.; Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico); Gallego, E.; Lorente, A., E-mail: tzinnia.soto@gmail.com [Universidad Politecnica de Madrid, Departamento de Ingenieria Nuclear, Jose Gutierrez Abascal No. 2, 28006 Madrid (Spain)

    2012-10-15

    In this paper is presented an Artificial Neural Network (Ann) that has been designed, trained and validated to determinate the effective dose e, ambient dose equivalent h(10) and personal dose equivalent hp(10,{theta}) fluence-to-dose conversion coefficients at different positions, having as only input data 7 count rates obtained with a Bonner Sphere Spectrometer (Bss) system. A set of 211 neutron spectra and the fluence-to-dose conversion coefficients published by the International Atomic Energy Agency were used to train and validate the Ann. This set was divided into 2 subsets, one of 181 elements to train the Ann and the remaining 30 to validate it. The Ann was trained using Bss count rates as input data and the fluence-to-dose conversion coefficients as output data. The network was validated and tested with the set of 30 elements that were not used during the training process. Good results were obtained proving that Ann are a good choice for calculating the fluence-to-dose conversion coefficients having as only data the count rates obtained with a Bss. (Author)

  15. Delimiting Coefficient a from Internal Consistency and Unidimensionality

    Science.gov (United States)

    Sijtsma, Klaas

    2015-01-01

    I discuss the contribution by Davenport, Davison, Liou, & Love (2015) in which they relate reliability represented by coefficient a to formal definitions of internal consistency and unidimensionality, both proposed by Cronbach (1951). I argue that coefficient a is a lower bound to reliability and that concepts of internal consistency and…

  16. Personal dose equivalent conversion coefficients for electrons to 1 Ge V.

    Science.gov (United States)

    Veinot, K G; Hertel, N E

    2012-04-01

    In a previous paper, conversion coefficients for the personal dose equivalent, H(p)(d), for photons were reported. This note reports values for electrons calculated using similar techniques. The personal dose equivalent is the quantity used to approximate the protection quantity effective dose when performing personal dosemeter calibrations and in practice the personal dose equivalent is determined using a 30×30×15 cm slab-type phantom. Conversion coefficients to 1 GeV have been calculated for H(p)(10), H(p)(3) and H(p)(0.07) in the recommended slab phantom. Although the conversion coefficients were determined for discrete incident energies, analytical fits of the conversion coefficients over the energy range are provided using a similar formulation as in the photon results previously reported. The conversion coefficients for the personal dose equivalent are compared with the appropriate protection quantity, calculated according to the recommendations of the latest International Commission on Radiological Protection guidance. Effects of eyewear on H(p)(3) are also discussed.

  17. Determination of absolute internal conversion coefficients using the SAGE spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Sorri, J., E-mail: juha.m.t.sorri@jyu.fi [University of Jyvaskyla, Department of Physics, P.O. Box 35, FI-40014 University of Jyvaskyla (Finland); Greenlees, P.T.; Papadakis, P.; Konki, J. [University of Jyvaskyla, Department of Physics, P.O. Box 35, FI-40014 University of Jyvaskyla (Finland); Cox, D.M. [University of Jyvaskyla, Department of Physics, P.O. Box 35, FI-40014 University of Jyvaskyla (Finland); Department of Physics, University of Liverpool, Oxford Street, Liverpool L69 7ZE (United Kingdom); Auranen, K.; Partanen, J.; Sandzelius, M.; Pakarinen, J.; Rahkila, P.; Uusitalo, J. [University of Jyvaskyla, Department of Physics, P.O. Box 35, FI-40014 University of Jyvaskyla (Finland); Herzberg, R.-D. [Department of Physics, University of Liverpool, Oxford Street, Liverpool L69 7ZE (United Kingdom); Smallcombe, J.; Davies, P.J.; Barton, C.J.; Jenkins, D.G. [Department of Physics, University of York, Heslington, York YO10 5DD (United Kingdom)

    2016-03-11

    A non-reference based method to determine internal conversion coefficients using the SAGE spectrometer is carried out for transitions in the nuclei of {sup 154}Sm, {sup 152}Sm and {sup 166}Yb. The Normalised-Peak-to-Gamma method is in general an efficient tool to extract internal conversion coefficients. However, in many cases the required well-known reference transitions are not available. The data analysis steps required to determine absolute internal conversion coefficients with the SAGE spectrometer are presented. In addition, several background suppression methods are introduced and an example of how ancillary detectors can be used to select specific reaction products is given. The results obtained for ground-state band E2 transitions show that the absolute internal conversion coefficients can be extracted using the methods described with a reasonable accuracy. In some cases of less intense transitions only an upper limit for the internal conversion coefficient could be given.

  18. Determination of absolute internal conversion coefficients using the SAGE spectrometer

    International Nuclear Information System (INIS)

    Sorri, J.; Greenlees, P.T.; Papadakis, P.; Konki, J.; Cox, D.M.; Auranen, K.; Partanen, J.; Sandzelius, M.; Pakarinen, J.; Rahkila, P.; Uusitalo, J.; Herzberg, R.-D.; Smallcombe, J.; Davies, P.J.; Barton, C.J.; Jenkins, D.G.

    2016-01-01

    A non-reference based method to determine internal conversion coefficients using the SAGE spectrometer is carried out for transitions in the nuclei of "1"5"4Sm, "1"5"2Sm and "1"6"6Yb. The Normalised-Peak-to-Gamma method is in general an efficient tool to extract internal conversion coefficients. However, in many cases the required well-known reference transitions are not available. The data analysis steps required to determine absolute internal conversion coefficients with the SAGE spectrometer are presented. In addition, several background suppression methods are introduced and an example of how ancillary detectors can be used to select specific reaction products is given. The results obtained for ground-state band E2 transitions show that the absolute internal conversion coefficients can be extracted using the methods described with a reasonable accuracy. In some cases of less intense transitions only an upper limit for the internal conversion coefficient could be given.

  19. Internal 40K radiation dose to Indians

    International Nuclear Information System (INIS)

    Ranganathan, S.; Someswara Rao, M.; Nagaratnam, A.; Mishra, U.C.

    2002-01-01

    A group of 350 Indians from both sexes (7-65 years) representing different regions of India was studied for internal 40 K radiation dose from the naturally occurring body 40 K, which was measured in the National Institute of Nutrition (NIN) whole-body counter. Although the 40 K radioactivity reached a peak value by 18 years in female (2,412 Bq) and by 20 years in male (3,058 Bq) and then varied inversely with age in both sexes, the radiation dose did not show such a trend. Boys and girls of 11 years had annual effective dose of nearly 185 mSv, which decreased during adolescence (165 mSv), increased to 175 mSv by 18-20 years in adults and decreased progressively on further ageing to 99 mSv in males and 69 mSv in females at 65 years. The observed annual effective dose (175 mSv) of the young adults was close to that of the ICRP Reference Man (176 mSv) and Indian Reference Man (175 mSv). With a mean specific activity of 55 Bq/kg for the subjects and a conversion coefficient close to 3 mSv per annum per Bq/kg, the average annual effective dose from the internal 40 K turned out to be 165 mSv for Indians. (author)

  20. Applicability of dose conversion coefficients of ICRP 74 to Asian adult males: Monte Carlo simulation study

    International Nuclear Information System (INIS)

    Lee, Choonsik; Lee, Choonik; Lee, Jai-Ki

    2007-01-01

    International Commission on Radiological Protection (ICRP) reported comprehensive dose conversion coefficients for adult population, which is exposed to external photon sources in the Publication 74. However, those quantities were calculated from so-called stylized (or mathematical) phantoms composed of simplified mathematical surface equations so that the discrepancy between the phantoms and real human anatomy has been investigated by several authors using Caucasian-based voxel phantoms. To address anatomical and racial limitations of the stylized phantoms, several Asian-based voxel phantoms have been developed by Korean and Japanese investigators, independently. In the current study, photon dose conversion coefficients of ICRP 74 were compared with those from a total of five Asian-based male voxel phantoms, whose body dimensions were almost identical. Those of representative radio-sensitive organs (testes, red bone marrow, colon, lungs, and stomach), and effective dose conversion coefficients were obtained for comparison. Even though organ doses for testes, colon and lungs, and effective doses from ICRP 74 agreed well with those from Asian voxel phantoms within 10%, absorbed doses for red bone marrow and stomach showed significant discrepancies up to 30% which was mainly attributed to difference of phantom description between stylized and voxel phantoms. This study showed that the ICRP 74 dosimetry data, which have been reported to be unrealistic compared to those from Caucasian-based voxel phantoms, are also not appropriate for Asian population

  1. Delimiting coefficient alpha from internal consistency and unidimensionality

    NARCIS (Netherlands)

    Sijtsma, K.

    2015-01-01

    I discuss the contribution by Davenport, Davison, Liou, & Love (2015) in which they relate reliability represented by coefficient α to formal definitions of internal consistency and unidimensionality, both proposed by Cronbach (1951). I argue that coefficient α is a lower bound to reliability and

  2. Dose conversion coefficients for electron exposure of the human eye lens

    International Nuclear Information System (INIS)

    Behrens, R; Dietze, G; Zankl, M

    2009-01-01

    Recent epidemiological studies suggest a rather low dose threshold (below 0.5 Gy) for the induction of a cataract of the eye lens. Some other studies even assume that there is no threshold at all. Therefore, protection measures have to be optimized and current dose limits for the eye lens may be reduced in the future. Two questions arise from this situation: first, which dose quantity is related to the risk of developing a cataract, and second, which personal dose equivalent quantity is appropriate for monitoring this dose quantity. While the dose equivalent quantity H p (0.07) has often been seen as being sufficiently accurate for monitoring the dose to the lens of the eye, this would be questionable in the case when the dose limits were reduced and, thus, it may be necessary to generally use the dose equivalent quantity H p (3) for this purpose. The basis for a decision, however, must be the knowledge of accurate conversion coefficients from fluence to equivalent dose to the lens. This is especially important for low-penetrating radiation, for example, electrons. Formerly published values of conversion coefficients are based on quite simple models of the eye. In this paper, quite a sophisticated model of the eye including the inner structure of the lens was used for the calculations and precise conversion coefficients for electrons with energies between 0.2 MeV and 12 MeV, and for angles of radiation incidence between 0 deg. and 45 deg. are presented. Compared to the values adopted in 1996 by the International Commission on Radiological Protection (ICRP), the new values are up to 1000 times smaller for electron energies below 1 MeV, nearly equal at 1 MeV and above 4 MeV, and by a factor of 1.5 larger at about 1.5 MeV electron energy.

  3. Dose coefficients for radionuclides produced in high energy proton accelerator facilities. Coefficients for radionuclides not listed in ICRP publications

    CERN Document Server

    Kawai, K; Noguchi, H

    2002-01-01

    Effective dose coefficients, the committed effective dose per unit intake, by inhalation and ingestion have been calculated for 304 nuclides, including (1) 230 nuclides with half-lives >= 10 min and their daughters that are not listed in ICRP Publications and (2) 74 nuclides with half-lives < 10 min that are produced in a spallation target. Effective dose coefficients for inhalation of soluble or reactive gases have been calculated for 21 nuclides, and effective dose rates for inert gases have been calculated for 9 nuclides. Dose calculation was carried out using a general-purpose nuclear decay database DECDC developed at JAERI and a decay data library newly compiled from the ENSDF for the nuclides abundantly produced in a spallation target. The dose coefficients were calculated with the computer code DOCAP based on the respiratory tract model and biokinetic model of ICRP. The effective dose rates were calculated by considering both external irradiation from the surrounding cloud and irradiation of the lun...

  4. Reassessment of tritium dose coefficients for the general public

    International Nuclear Information System (INIS)

    Melintescu, A.; Galeriu, D.; Takeda, H.

    2007-01-01

    Concerns of increased risk from tritium intake by humans have been claimed in the past. The arguments concerning the radiobiological effectiveness of tritium, its longer retention in the human body and the presence of tritium in the DNA hydration shell are analysed in this paper. A biokinetic model for tritiated water and organically bound tritium retention in the human body is used, based on a common approach for mammals using energy and hydrogen metabolism and tested separately with animal experiments. Extension to this model to humans considers the increased role of the brain, food quality and unique growth patterns of humans. Various ages and genders for Caucasians are considered. For an intake of tritium in organic forms in the diet, the retention for the female is of about a factor 2 compared with ICRP recommendations. Effective dose coefficients are estimated to be about a factor of 2 to 3 higher than those of the ICRP. (authors)

  5. Internal radiation dose of Indians

    International Nuclear Information System (INIS)

    Ranganathan, S.; Nagaratnam, A.; Sharma, U.C.

    2001-01-01

    The measurement of γ-rays from 40 K by whole-body counting provides a sensitive technique to estimate the body 40 K radioactivity. In India, right from the whole body counter (WBC) of Trombay in the early 1960s to the INMAS WBC of 1970s, some limited information has been available about the internal 40 K of Indians. However, information on 40 K dose with age and sex of Indians is scanty. Therefore, a systematic study was taken up to generate this information

  6. Radon progeny dose conversion coefficients for Chinese males and females

    Energy Technology Data Exchange (ETDEWEB)

    Yu, K.N. E-mail: peter.yu@city.edu.hk; Cheung, T.T.K.; Haque, A.K.M.M.; Nikezic, D.; Lau, B.M.F.; Vucic, D

    2001-07-01

    The airway dimensions for Caucasian males have been scaled by multiplying by factors 0.95 and 0.88 to give those for Chinese males and females, respectively. Employing the most recent data on physical and biological parameters, the radiation doses to the basal and secretory cells due to {alpha} particles from {sup 218}Po and {sup 214}Po, homogeneously distributed in the mucous layer, have been calculated. The emission of {alpha} particles has been simulated by a Monte Carlo method. For both basal and secretory cells, the dose conversion coefficients (DCCs) for physical conditions of sleep, rest, light and heavy exercise, have been obtained for Chinese males and females for unattached progeny, and for attached progeny of diameters 0.02, 0.15, 0.25, 0.30 and 0.50 {mu}m. For basal cells, the coefficients lie in the range 0.69-6.82 mGy/(J s/m{sup 3}) or 8.7-86 mGy/WLM for unattached progeny and in the range 0.045-1.98 mGy/(J s/m{sup 3}) or 0.57-25 mGy/WLM for attached progeny. The corresponding ranges for Caucasian males are 1.27-8.81 mGy/(J s/m{sup 3}) or 16-111 mGy/WLM{sup -1} and 0.05-2.30 mGy/(J s/m{sup 3}) or 0.64-29 mGy/WLM. For secretory cells, the coefficients lie in the range 0.095-16.82 mGy/(J s/m{sup 3}) (1.2-212 mGy/WLM) for unattached progeny and in the range 0.095-6.67 mGy/(J s/m{sup 3}) (1.2-84 mGy/WLM) for attached progeny. The corresponding ranges for Caucasian males are 0.34-21.51 mGy/(J s/m{sup 3}) (4.3-271 mGy/WLM) and 0.1-7.78 mGy/(J s/m{sup 3}) (1.3-98 mGy/WLM). The overall DCCs calculated for a typical home environment are 0.59 and 0.52 mSv/(J s/m{sup 3}) (7.4 and 6.5 mSv/WLM) for Chinese males and females, respectively, which are 80 and 70% of the value, 0.73 mSv/(J s/m{sup 3}) (9.2 mSv/WLM), for Caucasian males.

  7. Radiation doses and risks from internal emitters

    International Nuclear Information System (INIS)

    Harrison, John; Day, Philip

    2008-01-01

    This review updates material prepared for the UK Government Committee Examining Radiation Risks from Internal Emitters (CERRIE) and also refers to the new recommendations of the International Commission on Radiological Protection (ICRP) and other recent developments. Two conclusions from CERRIE were that ICRP should clarify and elaborate its advice on the use of its dose quantities, equivalent and effective dose, and that more attention should be paid to uncertainties in dose and risk estimates and their implications. The new ICRP recommendations provide explanations of the calculation and intended purpose of the protection quantities, but further advice on their use would be helpful. The new recommendations refer to the importance of understanding uncertainties in estimates of dose and risk, although methods for doing this are not suggested. Dose coefficients (Sv per Bq intake) for the inhalation or ingestion of radionuclides are published as reference values without uncertainty. The primary purpose of equivalent and effective dose is to enable the summation of doses from different radionuclides and from external sources for comparison with dose limits, constraints and reference levels that relate to stochastic risks of whole-body radiation exposure. Doses are calculated using defined biokinetic and dosimetric models, including reference anatomical data for the organs and tissues of the human body. Radiation weighting factors are used to adjust for the different effectiveness of different radiation types, per unit absorbed dose (Gy), in causing stochastic effects at low doses and dose rates. Tissue weighting factors are used to take account of the contribution of individual organs and tissues to overall detriment from cancer and hereditary effects, providing a simple set of rounded values chosen on the basis of age- and sex-averaged values of relative detriment. While the definition of absorbed dose has the scientific rigour required of a basic physical quantity

  8. Calculation of effective absorption coefficient for aerosols of internal mixture

    International Nuclear Information System (INIS)

    Xu Bo; Huang Yinbo; Fan Chengyu; Qiao Chunhong

    2012-01-01

    The effective absorption coefficient with time of strong absorbing aerosol made of carbon dusts and water of internal mixture is analyzed, and the influence of different wavelengths and radius ratios on it is discussed. The shorter the wavelength is, the larger the effective absorption coefficient is , and more quickly it increases during 1-100 μs, and the largest increase if 132.65% during 1-100 μs. Different ratios between inner and outer radius have large influence on the effective absorption coefficient. The larger the ratio is, the larger the effective absorption coefficient is, and more quickly it increases during 1-100 μs. The increase of the effective absorption coefficient during 1-100 μs is larger than that during 100-1000 μs, and the largest increase is 138.66% during 1-100 μs. (authors)

  9. Overview of the ICRP/ICRU adult reference computational phantoms and dose conversion coefficients for external idealised exposures

    CERN Document Server

    Endo, A; Zankl, M; Bolch, W E; Eckerman, K F; Hertel, N E; Hunt, J G; Pelliccioni, M; Schlattl, H; Menzel, H-G

    2014-01-01

    This paper reviews the ICRP Publications 110 and 116 describing the reference computational phantoms and dose conversion coefficients for external exposures. The International Commission on Radiological Protection (ICRP) in its 2007 Recommendations made several revisions to the methods of calculation of the protection quantities. In order to implement these recommendations, the DOCAL task group of the ICRP developed computational phantoms representing the reference adult male and female and then calculated a set of dose conversion coefficients for various types of idealised external exposures. This paper focuses on the dose conversion coefficients for neutrons and investigates their relationship with the conversion coefficients of the protection and operational quantities of ICRP Publication 74. Contributing factors to the differences between these sets of conversion coefficients are discussed in terms of the changes in phantoms employed and the radiation and tissue weighting factors.

  10. Dose conversion coefficients for photon exposure of the human eye lens

    Science.gov (United States)

    Behrens, R.; Dietze, G.

    2011-01-01

    In recent years, several papers dealing with the eye lens dose have been published, because epidemiological studies implied that the induction of cataracts occurs even at eye lens doses of less than 500 mGy. Different questions were addressed: Which personal dose equivalent quantity is appropriate for monitoring the dose to the eye lens? Is a new definition of the dose quantity Hp(3) based on a cylinder phantom to represent the human head necessary? Are current conversion coefficients from fluence to equivalent dose to the lens sufficiently accurate? To investigate the latter question, a realistic model of the eye including the inner structure of the lens was developed. Using this eye model, conversion coefficients for electrons have already been presented. In this paper, the same eye model—with the addition of the whole body—was used to calculate conversion coefficients from fluence (and air kerma) to equivalent dose to the lens for photon radiation from 5 keV to 10 MeV. Compared to the values adopted in 1996 by the International Commission on Radiological Protection (ICRP), the new values are similar between 40 keV and 1 MeV and lower by up to a factor of 5 and 7 for photon energies at about 10 keV and 10 MeV, respectively. Above 1 MeV, the new values (calculated without kerma approximation) should be applied in pure photon radiation fields, while the values adopted by the ICRP in 1996 (calculated with kerma approximation) should be applied in case a significant contribution from secondary electrons originating outside the body is present.

  11. Organ and effective dose coefficients for cranial and caudal irradiation geometries: photons

    International Nuclear Information System (INIS)

    Veinot, K.G.; Eckerman, K.F.; Hertel, N.E.

    2016-01-01

    With the introduction of new recommendations of the International Commission on Radiological Protection (ICRP) in Publication 103, the methodology for determining the protection quantity, effective dose, has been modified. The modifications include changes to the defined organs and tissues, the associated tissue weighting factors, radiation weighting factors and the introduction of reference sex-specific computational phantoms. Computations of equivalent doses in organs and tissues are now performed in both the male and female phantoms and the sex-averaged values used to determine the effective dose. Dose coefficients based on the ICRP 103 recommendations were reported in ICRP Publication 116, the revision of ICRP Publication 74 and ICRU Publication 57. The coefficients were determined for the following irradiation geometries: anterior-posterior (AP), posterior-anterior (PA), right and left lateral (RLAT and LLAT), rotational (ROT) and isotropic (ISO). In this work, the methodology of ICRP Publication 116 was used to compute dose coefficients for photon irradiation of the body with parallel beams directed upward from below the feet (caudal) and directed downward from above the head (cranial). These geometries may be encountered in the workplace from personnel standing on contaminated surfaces or volumes and from overhead sources. Calculations of organ and tissue kerma and absorbed doses for caudal and cranial exposures to photons ranging in energy from 10 keV to 10 GeV have been performed using the MCNP6.1 radiation transport code and the adult reference phantoms of ICRP Publication 110. As with calculations reported in ICRP 116, the effects of charged-particle transport are evident when compared with values obtained by using the kerma approximation. At lower energies the effective dose per particle fluence for cranial and caudal exposures is less than AP orientations while above ∼30 MeV the cranial and caudal values are greater. (authors)

  12. Dose conversion coefficients for photon exposure of the human eye lens

    International Nuclear Information System (INIS)

    Behrens, R; Dietze, G

    2011-01-01

    In recent years, several papers dealing with the eye lens dose have been published, because epidemiological studies implied that the induction of cataracts occurs even at eye lens doses of less than 500 mGy. Different questions were addressed: Which personal dose equivalent quantity is appropriate for monitoring the dose to the eye lens? Is a new definition of the dose quantity H p (3) based on a cylinder phantom to represent the human head necessary? Are current conversion coefficients from fluence to equivalent dose to the lens sufficiently accurate? To investigate the latter question, a realistic model of the eye including the inner structure of the lens was developed. Using this eye model, conversion coefficients for electrons have already been presented. In this paper, the same eye model-with the addition of the whole body-was used to calculate conversion coefficients from fluence (and air kerma) to equivalent dose to the lens for photon radiation from 5 keV to 10 MeV. Compared to the values adopted in 1996 by the International Commission on Radiological Protection (ICRP), the new values are similar between 40 keV and 1 MeV and lower by up to a factor of 5 and 7 for photon energies at about 10 keV and 10 MeV, respectively. Above 1 MeV, the new values (calculated without kerma approximation) should be applied in pure photon radiation fields, while the values adopted by the ICRP in 1996 (calculated with kerma approximation) should be applied in case a significant contribution from secondary electrons originating outside the body is present.

  13. New values of some physical interaction coefficients for dose measurements

    International Nuclear Information System (INIS)

    Eisenlohr, H.H.; Zsdanszky, K.

    1986-01-01

    At its 8th meeting in 1985 Section I of the ''Comite Consultatif pour les Etalons de Mesure des Rayonnements lonisants'' (CCEMRI) to the ''Comite International des Poids et Mesures'' (CIPM) has put forward a recommendation on new values of some physical constants to be used for exposure and absorbed dose determinations (see Annex I). Implementation of this recommendation has some impact on the measurement of exposure, air kerma and absorbed dose, and may result in changes in calibration factors of dosimeters. This subject will be discussed in detail at the IAEA Workshop on Calibration Procedures in Dosimetry, to be held in Quito in October 1986. The following information may assist SSDLs in preparing themselves for the expected changes of calibration factors. The recommendation has been caused by new numerical values of some physical constants which have become available recently. The two most important changes concern: a) S m,a , the ratio of the mean restricted collision mass stopping powers of the chamber material to that of air for electrons crossing the cavity, and b) W air /e, the mean energy required to produce an ion pair in air per electron charge, for electrons emitted by radioactive sources or produced by photon absorption

  14. Sediment distribution coefficients (KD) and concentration factors (CF) in fish for natural radionuclides in a pond of a tropical region and their contributions to estimations of internal absorbed dose rate in fish

    International Nuclear Information System (INIS)

    Souza Pereira, Wagner de; Kelecom, Alphonse

    2008-01-01

    Attention has been paid only recently to the protection of biota against radiation effects. Protection is being considered through modeling of the calculation of absorbed dose rate. In these models, the inputs are the fluxes of radionuclides of environmental concern and their resulting distribution between environmental compartments. Such distribution is estimated for dispersion models. In freshwater systems and when fish is used as biomaker, relevant environmental transfer parameters are transfer between sediment and water (sediment distribution coefficients KD, in l kg -1 ), and between water and fish (concentration factor CF, in l kg -1 ). These coefficients are under the influence of a number o physical, chemical and biological factors, and display following the literature a great variability. The present work establishes the KD's and CF's for uranium, thorium, radium and lead for two ponds: one that receives treated effluents from an ore treatment unit (UTM) situated at Pocos de Caldas, Minas Gerais, Brazil and the other pond from the uranium concentration unit (URA) situated at Caetite, Bahia, Brazil, and for fish used as biomarker. It intends also to compare these parameters with the values recommended by IAEA. Depending on considered radionuclide and on the site, CF's (l kg -1 ) observed values were of the same magnitude as, or one order of magnitude lower than recommended by IAEA. KD's (l kg -1 ) observed values were found of the same magnitude as those recommended by IAEA, approximately 10 times lower or up to 100 times higher than recommended by IAEA, again depending on the radionuclides and on the site. It can be concluded that local parameters should be established in order to obtain a more accurate estimative of biota exposition from man activities. (author)

  15. How good are the internal conversion coefficients now?

    International Nuclear Information System (INIS)

    Raman, S.; Nestor, C.W. Jr.; Ichihara, A.; Trzhaskovskaya, M.B.

    2002-01-01

    To fully utilize experimental internal conversion coefficients, one needs a reliable calculation of theoretical values. We have assembled a set of 100 experimental conversion coefficients, 45 α K and 55 α T values, measured with an accuracy of better than 5%, and generated the corresponding theoretical values using two methods, relativistic Hartree-Fock-Slater (RHFS) and relativistic Dirac-Fock (DF). Extensive comparisons of the experimental values with the two sets of theoretical values show that the DF method is clearly superior to the RHFS method in the overall reproduction of the experimental internal conversion coefficients. We discuss in some detail the differences between various versions of these two theoretical approaches, with a view to understanding which of these differences are most critical to obtaining agreement with experiment

  16. Overview of the ICRP/ICRU adult reference computational phantoms and dose conversion coefficients for external idealised exposures

    International Nuclear Information System (INIS)

    Endo, Akira; Petoussi-Henss, Nina; Zankl, Maria; Schlattl, Helmut; Bolch, Wesley E.; Eckerman, Keith F.; Hertel, Nolan E.; Hunt, John G.; Pelliccioni, Maurizio; Menzel, Hans-Georg

    2014-01-01

    This paper reviews the ICRP Publications 110 and 116 describing the reference computational phantoms and dose conversion coefficients for external exposures. The International Commission on Radiological Protection (ICRP) in its 2007 Recommendations made several revisions to the methods of calculation of the protection quantities. In order to implement these recommendations, the DOCAL task group of the ICRP developed computational phantoms representing the reference adult male and female and then calculated a set of dose conversion coefficients for various types of idealised external exposures. This paper focuses on the dose conversion coefficients for neutrons and investigates their relationship with the conversion coefficients of the protection and operational quantities of ICRP Publication 74. Contributing factors to the differences between these sets of conversion coefficients are discussed in terms of the changes in phantoms employed and the radiation and tissue weighting factors. This paper briefly reviews the reference computational phantoms and dose conversion coefficients for external exposures that were published jointly by ICRP and ICRU. Both these publications appeared as a consequence of the ICRP 2007 Recommendations; to implement these recommendations, the ICRP has developed reference computational phantoms representing the adult male and female. These phantoms are used to calculate reference dose conversion coefficients for external and internal sources. Using the reference phantoms and methodology consistent with the 2007 Recommendations, dose conversion coefficients for both effective doses and organ-absorbed doses for various types of idealised external exposures have been calculated. These data sets supersede the existing ICRP/ICRU data sets and expand the particle types and energy ranges. For neutrons, the new effective dose conversion coefficients become smaller compared with those in ICRP74, for energies below hundreds of keV. This is mainly

  17. Dose conversion coefficients based on the Chinese mathematical phantom and MCNP code for external photon irradiation

    International Nuclear Information System (INIS)

    Qiu, R.; Li, J.; Zhang, Z.; Liu, L.; Bi, L.; Ren, L.

    2009-01-01

    A set of conversion coefficients from kerma free-in-air to the organ-absorbed dose are presented for external monoenergetic photon beams from 10 keV to 10 MeV based on the Chinese mathematical phantom, a whole-body mathematical phantom model. The model was developed based on the methods of the Oak Ridge National Laboratory mathematical phantom series and data from the Chinese Reference Man and the Reference Asian Man. This work is carried out to obtain the conversion coefficients based on this model, which represents the characteristics of the Chinese population, as the anatomical parameters of the Chinese are different from those of Caucasians. Monte Carlo simulation with MCNP code is carried out to calculate the organ dose conversion coefficients. Before the calculation, the effects from the physics model and tally type are investigated, considering both the calculation efficiency and precision. In the calculation irradiation conditions include anterior-posterior, posterior-anterior, right lateral, left lateral, rotational and isotropic geometries. Conversion coefficients from this study are compared with those recommended in the Publication 74 of International Commission on Radiological Protection (ICRP74) since both the sets of data are calculated with mathematical phantoms. Overall, consistency between the two sets of data is observed and the difference for more than 60% of the data is below 10%. However, significant deviations are also found, mainly for the superficial organs (up to 65.9%) and bone surface (up to 66%). The big difference of the dose conversion coefficients for the superficial organs at high photon energy could be ascribed to kerma approximation for the data in ICRP74. Both anatomical variations between races and the calculation method contribute to the difference of the data for bone surface. (authors)

  18. Dose conversion coefficients based on the Chinese mathematical phantom and MCNP code for external photon irradiation.

    Science.gov (United States)

    Qiu, Rui; Li, Junli; Zhang, Zhan; Liu, Liye; Bi, Lei; Ren, Li

    2009-02-01

    A set of conversion coefficients from kerma free-in-air to the organ-absorbed dose are presented for external monoenergetic photon beams from 10 keV to 10 MeV based on the Chinese mathematical phantom, a whole-body mathematical phantom model. The model was developed based on the methods of the Oak Ridge National Laboratory mathematical phantom series and data from the Chinese Reference Man and the Reference Asian Man. This work is carried out to obtain the conversion coefficients based on this model, which represents the characteristics of the Chinese population, as the anatomical parameters of the Chinese are different from those of Caucasians. Monte Carlo simulation with MCNP code is carried out to calculate the organ dose conversion coefficients. Before the calculation, the effects from the physics model and tally type are investigated, considering both the calculation efficiency and precision. In the calculation irradiation conditions include anterior-posterior, posterior-anterior, right lateral, left lateral, rotational and isotropic geometries. Conversion coefficients from this study are compared with those recommended in the Publication 74 of International Commission on Radiological Protection (ICRP74) since both the sets of data are calculated with mathematical phantoms. Overall, consistency between the two sets of data is observed and the difference for more than 60% of the data is below 10%. However, significant deviations are also found, mainly for the superficial organs (up to 65.9%) and bone surface (up to 66%). The big difference of the dose conversion coefficients for the superficial organs at high photon energy could be ascribed to kerma approximation for the data in ICRP74. Both anatomical variations between races and the calculation method contribute to the difference of the data for bone surface.

  19. Practical applications of internal dose calculations

    International Nuclear Information System (INIS)

    Carbaugh, E.H.

    1994-06-01

    Accurate estimates of intake magnitude and internal dose are the goal for any assessment of an actual intake of radioactivity. When only one datum is available on which to base estimates, the choices for internal dose assessment become straight-forward: apply the appropriate retention or excretion function, calculate the intake, and calculate the dose. The difficulty comes when multiple data and different types of data become available. Then practical decisions must be made on how to interpret conflicting data, or how to adjust the assumptions and techniques underlying internal dose assessments to give results consistent with the data. This article describes nine types of adjustments which can be incorporated into calculations of intake and internal dose, and then offers several practical insights to dealing with some real-world internal dose puzzles

  20. DOSE COEFFICIENTS FOR LIVER CHEMOEMBOLISATION PROCEDURES USING MONTE CARLO CODE.

    Science.gov (United States)

    Karavasilis, E; Dimitriadis, A; Gonis, H; Pappas, P; Georgiou, E; Yakoumakis, E

    2016-12-01

    The aim of the present study is the estimation of radiation burden during liver chemoembolisation procedures. Organ dose and effective dose conversion factors, normalised to dose-area product (DAP), were estimated for chemoembolisation procedures using a Monte Carlo transport code in conjunction with an adult mathematical phantom. Exposure data from 32 patients were used to determine the exposure projections for the simulations. Equivalent organ (H T ) and effective (E) doses were estimated using individual DAP values. The organs receiving the highest amount of doses during these exams were lumbar spine, liver and kidneys. The mean effective dose conversion factor was 1.4 Sv Gy -1 m -2 Dose conversion factors can be useful for patient-specific radiation burden during chemoembolisation procedures. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. Development of Monte Carlo simulations to provide scanner-specific organ dose coefficients for contemporary CT

    Science.gov (United States)

    Jansen, Jan T. M.; Shrimpton, Paul C.

    2016-07-01

    The ImPACT (imaging performance assessment of CT scanners) CT patient dosimetry calculator is still used world-wide to estimate organ and effective doses (E) for computed tomography (CT) examinations, although the tool is based on Monte Carlo calculations reflecting practice in the early 1990’s. Subsequent developments in CT scanners, definitions of E, anthropomorphic phantoms, computers and radiation transport codes, have all fuelled an urgent need for updated organ dose conversion factors for contemporary CT. A new system for such simulations has been developed and satisfactorily tested. Benchmark comparisons of normalised organ doses presently derived for three old scanners (General Electric 9800, Philips Tomoscan LX and Siemens Somatom DRH) are within 5% of published values. Moreover, calculated normalised values of CT Dose Index for these scanners are in reasonable agreement (within measurement and computational uncertainties of  ±6% and  ±1%, respectively) with reported standard measurements. Organ dose coefficients calculated for a contemporary CT scanner (Siemens Somatom Sensation 16) demonstrate potential deviations by up to around 30% from the surrogate values presently assumed (through a scanner matching process) when using the ImPACT CT Dosimetry tool for newer scanners. Also, illustrative estimates of E for some typical examinations and a range of anthropomorphic phantoms demonstrate the significant differences (by some 10’s of percent) that can arise when changing from the previously adopted stylised mathematical phantom to the voxel phantoms presently recommended by the International Commission on Radiological Protection (ICRP), and when following the 2007 ICRP recommendations (updated from 1990) concerning tissue weighting factors. Further simulations with the validated dosimetry system will provide updated series of dose coefficients for a wide range of contemporary scanners.

  2. Foetal dose conversion coefficients for ICRP-compliant pregnant models from idealised proton exposures

    International Nuclear Information System (INIS)

    Taranenko, V.; Xu, X. G.

    2009-01-01

    Protection of pregnant women and their foetus against external proton irradiations poses a unique challenge. Assessment of foetal dose due to external protons in galactic cosmic rays and as secondaries generated in aircraft walls is especially important during high-altitude flights. This paper reports a set of fluence to absorbed dose conversion coefficients for the foetus and its brain for external monoenergetic proton beams of six standard configurations (the antero-posterior, the postero-anterior, the right lateral, the left lateral, the rotational and the isotropic). The pregnant female anatomical definitions at each of the three gestational periods (3, 6 and 9 months) are based on newly developed RPI-P series of models whose organ masses were matched within 1% with the International Commission on Radiological Protection reference values. Proton interactions and the transport of secondary particles were carefully simulated using the Monte Carlo N-Particle extended code (MCNPX) and the phantoms consisting of several million voxels at 3 mm resolution. When choosing the physics models in the MCNPX, it was found that the advanced Cascade-Exciton intranuclear cascade model showed a maximum of 9% foetal dose increase compared with the default model combination at intermediate energies below 5 GeV. Foetal dose results from this study are tabulated and compared with previously published data that were based on simplified anatomy. The comparison showed a strong dependence upon the source geometry, energy and gestation period: The dose differences are typically less than 20% for all sources except ISO where systematically 40-80% of higher doses were observed. Below 200 MeV, a larger discrepancy in dose was found due to the Bragg peak shift caused by different anatomy. The tabulated foetal doses represent the latest and most detailed study to date offering a useful set of data to improve radiation protection dosimetry against external protons. (authors)

  3. Organ dose conversion coefficients for voxel models of the reference male and female from idealized photon exposures

    International Nuclear Information System (INIS)

    Schlattl, H; Zankl, M; Petoussi-Henss, N

    2007-01-01

    A new series of organ equivalent dose conversion coefficients for whole body external photon exposure is presented for a standardized couple of human voxel models, called Rex and Regina. Irradiations from broad parallel beams in antero-posterior, postero-anterior, left- and right-side lateral directions as well as from a 360 deg. rotational source have been performed numerically by the Monte Carlo transport code EGSnrc. Dose conversion coefficients from an isotropically distributed source were computed, too. The voxel models Rex and Regina originating from real patient CT data comply in body and organ dimensions with the currently valid reference values given by the International Commission on Radiological Protection (ICRP) for the average Caucasian man and woman, respectively. While the equivalent dose conversion coefficients of many organs are in quite good agreement with the reference values of ICRP Publication 74, for some organs and certain geometries the discrepancies amount to 30% or more. Differences between the sexes are of the same order with mostly higher dose conversion coefficients in the smaller female model. However, much smaller deviations from the ICRP values are observed for the resulting effective dose conversion coefficients. With the still valid definition for the effective dose (ICRP Publication 60), the greatest change appears in lateral exposures with a decrease in the new models of at most 9%. However, when the modified definition of the effective dose as suggested by an ICRP draft is applied, the largest deviation from the current reference values is obtained in postero-anterior geometry with a reduction of the effective dose conversion coefficient by at most 12%

  4. Organ dose conversion coefficients for voxel models of the reference male and female from idealized photon exposures

    Science.gov (United States)

    Schlattl, H.; Zankl, M.; Petoussi-Henss, N.

    2007-04-01

    A new series of organ equivalent dose conversion coefficients for whole body external photon exposure is presented for a standardized couple of human voxel models, called Rex and Regina. Irradiations from broad parallel beams in antero-posterior, postero-anterior, left- and right-side lateral directions as well as from a 360° rotational source have been performed numerically by the Monte Carlo transport code EGSnrc. Dose conversion coefficients from an isotropically distributed source were computed, too. The voxel models Rex and Regina originating from real patient CT data comply in body and organ dimensions with the currently valid reference values given by the International Commission on Radiological Protection (ICRP) for the average Caucasian man and woman, respectively. While the equivalent dose conversion coefficients of many organs are in quite good agreement with the reference values of ICRP Publication 74, for some organs and certain geometries the discrepancies amount to 30% or more. Differences between the sexes are of the same order with mostly higher dose conversion coefficients in the smaller female model. However, much smaller deviations from the ICRP values are observed for the resulting effective dose conversion coefficients. With the still valid definition for the effective dose (ICRP Publication 60), the greatest change appears in lateral exposures with a decrease in the new models of at most 9%. However, when the modified definition of the effective dose as suggested by an ICRP draft is applied, the largest deviation from the current reference values is obtained in postero-anterior geometry with a reduction of the effective dose conversion coefficient by at most 12%.

  5. CALCULATION OF FLUENCE-TO-EFFECTIVE DOSE CONVERSION COEFFICIENTS FOR THE OPERATIONAL QUANTITY PROPOSED BY ICRU RC26.

    Science.gov (United States)

    Endo, Akira

    2017-07-01

    Fluence-to-effective dose conversion coefficients have been calculated for photons, neutrons, electrons, positrons, protons, muons, pions and helium ions for various incident angles of radiations. The aim of this calculation is to provide a set of conversion coefficients to the Report Committee 26 (RC26) of the International Commission on Radiation Units and Measurements (ICRU) for use in defining personal dose equivalent for individual monitoring. The data sets comprise effective dose conversion coefficients for incident angles of radiations from 0° to ±90° in steps of 15° and at ±180°. Conversion coefficients for rotational, isotropic, superior hemisphere semi-isotropic and inferior hemisphere semi-isotropic irradiations are also included. Numerical data of the conversion coefficients are presented as supplementary data. The conversion coefficients are used to define the personal dose equivalent, which is being considered by the ICRU RC26, as the operational quantity for individual monitoring. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  6. Evaluation of dose conversion coefficients for external exposure using Taiwanese reference man and woman

    International Nuclear Information System (INIS)

    Chang, S.J.; Hung, S.Y.; Liu, Y.L.; Jiang, S.H.; Wu, J.

    2015-01-01

    Reference man has been widely used for external and internal dose evaluation of radiation protection. The parameters of the mathematical model of organs suggested by the International Commission of Radiological Protection (ICRP) are adopted from the average data of Caucasians. However, the organ masses of Asians are significantly different from the data of Caucasians, leading to potentially dosimetric errors. In this study, a total of 40 volunteers whose heights and weights corresponded to the statistical average of Taiwanese adults were recruited. Magnetic resonance imaging was performed, and T2-weighted images were acquired. The Taiwanese reference man and woman were constructed according to the measured organ masses. The dose conversion coefficients (DCFs) for anterior-posterior (AP), posterior-anterior (PA), right lateral (RLAT) and left lateral (LLAT) irradiation geometries were simulated. For the Taiwanese reference man, the average differences of the DCFs compared with the results of ICRP-74 were 7.6, 5.1 and 11.1 % for 0.1, 1 and 10 MeV photons irradiated in the AP direction. The maximum difference reached 51.7 % for the testes irradiated by 10 MeV photons. The size of the trunk, the volume and the geometric position of organs can cause a significant impact on the DCFs for external exposure of radiation. The constructed Taiwanese reference man and woman can be used in radiation protection to increase the accuracy of dose evaluation for the Taiwanese population. (authors)

  7. Dose conversion coefficients for high-energy photons, electrons, neutrons and protons

    International Nuclear Information System (INIS)

    Sakamoto, Yukio

    2005-01-01

    Dose conversion coefficients for photons, electrons and neutrons based on new ICRP recommendations were cited in the ICRP Publication 74, but the energy ranges of these data were limited and there are no data for high energy radiations produced in accelerator facilities. For the purpose of designing the high intensity proton accelerator facilities at JAERI, the dose evaluation code system of high energy radiations based on the HERMES code was developed and the dose conversion coefficients of effective dose were evaluated for photons, neutrons and protons up to 10 GeV, and electrons up to 100 GeV. The dose conversion coefficients of effective dose equivalent were also evaluated using quality factors to consider the consistency between radiation weighting factors and Q-L relationship. The effective dose conversion coefficients obtained in this work were in good agreement with those recently evaluated by using FLUKA code for photons and electrons with all energies, and neutrons and protons below 500 MeV. There were some discrepancy between two data owing to the difference of cross sections in the nuclear reaction models. The dose conversion coefficients of effective dose equivalents for high energy radiations based on Q-L relation in ICRP Publication 60 were evaluated only in this work. The previous comparison between effective dose and effective dose equivalent made it clear that the radiation weighting factors for high energy neutrons and protons were overestimated and the modification was required. (author)

  8. Absorbed dose conversion coefficients for embryo and foetus in neutron fields

    International Nuclear Information System (INIS)

    Chen, J.

    2007-01-01

    The Monte Carlo code MCNPX has been used to determine mean absorbed doses to the embryo and foetus when the mother is exposed to neutron fields. There are situations, such as on-board aircraft, where high-energy neutrons are often peaked in top down (TOP) direction. In addition to previous publications for standard irradiation geometries, this study provides absorbed dose conversion coefficients for the embryo of 8 weeks and the foetus of 3, 6 or 9 months at TOP irradiation geometry. The conversion coefficients are compared with the coefficients in isotropic irradiation (ISO). With increasing neutron energies, the conversion coefficients in TOP irradiation become dominant. A set of conversion coefficients is constructed from the higher value in either ISO or TOP irradiation at a given neutron energy. In cases where the irradiation geometry is not adequately known, this set of conversion coefficients can be used in a conservative dose assessment for embryo and foetus in neutron fields. (authors)

  9. Dose conversion coefficients calculated using a series of adult Japanese voxel phantoms against external photon exposure

    International Nuclear Information System (INIS)

    Sato, Kaoru; Endo, Akira; Saito, Kimiaki

    2008-10-01

    This report presents a complete set of conversion coefficients of organ doses and effective doses calculated for external photon exposure using five Japanese adult voxel phantoms developed at the Japan Atomic Energy Agency (JAEA). At the JAEA, high-resolution Japanese voxel phantoms have been developed to clarify the variation of organ doses due to the anatomical characteristics of Japanese, and three male phantoms (JM, JM2 and Otoko) and two female phantoms (JF and Onago) have been constructed up to now. The conversion coefficients of organ doses and effective doses for the five voxel phantoms have been calculated for six kinds of idealized irradiation geometries from monoenergetic photons ranging from 0.01 to 10 MeV using EGS4, a Monte Carlo code for the simulation of coupled electron-photon transport. The dose conversion coefficients are given as absorbed dose and effective dose per unit air-kerma free-in-air, and are presented in tables and figures. The calculated dose conversion coefficients are compared with those of voxel phantoms based on the Caucasian and the recommended values in ICRP74 in order to discuss (1) variation of organ dose due to the body size and individual anatomy, such as position and shape of organs, and (2) effect of posture on organ doses. The present report provides valuable data to study the influence of the body characteristics of Japanese upon the organ doses and to discuss developing reference Japanese and Asian phantoms. (author)

  10. Outlines of ICRP publication 74 and new dose conversion coefficients for external radiation

    International Nuclear Information System (INIS)

    Yamaguchi, Yasuhiro

    1998-01-01

    Combined task group of ICRP and ICRU reported the ICRP Publication 74 (1996) which is a summary report of their collection, analysis and evaluation of many data and dose conversion coefficients. Concerning the new coefficients, the author described this review as follows: History until Publication 74. Doses recommended at present: for protection quantity, the mean absorption dose of organ and tissue, equivalent dose and effective dose and for operational quantity, the ambient dose equivalent, directional dose equivalent and individual dose equivalent. Changes which can have an influence on the dose evaluation; introduction of radiation weighting factor (WR), changing of tissue weighting factor (WR), changing of the equation for Q-L relation and updating of physical data. New dose conversion coefficients; for photon, neutron and electron. Comparison of new and present coefficients; concerning the quality factor Q, particularly for neutron Q. New relations of protection and operational quantities; for field and individual monitoring. General conclusion of Publication 74. The Publication gives a certain direction for problems in evaluation of external exposure dose which have been discussed since the ICRP Fundamental Recommendation 1990 was issued. However, there still remain many problems especially in validity of the WR and of equation for Q-L relation. (K.H.)

  11. Radiation dose estimation and mass attenuation coefficients of cement samples used in Turkey

    International Nuclear Information System (INIS)

    Damla, N.; Cevik, U.; Kobya, A.I.; Celik, A.; Celik, N.; Van Grieken, R.

    2010-01-01

    Different cement samples commonly used in building construction in Turkey have been analyzed for natural radioactivity using gamma-ray spectrometry. The mean activity concentrations observed in the cement samples were 52, 40 and 324 Bq kg -1 for 226 Ra, 232 Th and 40 K, respectively. The measured activity concentrations for these radionuclides were compared with the reported data of other countries and world average limits. The radiological hazard parameters such as radium equivalent activities (Ra eq ), gamma index (I γ ) and alpha index (I α ) indices as well as terrestrial absorbed dose and annual effective dose rate were calculated and compared with the international data. The Ra eq values of cement are lower than the limit of 370 Bq kg -1 , equivalent to a gamma dose of 1.5 mSv y -1 . Moreover, the mass attenuation coefficients were determined experimentally and calculated theoretically using XCOM in some cement samples. Also, chemical compositions analyses of the cement samples were investigated.

  12. Data base of dose coefficients called ecrin-V1-internet reference handbook; Base de donnees de coefficients de dose ecrin-V1-internet manuel de reference

    Energy Technology Data Exchange (ETDEWEB)

    Perrin, M.L

    2003-07-01

    The objective of this data base is to dispose on a only computer medium the values of radiation doses allowing to guarantee the tracing and the coherence of radiation doses received by man. These data are usable to evaluate the risks in the frame of studies or expertise. They include the doses coming from external irradiations, internal contamination by inhalation or ingestion and receive by workers or public. The definitions and reference values come from international publications (the list is given). (N.C.)

  13. ESTIMATION OF THE CONVERSION COEFFICIENTS FROM DOSE-AREA PRODUCT TO EFFECTIVE DOSE FOR BARIUM MEAL EXAMINATIONS FOR ADULT PATIENTS

    Directory of Open Access Journals (Sweden)

    A. V. Vodovatov

    2018-01-01

    Full Text Available Fluoroscopic examinations of the upper gastro-intestinal tract and, especially, barium meal examinations, are commonly performed in a majority of hospitals. These examinations are associated both with substantial individual patient doses and contribution to the collective dose from medical exposure. Effective dose estimation for this type of examinations is complicated due to: 1 the necessity to simulate the moving X-ray irradiation field; 2 differences in study structure for the individual patients; 3 subjectivity of the operators; and 4 differences in the X-ray equipment. The aim of the current study was to estimate conversion coefficients from dose-area product to effective dose for barium meal examinations for the over couch and under couch exposure conditions. The study was based on data collected in the X-ray unit of the surgical department of the St-Petersburg Mariinsky hospital. A model of patient exposure during barium meal examination was developed based on the collected data on fluoroscopy protocols and adult patient irradiation geometry. Conversion coefficients were calculated using PCXMC 2.0 software. Complete examinations were converted into a set of typical fluoroscopy phases and X-ray images, specified by the examined anatomical region and the projection of patient exposure. Conversion coefficients from dose-area product to effective dose were calculated for each phase of the examination and for the complete examination. The resulting values of the conversion coefficients are comparable with published data. Variations in the absolute values of the conversion coefficients can be explained by differences in clinical protocols, models for the estimation of the effective dose and parameters of barium meal examinations. The proposed approach for estimation of effective dose considers such important features of fluoroscopic examinations as: 1 non-uniform structure of examination, 2 significant movement of the X-ray tube within a single

  14. An overview of coefficient alpha and a reliability matrix for estimating adequacy of internal consistency coefficients with psychological research measures.

    Science.gov (United States)

    Ponterotto, Joseph G; Ruckdeschel, Daniel E

    2007-12-01

    The present article addresses issues in reliability assessment that are often neglected in psychological research such as acceptable levels of internal consistency for research purposes, factors affecting the magnitude of coefficient alpha (alpha), and considerations for interpreting alpha within the research context. A new reliability matrix anchored in classical test theory is introduced to help researchers judge adequacy of internal consistency coefficients with research measures. Guidelines and cautions in applying the matrix are provided.

  15. Dose conversion coefficients for paediatric CT examinations with automatic tube current modulation

    International Nuclear Information System (INIS)

    Schlattl, H; Zankl, M; Becker, J; Hoeschen, C

    2012-01-01

    A common dose-saving technique used in modern CT devices is automatic tube current modulation (TCM), which was originally designed to also reduce the dose in paediatric CT patients. In order to be able to deduce detailed organ doses of paediatric models, dose conversion coefficients normalized to CTDI vol for an eight-week-old baby and seven- and eight-year-old children have been computed accounting for TCM. The relative difference in organ dose conversion coefficients with and without TCM is for many organs and examinations less than 10%, but can in some cases amount up to 30%, e.g., for the thyroid in the chest CT of the seven-year-old child. Overall, the impact of TCM on the conversion coefficients increases with increasing age. Besides TCM, also the effect of collimation and tube voltage on organ dose conversion coefficients has been investigated. It could be shown that the normalization to CTDI vol leads to conversion coefficients that can in most cases be considered to be independent of collimation and tube voltage. (paper)

  16. Radiation dose estimation and mass attenuation coefficients of marble used in Turkey

    International Nuclear Information System (INIS)

    Cevik, U.; Damla, N.; Kobya, A.I.; Celik, A.; Kara, A.

    2010-01-01

    In this study the natural radioactivity in marble samples used in Turkey was measured by means of gamma spectrometry. The results showed that the specific activities of 226 Ra, 232 Th and 40 K ranged from 10 to 92 Bq kg -1 , from 4 to 122 Bq kg -1 and from 28 to 676 Bq kg -1 , respectively. The radiological hazards in marble samples due to the natural radioactivity were inferred from calculations of radium equivalent activities (Ra eq ), indoor absorbed dose rate in air values, the annual effective dose and gamma and alpha indexes. These radiological parameters were evaluated and compared with the internationally recommended values. The measurements showed that marble samples used in Turkey have low level of natural radioactivity; therefore, the use of these types of marble in dwellings is safe for inhabitants. Mass attenuation coefficients (μ/ρ) were obtained both experimentally and theoretically for different marble samples produced in Turkey by using gamma-ray transmission method. Experimental values showed a good agreement with the theoretical values.

  17. Conversion coefficients for determining organ doses in paediatric pelvis and hip joint radiography

    International Nuclear Information System (INIS)

    Seidenbusch, Michael C.; Schneider, Karl

    2014-01-01

    Knowledge of organ and effective doses achieved during paediatric X-ray examinations is an important prerequisite for assessment of radiation burden to the patient. Conversion coefficients for reconstruction of organ and effective doses from entrance doses for pelvis and hip joint radiographs of 0-, 1-, 5-, 10-, 15- and 30-year-old patients are provided regarding the Guidelines of Good Radiographic Technique of the European Commission. Using the personal computer program PCXMC developed by the Finnish Centre for Radiation and Nuclear Safety (Saeteilyturvakeskus STUK), conversion coefficients for conventional pelvis and hip joint radiographs were calculated by performing Monte Carlo simulations in mathematical hermaphrodite phantom models representing patients of different ages. The clinical variation of radiation field settings was taken into consideration by defining optimal and suboptimal standard field settings. Conversion coefficients for the reconstruction of organ doses in about 40 organs and tissues from measured entrance doses during pelvis and hip joint radiographs of 0-, 1-, 5-, 10-, 15- and 30-year-old patients were calculated for the standard sagittal beam projection and the standard focus detector distance of 115 cm. The conversion coefficients presented can be used for organ dose assessments from entrance doses measured during pelvis and hip joint radiographs of children and young adults with all field settings within the optimal and suboptimal standard field settings. (orig.)

  18. Photon dose conversion coefficients for the human teeth in standard irradiation geometries

    Energy Technology Data Exchange (ETDEWEB)

    Ulanovsky, A; Wieser, A; Zankl, M; Jacob, P

    2005-07-01

    Photon dose conversion coefficients for the human tooth materials are computed in energy range from 0.01 to 10 MeV by the Monte Carlo method. The voxel phantom Golem of the human body with newly defined tooth region and a modified version of the EGS4 code have been used to compute the coefficients for 30 tooth cells with different locations and materials. The dose responses are calculated for cells representing buccal and lingual enamel layers. The computed coefficients demonstrate a strong dependence on energy and geometry of the radiation source and a weaker dependence on location of the enamel voxels. For isotropic and rotational radiation fields the enamel dose does not show a significant dependence on tooth sample locations. The computed coefficients are used to convert from absorbed dose in teeth to organ dose or to integral air kerma. Examples of integral conversion factors from enamel dose to air kerma are given for several photon fluences specific for the Mayak reprocessing plant in Russia. The integral conversion factors are strongly affected by the energy and angular distributions of photon fluence, which are important characteristics of an exposure scenario for reconstruction of individual occupational doses. (orig.)

  19. Deuterons at energies of 10 MeV to 1 TeV: Conversion coefficients for fluence-to-absorbed dose, equivalent dose, effective dose and gray equivalent, calculated using Monte Carlo radiation transport code MCNPX 2.7.C

    International Nuclear Information System (INIS)

    Copeland, K.; Parker, D. E.; Friedberg, W.

    2011-01-01

    Conversion coefficients were calculated for fluence-to-absorbed dose, fluence-to-equivalent dose, fluence-to-effective dose and fluence-to-gray equivalent for isotropic exposure of an adult female and an adult male to deuterons ( 2 H + ) in the energy range 10 MeV -1 TeV (0.01-1000 GeV). Coefficients were calculated using the Monte Carlo transport code MCNPX 2.7.C and BodyBuilder TM 1.3 anthropomorphic phantoms. Phantoms were modified to allow calculation of the effective dose to a Reference Person using tissues and tissue weighting factors from 1990 and 2007 recommendations of the International Commission on Radiological Protection (ICRP) and gray equivalent to selected tissues as recommended by the National Council on Radiation Protection and Measurements. Coefficients for the equivalent and effective dose incorporated a radiation weighting factor of 2. At 15 of 19 energies for which coefficients for the effective dose were calculated, coefficients based on ICRP 1990 and 2007 recommendations differed by < 3 %. The greatest difference, 47 %, occurred at 30 MeV. (authors)

  20. Background internal dose rates of earthworm and arthropod species in the forests of Aomori, Japan

    International Nuclear Information System (INIS)

    Yoshihito Ohtsuka; Yuichi Takaku; Shun'ichi Hisamatsu

    2015-01-01

    In this study, we measured the concentrations of several natural radionuclides in samples of one earthworm species and 11 arthropod species collected from four coniferous forests in Rokkasho, Aomori Prefecture, Japan, and we assessed the background internal radiation dose rate for each species. Dose rates were calculated by using the radionuclide concentrations in the samples and dose conversion coefficients obtained from the literature. The mean internal dose rate in the earthworm species was 0.28 μGy h -1 , and the mean internal dose rates in the arthropod species ranged between 0.036 and 0.69 μGy h -1 . (author)

  1. Pancreatic enzyme replacement therapy in cystic fibrosis: dose, variability and coefficient of fat absorption.

    Science.gov (United States)

    Calvo-Lerma, Joaquim; Martínez-Barona, Sandra; Masip, Etna; Fornés, Victoria; Ribes-Koninckx, Carmen

    2017-10-01

    Pancreatic enzyme replacement therapy (PERT) remains a backbone in the nutritional treatment of cystic fibrosis. Currently, there is a lack of an evidence-based tool that allows dose adjustment. To date, no studies have found an association between PERT dose and fat absorption. Therefore, the aim of the study was to assess the influence of both the PERT dose and the variability in this dose on the coefficient of fat absorption (CFA). This is a retrospective longitudinal study of 16 pediatric patients (192 food records) with three consecutive visits to the hospital over a twelve-month period. Dietary fat intake and PERT were assessed via a four-day food record and fat content in stools was determined by means of a three-day stool sample collection. A beta regression model was built to explain the association between the CFA and the interaction between the PERT dose (lipase units [LU]/g dietary fat) and the variability in the PERT dose (standard deviation [SD]). The coefficient of fat absorption increased with the PERT dose when the variability in the dose was low. In contrast, even at the highest PERT dose values, the CFA decreased when the variability was high. The confidence interval suggested an association, although the analysis was not statistically significant. The variability in the PERT dose adjustment should be taken into consideration when performing studies on PERT efficiency. A clinical goal should be the maintenance of a constant PERT dose rather than trying to obtain an optimal value.

  2. Measurement and evaluation of internal dose

    International Nuclear Information System (INIS)

    Lee, Tae Young; Chang, S. Y.; Lee, J. I.; Song, M. Y.

    2006-01-01

    This report describes the contents and results for implementation of internal radiation monitoring programme, measurement of uranium present in lung by lung counter and assessment of committed effective dose for radiation workers of the KNFC. The aim of radiation protection was achieved by implementing this activity

  3. Dose distribution following selective internal radiation therapy

    International Nuclear Information System (INIS)

    Fox, R.A.; Klemp, P.F.; Egan, G.; Mina, L.L.; Burton, M.A.; Gray, B.N.

    1991-01-01

    Selective Internal Radiation Therapy is the intrahepatic arterial injection of microspheres labelled with 90Y. The microspheres lodge in the precapillary circulation of tumor resulting in internal radiation therapy. The activity of the 90Y injected is managed by successive administrations of labelled microspheres and after each injection probing the liver with a calibrated beta probe to assess the dose to the superficial layers of normal tissue. Predicted doses of 75 Gy have been delivered without subsequent evidence of radiation damage to normal cells. This contrasts with the complications resulting from doses in excess of 30 Gy delivered from external beam radiotherapy. Detailed analysis of microsphere distribution in a cubic centimeter of normal liver and the calculation of dose to a 3-dimensional fine grid has shown that the radiation distribution created by the finite size and distribution of the microspheres results in an highly heterogeneous dose pattern. It has been shown that a third of normal liver will receive less than 33.7% of the dose predicted by assuming an homogeneous distribution of 90Y

  4. Internal conversion coefficients of high multipole transitions: Experiment and theories

    International Nuclear Information System (INIS)

    Gerl, J.; Vijay Sai, K.; Sainath, M.; Gowrishankar, R.; Venkataramaniah, K.

    2008-01-01

    A compilation of the available experimental internal conversion coefficients (ICCs), α T , α K , α L , and ratios K/L and K/LM of high multipole (L > 2) transitions for a number of elements in the range 21 ≤ Z ≤ 94 is presented. Our listing of experimental data includes 194 data sets on 110 E3 transitions, 10 data sets on 6 E4 transitions, 11 data sets on 7 E5 transitions, 38 data sets on 21 M3 transitions, and 132 data sets on 68 M4 transitions. Data with less than 10% experimental uncertainty have been selected for comparison with the theoretical values of Hager and Seltzer [R.S. Hager, E.C. Seltzer, Nucl. Data Tables A 4 (1968) 1], Rosel et al. [F. Roesel, H.M. Fries, K. Alder, H.C. Pauli, At. Data Nucl. Data Tables 21 (1978) 91], and BRICC. The relative percentage deviations (%Δ) have been calculated for each of the above theories and the averages (%Δ-bar) are estimated. The Band et al. [I.M. Band, M.B. Trzhaskovskaya, C.W. Nestor Jr., P.O. Tikkanen, S. Raman, At. Data Nucl. Data Tables 81 (2002) 1] tables, using the BRICC interpolation code, are seen to give theoretical ICCs closest to experimental values

  5. Impact on Dose Coefficients Calculated with ICRP Adult Mesh-type Reference Computational Phantoms

    Energy Technology Data Exchange (ETDEWEB)

    Yeom, Yeon Soo; Nguyen, Thang Tat; Choi, Chan Soo; Lee, Han Jin; Han, Hae Gin; Han, Min Cheol; Shin, Bang Ho; Kim, Chan Hyeong [Dept. of Nuclear Engineering, Hanyang University, Seoul (Korea, Republic of)

    2017-04-15

    In 2016, the International Commission on Radiological Protection (ICRP) formulated a new Task Group (TG) (i.e., TG 103) within Committee 2. The ultimate aim of the TG 103 is to develop the mesh-type reference computational phantoms (MRCPs) that can address dosimetric limitations of the currently used voxel-type reference computational phantoms (VRCPs) due to their limited voxel resolutions. The objective of the present study is to investigate dosimetric impact of the adult MRCPs by comparing dose coefficients (DCs) calculated with the MRCPs for some external and internal exposure cases and the reference DCs in ICRP Publications 116 and 133 that were produced with the adult VRCPs. In the present study, the DCs calculated with the adult MRCPs for some exposure cases were compared with the values in ICRP Publications 116 and 133. This comparison shows that in general the MRCPs provide very similar DCs for uncharged particles, but for charged particles provide significantly different DCs due to the improvement of the MRCPs.

  6. Rapid radiological characterization method based on the use of dose coefficients

    International Nuclear Information System (INIS)

    Dulama, C.; Toma, Al.; Dobrin, R.; Valeca, M.

    2010-01-01

    Intervention actions in case of radiological emergencies and exploratory radiological surveys require rapid methods for the evaluation of the range and extent of contamination. When simple and homogeneous radionuclide composition characterize the radioactive contamination, surrogate measurements can be used to reduce the costs implied by laboratory analyses and to speed-up the process of decision support. A dose-rate measurement-based methodology can be used in conjunction with adequate dose coefficients to assess radionuclide inventories and to calculate dose projections for various intervention scenarios. The paper presents the results obtained for dose coefficients in some particular exposure geometries and the methodology used for deriving dose rate guidelines from activity concentration upper levels specified as contamination limits. All calculations were performed by using the commercial software MicroShield from Grove Software Inc. A test case was selected as to meet the conditions from EPA Federal Guidance Report no. 12 (FGR12) concerning the evaluation of dose coefficients for external exposure from contaminated soil and the obtained results were compared to values given in the referred document. The geometries considered as test cases are: contaminated ground surface; - infinite extended homogeneous surface contamination and soil contaminated to a depth of 15 cm. As shown by the results, the values agree within 50% relative difference for most of the cases. The greatest discrepancies were observed for depth contamination simulation and in the case of radionuclides with complicated gamma emission and this is due to the different approach from MicroShield and FGR12. A case study is presented for validation of the methodology, where both dose rate measurements and laboratory analyses were performed on an extended quasi-homogeneous NORM contamination. The dose rate estimations obtained by applying the dose coefficients to the radionuclide concentrations

  7. Dose coefficients for public exposition; Coeficientes de dose para exposicao ao publico

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    This Regulation refers to the requirements of the Regulation CNEN-NN.3.01 'Basic Guidelines for Radiation Protection', to be applied to the dose calculus with the objective of verification according to the limits and restrictions of dose and reference levels of the public individuals, expressed in its section 5

  8. Measurement of conversion coefficients between air Kerma and personal dose equivalent and backscatter factors for diagnostic X-ray beams

    International Nuclear Information System (INIS)

    Rosado, Paulo Henrique Goncalves

    2008-01-01

    Two sets of quantities are import in radiological protection: the protection and operational quantities. Both sets can be related to basic physical quantities such as kerma through conversion coefficients. For diagnostic x-ray beams the conversion coefficients and backscatter factors have not been determined yet, those parameters are need for calibrating dosimeters that will be used to determine the personal dose equivalent or the entrance skin dose. Conversion coefficients between air kerma and personal dose equivalent and backscatter factors were experimentally determined for the diagnostic x-ray qualities RQR and RQA recommended by the International Electrotechnical Commission (IEC). The air kerma in the phantom and the mean energy of the spectrum were measured for such purpose. Harshaw LiF-100H thermoluminescent dosemeters (TLD) were used for measurements after being calibrated against an 180 cm 3 Radcal Corporation ionization chamber traceable to a reference laboratory. A 300 mm x 300 mm x 150 mm polymethylmethacrylate (PMMA) slab phantom was used for deep-dose measurements. Tl dosemeters were placed in the central axis of the x-ray beam at 5, 10, 15, 25 and 35 mm depth in the phantom upstream the beam direction Another required parameter for determining the conversion coefficients from was the mean energy of the x-ray spectrum. The spectroscopy of x-ray beams was done with a CdTe semiconductor detector that was calibrated with 133 Ba, 241 Am and 57 Co radiation sources. Measurements of the x-ray spectra were carried out for all RQR and RQA IEC qualities. Corrections due to the detector intrinsic efficiency, total energy absorption, escape fraction of the characteristic x-rays, Compton effect and attenuation in the detector were done aiming an the accurate determination of the mean energy. Measured x-ray spectra were corrected with the stripping method by using these response functions. The typical combined standard uncertainties of conversion coefficients and

  9. Simulation codes to evcaluate dose conversion coefficients for hadrons over 10 GeV

    International Nuclear Information System (INIS)

    Sato, T.; Tsuda, S.; Sakamoto, Y.; Yamaguchi, Y.; Niita, K.

    2002-01-01

    The conversion coefficients from fluence to effective dose for high energy hadrons are indispensable for various purposes such as accelerator shielding design and dose evaluation in space mission. Monte Carlo calculation code HETC-3STEP was used to evaluate dose conversion coefficients for neutrons and protons up to 10 GeV with an anthropomorphic model. The scaling model was incorporated in the code for simulation of high energy nuclear reactions. However, the secondary particle energy spectra predicted by the model were not smooth for nuclear reactions over several GeV. We attempted, therefore, to simulate transportation of such high energy particles by two newly developed Monte Carlo simulation codes: one is HETC-3STEP including the model used in EVENTQ instead of the scaling model, and the other is NMTC/JAM. By comparing calculated cross sections by these codes with experimental data for high energy nuclear reactions, it was found that NMTC/JAM had a better agreement with the data. We decided, therefore, to adopt NMTC/JAM for evaluation of dose conversion coefficients for hadrons with energies over 10 GeV. The effective dose conversion coefficients for high energy neutrons and protons evaluated by NMTC/JAM were found to be close to those by the FLUKA code

  10. Comparison of photon organ and effective dose coefficients for PIMAL stylized phantom in bent positions in standard irradiation geometries

    Energy Technology Data Exchange (ETDEWEB)

    Dewji, Shaheen; Hiller, Mauritius [Oak Ridge National Laboratory, Center for Radiation Protection Knowledge, Environmental Sciences Division, Oak Ridge, TN (United States); Reed, K.L. [Georgia Institute of Technology, Nuclear and Radiological Engineering Program, Atlanta, GA (United States)

    2017-08-15

    Computational phantoms with articulated arms and legs have been constructed to enable the estimation of radiation dose in different postures. Through a graphical user interface, the Phantom wIth Moving Arms and Legs (PIMAL) version 4.1.0 software can be employed to articulate the posture of a phantom and generate a corresponding input deck for the Monte Carlo N-Particle (MCNP) radiation transport code. In this work, photon fluence-to-dose coefficients were computed using PIMAL to compare organ and effective doses for a stylized phantom in the standard upright position with those for phantoms in realistic work postures. The articulated phantoms represent working positions including fully and half bent torsos with extended arms for both the male and female reference adults. Dose coefficients are compared for both the upright and bent positions across monoenergetic photon energies: 0.05, 0.1, 0.5, 1.0, and 5.0 MeV. Additionally, the organ doses are compared across the International Commission on Radiological Protection's standard external radiation exposure geometries: antero-posterior, postero-anterior, left and right lateral, and isotropic (AP, PA, LLAT, RLAT, and ISO). For the AP and PA irradiation geometries, differences in organ doses compared to the upright phantom become more profound with increasing bending angles and have doses largely overestimated for all organs except the brain in AP and bladder in PA. In LLAT and RLAT irradiation geometries, energy deposition for organs is more likely to be underestimated compared to the upright phantom, with no overall change despite increased bending angle. The ISO source geometry did not cause a significant difference in absorbed organ dose between the different phantoms, regardless of position. Organ and effective fluence-to-dose coefficients are tabulated. In the AP geometry, the effective dose at the 45 bent position is overestimated compared to the upright phantom below 1 MeV by as much as 27% and 82% in the

  11. Manual on internal dose computation and reporting

    International Nuclear Information System (INIS)

    Sawant, Pramilla D.; Sawant, Jyoti V.; Gurg, R.P.; Rudran, Kamala; Gupta, V.K.; Abani, M.C.

    1999-05-01

    Whole body counting and bioassay measurement are carried out for estimation of radioactivity content in the whole body or in a particular organ/tissue of interest. These measurements are routinely carried out for occupational workers at nuclear power plants, reprocessing plants, radiochemical laboratories, radioisotope laboratories and radioactive waste management facilities to evaluate individual internal dose due to 3 H, 60 Co, 90 Sr, 137 Cs, transuranics and other isotopes of interest. This manual is prepared to provide guidelines for computation of intake, committed equivalent dose and committed effective dose from direct measurement of tissue and/or body content of radioactivity for 60 Co, 131 I, and 137 Cs employing in-vivo monitoring procedures and/or bioassay measurements only. Bioassay measurements are used for determination of 90 Sr in the body since it is a pure beta emitter. This manual can be used as a ready reckoner for assessment of radiation dose due to internal contamination of occupational workers as estimated using above techniques in the middle and back-end of the nuclear fuel cycle operations. The methodology used in computation of dose is based on the principles and biokinetic models given by ICRP. Recording level recommended in the manual is 0.6 mSv for both, routine as well as special monitoring, which is lower than 1 mSv recommended by ICRP (ICRP-75, 1997) for individual routine monitoring and 0.66 mSv for special monitoring. The Annual Limit on Intake is taken equivalent to Annual Effective Dose Limit of 20 mSv as prescribed by the Atomic Energy Regulatory Board (AERB), India. (author)

  12. Correspondence of the ICRP database of dose coefficients (1996) to 2007 recommendations of the ICRP

    International Nuclear Information System (INIS)

    Kadatskaya, M.M.

    2012-01-01

    The new IAEA international safety standards, issued in 2011, recommend in practical implementation of the 2007 Recommendations of the ICRP continue to use dosimetric database developed in 1996. This article presents method and results of the calculation of committed effective dose of internal exposure in accordance with the new definition of this quantity given in 2007 Recommendations of the ICRP. It is shown that in the control of internal doses in accordance with the 2007 Recommendations of the ICRP it is allowed to use dose factors which were released in 1996. (authors)

  13. Calculation of age-dependent dose conversion coefficients for radionuclides uniformly distributed in air

    International Nuclear Information System (INIS)

    Hung, Tran Van; Satoh, Daiki; Takahashi, Fumiaki; Tsuda, Shuichi; Endo, Akira; Saito, Kimiaki; Yamaguchi, Yasuhiro

    2005-02-01

    Age-dependent dose conversion coefficients for external exposure to photons emitted by radionuclides uniformly distributed in air were calculated. The size of the source region in the calculation was assumed to be effectively semi-infinite in extent. Firstly, organ doses were calculated with a series of age-specific MIRD-5 type phantoms using MCNP code, a Monte Carlo transport code. The calculations were performed for mono-energetic photon sources of twelve energies from 10 keV to 5 MeV and for phantoms of newborn, 1, 5, 10 and 15 years, and adult. Then, the effective doses to the different age-phantoms from the mono-energetic photon sources were estimated based on the obtained organ doses. The calculated effective doses were used to interpolate the conversion coefficients of the effective doses for 160 radionuclides, which are important for dose assessment of nuclear facilities. In the calculation, energies and intensities of emitted photons from radionuclides were taken from DECDC, a recent compilation of decay data for radiation dosimetry developed at JAERI. The results are tabulated in the form of effective dose per unit concentration and time (Sv per Bq s m -3 ). (author)

  14. Effective dose conversion coefficients for X-ray radiographs of the chest and the abdomen

    Energy Technology Data Exchange (ETDEWEB)

    Lima, F.R.A. [Centro regional de Ciencias Nucleares, CRCN/CNEN, Rua Conego Barata, 999, Tamarineira, Recife, PE (Brazil); Kramer, R.; Vieira, J.W.; Khoury, H.J. [Departamento de Energia Nuclear, DEN/UFPE, Cidade Universitaria, Recife, PE (Brazil)]. E-mail: falima@cnen.gov.br

    2004-07-01

    The recently developed MAX (Male Adult voXel) and the FAXht (Female Adult voXel) head and trunk phantoms have been used to calculate organ and tissue equivalent dose conversion coefficients for X-ray radiographs of the chest and the abdomen as a function of source and field parameters, like voltage, filtration, field size, focus-to-skin distance, etc. Based on the equivalent doses to twenty three organs and tissues at risk, the effective dose has been determined and compared with corresponding data for others phantoms. The influence of different radiation transport codes, different tissue compositions and different human anatomies have been investigated separately. (Author)

  15. Effective dose conversion coefficients for X-ray radiographs of the chest and the abdomen

    International Nuclear Information System (INIS)

    Lima, F.R.A.; Kramer, R.; Vieira, J.W.; Khoury, H.J.

    2004-01-01

    The recently developed MAX (Male Adult voXel) and the FAXht (Female Adult voXel) head and trunk phantoms have been used to calculate organ and tissue equivalent dose conversion coefficients for X-ray radiographs of the chest and the abdomen as a function of source and field parameters, like voltage, filtration, field size, focus-to-skin distance, etc. Based on the equivalent doses to twenty three organs and tissues at risk, the effective dose has been determined and compared with corresponding data for others phantoms. The influence of different radiation transport codes, different tissue compositions and different human anatomies have been investigated separately. (Author)

  16. Pancreatic enzyme replacement therapy in cystic fibrosis: dose, variability and coefficient of fat absorption

    Directory of Open Access Journals (Sweden)

    Joaquim Calvo-Lerma

    Full Text Available Objectives: Pancreatic enzyme replacement therapy (PERT remains a backbone in the nutritional treatment of cystic fibrosis. Currently, there is a lack of an evidence-based tool that allows dose adjustment. To date, no studies have found an association between PERT dose and fat absorption. Therefore, the aim of the study was to assess the influence of both the PERT dose and the variability in this dose on the coefficient of fat absorption (CFA. Methods: This is a retrospective longitudinal study of 16 pediatric patients (192 food records with three consecutive visits to the hospital over a twelve-month period. Dietary fat intake and PERT were assessed via a four-day food record and fat content in stools was determined by means of a three-day stool sample collection. A beta regression model was built to explain the association between the CFA and the interaction between the PERT dose (lipase units [LU]/g dietary fat and the variability in the PERT dose (standard deviation [SD]. Results: The coefficient of fat absorption increased with the PERT dose when the variability in the dose was low. In contrast, even at the highest PERT dose values, the CFA decreased when the variability was high. The confidence interval suggested an association, although the analysis was not statistically significant. Conclusion: The variability in the PERT dose adjustment should be taken into consideration when performing studies on PERT efficiency. A clinical goal should be the maintenance of a constant PERT dose rather than trying to obtain an optimal value.

  17. Measurement of secondary cosmic radiation and calculation of associated dose conversion coefficients for humans

    International Nuclear Information System (INIS)

    Simmer, Gregor

    2012-01-01

    Due to secondary cosmic radiation (SCR), pilots and flight attendants receive elevated effective doses at flight altitudes. For this reason, since 2003 aircrew members are considered as occupationally exposed, in Germany. This work deals with the calculation of dose conversion coefficients (DCC) for protons, neutrons, electrons, positrons, photons and myons, which are crucial for estimation of effective dose from SCR. For the first time, calculations were performed combining Geant4 - a Monte Carlo code developed at CERN - with the voxel phantoms for the reference female and male published in 2008 by ICRP and ICRU. Furthermore, measurements of neutron fluence spectra - which contribute the major part to the effective dose of SCR - were carried out at the Environmental Research Station Schneefernerhaus (UFS) located at 2650 m above sea level nearby the Zugspitze mountain, Germany. These measured neutron spectra, and additionally available calculated spectra, were then folded with the DCC calculated in this work, and effective dose rates for different heights were calculated.

  18. Tritons at energies of 10 MeV to 1 TeV: Conversion coefficients for fluence-to-absorbed dose, equivalent dose, effective dose, and gray equivalent, calculated using Monte Carlo radiation transport code MCNPX 2.7.C

    International Nuclear Information System (INIS)

    Copeland, K.; Parker, D. E.; Friedberg, W.

    2010-01-01

    Conversion coefficients were calculated for fluence-to-absorbed dose, fluence-to-equivalent dose, fluence-to-effective dose and fluence-to-gray equivalent for isotropic exposure of an adult female and an adult male to tritons ( 3 H + ) in the energy range of 10 MeV to 1 TeV (0.01-1000 GeV). Coefficients were calculated using Monte Carlo transport code MCNPX 2.7.C and BodyBuilder TM 1.3 anthropomorphic phantoms. Phantoms were modified to allow calculation of effective dose to a Reference Person using tissues and tissue weighting factors from 1990 and 2007 recommendations of the International Commission on Radiological Protection (ICRP) and calculation of gray equivalent to selected tissues as recommended by the National Council on Radiation Protection and Measurements. At 15 of the 19 energies for which coefficients for effective dose were calculated, coefficients based on ICRP 2007 and 1990 recommendations differed by less than 3%. The greatest difference, 43%, occurred at 30 MeV. Published by Oxford Univ. Press on behalf of the US Government 2010. (authors)

  19. The local skin dose conversion coefficients of electrons, protons and alpha particles calculated using the Geant4 code.

    Science.gov (United States)

    Zhang, Bintuan; Dang, Bingrong; Wang, Zhuanzi; Wei, Wei; Li, Wenjian

    2013-10-01

    The skin tissue-equivalent slab reported in the International Commission on Radiological Protection (ICRP) Publication 116 to calculate the localised skin dose conversion coefficients (LSDCCs) was adopted into the Monte Carlo transport code Geant4. The Geant4 code was then utilised for computation of LSDCCs due to a circular parallel beam of monoenergetic electrons, protons and alpha particles electrons and alpha particles are found to be in good agreement with the results using the MCNPX code of ICRP 116 data. The present work thus validates the LSDCC values for both electrons and alpha particles using the Geant4 code.

  20. Data base of dose coefficients called ecrin-V1-internet reference handbook

    International Nuclear Information System (INIS)

    Perrin, M.L.

    2003-07-01

    The objective of this data base is to dispose on a only computer medium the values of radiation doses allowing to guarantee the tracing and the coherence of radiation doses received by man. These data are usable to evaluate the risks in the frame of studies or expertise. They include the doses coming from external irradiations, internal contamination by inhalation or ingestion and receive by workers or public. The definitions and reference values come from international publications (the list is given). (N.C.)

  1. Organ and Effective Dose Coefficients for Cranial and Caudal Irradiation Geometries: Neutrons

    Science.gov (United States)

    Veinot, K. G.; Eckerman, K. F.; Hertel, N. E.; Hiller, M. M.

    2017-09-01

    With the introduction of new recommendations by ICRP Publication 103, the methodology for determining the protection quantity, effective dose, has been modified. The modifications include changes to the defined organs and tissues, the associated tissue weighting factors, radiation weighting factors, and the introduction of reference sex-specific computational phantoms (ICRP Publication 110). Computations of equivalent doses in organs and tissues are now performed in both the male and female phantoms and the sex-averaged values used to determine the effective dose. Dose coefficients based on the ICRP 103 recommendations were reported in ICRP Publication 116, the revision of ICRP Publication 74 and ICRU Publication 57. The coefficients were determined for the following irradiation geometries: anterior-posterior (AP), posterior-anterior (PA), right and left lateral (RLAT and LLAT), rotational (ROT), and isotropic (ISO). In this work, the methodology of ICRP Publication 116 was used to compute dose coefficients for neutron irradiation of the body with parallel beams directed upward from below the feet (caudal) and directed downward from above the head (cranial). These geometries may be encountered in the workplace from personnel standing on contaminated surfaces or volumes and from overhead sources. Calculations of organ and tissue absorbed doses for caudal and cranial exposures to neutrons ranging in energy from 10-9 MeV to 10 GeV have been performed using the MCNP6 radiation transport code and the adult reference voxel phantoms of ICRP Publication 110. At lower energies the effective dose per particle fluence for cranial and caudal exposures is less than AP orientations while above about 30 MeV the cranial and caudal values are greater.

  2. Monitoring requirements for assessment of internal dose

    International Nuclear Information System (INIS)

    Eckerman, K.F.

    1985-01-01

    Data obtained by routine personnel monitoring is usually not a sufficient basis for estimation of dose. Collected data must be interpreted carefully and supplemented with appropriate information before reasonably accurate estimates of dose (i.e., accurate enough to indicate whether or nor personnel are exposed in excess of recommended limits) can be developed. When the exposure is of sufficient magnitude that a rather precise estimate of dose is needed, the health physicist will bring to bear on the problem other, more refined, methods of dosimetry. These might include a reconstruction of the incident and, for internal emitters, an extensive series of in vivo measurements or analyses of excreta. Thus, cases of special significance must often be evaluated using techniques and resources beyond those routinely employed. This is not a criticism of most routine monitoring programs. These programs are usually carefully designed in a manner commensurate with the degree of exposure routinely encountered and the requirement of a practical program of radiation protection. 10 refs

  3. Critical Dose of Internal Organs Internal Exposure - 13471

    Energy Technology Data Exchange (ETDEWEB)

    Grigoryan, G.; Amirjanyan, A. [Nuclear and Radiation Safety Centre (Armenia); Grigoryan, N. [Yerevan State Medical University 4Tigran Mets,375010 Yerevan (Armenia)

    2013-07-01

    The health threat posed by radionuclides has stimulated increased efforts to developed characterization on the biological behavior of radionuclides in humans in all ages. In an effort motivated largely by the Chernobyl nuclear accident, the International Commission on Radiological Protection (ICRP) is assembling a set of age specific biokinetic models for environmentally important radioelements. Radioactive substances in the air, mainly through the respiratory system and digestive tract, is inside the body. Radioactive substances are unevenly distributed in various organs and tissues. Therefore, the degree of damage will depend not only on the dose of radiation have but also on the critical organ, which is the most accumulation of radioactive substances, which leads to the defeat of the entire human body. The main objective of radiation protection, to avoid exceeding the maximum permissible doses of external and internal exposure of a person to prevent the physical and genetic damage people. The maximum tolerated dose (MTD) of radiation is called a dose of radiation a person in uniform getting her for 50 years does not cause changes in the health of the exposed individual and his progeny. The following classification of critical organs, depending on the category of exposure on their degree of sensitivity to radiation: First group: the whole body, gonads and red bone marrow; Second group: muscle, fat, liver, kidney, spleen, gastrointestinal tract, lungs and lens of the eye; The third group: bone, thyroid and skin; Fourth group: the hands, forearms, feet. MTD exposure whole body, gonads and bone marrow represent the maximum exposures (5 rem per year) experienced by people in their normal activities. The purpose of this article is intended dose received from various internal organs of the radionuclides that may enter the body by inhalation, and gastrointestinal tract. The biokinetic model describes the time dependent distribution and excretion of different

  4. Calculation of neutron fluence to dose equivalent conversion coefficients using GEANT4

    International Nuclear Information System (INIS)

    Ribeiro, Rosane M.; Santos, Denison de S.; Queiroz Filho, Pedro P. de; Mauricio, CLaudia L.P.; Silva, Livia K. da; Pessanha, Paula R.

    2014-01-01

    Fluence to dose equivalent conversion coefficients provide the basis for the calculation of area and personal monitors. Recently, the ICRP has started a revision of these coefficients, including new Monte Carlo codes for benchmarking. So far, little information is available about neutron transport below 10 MeV in tissue-equivalent (TE) material performed with Monte Carlo GEANT4 code. The objective of this work is to calculate neutron fluence to personal dose equivalent conversion coefficients, H p (10)/Φ, with GEANT4 code. The incidence of monoenergetic neutrons was simulated as an expanded and aligned field, with energies ranging between thermal neutrons to 10 MeV on the ICRU slab of dimension 30 x 30 x 15 cm 3 , composed of 76.2% of oxygen, 10.1% of hydrogen, 11.1% of carbon and 2.6% of nitrogen. For all incident energy, a cylindrical sensitive volume is placed at a depth of 10 mm, in the largest surface of the slab (30 x 30 cm 2 ). Physic process are included for neutrons, photons and charged particles, and calculations are made for neutrons and secondary particles which reach the sensitive volume. Results obtained are thus compared with values published in ICRP 74. Neutron fluence in the sensitive volume was calculated for benchmarking. The Monte Carlo GEANT4 code was found to be appropriate to calculate neutron doses at energies below 10 MeV correctly. (author)

  5. Dose Rate and Mass Attenuation Coefficients of Gamma Ray for Concretes

    CERN Document Server

    Abdel-Latif, A A; Kansouh, W A; El-Sayed, F H

    2003-01-01

    This work is concerned with the study of the leakage gamma ray dose and mass attenuation coefficients for ordinary, basalt and dolomite concretes made from local ores. Concretes under investigation were constructed from gravel, basalt and dolomite ores, and then reconstructed with the addition of 3% steel fibers by weight. Measurements were carried out using a collimated beam from sup 6 sup 0 Co gamma ray source and sodium iodide (3x3) crystal with the genie 2000 gamma spectrometer. The obtained fluxes were transformed to gamma ray doses and displayed in the form of gamma ray dose rates distribution. The displayed curves were used to estimate the linear attenuation coefficients (mu), the relaxation lengths (lambda), half value layer (t sub 1 /2) and tenth value layer (t sub 1 /10). Also, The total mass attenuation coefficients of gamma ray have been calculated to the concerned concretes using XCOM (version 3.1) program and database elements cross sections from Z=1 to 100 at energies from 10 keV to 100 MeV. In...

  6. Dose coefficients in pediatric and adult abdominopelvic CT based on 100 patient models

    Science.gov (United States)

    Tian, Xiaoyu; Li, Xiang; Segars, W. Paul; Frush, Donald P.; Paulson, Erik K.; Samei, Ehsan

    2013-12-01

    Recent studies have shown the feasibility of estimating patient dose from a CT exam using CTDIvol-normalized-organ dose (denoted as h), DLP-normalized-effective dose (denoted as k), and DLP-normalized-risk index (denoted as q). However, previous studies were limited to a small number of phantom models. The purpose of this work was to provide dose coefficients (h, k, and q) across a large number of computational models covering a broad range of patient anatomy, age, size percentile, and gender. The study consisted of 100 patient computer models (age range, 0 to 78 y.o.; weight range, 2-180 kg) including 42 pediatric models (age range, 0 to 16 y.o.; weight range, 2-80 kg) and 58 adult models (age range, 18 to 78 y.o.; weight range, 57-180 kg). Multi-detector array CT scanners from two commercial manufacturers (LightSpeed VCT, GE Healthcare; SOMATOM Definition Flash, Siemens Healthcare) were included. A previously-validated Monte Carlo program was used to simulate organ dose for each patient model and each scanner, from which h, k, and q were derived. The relationships between h, k, and q and patient characteristics (size, age, and gender) were ascertained. The differences in conversion coefficients across the scanners were further characterized. CTDIvol-normalized-organ dose (h) showed an exponential decrease with increasing patient size. For organs within the image coverage, the average differences of h across scanners were less than 15%. That value increased to 29% for organs on the periphery or outside the image coverage, and to 8% for distributed organs, respectively. The DLP-normalized-effective dose (k) decreased exponentially with increasing patient size. For a given gender, the DLP-normalized-risk index (q) showed an exponential decrease with both increasing patient size and patient age. The average differences in k and q across scanners were 8% and 10%, respectively. This study demonstrated that the knowledge of patient information and CTDIvol/DLP values may

  7. Dose coefficients in pediatric and adult abdominopelvic CT based on 100 patient models

    International Nuclear Information System (INIS)

    Tian, Xiaoyu; Samei, Ehsan; Li, Xiang; Segars, W Paul; Frush, Donald P; Paulson, Erik K

    2013-01-01

    Recent studies have shown the feasibility of estimating patient dose from a CT exam using CTDI vol -normalized-organ dose (denoted as h), DLP-normalized-effective dose (denoted as k), and DLP-normalized-risk index (denoted as q). However, previous studies were limited to a small number of phantom models. The purpose of this work was to provide dose coefficients (h, k, and q) across a large number of computational models covering a broad range of patient anatomy, age, size percentile, and gender. The study consisted of 100 patient computer models (age range, 0 to 78 y.o.; weight range, 2–180 kg) including 42 pediatric models (age range, 0 to 16 y.o.; weight range, 2–80 kg) and 58 adult models (age range, 18 to 78 y.o.; weight range, 57–180 kg). Multi-detector array CT scanners from two commercial manufacturers (LightSpeed VCT, GE Healthcare; SOMATOM Definition Flash, Siemens Healthcare) were included. A previously-validated Monte Carlo program was used to simulate organ dose for each patient model and each scanner, from which h, k, and q were derived. The relationships between h, k, and q and patient characteristics (size, age, and gender) were ascertained. The differences in conversion coefficients across the scanners were further characterized. CTDI vol -normalized-organ dose (h) showed an exponential decrease with increasing patient size. For organs within the image coverage, the average differences of h across scanners were less than 15%. That value increased to 29% for organs on the periphery or outside the image coverage, and to 8% for distributed organs, respectively. The DLP-normalized-effective dose (k) decreased exponentially with increasing patient size. For a given gender, the DLP-normalized-risk index (q) showed an exponential decrease with both increasing patient size and patient age. The average differences in k and q across scanners were 8% and 10%, respectively. This study demonstrated that the knowledge of patient information and CTDI vol

  8. Helions at energies of 10 MeV to 1 TeV: Conversion coefficients for fluence-to-absorbed dose, equivalent dose, effective dose and gray equivalent, calculated using Monte Carlo radiation transport code MCNPX 2.7.C

    International Nuclear Information System (INIS)

    Copeland, K.; Parker, D. E.; Friedberg, W.

    2010-01-01

    Conversion coefficients were calculated for fluence-to-absorbed dose, fluence-to-equivalent dose, fluence-to-effective dose and fluence-to-gray equivalent, for isotropic exposure of an adult male and an adult female to helions ( 3 He 2+ ) in the energy range of 10 MeV to 1 TeV (0.01-1000 GeV). Calculations were performed using Monte Carlo transport code MCNPX 2.7.C and BodyBuilder TM 1.3 anthropomorphic phantoms modified to allow calculation of effective dose using tissues and tissue weighting factors from either the 1990 or 2007 recommendations of the International Commission on Radiological Protection (ICRP), and gray equivalent to selected tissues as recommended by the National Council on Radiation Protection and Measurements. At 15 of the 19 energies for which coefficients for effective dose were calculated, coefficients based on ICRP 2007 and 1990 recommendations differed by less than 2%. The greatest difference, 62%, occurred at 100 MeV. Published by Oxford Univ. Press on behalf of the U.S. Government 2010. (authors)

  9. Application of ICRP recommendations relevant to internal dose

    International Nuclear Information System (INIS)

    Cowser, K.E.; Snyder, W.S.; Struxness, E.G.

    1969-01-01

    The intent of this paper is to review several of the basic concepts of radiation protection (with emphasis on internal dose) currently recommended by the International Commission on radiological Protection (ICRP), to summarize the assumptions and methods used in the calculation of internal dose, and to illustrate by example the practical application of the pertinent guidelines. Two broad subject areas are considered: (1) standards of radiation protection and (2) bases of internal dose estimation. Topics discussed within the framework of radiation protection standards include maximum permissible dose, categories of radiation exposure, maximum permissible dose commitment, simultaneous internal and external exposure, multiple organ exposure, and size of the exposed group. Discussion of internal dose estimation is limited to selected items that include the body burden of radionuclides and the calculation of absorbed dose, the dose equivalent, the derivation of maximum permissible concentration (MPC), the relationship of stable element intake to the MPC, and short term and chronic exposure situations. (author)

  10. Application of ICRP recommendations relevant to internal dose

    Energy Technology Data Exchange (ETDEWEB)

    Cowser, K E; Snyder, W S; Struxness, E G [Health Physics Division, Oak Ridge National Laboratory, Oak Ridge, TN (United States)

    1969-07-01

    The intent of this paper is to review several of the basic concepts of radiation protection (with emphasis on internal dose) currently recommended by the International Commission on radiological Protection (ICRP), to summarize the assumptions and methods used in the calculation of internal dose, and to illustrate by example the practical application of the pertinent guidelines. Two broad subject areas are considered: (1) standards of radiation protection and (2) bases of internal dose estimation. Topics discussed within the framework of radiation protection standards include maximum permissible dose, categories of radiation exposure, maximum permissible dose commitment, simultaneous internal and external exposure, multiple organ exposure, and size of the exposed group. Discussion of internal dose estimation is limited to selected items that include the body burden of radionuclides and the calculation of absorbed dose, the dose equivalent, the derivation of maximum permissible concentration (MPC), the relationship of stable element intake to the MPC, and short term and chronic exposure situations. (author)

  11. Determination of the conversion coefficient for ambient dose equivalent, H(10), from air kerma measurements

    International Nuclear Information System (INIS)

    Gonzalez J, F.; Alvarez R, J. T.

    2015-09-01

    Namely the operational magnitudes can be determined by the product of a conversion coefficient by exposure air kerma or fluence, etc. In particular in Mexico for the first time is determined the conversion coefficient (Cc) for operational magnitude Environmental Dose Equivalent H(10) by thermoluminescence dosimetry (TLD) technique. First 30 TLD-100 dosimeters are calibrated in terms of air kerma, then these dosimeters are irradiated inside a sphere ICRU type of PMMA and with the aid of theory cavity the absorbed dose in PMMA is determined at a depth of 10 mm within the sphere D PMMA (10), subsequently absorbed dose to ICRU tissue is corrected and the dose equivalent H(10) is determined. The Cc is determined as the ratio of H(10)/K a obtaining a value of 1.20 Sv Gy -1 with a u c = 3.66%, this being consistent with the published value in ISO-4037-3 of 1.20 Sv Gy -1 with a u c = 2%. (Author)

  12. Internal friction and linear expansion coefficient in zirconium and cobalt within the range of phase transitions

    International Nuclear Information System (INIS)

    Boyarskij, S.V.

    1986-01-01

    Experimental results are presented for internal friction and linear expansion coefficient at zirconium and cobalt in the temperature range from 440 K to the point of the phase transition of the first kind (1138 K for Zr and 706 for Co). Anomalous changes of the internal friction and linear expansion coefficient in the phase transition region are found. Theoretical considerations are given to explain the sharp decrease of the internal friction as temperature approaches the phase transition point

  13. Assessment of internal doses in emergency situations

    Energy Technology Data Exchange (ETDEWEB)

    Rahola, T.; Muikku, M. [Radiation and Nuclear Safety Authority - STUK (Finland); Falk, R.; Johansson, J. [Swedish Radiation Protection Authority - SSI (Sweden); Liland, A.; Thorshaug, S. [NRPA (Norway)

    2006-04-15

    The need for assessing internal radiation doses in emergency situations was demonstrated after accidents in Brazil, Ukraine and other countries. Lately more and more concern has been expressed regarding malevolent use of radiation and radioactive materials. The scenarios for such use are more difficult to predict than for nuclear power plant or weapons accidents. Much of the results of the work done in the IRADES project can be adopted for use in various accidental situations involving radionuclides that are not addressed in this report. If an emergency situation occurs in only one or a few of the Nordic countries, experts from the other countries could be called upon to assist in monitoring. A big advantage is then our common platform. In the Nordic countries much work has been put down on quality assurance of measurements and on training of dose assessment calculations. Attention to this was addressed at the internal dosimetry course in October 2005. Nordic emergency preparedness exercises have so far not included training of direct measurements of people in the early phase of an emergency. The aim of the IRADES project was to improve the preparedness especially for thyroid measurements. The modest financial support did not enable the participants to make big efforts but certainly acted as a much appreciated reminder of the importance of being prepared also to handle situations with malevolent use of radioactive materials. It was left to each country to decide to which extent to improve the practical skills. There is still a need for detailed national implementation plans. Measurement strategies need to be developed in each country separately taking into account national regulations, local circumstances and resources. End users of the IRADES report are the radiation protection authorities. (au)

  14. Assessment of internal doses in emergency situations

    International Nuclear Information System (INIS)

    Rahola, T.; Muikku, M.; Falk, R.; Johansson, J.; Liland, A.; Thorshaug, S.

    2006-04-01

    The need for assessing internal radiation doses in emergency situations was demonstrated after accidents in Brazil, Ukraine and other countries. Lately more and more concern has been expressed regarding malevolent use of radiation and radioactive materials. The scenarios for such use are more difficult to predict than for nuclear power plant or weapons accidents. Much of the results of the work done in the IRADES project can be adopted for use in various accidental situations involving radionuclides that are not addressed in this report. If an emergency situation occurs in only one or a few of the Nordic countries, experts from the other countries could be called upon to assist in monitoring. A big advantage is then our common platform. In the Nordic countries much work has been put down on quality assurance of measurements and on training of dose assessment calculations. Attention to this was addressed at the internal dosimetry course in October 2005. Nordic emergency preparedness exercises have so far not included training of direct measurements of people in the early phase of an emergency. The aim of the IRADES project was to improve the preparedness especially for thyroid measurements. The modest financial support did not enable the participants to make big efforts but certainly acted as a much appreciated reminder of the importance of being prepared also to handle situations with malevolent use of radioactive materials. It was left to each country to decide to which extent to improve the practical skills. There is still a need for detailed national implementation plans. Measurement strategies need to be developed in each country separately taking into account national regulations, local circumstances and resources. End users of the IRADES report are the radiation protection authorities. (au)

  15. On the use of age-specific effective dose coefficients in radiation protection of the public

    International Nuclear Information System (INIS)

    Kocher, D.C.; Eckerman, K.F.

    1998-01-01

    Current radiation protection standards for the public include a limit on effective dose in any year for individuals in critical groups. This paper considers the question of how the annual dose limit should be applied in controlling routine exposures of populations consisting of individuals of all ages. We assume that the fundamental objective of radiation protection is limitation of lifetime risk and, therefore, that standards for controlling routine exposures of the public should provide a reasonable correspondence with lifetime risk, taking into account the age dependence of intakes and doses and the variety of radionuclides and exposure pathways of concern. Using new calculations of the per capita (population-averaged) risk of cancer mortality per unit activity inhaled or ingested in the U.S. Environmental Protection Agency's Federal Guidance Report No. 13, we show that applying a limit on annual effective dose only to adults, which was the usual practice in radiation protection of the public before the development of age-specific effective dose coefficients, provides a considerably better correspondence with lifetime risk that applying the annual dose limit to the critical group of any age. (author)

  16. Conversion coefficients for determination of dispersed photon dose during radiotherapy: NRUrad input code for MCNP.

    Science.gov (United States)

    Shahmohammadi Beni, Mehrdad; Ng, C Y P; Krstic, D; Nikezic, D; Yu, K N

    2017-01-01

    Radiotherapy is a common cancer treatment module, where a certain amount of dose will be delivered to the targeted organ. This is achieved usually by photons generated by linear accelerator units. However, radiation scattering within the patient's body and the surrounding environment will lead to dose dispersion to healthy tissues which are not targets of the primary radiation. Determination of the dispersed dose would be important for assessing the risk and biological consequences in different organs or tissues. In the present work, the concept of conversion coefficient (F) of the dispersed dose was developed, in which F = (Dd/Dt), where Dd was the dispersed dose in a non-targeted tissue and Dt is the absorbed dose in the targeted tissue. To quantify Dd and Dt, a comprehensive model was developed using the Monte Carlo N-Particle (MCNP) package to simulate the linear accelerator head, the human phantom, the treatment couch and the radiotherapy treatment room. The present work also demonstrated the feasibility and power of parallel computing through the use of the Message Passing Interface (MPI) version of MCNP5.

  17. On the use of age-specific effective dose coefficients in radiation protection of the public

    International Nuclear Information System (INIS)

    Kocher, D.C.; Eckerman, K.F.

    1998-01-01

    Current radiation protection standards for the public include a limit on effective dose in any year for individuals in critical groups. This paper considers the question of how the annual dose limit should be applied in controlling routine exposures of populations consisting of individuals of all ages. The authors assume that the fundamental objective of radiation protection is limitation of lifetime risk and, therefore, that standards for controlling routine exposures of the public should provide a reasonable correspondence with lifetime risk, taking into account the age dependence of intakes and doses and the variety of radionuclides and exposure pathways of concern. Using new calculations of the per capita (population-averaged) risk of cancer mortality per unit activity inhaled or ingested in the US Environmental Protection Agency's Federal Guidance Report No. 13, the authors show that applying a limit on annual effective dose only to adults, which was the usual practice in radiation protection of the public before the development of age-specific effective dose coefficients, provides a considerably better correspondence with lifetime risk than applying the annual dose limit to the critical group of any age

  18. Normalized glandular dose (DgN) coefficients for flat-panel CT breast imaging

    International Nuclear Information System (INIS)

    Thacker, Samta C; Glick, Stephen J

    2004-01-01

    The development of new digital mammography techniques such as dual-energy imaging, tomosynthesis and CT breast imaging will require investigation of optimal camera design parameters and optimal imaging acquisition parameters. In optimizing these acquisition protocols and imaging systems it is important to have knowledge of the radiation dose to the breast. This study presents a methodology for estimating the normalized glandular dose to the uncompressed breast using the geometry proposed for flat-panel CT breast imaging. The simulation uses the GEANT 3 Monte Carlo code to model x-ray transport and absorption within the breast phantom. The Monte Carlo software was validated for breast dosimetry by comparing results of the normalized glandular dose (DgN) values of the compressed breast to those reported in the literature. The normalized glandular dose was then estimated for a range of breast diameters from 10 cm to 18 cm using an uncompressed breast model with a homogeneous composition of adipose and glandular tissue, and for monoenergetic x-rays from 10 keV to 120 keV. These data were fit providing expressions for the normalized glandular dose. Using these expressions for the DgN coefficients and input variables such as the diameter, height and composition of the breast phantom, the mean glandular dose for any spectra can be estimated. A computer program to provide normalized glandular dose values has been made available online. In addition, figures displaying energy deposition maps are presented to better understand the spatial distribution of dose in CT breast imaging

  19. Effect of the refraction factor of a plastic fiber shell on the internal reflection coefficient

    International Nuclear Information System (INIS)

    Pkrksypkin, A.I.; Ponomarev, L.I.

    1992-01-01

    Results of pilot studies of the effect of refraction factor of plastic fiber shell on the coefficient of light internal reflection in the fiber are presented. It is pointed, that the shell does not absorb the light, but effects the surface layer of the fiber centre so, that dependence of the coefficient of internal reflection on refraction factor of the shell may be described using Fresnel formulae. It is shown, that coefficient of internal reflection decreases with the increase of refraction factor. Technique to determine volume length of scintillation light absorption in the fiber is suggested

  20. Daily radionuclide ingestion and internal radiation doses in Aomori prefecture, Japan.

    Science.gov (United States)

    Ohtsuka, Yoshihito; Kakiuchi, Hideki; Akata, Naofumi; Takaku, Yuichi; Hisamatsu, Shun'ichi

    2013-10-01

    To assess internal annual dose in the general public in Aomori Prefecture, Japan, 80 duplicate cooked diet samples, equivalent to the food consumed over a 400-d period by one person, were collected from 100 volunteers in Aomori City and the village of Rokkasho during 2006–2010 and were analyzed for 11 radionuclides. To obtain average rates of ingestion of radionuclides, the volunteers were selected from among office, fisheries, agricultural, and livestock farm workers. Committed effective doses from ingestion of the diet over a 1-y period were calculated from the analytical results and from International Commission on Radiological Protection dose coefficients; for 40K, an internal effective dose rate from the literature was used. Fisheries workers had significantly higher combined internal annual dose than the other workers, possibly because of high rates of ingestion of marine products known to have high 210Po concentrations. The average internal dose rate, weighted by the numbers of households in each worker group in Aomori Prefecture, was estimated at 0.47 mSv y-1. Polonium-210 contributed 49% of this value. The sum of committed effective dose rates for 210Po, 210Pb, 228Ra, and 14C and the effective dose rate of 40K accounted for approximately 99% of the average internal dose rate.

  1. Fluence to Dose Equivalent Conversion Coefficients for Evaluation of Accelerator Radiation Environments

    International Nuclear Information System (INIS)

    Thomas, Ralph H.; Zeman, Gary H.

    2001-01-01

    The derivation of a set of conversion functions for the expression of neutron fluence measurements in terms of Effective Dose, E, is described. Four functions in analytical form are presented, covering the neutron energy range from 2.5 10-8 to 10+4 MeV, for the interpretation of fluence measurements in the typical irradiation conditions experienced around high-energy proton accelerators such as the Bevatron. For neutron energies below 200 MeV the analytical functions were modeled after the ISO and ROT conversion coefficients in ICRU 57. For neutron energies above 200 MeV, the analytical function was derived from an analysis of recent published data. Sample calculations using either the analytical expressions or the tabulated conversion coefficients from which the analytical expressions are derived show agreement to better than plus/minus 5%

  2. Organ-specific external dose coefficients and protective apron transmission factors for historical dose reconstruction for medical personnel.

    Science.gov (United States)

    Simon, Steven L

    2011-07-01

    While radiation absorbed dose (Gy) to the skin or other organs is sometimes estimated for patients from diagnostic radiologic examinations or therapeutic procedures, rarely is occupationally-received radiation absorbed dose to individual organs/tissues estimated for medical personnel; e.g., radiologic technologists or radiologists. Generally, for medical personnel, equivalent or effective radiation doses are estimated for compliance purposes. In the very few cases when organ doses to medical personnel are reconstructed, the data is usually for the purpose of epidemiologic studies; e.g., a study of historical doses and risks to a cohort of about 110,000 radiologic technologists presently underway at the U.S. National Cancer Institute. While ICRP and ICRU have published organ-specific external dose conversion coefficients (DCCs) (i.e., absorbed dose to organs and tissues per unit air kerma and dose equivalent per unit air kerma), those factors have been published primarily for mono-energetic photons at selected energies. This presents two related problems for historical dose reconstruction, both of which are addressed here. It is necessary to derive conversion factor values for (1) continuous distributions of energy typical of diagnostic medical x-rays (bremsstrahlung radiation), and (2) energies of particular radioisotopes used in medical procedures, neither of which are presented in published tables. For derivation of DCCs for bremsstrahlung radiation, combinations of x-ray tube potentials and filtrations were derived for different time periods based on a review of relevant literature. Three peak tube potentials (70 kV, 80 kV, and 90 kV) with four different amounts of beam filtration were determined to be applicable for historic dose reconstruction. The probabilities of these machine settings were assigned to each of the four time periods (earlier than 1949, 1949-1954, 1955-1968, and after 1968). Continuous functions were fit to each set of discrete values of the

  3. Reduced Variance using ADVANTG in Monte Carlo Calculations of Dose Coefficients to Stylized Phantoms

    Science.gov (United States)

    Hiller, Mauritius; Bellamy, Michael; Eckerman, Keith; Hertel, Nolan

    2017-09-01

    The estimation of dose coefficients of external radiation sources to the organs in phantoms becomes increasingly difficult for lower photon source energies. This study focus on the estimation of photon emitters around the phantom. The computer time needed to calculate a result within a certain precision can be lowered by several orders of magnitude using ADVANTG compared to a standard run. Using ADVANTG which employs the DENOVO adjoint calculation package enables the user to create a fully populated set of weight windows and source biasing instructions for an MCNP calculation.

  4. Background internal dose rates of earthworm and arthropod species in the forests of Aomori, Japan

    International Nuclear Information System (INIS)

    Ohtsuka, Yoshihito; Takaku, Yuichi; Hisamatsu, Shun'ichi

    2013-01-01

    We measured naturally occurring radionuclides in samples from an earthworm species and 11 arthropod species collected in coniferous forests in Rokkasho, Aomori, Japan, to assess background internal radiation dose rates. The rates were calculated from the measured concentrations of the radionuclides and dose coefficients from the literature. The mean internal dose rate of composite earthworm samples was 0.35 μGy h -1 , whereas the mean dose rates of the arthropod samples ranged from 36 nGy h -1 to 0.79 μGy h -1 . Polonium-210 was the radionuclide with the highest contribution to the internal dose rate for all the species, except the longhorn beetle. (author)

  5. Uncertainty of inhalation dose coefficients for representative physical and chemical forms of iodine-131

    Science.gov (United States)

    Harvey, Richard Paul, III

    Releases of radioactive material have occurred at various Department of Energy (DOE) weapons facilities and facilities associated with the nuclear fuel cycle in the generation of electricity. Many different radionuclides have been released to the environment with resulting exposure of the population to these various sources of radioactivity. Radioiodine has been released from a number of these facilities and is a potential public health concern due to its physical and biological characteristics. Iodine exists as various isotopes, but our focus is on 131I due to its relatively long half-life, its prevalence in atmospheric releases and its contribution to offsite dose. The assumption of physical and chemical form is speculated to have a profound impact on the deposition of radioactive material within the respiratory tract. In the case of iodine, it has been shown that more than one type of physical and chemical form may be released to, or exist in, the environment; iodine can exist as a particle or as a gas. The gaseous species can be further segregated based on chemical form: elemental, inorganic, and organic iodides. Chemical compounds in each class are assumed to behave similarly with respect to biochemistry. Studies at Oak Ridge National Laboratories have demonstrated that 131I is released as a particulate, as well as in elemental, inorganic and organic chemical form. The internal dose estimate from 131I may be very different depending on the effect that chemical form has on fractional deposition, gas uptake, and clearance in the respiratory tract. There are many sources of uncertainty in the estimation of environmental dose including source term, airborne transport of radionuclides, and internal dosimetry. Knowledge of uncertainty in internal dosimetry is essential for estimating dose to members of the public and for determining total uncertainty in dose estimation. Important calculational steps in any lung model is regional estimation of deposition fractions

  6. Estimation of internal dose from radiocesium and phantom

    International Nuclear Information System (INIS)

    Uchiyama, Masafumi; Nakamura, Yuji

    1994-01-01

    A complicated model describing the movement of a radionuclide in both the natural environment and socioeconomical systems is usually used to estimate the internal dose to the public in terms of collective dose, taking demographic data into account. The result can be certified for reliability in some compartments of the model. One of the compartments is the body content. In the case of radiocesium, the individual body burden can be measured using a whole-body counter. The measurement must be calibrated with a phantom. The public is composed of individuals of various ages. Accordingly, the whole-body counter should be calibrated with a set of phantoms approximating individuals of different body sizes. Relationships between counting efficiency and body size were analyzed on 137 Cs 134 Cs or 40 K incorporated into the whole-body using a set of phantoms. Four sizes covering average Japanese physiques from infant to adult male, were chosen to prepare an anthropomorphic phantom system. The distribution of 137 Cs in aquatic solution was homogeneous through the phantom. A whole-body counter at the National Institute of Radiological Sciences, was used at a rate of 5 cm per minute in a scanning mode. The measurements were carried out in an iron room. Relations were analyzed between counting efficiency and some anthropometric parameters. The best fit was given by a linear equation of both reciprocals of height in cm and weight in kg, with a correlation coefficient of 1.00 for 137 Cs. The result indicates that radioactivity of 137 Cs can be determined for individuals with different anthropometric parameters using the whole-body counter system. This means that effective equivalent doses for individuals can be computed accurately from the measurements. Further, an estimate on the body content from an dose estimation model using measurements of radioactivity in environmental substances can be evaluated by comparing the body burden measured. (J.P.N.)

  7. Ingestion of Nevada Test Site Fallout: Internal dose estimates

    International Nuclear Information System (INIS)

    Whicker, F.W.; Kirchner, T.B.; Anspaugh, L.R.

    1996-01-01

    This paper summarizes individual and collective dose estimates for the internal organs of hypothetical yet representative residents of selected communities that received measurable fallout from nuclear detonations at the Nevada Test Site. The doses, which resulted from ingestion of local and regional food products contaminated with over 20 radionuclides, were estimated with use of the PATHWAY food-chain-transport model to provide estimates of central tendency and uncertainty. The thyroid gland received much higher doses than other internal organs and tissues. In a avery few cases, infants might have received thyroid doses in excess of 1 Gy, depending on location, diet, and timing of fallout. 131 I was the primary thyroid dose contributor, and fresh milk was the main exposure pathway. With the exception of the thyroid, organ doses from the ingestion pathway were much smaller (<3%) than those from external gamma exposure to deposited fallout. Doses to residents living closest to the Nevada Test Site were contributed mainly by a few fallout events; doses to more distantly located people were generally smaller, but a greater number of events provided measurable contributions. The effectiveness of different fallout events in producing internal organ doses through ingestion varied dramatically with seasonal timing of the test, with maximum dose per unit fallout occurring for early summer depositions when milk cows were on pasture and fresh, local vegetables were used. Within specific communities, internal doses differed by age, sex, and lifestyle. Collective internal dose estimates for specific geographic areas are provided

  8. Development of internal dose calculation model and the data base updated IDES (Internal Dose Estimation System)

    International Nuclear Information System (INIS)

    Hongo, Shozo; Yamaguchi, Hiroshi; Takeshita, Hiroshi; Iwai, Satoshi.

    1994-01-01

    A computer program named IDES is developed by BASIC language for a personal computer and translated to C language of engineering work station. The IDES carries out internal dose calculations described in ICRP Publication 30 and it installs the program of transformation method which is an empirical method to estimate absorbed fractions of different physiques from ICRP Referenceman. The program consists of three tasks: productions of SAF for Japanese including children, productions of SEE, Specific Effective Energy, and calculation of effective dose equivalents. Each task and corresponding data file appear as a module so as to meet future requirement for revisions of the related data. Usefulness of IDES is discussed by exemplifying the case that 5 age groups of Japanese intake orally Co-60 or Mn-54. (author)

  9. Age-dependent doses to members of the public from intake of radionuclides: Pt. 5. Compilation of ingestion and inhalation dose coefficients

    International Nuclear Information System (INIS)

    1996-01-01

    The present report is a compilation of age-dependent committed effective dose coefficients for ingestion and inhalation of radionuclides of the 31 elements covered in previous CRP Publications. The biokinetic models for adults given in ICRP Publication 30 are applied to calculate these dose coefficients, except that age-specific excretion rates are used and increased gastrointestinal absorption in infants is assurred. Changes in body mass, and tissue geometry in children are also taken into account. (UK)

  10. Theoretical expression of the internal conversion coefficient of a M1 transition between two atomic states

    International Nuclear Information System (INIS)

    Attallah, F.; Chemin, J.F.; Scheurer, J.N.; Karpeshin, F.; Harston, M.

    1997-01-01

    We have established a general relation for the expression of the internal conversion of an M 1 transition a 1s electronic state to an empty ns electronic bound state. Under the hypothesis that the density of the electron level ρ n satisfies the condition ρ n Γ >> 1 (where Γ is the total width of the excited atomic state) a calculation in the first order gives a relation for the internal conversion coefficient.This relation shows that the internal conversion coefficient takes a resonant character when the nuclear energy transition is smaller than the binding energy of the 1s electron. An application of this relation to an M 1 transition in the case of the ion 125 T e with a charge state Q = 45 and an 1s electron binding energy E B 45 = 35.581 KeV gives the value for the internal conversion coefficient R = 5.7

  11. Dose conversion coefficients for neutron exposure to the lens of the human eye

    International Nuclear Information System (INIS)

    Manger, Ryan P.; Bellamy, Michael B.; Eckerman, Keith F.

    2011-01-01

    Dose conversion coefficients for the lens of the human eye have been calculated for neutron exposure at energies from 1 x 10 -9 to 20 MeV and several standard orientations: anterior-to-posterior, rotational and right lateral. MCNPX version 2.6.0, a Monte Carlo-based particle transport package, was used to determine the energy deposited in the lens of the eye. The human eyeball model was updated by partitioning the lens into sensitive and insensitive volumes as the anterior portion (sensitive volume) of the lens being more radiosensitive and prone to cataract formation. The updated eye model was used with the adult UF-ORNL mathematical phantom in the MCNPX transport calculations.

  12. Dose conversion coefficients for neutron exposure to the lens of the human eye

    International Nuclear Information System (INIS)

    Manger, R. P.; Bellamy, M. B.; Eckerman, K. F.

    2012-01-01

    Dose conversion coefficients for the lens of the human eye have been calculated for neutron exposure at energies from 1 x 10 -9 to 20 MeV and several standard orientations: anterior-to-posterior, rotational and right lateral. MCNPX version 2.6.0, a Monte Carlo-based particle transport package, was used to determine the energy deposited in the lens of the eye. The human eyeball model was updated by partitioning the lens into sensitive and insensitive volumes as the anterior portion (sensitive volume) of the lens being more radiosensitive and prone to cataract formation. The updated eye model was used with the adult UF-ORNL mathematical phantom in the MCNPX transport calculations. (authors)

  13. Internal radiation dose in diagnostic nuclear medicine

    Energy Technology Data Exchange (ETDEWEB)

    Roedler, H D; Kaul, A; Hine, G J

    1978-01-01

    Absorbed dose values per unit administered activity for the most frequently used radipharmaceuticals and methods were calculated according to the MIRD concept or compiled from literature and were tabulated in conventional as well as in the SI-units recently introduced. The data are given for critical or investigated organs, ovaries, testes and red bone marrow. Where available, dose values for newborns, infants and children are included. Additionally, mean values of administered activity are listed. The manner in which to estimate the radiation dose to the patient is to multiply the tabulated dose values per unit administered activity with the corresponding mean or the actually administered activity. The methods are arranged in correlation with the following nuclear medical subspecialities: 1. Endocrinology 2. Neurology, 3. Osteomyology, 4. Gastroenterology, 5. Nephrology, 6. Pulmonology, 7. Hematology, 8. Cardiology/Angiology.

  14. Noninvasive photoacoustic measurement of absorption coefficient using internal light irradiation of cylindrical diffusing fiber

    Science.gov (United States)

    Peng, Dong-qing; Zhu, Li-li; Li, Zhi-fang; Li, Hui

    2017-09-01

    Absorption coefficient of biological tissue is an important parameter in biomedicine, but its determination remains a challenge. In this paper, we propose a method using focusing photoacoustic imaging technique and internal light irradiation of cylindrical diffusing fiber (CDF) to quantify the target optical absorption coefficient. Absorption coefficients for ink absorbers are firstly determined through photoacoustic and spectrophotometric measurements at the same excitation, which demonstrates the feasibility of this method. Also, the optical absorption coefficients of ink absorbers with several concentrations are measured. Finally, the two-dimensional scanning photoacoustic image is obtained. Optical absorption coefficient measurement and simultaneous photoacoustic imaging of absorber non-invasively are the typical characteristics of the method. This method can play a significant role for non-invasive determination of blood oxygen saturation, the absorption-based imaging and therapy.

  15. Systematic errors in the tables of theoretical total internal conversion coefficients

    International Nuclear Information System (INIS)

    Dragoun, O.; Rysavy, M.

    1992-01-01

    Some of the total internal conversion coefficients presented in widely used tables of Rosel et al (1978 Atom. Data Nucl. Data Tables 21, 291) were found to be erroneous. The errors appear for some low transition energies, all multipolarities, and probably for all elements. The origin of the errors is explained. The subshell conversion coefficients of Rosel et al, where available, agree with our calculations. to within a few percent. (author)

  16. Human data and internal dose assessment

    International Nuclear Information System (INIS)

    Kawamura, H.; Tanaka, G.; Shiraishi, K.; Yamamoto, M.

    1992-01-01

    Recent data on physical and anatomical and physiological or metabolic data regarding Japanese Reference Man is briefly reviewed. This includes reference values for masses of all organs and tissues proposed for a Japanese Reference male adult. Part of the data is used to assess alpha doses to bone tissues from naturally occurring 226 Ra in bone of Japanese adult. (author)

  17. Evaluation of the fluence to dose conversion coefficients for high energy neutrons using a voxel phantom coupled with the GEANT4 code

    CERN Document Server

    Paganini, S

    2005-01-01

    Crews working on present-day jet aircraft are a large occupationally exposed group with a relatively high average effective dose from Galactic cosmic radiation. Crews of future high-speed commercial flying at higher altitudes would be even more exposed. To help reduce the significant uncertainties in calculations of such exposures, the male adult voxels phantom MAX, developed in the Nuclear Energy Department of Pernambuco Federal University in Brazil, has been coupled with the Monte Carlo simulation code GEANT4. This toolkit, distributed and upgraded from the international scientific community of CERN/Switzerland, simulates thermal to ultrahigh energy neutrons transport and interactions in the matter. The high energy neutrons are pointed as the component that contribute about 70% of the neutron effective dose that represent the 35% to 60% total dose at aircraft altitude. In this research calculations of conversion coefficients from fluence to effective dose are performed for neutrons of energies from 100 MeV ...

  18. An Internal Dose Assessment Associated with Personal Food Intake

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Joeun; Jae, Moosung [Hanyang University, Seoul (Korea, Republic of); Hwang, Wontae [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    ICRP (International Commission on Radiological Protection), Therefore, had recommended the concept of 'Critical Group'. Recently the ICRP has recommended the use of 'Representative Person' on the new basic recommendation 103. On the other hand the U.S. NRC (Nuclear Regulatory Commission) has adopted more conservative concept, 'Maximum Exposed Individuals (MEI)' of critical Group. The dose assessment in Korea is based on MEI. Although dose assessment based on MEI is easy to receive the permission of the regulatory authority, it is not efficient. Meanwhile, the internal dose by food consumption takes an important part. Therefore, in this study, the internal dose assessment was performed in accordance with ICRP's new recommendations. The internal dose assessment was performed in accordance with ICRP's new recommendations. It showed 13.2% decreased of the annual internal dose due to gaseous effluents by replacing MEI to the concept of representative person. Also, this calculation based on new ICRP's recommendation has to be extended to all areas of individual dose assessment. Then, more accurate and efficient values might be obtained for dose assessment.

  19. Organ dose conversion coefficients based on a voxel mouse model and MCNP code for external photon irradiation.

    Science.gov (United States)

    Zhang, Xiaomin; Xie, Xiangdong; Cheng, Jie; Ning, Jing; Yuan, Yong; Pan, Jie; Yang, Guoshan

    2012-01-01

    A set of conversion coefficients from kerma free-in-air to the organ absorbed dose for external photon beams from 10 keV to 10 MeV are presented based on a newly developed voxel mouse model, for the purpose of radiation effect evaluation. The voxel mouse model was developed from colour images of successive cryosections of a normal nude male mouse, in which 14 organs or tissues were segmented manually and filled with different colours, while each colour was tagged by a specific ID number for implementation of mouse model in Monte Carlo N-particle code (MCNP). Monte Carlo simulation with MCNP was carried out to obtain organ dose conversion coefficients for 22 external monoenergetic photon beams between 10 keV and 10 MeV under five different irradiation geometries conditions (left lateral, right lateral, dorsal-ventral, ventral-dorsal, and isotropic). Organ dose conversion coefficients were presented in tables and compared with the published data based on a rat model to investigate the effect of body size and weight on the organ dose. The calculated and comparison results show that the organ dose conversion coefficients varying the photon energy exhibits similar trend for most organs except for the bone and skin, and the organ dose is sensitive to body size and weight at a photon energy approximately <0.1 MeV.

  20. Research on friction coefficient of nuclear Reactor Vessel Internals Hold Down Spring: Stress coefficient test analysis method

    International Nuclear Information System (INIS)

    Linjun, Xie; Guohong, Xue; Ming, Zhang

    2016-01-01

    Graphical abstract: HDS stress coefficient test apparatus. - Highlights: • This paper performs mathematic deduction to the physical model of Hold Down Spring (HDS), establishes a mathematic model of axial load P and stress, stress coefficient and friction coefficient and designs a set of test apparatuses for simulating the pretightening process of the HDS for the first time according to a model similarity criterion. • The mathematical relation between the load and the strain is obtained about the HDS, and the mathematical model of the stress coefficient and the friction coefficient is established. So, a set of test apparatuses for obtaining the stress coefficient is designed according to the model scaling criterion and the friction coefficient of the K1000 HDS is calculated to be 0.336 through the obtained stress coefficient. • The relation curve between the theoretical load and the friction coefficient is obtained through analysis and indicates that the change of the friction coefficient f would influence the pretightening load under the condition of designed stress. The necessary pretightening load in the design process is calculated to be 5469 kN according to the obtained friction coefficient. Therefore, the friction coefficient and the pretightening load under the design conditions can provide accurate pretightening data for the analysis and design of the reactor HDS according to the operations. - Abstract: This paper performs mathematic deduction to the physical model of Hold Down Spring (HDS), establishes a mathematic model of axial load P and stress, stress coefficient and friction coefficient and designs a set of test apparatuses for simulating the pretightening process of the HDS for the first time according to a model similarity criterion. By carrying out tests and researches through a stress testing technique, P–σ curves in loading and unloading processes of the HDS are obtained and the stress coefficient k f of the HDS is obtained. So, the

  1. Research on friction coefficient of nuclear Reactor Vessel Internals Hold Down Spring: Stress coefficient test analysis method

    Energy Technology Data Exchange (ETDEWEB)

    Linjun, Xie, E-mail: linjunx@zjut.edu.cn [College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou 310014 (China); Guohong, Xue; Ming, Zhang [Shanghai Nuclear Engineering Research & Design Institute, Shanghai 200233 (China)

    2016-08-01

    Graphical abstract: HDS stress coefficient test apparatus. - Highlights: • This paper performs mathematic deduction to the physical model of Hold Down Spring (HDS), establishes a mathematic model of axial load P and stress, stress coefficient and friction coefficient and designs a set of test apparatuses for simulating the pretightening process of the HDS for the first time according to a model similarity criterion. • The mathematical relation between the load and the strain is obtained about the HDS, and the mathematical model of the stress coefficient and the friction coefficient is established. So, a set of test apparatuses for obtaining the stress coefficient is designed according to the model scaling criterion and the friction coefficient of the K1000 HDS is calculated to be 0.336 through the obtained stress coefficient. • The relation curve between the theoretical load and the friction coefficient is obtained through analysis and indicates that the change of the friction coefficient f would influence the pretightening load under the condition of designed stress. The necessary pretightening load in the design process is calculated to be 5469 kN according to the obtained friction coefficient. Therefore, the friction coefficient and the pretightening load under the design conditions can provide accurate pretightening data for the analysis and design of the reactor HDS according to the operations. - Abstract: This paper performs mathematic deduction to the physical model of Hold Down Spring (HDS), establishes a mathematic model of axial load P and stress, stress coefficient and friction coefficient and designs a set of test apparatuses for simulating the pretightening process of the HDS for the first time according to a model similarity criterion. By carrying out tests and researches through a stress testing technique, P–σ curves in loading and unloading processes of the HDS are obtained and the stress coefficient k{sub f} of the HDS is obtained. So, the

  2. Controlling the Internal Heat Transfer Coefficient by the Characteristics of External Flows

    Science.gov (United States)

    Zhuromskii, V. M.

    2018-01-01

    The engineering-physical fundamentals of substance synthesis in a boiling apparatus are presented. We have modeled a system of automatic stabilization of the maximum internal heat transfer coefficient in such an apparatus by the characteristics of external flows on the basis of adaptive seeking algorithms. The results of operation of the system in the shop are presented.

  3. Internal doses in Oak Ridge. The Internet beams

    International Nuclear Information System (INIS)

    Passchier, W.F.

    1997-01-01

    A brief overview is given of the information, presented by the Radiation Internal Dose Information Center (RIDIC) of the Oak Ridge Associated Universities in Oak Ridge, TN, USA, via Internet (www.orau.gov/ehsd/ridic.htm)

  4. Dose conversion coefficients for monoenergetic electrons incident on a realistic human eye model with different lens cell populations.

    Science.gov (United States)

    Nogueira, P; Zankl, M; Schlattl, H; Vaz, P

    2011-11-07

    The radiation-induced posterior subcapsular cataract has long been generally accepted to be a deterministic effect that does not occur at doses below a threshold of at least 2 Gy. Recent epidemiological studies indicate that the threshold for cataract induction may be much lower or that there may be no threshold at all. A thorough study of this subject requires more accurate dose estimates for the eye lens than those available in ICRP Publication 74. Eye lens absorbed dose per unit fluence conversion coefficients for electron irradiation were calculated using a geometrical model of the eye that takes into account different cell populations of the lens epithelium, together with the MCNPX Monte Carlo radiation transport code package. For the cell population most sensitive to ionizing radiation-the germinative cells-absorbed dose per unit fluence conversion coefficients were determined that are up to a factor of 4.8 higher than the mean eye lens absorbed dose conversion coefficients for electron energies below 2 MeV. Comparison of the results with previously published values for a slightly different eye model showed generally good agreement for all electron energies. Finally, the influence of individual anatomical variability was quantified by positioning the lens at various depths below the cornea. A depth difference of 2 mm between the shallowest and the deepest location of the germinative zone can lead to a difference between the resulting absorbed doses of up to nearly a factor of 5000 for electron energy of 0.7 MeV.

  5. Dose conversion coefficients for monoenergetic electrons incident on a realistic human eye model with different lens cell populations

    International Nuclear Information System (INIS)

    Nogueira, P; Vaz, P; Zankl, M; Schlattl, H

    2011-01-01

    The radiation-induced posterior subcapsular cataract has long been generally accepted to be a deterministic effect that does not occur at doses below a threshold of at least 2 Gy. Recent epidemiological studies indicate that the threshold for cataract induction may be much lower or that there may be no threshold at all. A thorough study of this subject requires more accurate dose estimates for the eye lens than those available in ICRP Publication 74. Eye lens absorbed dose per unit fluence conversion coefficients for electron irradiation were calculated using a geometrical model of the eye that takes into account different cell populations of the lens epithelium, together with the MCNPX Monte Carlo radiation transport code package. For the cell population most sensitive to ionizing radiation-the germinative cells-absorbed dose per unit fluence conversion coefficients were determined that are up to a factor of 4.8 higher than the mean eye lens absorbed dose conversion coefficients for electron energies below 2 MeV. Comparison of the results with previously published values for a slightly different eye model showed generally good agreement for all electron energies. Finally, the influence of individual anatomical variability was quantified by positioning the lens at various depths below the cornea. A depth difference of 2 mm between the shallowest and the deepest location of the germinative zone can lead to a difference between the resulting absorbed doses of up to nearly a factor of 5000 for electron energy of 0.7 MeV.

  6. Calculation of the dose caused by internal radiation

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    For the purposes of monitoring radiation exposure it is necessary to determine or to estimate the dose caused by both external and internal radiation. When comparing the value of exposure to the dose limits, account must be taken of the total dose incurred from different sources. This guide explains how to calculate the committed effective dose caused by internal radiation and gives the conversion factors required for the calculation. Application of the maximum values for radiation exposure is dealt with in ST guide 7.2, which also sets out the definitions of the quantities and concepts most commonly used in the monitoring of radiation exposure. The monitoring of exposure and recording of doses are dealt with in ST Guides 7.1 and 7.4.

  7. An international intercomparison of absorbed dose measurements for radiation therapy

    International Nuclear Information System (INIS)

    Taiman Kadni; Noriah Mod Ali

    2002-01-01

    Dose intercomparison on an international basis has become an important component of quality assurance measurement i.e. to check the performance of absorbed dose measurements in radiation therapy. The absorbed dose to water measurements for radiation therapy at the SSDL, MINT have been regularly compared through international intercomparison programmes organised by the IAEA Dosimetry Laboratory, Seibersdorf, Austria such as IAEA/WHO TLD postal dose quality audits and the Intercomparison of therapy level ionisation chamber calibration factors in terms of air kerma and absorbed dose to water calibration factors. The results of these intercomparison in terms of percentage deviations for Cobalt 60 gamma radiation and megavoltage x-ray from medical linear accelerators participated by the SSDL-MINT during the year 1985-2001 are within the acceptance limit. (Author)

  8. Define of internal recirculation coefficient for biological wastewater treatment in anoxic and aerobic bioreactors

    Science.gov (United States)

    Rossinskyi, Volodymyr

    2018-02-01

    The biological wastewater treatment technologies in anoxic and aerobic bioreactors with recycle of sludge mixture are used for the effective removal of organic compounds from wastewater. The change rate of sludge mixture recirculation between bioreactors leads to a change and redistribution of concentrations of organic compounds in sludge mixture in bioreactors and change hydrodynamic regimes in bioreactors. Determination of the coefficient of internal recirculation of sludge mixture between bioreactors is important for the choice of technological parameters of biological treatment (wastewater treatment duration in anoxic and aerobic bioreactors, flow capacity of recirculation pumps). Determination of the coefficient of internal recirculation of sludge mixture requires integrated consideration of hydrodynamic parameter (flow rate), kinetic parameter (rate of oxidation of organic compounds) and physical-chemical parameter of wastewater (concentration of organic compounds). The conducted numerical experiment from the proposed mathematical equations allowed to obtain analytical dependences of the coefficient of internal recirculation sludge mixture between bioreactors on the concentration of organic compounds in wastewater, the duration of wastewater treatment in bioreactors.

  9. Proton and photon absorbed-dose conversion coefficients for embryo and foetus from top-down irradiation geometry

    International Nuclear Information System (INIS)

    Chen, J.

    2007-01-01

    Absorbed-dose conversion coefficients are calculated for the embryo of 8 weeks and the foetus of 3, 6 or 9 months when the mother's body is exposed to protons and photons from top-down (TOP) direction. It provides data sets in addition to other standard irradiation geometries published previously. The TOP-irradiation geometry is considered here, because high-energy particles are often peaked from the TOP direction onboard aircraft. The results show that absorbed-doses from high-energy particles could be underestimated significantly if isotropic (ISO) irradiation geometry is assumed. For protons of 100 GeV, absorbed-doses from TOP irradiation are ∼2.3-2.9 times higher than the doses from ISO irradiation for different foetal ages. For 10 GeV photons, foetal doses from TOP irradiation are ∼6.8-12 times higher than the doses from ISO irradiation. The coefficients from TOP-irradiation geometry are given in wide energy ranges, from 100 MeV to 100 GeV for protons and from 50 V to 10 GeV for photons. They can, therefore, be used in various applications whenever exposure from the TOP-irradiation direction is concerned. (authors)

  10. IAEA/IDEAS intercomparison exercise on internal dose assessment

    International Nuclear Information System (INIS)

    Doerfel, H.; Andrasi, A.; Cruz-Suarez, R.; Castellani, C. M.; Hurtgen, C.; Marsh, J.; Zeger, J.

    2007-01-01

    An Internet based intercomparison exercise on assessment of occupational exposure due to intakes of radionuclides has been performed to check the applicability of the 'General Guidelines for the Assessment of Internal Dose from Monitoring Data' developed by the IDEAS group. There were six intake cases presented on the Internet and 81 participants worldwide reported solutions to these cases. Results of the exercise indicate that the guidelines have a positive influence on the methodologies applied for dose assessments and, if correctly applied, improve the harmonisation of assessed doses. (authors)

  11. Internal dose estimation by bio-assay techniques

    International Nuclear Information System (INIS)

    Sawant, Pramilla D.

    2016-01-01

    Radiation exposure, both external and internal, can occur to radiation workers during the operation of various nuclear fuel cycle facilities and radiation facilities. The assessment of radiation doses to workers, routinely or potentially exposed to radiation, through intake of radionuclide is an integral part of the radiation protection programme. Internal dose is the radiation exposure that results from the intake of radioactive materials into the body by inhalation, ingestion, absorption through the skin or via wounds. Assessment of radiation doses arising from the intake of radioactive material by the workers is termed as internal exposure assessment. Unlike external exposure, internal exposure cannot be measured directly. Its evaluation is based on the calculation of the intake of radionuclide either from direct measurements (e.g, external monitoring of whole body or of specific organs and tissues) or indirect measurements (e.g. radioactivity in urine, faeces, breath or samples from the working environment) (ICRP Pub. 78, 1997 and NRPB-W60, 2004). Another method of internal dose assessment is based on the measurement of airborne radionuclides in the working areas of the facility and the worker's occupancy in those areas

  12. JADA: a graphical user interface for comprehensive internal dose assessment in nuclear medicine.

    Science.gov (United States)

    Grimes, Joshua; Uribe, Carlos; Celler, Anna

    2013-07-01

    The main objective of this work was to design a comprehensive dosimetry package that would keep all aspects of internal dose calculation within the framework of a single software environment and that would be applicable for a variety of dose calculation approaches. Our MATLAB-based graphical user interface (GUI) can be used for processing data obtained using pure planar, pure SPECT, or hybrid planar/SPECT imaging. Time-activity data for source regions are obtained using a set of tools that allow the user to reconstruct SPECT images, load images, coregister a series of planar images, and to perform two-dimensional and three-dimensional image segmentation. Curve fits are applied to the acquired time-activity data to construct time-activity curves, which are then integrated to obtain time-integrated activity coefficients. Subsequently, dose estimates are made using one of three methods. The organ level dose calculation subGUI calculates mean organ doses that are equivalent to dose assessment performed by OLINDA/EXM. Voxelized dose calculation options, which include the voxel S value approach and Monte Carlo simulation using the EGSnrc user code DOSXYZnrc, are available within the process 3D image data subGUI. The developed internal dosimetry software package provides an assortment of tools for every step in the dose calculation process, eliminating the need for manual data transfer between programs. This saves times and minimizes user errors, while offering a versatility that can be used to efficiently perform patient-specific internal dose calculations in a variety of clinical situations.

  13. WRAITH, Internal and External Doses from Atmospheric Release of Isotopes

    International Nuclear Information System (INIS)

    1984-01-01

    1 - Description of problem or function: WRAITH calculates the atmospheric transport of radioactive material to each of a number of downwind receptor points and the external and internal doses to a reference man at each of the receptor points. 2 - Method of solution: The movement of the released material through the atmosphere is calculated using a bivariate straight-line Gaussian distribution model with Pasquill values for standard deviations. The quantity of material in the released cloud is modified during its transit time to account for radioactive decay and daughter production. External doses due to exposure to the cloud can be calculated using a semi-infinite cloud approximation or a 'finite plume' three-dimensional point-kernel numerical integration technique. Internal doses due to acute inhalation are calculated using the ICRP Task Group Model and a four-segmented gastro- intestinal tract model. Translocation of the material between body compartments and retention in the body compartments are calculated using multiple exponential retention functions. Internal doses to each organ are calculated as sums of cross-organ doses with each target organ irradiated by radioactive material in a number of source organs. All doses are calculated in rads with separate values determined for high-LET and low-LET radiation. 3 - Restrictions on the complexity of the problem: - Doses to only three target organs (total body, red bone marrow, and the lungs) are considered and acute inhalation is the only pathway for material to enter the body. The dose response model is not valid for high-LET radiation other than alphas. The high-LET calculation ignores the contributions of neutrons, spontaneous fission fragments, and alpha recoil nuclei

  14. Friction coefficient and limiter load test analysis by flexibility coefficient model of Hold-Down Spring of nuclear reactor vessel internals

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Linjun [Zhejiang Univ. of Technology, Hangzhou (China). College of Mechanical Engineering; Xue, Guohong; Zhang, Ming [Shanghai Nuclear Engineering Research and Design Institute, Shanghai (China)

    2017-11-15

    The friction force between the contact surfaces of a reactor internal hold-down spring (HDS) and core barrel flanges can directly influence the axial stiffness of an HDS. However, friction coefficient cannot be obtained through theoretical analysis. This study performs a mathematical deduction of the physical model of an HDS. Moreover, a mathematical model of axial load P, displacement δ, and flexibility coefficient is established, and a set of test apparatuses is designed to simulate the preloading process of the HDS. According to the experimental research and theoretical analysis, P-δ curves and the flexibility coefficient λ are obtained in the loading processes of the HDS. The friction coefficient f of the M1000 HDS is further calculated as 0.224. The displacement limit load value (4,638 kN) can be obtained through a displacement limit experiment. With the friction coefficient considered, the theoretical load is 4,271 kN, which is relatively close to the experimental result. Thus, the friction coefficient exerts an influence on the displacement limit load P. The friction coefficient should be considered in the design analysis for HDS.

  15. Friction coefficient and limiter load test analysis by flexibility coefficient model of Hold-Down Spring of nuclear reactor vessel internals

    International Nuclear Information System (INIS)

    Xie, Linjun

    2017-01-01

    The friction force between the contact surfaces of a reactor internal hold-down spring (HDS) and core barrel flanges can directly influence the axial stiffness of an HDS. However, friction coefficient cannot be obtained through theoretical analysis. This study performs a mathematical deduction of the physical model of an HDS. Moreover, a mathematical model of axial load P, displacement δ, and flexibility coefficient is established, and a set of test apparatuses is designed to simulate the preloading process of the HDS. According to the experimental research and theoretical analysis, P-δ curves and the flexibility coefficient λ are obtained in the loading processes of the HDS. The friction coefficient f of the M1000 HDS is further calculated as 0.224. The displacement limit load value (4,638 kN) can be obtained through a displacement limit experiment. With the friction coefficient considered, the theoretical load is 4,271 kN, which is relatively close to the experimental result. Thus, the friction coefficient exerts an influence on the displacement limit load P. The friction coefficient should be considered in the design analysis for HDS.

  16. Calculating the heat transfer coefficient of frame profiles with internal cavities

    DEFF Research Database (Denmark)

    Noyé, Peter Anders; Laustsen, Jacob Birck; Svendsen, Svend

    2004-01-01

    . The heat transfer coefficient is determined by two-dimensional numerical calculations and by measurements. Calculations are performed in Therm (LBNL (2001)), which is developed at Lawrence Berkeley National Laboratory, USA. The calculations are performed in accordance with the future European standards...... correspondence between measured and calculated values. Hence, when determining the heat transfer coefficient of frame profiles with internal cavities by calculations, it is necessary to apply a more detailed radiation exchange model than described in the prEN ISO 10077-2 standard. The ISO-standard offers......Determining the energy performance of windows requires detailed knowledge of the thermal properties of their different elements. A series of standards and guidelines exist in this area. The thermal properties of the frame can be determined either by detailed two-dimensional numerical methods...

  17. Internal conversion coefficients for atomic numbers Z less than or equal to 30

    International Nuclear Information System (INIS)

    Band, I.M.; Trzhaskovskaya, M.B.; Listengarten, M.A.

    1976-01-01

    Presented here are internal conversion coefficients (ICC) of gamma rays for 20 values of atomic number, Z, in the range 3 less than or equal to Z less than or equal to 30, including all Z greater than or equal to 14. The tables provide the previously missing data for light elements. Coefficients are given for 19 values of gamma-ray transition energies up to 6 MeV for the K-electron shell and 18 values up to 2 MeV for three L-subshells. The minimum enegy is 15 keV. The first five electric and magnetic nuclear transition multipolarities are covered. The calculations are relativistic, with screening and finite nuclear size effect taken into account

  18. REIDAC. A software package for retrospective dose assessment in internal contamination with radionuclides

    International Nuclear Information System (INIS)

    Kurihara, Osamu; Kanai, Katsuta; Takada, Chie; Takasaki, Koji; Ito, Kimio; Momose, Takumaro; Hato, Shinji; Ikeda, Hiroshi; Oeda, Mikihiro; Kurosawa, Naohiro; Fukutsu, Kumiko; Yamada, Yuji; Akashi, Makoto

    2007-01-01

    For cases of internal contamination with radionuclides, it is necessary to perform an internal dose assessment to facilitate radiation protection. For this purpose, the ICRP has supplied the dose coefficients and the retention and excretion rates for various radionuclides. However, these dosimetric quantities are calculated under typical conditions and are not necessarily detailed enough for dose assessment situations in which specific information on the incident or/and individual biokinetic characteristics could or should be taken into account retrospectively. This paper describes a newly developed PC-based software package called Retrospective Internal Dose Assessment Code (REIDAC) that meets the needs of retrospective dose assessment. REIDAC is made up of a series of calculation programs and a package of software. The former calculates the dosimetric quantities for any radionuclide being assessed and the latter provides a user with the graphical user interface (GUI) for executing the programs, editing parameter values and displaying results. The accuracy of REIDAC was verified by comparisons with dosimetric quantities given in the ICRP publications. This paper presents the basic structure of REIDAC and its calculation methods. Sensitivity analysis of the aerosol size for 239 Pu compounds and provisional calculations for wound contamination with 241 Am were performed as examples of the practical application of REIDAC. (author)

  19. National and international considerations of a de minimis dose

    International Nuclear Information System (INIS)

    Kocher, D.C.

    1986-01-01

    This paper reviews current efforts by national and international agencies to establish a generally applicable de minimis radiation dose. A de minimis dose is derived from a level of risk that is widely regarded as negligible by the general public, and defines a level below which control of radiation exposures would be deliberately and specifically curtailed. A de minimis dose can be used to derive quantities of radionuclides in various materials that would be exempt or below regulatory concern for such purposes as resale, recycling, or disposal. The specification of exempt levels of radioactivity could lead to significant reductions in the required capacity of radioactive waste storage and disposal facilities and in the costs associated with management of slightly contaminated materials. A de minimis dose must be set well below the limit on acceptable dose for public exposures. A de minimis dose in the range 0.1-30 mrem (0.001-0.3 mSv) per year committed effective dose equivalent has been considered by various agencies, with most recommendations at 1 or 5 mrem per year. A value of 30 mrem per year may be too high for a de minimis dose, because a dose limit of 25 mrem per year is widely used in the US for regulating specific practices (e.g., low-level waste disposal). A value as low as 0.1 mrem per year could lead to great difficulties in measuring associated levels of radioactivity. We propose a de minimis dose of 1 mrem (0.01 mSv) per year committed effective dose equivalent averaged over a lifetime and 5 mrem (0.05 mSv) in any year

  20. Gamma dose from activation of internal shields in IRIS reactor.

    Science.gov (United States)

    Agosteo, Stefano; Cammi, Antonio; Garlati, Luisella; Lombardi, Carlo; Padovani, Enrico

    2005-01-01

    The International Reactor Innovative and Secure is a modular pressurised water reactor with an integral design. This means that all the primary system components, such as the steam generators, pumps, pressuriser and control rod drive mechanisms, are located inside the reactor vessel, which requires a large diameter. For the sake of better reliability and safety, it is desirable to achieve the reduction of vessel embrittlement as well as the lowering of the dose beyond the vessel. The former can be easily accomplished by the presence of a wide downcomer, filled with water, which surrounds the core region, while the latter needs the presence of additional internal shields. An optimal shielding configuration is under investigation, for reducing the ex-vessel dose due to activated internals and for limiting the amount of the biological shielding. MCNP 4C calculations were performed to evaluate the neutron and the gamma dose during operation and the 60Co activation of various shields configurations. The gamma dose beyond the vessel from activation of its structural components was estimated in a shutdown condition, with the Monte Carlo code FLUKA 2002 and the MicroShield software. The results of the two codes are in agreement and show that the dose is sufficiently low, even without an additional shield.

  1. Gamma dose from activation of internal shields in IRIS reactor

    International Nuclear Information System (INIS)

    Agosteo, S.; Cammi, A.; Garlati, L.; Lombardi, C.; Padovani, E.

    2005-01-01

    The International Reactor Innovative and Secure is a modular pressurised water reactor with an integral design. This means that all the primary system components, such as the steam generators, pumps, pressurizer and control rod drive mechanisms, are located inside the reactor vessel, which requires a large diameter. For the sake of better reliability and safety, it is desirable to achieve the reduction of vessel embrittlement as well as the lowering of the dose beyond the vessel. The former can be easily accomplished by the presence of a wide downcomer, filled with water, which surrounds the core region, while the latter needs the presence of additional internal shields. An optimal shielding configuration is under investigation, for reducing the ex-vessel dose due to activated internals and for limiting the amount of the biological shielding. MCNP 4C calculations were performed to evaluate the neutron and the gamma dose during operation and the 60 Co activation of various shields configurations. The gamma dose beyond the vessel from activation of its structural components was estimated in a shutdown condition, with the Monte Carlo code FLUKA 2002 and the MicroShield software. The results of the two codes are in agreement and show that the dose is sufficiently low, even without an additional shield. (authors)

  2. Standardization and determination of the total internal conversion coefficient of In-111.

    Science.gov (United States)

    Matos, Izabela T; Koskinas, Marina F; Nascimento, Tatiane S; Yamazaki, Ione M; Dias, Mauro S

    2014-05-01

    The standardization of (111)In by means of a 4πβ-γ coincidence system, composed of a proportional counter in 4π geometry, coupled to a 20% relative efficiency HPGe crystal, for measuring gamma-rays is presented. The data acquisition was performed by means of the software coincidence system (SCS) and the activity was determined by the extrapolation technique. Two gamma-ray windows were selected: at 171 keV and 245 keV total absorption peaks, allowing the determination of the total internal conversion coefficient for these two gamma transitions. The results were compared with those available in the literature. © 2013 Published by Elsevier Ltd.

  3. Calculation of neutron fluence to dose equivalent conversion coefficients using GEANT4; Calculo de coeficientes de fluencia de neutrons para equivalente de dose individual utilizando o GEANT4

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, Rosane M.; Santos, Denison de S.; Queiroz Filho, Pedro P. de; Mauricio, CLaudia L.P.; Silva, Livia K. da; Pessanha, Paula R., E-mail: rosanemribeiro@oi.com.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2014-07-01

    Fluence to dose equivalent conversion coefficients provide the basis for the calculation of area and personal monitors. Recently, the ICRP has started a revision of these coefficients, including new Monte Carlo codes for benchmarking. So far, little information is available about neutron transport below 10 MeV in tissue-equivalent (TE) material performed with Monte Carlo GEANT4 code. The objective of this work is to calculate neutron fluence to personal dose equivalent conversion coefficients, H{sub p} (10)/Φ, with GEANT4 code. The incidence of monoenergetic neutrons was simulated as an expanded and aligned field, with energies ranging between thermal neutrons to 10 MeV on the ICRU slab of dimension 30 x 30 x 15 cm{sup 3}, composed of 76.2% of oxygen, 10.1% of hydrogen, 11.1% of carbon and 2.6% of nitrogen. For all incident energy, a cylindrical sensitive volume is placed at a depth of 10 mm, in the largest surface of the slab (30 x 30 cm{sup 2}). Physic process are included for neutrons, photons and charged particles, and calculations are made for neutrons and secondary particles which reach the sensitive volume. Results obtained are thus compared with values published in ICRP 74. Neutron fluence in the sensitive volume was calculated for benchmarking. The Monte Carlo GEANT4 code was found to be appropriate to calculate neutron doses at energies below 10 MeV correctly. (author)

  4. Dose Calculation Evolution for Internal Organ Irradiation in Humans

    International Nuclear Information System (INIS)

    Jimenez V, Reina A.

    2007-01-01

    The International Commission of Radiation Units (ICRU) has established through the years, a discrimination system regarding the security levels on the prescription and administration of doses in radiation treatments (Radiotherapy, Brach therapy, Nuclear Medicine). The first level is concerned with the prescription and posterior assurance of dose administration to a point of interest (POI), commonly located at the geometrical center of the region to be treated. In this, the effects of radiation around that POI, is not a priority. The second level refers to the dose specifications in a particular plane inside the patient, mostly the middle plane of the lesion. The dose is calculated to all the structures in that plane regardless if they are tumor or healthy tissue. In this case, the dose is not represented by a point value, but by level curves called 'isodoses' as in a topographic map, so you can assure the level of doses to this particular plane, but it also leave with no information about how this values go thru adjacent planes. This is why the third level is referred to the volumetrical description of doses so these isodoses construct now a volume (named 'cloud') that give us better assurance about tissue irradiation around the volume of the lesion and its margin (sub clinical spread or microscopic illness). This work shows how this evolution has resulted, not only in healthy tissue protection improvement but in a rise of tumor control, quality of life, better treatment tolerance and minimum permanent secuelae

  5. Establishment of detailed eye model of adult chinese male and dose conversion coefficients calculation under neutron exposure

    International Nuclear Information System (INIS)

    Zhu, Hongyu; Qiu, Rui; Ren, Li; Zhang, Hui; Li, Junli; Wu, Zhen; Li, Chunyan

    2017-01-01

    The human eye lens is sensitive to radiation. ICRP-118 publication recommended a reduction of the occupational annual equivalent dose limit from 150 to 20 mSv, averaged over defined periods of 5 y. Therefore, it is very important to build a detailed eye model for the accurate dose assessment and radiation risk evaluation of eye lens. In this work, a detailed eye model was build based on the characteristic anatomic parameters of the Chinese adult male. This eye model includes seven main structures, which are scleral, choroid, lens, iris, cornea, vitreous body and aqueous humor. The lens was divided into sensitive volume and insensitive volume based on different cell populations. The detailed eye model was incorporated into the converted polygon-mesh version of the Chinese reference adult male whole-body surface model. After the incorporation, dose conversion coefficients for the eye lens were calculated for neutron exposure at AP, PA and LAT geometries with Geant4, the neutron energies were from 0.001 eV to 10 MeV. The calculated lens dose coefficients were compared with those of ICRP-116 publication. Significant differences up to 97.47% were found at PA geometry. This could mainly be attributed to the different geometry characteristic of eye model and parameters of head in different phantom between the present work and ICRP-116 publication. (authors)

  6. ESTABLISHMENT OF DETAILED EYE MODEL OF ADULT CHINESE MALE AND DOSE CONVERSION COEFFICIENTS CALCULATION UNDER NEUTRON EXPOSURE.

    Science.gov (United States)

    Zhu, Hongyu; Qiu, Rui; Wu, Zhen; Ren, Li; Li, Chunyan; Zhang, Hui; Li, Junli

    2017-12-01

    The human eye lens is sensitive to radiation. ICRP-118 publication recommended a reduction of the occupational annual equivalent dose limit from 150 to 20 mSv, averaged over defined periods of 5 y. Therefore, it is very important to build a detailed eye model for the accurate dose assessment and radiation risk evaluation of eye lens. In this work, a detailed eye model was build based on the characteristic anatomic parameters of the Chinese adult male. This eye model includes seven main structures, which are scleral, choroid, lens, iris, cornea, vitreous body and aqueous humor. The lens was divided into sensitive volume and insensitive volume based on different cell populations. The detailed eye model was incorporated into the converted polygon-mesh version of the Chinese reference adult male whole-body surface model. After the incorporation, dose conversion coefficients for the eye lens were calculated for neutron exposure at AP, PA and LAT geometries with Geant4, the neutron energies were from 0.001 eV to 10 MeV. The calculated lens dose coefficients were compared with those of ICRP-116 publication. Significant differences up to 97.47% were found at PA geometry. This could mainly be attributed to the different geometry characteristic of eye model and parameters of head in different phantom between the present work and ICRP-116 publication. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  7. Guidance on internal dose assessments from monitoring data (Project IDEAS)

    International Nuclear Information System (INIS)

    Doerfel, H.; Andrasi, A.; Bailey, M.; Berkovski, V.; Castellani, M.; Hurtgen, C.; Jourdain, R.; Le Guen, B.

    2003-01-01

    Several international intercomparison exercises on intake and internal dose assessments from monitoring data led to the conclusion that the results calculated by different participants varied significantly mainly to the broad variety of methods and assumptions applied in the assessment procedure. Based on these experiences the need of harmonisation of the procedures has been formulated as an EU research project under the 5th Framework Programme, with the aim of developing general guidelines for standardising assessments of intakes and internal doses. In the IDEAS project, eight institutions from seven European countries are participating, also using inputs from internal dosimetry professionals from across Europe to ensure broad consensus in the outcome of the project. To ensure that the guidelines are applicable to a wide range of practical situations, the first step will be to compile a database on well documented cases of internal contamination. In parallel, an improved version of existing software will be developed and distributed to the partners for further use. Many cases from the database will be evaluated independently by more partners using the same software and the results will be discussed and the draft guidelines prepared. The guidelines will then be revised and refined on the basis of the experiences and discussions of two workshops, and an inter-comparison exercise organised in the frame of the project which will be open to all internal dosimetry professionals. (author)

  8. Study of the coefficients of internal conversion for transition energies approaching the threshold

    International Nuclear Information System (INIS)

    Farani Coursol, Nelcy.

    1979-01-01

    Internal conversion coefficients were determined experimentally with great accuracy for areas of transition energies, which constitute tests for the theories (energies at the most ten kEv above the threshold of K shell), then the results obtained were compared with the values calculated (or to be calculated) from theoretical models. Owing to the difficulties raised by the precise determination of the internal conversion coefficients (ICC), in the first stage we selected radionuclides with a relatively simple decay pattern, the transitions: 30 keV of sup(93m)Nb, 35 keV of sup(125m)Te, 14 keV of 57 Fe and 39 keV of sup(129m)Xe. It was observed that 'problems' exist with respect to the ICC's of the great multipolarity transitions, so the transitions of this kind were examined in a systematic manner. The possibility of penetration effects occurring for the transitions studied experimentally was examined. The considerations are presented which 'authorized' us to disregard the dynamic part of the ICC for the transitions approaching the threshold (L selection rules and life of nuclear levels in relation to Weisskopf-Moszkowski estimations). The Kurie straight line was determined experimentally for the β - transition and the Qsub(β) was evaluated with an important accuracy gain compared with the values available at present. Finally, a certain number of ICC's of transitions already determined with good precision were recalculated, in order to extend our analysis and detect any possible systematic errors [fr

  9. Assessing the reliability of dose coefficients for exposure to radioiodine by members of the public, accounting for dosimetric and risk model uncertainties.

    Science.gov (United States)

    Puncher, M; Zhang, W; Harrison, J D; Wakeford, R

    2017-06-26

    Assessments of risk to a specific population group resulting from internal exposure to a particular radionuclide can be used to assess the reliability of the appropriate International Commission on Radiological Protection (ICRP) dose coefficients used as a radiation protection device for the specified exposure pathway. An estimate of the uncertainty on the associated risk is important for informing judgments on reliability; a derived uncertainty factor, UF, is an estimate of the 95% probable geometric difference between the best risk estimate and the nominal risk and is a useful tool for making this assessment. This paper describes the application of parameter uncertainty analysis to quantify uncertainties resulting from internal exposures to radioiodine by members of the public, specifically 1, 10 and 20-year old females from the population of England and Wales. Best estimates of thyroid cancer incidence risk (lifetime attributable risk) are calculated for ingestion or inhalation of 129 I and 131 I, accounting for uncertainties in biokinetic model and cancer risk model parameter values. These estimates are compared with the equivalent ICRP derived nominal age-, sex- and population-averaged estimates of excess thyroid cancer incidence to obtain UFs. Derived UF values for ingestion or inhalation of 131 I for 1 year, 10-year and 20-year olds are around 28, 12 and 6, respectively, when compared with ICRP Publication 103 nominal values, and 9, 7 and 14, respectively, when compared with ICRP Publication 60 values. Broadly similar results were obtained for 129 I. The uncertainties on risk estimates are largely determined by uncertainties on risk model parameters rather than uncertainties on biokinetic model parameters. An examination of the sensitivity of the results to the risk models and populations used in the calculations show variations in the central estimates of risk of a factor of around 2-3. It is assumed that the direct proportionality of excess thyroid cancer

  10. Breast internal dose measurements in a physical thoracic phantom

    Energy Technology Data Exchange (ETDEWEB)

    Silva, S.D.; Oliveira, M.A.; Castro, A.L.S.; Dias, H.G.; Nogueira, L.B.; Campos, T.P.R., E-mail: sadonatosilva@hotmail.com [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear; Hospital das Clinicas de Uberlandia, MG (Brazil). Departamento de Oncologia; Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Anatomia e Departamento de Imagem

    2017-10-01

    Radiotherapy is a cancer treatment intended to deposit the entire prescribed dose homogeneously into a target volume in order to eliminate the tumor and to spare the surrounding healthy tissues. This paper aimed to provide a dosimetric comparison between the treatment planning system (TPS) ECLIPSE from Varian Medical Systems and the internal dosimetric measurements in a breast phantom. The methodology consisted in performing a 3D conformal radiotherapy planning with two tangential opposite parallel fields applied to the synthetic breast in a thoracic phantom. The irradiation was reproduced in the Varian Linear accelerator, model SL - 20 Precise, 6 MV energy. EBT2 Radiochromic films, placed into the glandular equivalent tissue of the breast, were used to measure the spatial dose distribution. The absorbed dose was compared to those values predicted by the treatment planning system; besides, the dosimetric uncertainties were analyzed. The modal absorbed dose was in agreement with the prescribed value of 180 cGy, although few high dose points between 180 and 220 cGy were detected. The findings suggested a non-uniform dose distribution in the glandular tissue of the synthetic breast, similar to those found in the TPS, associated with the irregular anatomic breast shape and presence of inhomogeneities next to the thoracic wall generated by the low lung density. (author)

  11. International dose assurance service programme of the International Atomic Energy Agency

    International Nuclear Information System (INIS)

    Nam, J.W.

    1988-01-01

    In order to execute normalization of high-doses on an international scale and to further promote dosimetry as quality control measures in radiation processing, the International Dose Assurance Service (IDAS) has recently been initiated in the framework of a high-dose standardization programme. IDAS is being provided on the basis of an ''Agreement Concerning the Provision of a Dose Assurance Service by the IAEA to Irradiation Facilities in its Member States''. The aim of the IDAS programme will be to meet stringent requirements for standardization of dosimetry, and to achieve concerted international efforts for quality assurance of radiation processing. Details of the programme and the achievements made to date are discussed. (author). 5 refs

  12. Internal dose conversion factors for calculation of dose to the public

    International Nuclear Information System (INIS)

    1988-07-01

    This publication contains 50-year committed dose equivalent factors, in tabular form. The document is intended to be used as the primary reference by the US Department of Energy (DOE) and its contractors for calculating radiation dose equivalents for members of the public, resulting from ingestion or inhalation of radioactive materials. Its application is intended specifically for such materials released to the environment during routine DOE operations, except in those instances where compliance with 40 CFR 61 (National Emission Standards for Hazardous Air Pollutants) requires otherwise. However, the calculated values may be equally applicable to unusual releases or to occupational exposures. The use of these committed dose equivalent tables should ensure that doses to members of the public from internal exposures are calculated in a consistent manner at all DOE facilities

  13. A real-time internal dose assessment exercise

    International Nuclear Information System (INIS)

    Bingham, D.; Bull, R. K.

    2013-01-01

    A real-time internal dose assessment exercise has been conducted in which participants were required to make decisions about sampling requirements, seek relevant information about the 'incident' and make various interim dose assessments. At the end of the exercise, each participant was requested to make a formal assessment, providing statements of the methods, models and assumptions used in that assessment. In this paper we describe how the hypothetical assessment case was set up and the exercise was conducted, the responses of the participants and the assessments of dose that they made. Finally we discuss the lessons learnt from the exercise and suggest how the exercise may be adapted to a wider range of participants. (authors)

  14. Spatial distribution of absorbed dose onboard of International Space Station

    International Nuclear Information System (INIS)

    Jadrnickova, I.; Spumy, F.; Tateyama, R.; Yasuda, N.; Kawashima, H.; Kurano, M.; Uchihori, Y.; Kitamura, H.; Akatov, Yu.; Shurshakov, V.; Kobayashi, I.; Ohguchi, H.; Koguchi, Y.

    2009-01-01

    The passive detectors (LD and PNTD) were exposed onboard of Russian Service Module Qn the International Space Station (ISS) from August 2004 to October 2005 (425 days). The detectors were located at 6 different positions inside the Service Module and also in 32 pockets on the surface of the spherical tissue-equivalent phantom located in crew cabin. Distribution of absorbed doses and dose equivalents measured with passive detectors, as well as LET spectra of fluences of registered particles, are presented as the function of detectors' location. The variation of dose characteristics for different locations can be up to factor of 2. In some cases, data measured with passive detectors are also compared with the data obtained by means of active instruments. (authors)

  15. Internal radiation dose calculations with the INREM II computer code

    International Nuclear Information System (INIS)

    Dunning, D.E. Jr.; Killough, G.G.

    1978-01-01

    A computer code, INREM II, was developed to calculate the internal radiation dose equivalent to organs of man which results from the intake of a radionuclide by inhalation or ingestion. Deposition and removal of radioactivity from the respiratory tract is represented by the Internal Commission on Radiological Protection Task Group Lung Model. A four-segment catenary model of the gastrointestinal tract is used to estimate movement of radioactive material that is ingested, or swallowed after being cleared from the respiratory tract. Retention of radioactivity in other organs is specified by linear combinations of decaying exponential functions. The formation and decay of radioactive daughters is treated explicitly, with each radionuclide in the decay chain having its own uptake and retention parameters, as supplied by the user. The dose equivalent to a target organ is computed as the sum of contributions from each source organ in which radioactivity is assumed to be situated. This calculation utilizes a matrix of dosimetric S-factors (rem/μCi-day) supplied by the user for the particular choice of source and target organs. Output permits the evaluation of components of dose from cross-irradiations when penetrating radiations are present. INREM II has been utilized with current radioactive decay data and metabolic models to produce extensive tabulations of dose conversion factors for a reference adult for approximately 150 radionuclides of interest in environmental assessments of light-water-reactor fuel cycles. These dose conversion factors represent the 50-year dose commitment per microcurie intake of a given radionuclide for 22target organs including contributions from specified source organs and surplus activity in the rest of the body. These tabulations are particularly significant in their consistent use of contemporary models and data and in the detail of documentation

  16. Calculation of conversion coefficients of dose of a computational anthropomorphic simulator sit exposed to a plane source

    International Nuclear Information System (INIS)

    Santos, William S.; Carvalho Junior, Alberico B. de; Pereira, Ariana J.S.; Santos, Marcos S.; Maia, Ana F.

    2011-01-01

    In this paper conversion coefficients (CCs) of equivalent dose and effective in terms of kerma in the air were calculated suggested by the ICRP 74. These dose coefficients were calculated considering a plane radiation source and monoenergetic for a spectrum of energy varying from 10 keV to 2 MeV. The CCs were obtained for four geometries of irradiation, anterior-posterior, posterior-anterior, lateral right side and lateral left side. It was used the radiation transport code Visual Monte Carlo (VMC), and a anthropomorphic simulator of sit female voxel. The observed differences in the found values for the CCs at the four irradiation sceneries are direct results of the body organs disposition, and the distance of these organs to the irradiation source. The obtained CCs will be used for estimative more precise of dose in situations that the exposed individual be sit, as the normally the CCs available in the literature were calculated by using simulators always lying or on their feet

  17. 10 CFR 20.1202 - Compliance with requirements for summation of external and internal doses.

    Science.gov (United States)

    2010-01-01

    ... external and internal doses. (a) If the licensee is required to monitor under both §§ 20.1502 (a) and (b), the licensee shall demonstrate compliance with the dose limits by summing external and internal doses... compliance with the requirements for summation of external and internal doses by meeting one of the...

  18. Variation of solubility, biokinetics and dose coefficient of industrial uranium oxides according to the specific surface area

    International Nuclear Information System (INIS)

    Chazel, V.; Houpert, P.; Ansorbolo, E.; Henge-Napoli, M.H.; Paquet, F.

    2000-01-01

    The in vitro solubility, absorption to blood, lung retention and dose coefficient of industrial UO 2 samples were studied as a function of the specific surface area (SSA) of the particles. An in vitro study has been carried out on two samples of industrial UO 4 to compare the results with those obtained with UO 2 . Ten UO 2 samples supplied by different fuel factories or research laboratories, presented specific surface areas from 1.00 to 4.45 m 2 .g -1 . The wide range of values of SSA was due to the different conditions of fabrication. Dissolution tests in cell culture medium made on these ten samples have shown that the solubility increased 2.5-fold when the SSA increased 1.7-fold. The same tendency has been found for UO 4 , a soluble compound, and for U 3 O 8 , a moderately soluble compound. Four in vivo experiments carried out on rats by intratracheal instillation of dust suspensions of UO 2 , have highlighted the decrease in lung retention and the increase of absorption to blood with the SSA. The experimental absorption parameters calculated from the in vivo data allowed specific dose coefficients to be obtained which decreased from 6.6 to 4.3 μSv.Bq -1 when the SSA increased from 1.60 to 3.08 m 2 .g -1 . Thus, the medical monitoring of workers at the workplace has to take into account any change in the fabrication process of the uranium compound which can affect the physiochemical properties and consequently the dose coefficient. (author)

  19. A Quantitative Property-Property Relationship for the Internal Diffusion Coefficients of Organic Compounds in Solid Materials

    DEFF Research Database (Denmark)

    Huang, Lei; Fantke, Peter; Jolliet, Olivier

    2017-01-01

    of chemical-material combinations. This paper develops and evaluates a quantitative property-property relationship (QPPR) to predict diffusion coefficients for a wide range of organic chemicals and materials. We first compiled a training dataset of 1103 measured diffusion coefficients for 158 chemicals in 32......Indoor releases of organic chemicals encapsulated in solid materials are major contributors to human exposures and are directly related to the internal diffusion coefficient in solid materials. Existing correlations to estimate the diffusion coefficient are only valid for a limited number...... consolidated material types. Following a detailed analysis of the temperature influence, we developed a multiple linear regression model to predict diffusion coefficients as a function of chemical molecular weight (MW), temperature, and material type (adjusted R2 of 0.93). The internal validations showed...

  20. Dielectric parameters of blood plasma in rats at external and internal irradiation with sublethal doses

    International Nuclear Information System (INIS)

    Khadzhidekova, E.; Kiradzhiev, G.

    1991-01-01

    Sexually mature male rats have received external gamma irradiation with 50, 200 or 380 cGy, treated with 89 Sr (333 or 1665 kBq per rat, femur dose 70, resp. 290 cGy), or 144 Ce (370 kBq per rat, liver dose 70 cGy). Dielectric parameters (permittivity and conductivity) have been measured in the frequency range 1.4 - 17 Mhz on different terms (1 to 30th day after the treatment). For all groups and terms the coefficients and equations describing the relationship between the dielectric permittivity ε and the frequency ν of the changing electric field have been calculated. On the basis of dielectric parameters the relaxation time of the plasma protein molecules is determined. It has been shown that the changes in dielectric permittivity are expressed at different frequencies specific for a given dose; the same is established for the conditions of internal irradiation. The frequency dependence of the permittivity is described as an exponential curve analogous to that of the control but with a changed exponent. In applying higher doses or activities the relationship turns from exponential to parabolic. The relaxation time, expressing the changes in conformal state of macromolecules, varies but is in all cases longer than one of the controls for the whole period of study at external irradiation with 50 and 380 cGy. It is lower at irradiation with 200 cGy, as well as at internal irradiation. 3 tabs., 13 refs

  1. Ratios between effective doses for tomographic and mathematician models due to internal exposure of photons

    International Nuclear Information System (INIS)

    Lima, F.R.A.; Kramer, R.; Khoury, H.J.; Santos, A.M.; Loureiro, E.C.M.

    2005-01-01

    The development of new and sophisticated Monte Carlo codes and tomographic human phantoms or voxels motivated the International Commission on Radiological Protection (ICRP) to revise the traditional models of exposure, which have been used to calculate effective dose coefficients for organs and tissues based on mathematician phantoms known as MIRD5. This paper shows the results of calculations using tomographic phantoms MAX (Male Adult voXel) and FAX (Female Adult voXel), recently developed by the authors as well as with the phantoms ADAM and EVA, of specific genres, type MIRD5, coupled to the EGS4 Monte Carlo and MCNP4C codes, for internal exposure with photons of energies between 10 keV and 4 MeV to several organs sources. Effective Doses for both models, tomographic and mathematician, will be compared separately as a function of the Monte Carlo code replacement, of compositions of human tissues and the anatomy reproduced through tomographs. The results indicate that for photon internal exposure, the use of models of exposure based in voxel, increases the values of effective doses up to 70% for some organs sources considered in this study, when compared with the corresponding results obtained with phantoms of MIRD-5 type

  2. Internal doses to Ukrainian populations using Dnieper River water

    International Nuclear Information System (INIS)

    Berkovski, V.; Ratia, G.; Nasvit, O.

    1996-01-01

    The dynamics of internal doses from 137 Cs and 90 Sr as a consequence of the use of Dnieper River water were calculated. Local peculiarities of municipal tap, irrigation, and fish consumption in the Ukraine were considered. The dynamics of 90 Sr accumulation in human bone as a result of the use of Dnieper water is simulated. The dose predictions are based on de facto data and the stochastic forecast of radionuclide concentrations in Dnieper reservoirs. A large array of statistical data on the age-structures of exposed populations, food consumption rate, agricultural production, fish contamination, and site-specific parameters were used. Exposures are estimated for 12 regions of the Dnieper basin and the Crimea Republic. The maximal individual annual committed effective doses are 1.7 x 10 -5 and 2.7 x 10 -5 Sv from 90 Sr and 137 Cs, respectively, due to the use of water in 1986 by members of the population in the Kievska region. Commercial fishermen on the Kievska reservoir, who consumed 360 kg y -1 of fish in 1986, received 4.7 x 10 -4 and 5 x 10 -3 Sv from 90 Sr and 137 Cs, respectively. The contributions to the collective (over 70 6) effective dose of irrigation, municipal tap water, and fish consumption for members of the general public, respectively, are 18%, 43%,39% in the Kievska region; 8%,25%,67% in the Poltavska region; 50% 50%, 0% (no Dnieper fish consumed) in the Crimea Republic. The predicted contribution of 90 Sr to collective dose resulting from the use of water is 80%. The collective dose to the population of the Dnieper regions (32.5 million people) is 3,000 person-Sv, due to the use of water. 14 refs., 12 figs., 2 tabs

  3. Calculation of conversion coefficients for effective dose by using voxel phantoms with defined genus for radiodiagnostic common examinations

    International Nuclear Information System (INIS)

    Lima, F.R.A.; Kramer, R.; Khoury, H.J.; Vieira, J.W.; Loureiro, E.C.M.; Hoff, G.

    2004-01-01

    Patient exposure from radiological examinations is usually quantified in terms of average absorbed dose or equivalent dose to certain radiosensitive organs of the human body. As these quantities cannot be measured in vivo, it is common practice to use physical or computational exposure models, which simulate the exposure to the patient in order to determine not only the quantities of interest (absorbed or equivalent dose), but also at the same time measurable quantities for the exposure conditions given. The ratio between a quantity of interest and a measurable quantity is called a conversion coefficient (CC), which is a function of the source and field parameters (tube voltage, filtration, field size, field position, focus-to-skin distance, etc.), the anatomical properties of the phantom, the elemental composition of relevant body tissues, and the radiation transport method applied. As the effective dose represents a sum over 23 risk-weighted organ and tissue equivalent doses, its determination practically implies the measurement or calculation of a complete distribution of equivalent doses throughout the human body. This task can be resolved most efficiently by means of computational exposure models, which consist of a virtual representation of the human body, also called phantom, connected to a Monte Carlo radiation transport computer code. The recently introduced MAX (Male Adult voXel) and FAXht (Female Adult voXel) head+trunk phantoms have been chosen for this task. With respect to their anatomical properties these phantoms correspond fairly well to the data recommended by the ICRP for the Reference Adult Male and Female. (author)

  4. Clinical radiation doses for spinal cord: the 1988 international questionnaire

    International Nuclear Information System (INIS)

    Fowler, J.F.; Bogaert, W. vanden; Scheuren, E. van der; Bentzen, S.M.; Bond, S.J.; Ang, K.K.; Kogel, A.J. van der

    2000-01-01

    Emmanuel van der Schueren gave a keynote lecture at the 1988 ASTRO annual conference pointing out that the spinal cord 'tolerance doses' then prescribed were probably unnecessarily cautious, resulting in probable underdosing of some tumours. This lecture was supported both by an international questionnaire which he and two of the present authors had conducted, and by animal experimental data. In 1997 he initiated a 10-year follow-up questionnaire, the results of which are summarised here. The present report analyses the chance in prescriptions from 1988 to 1998 and the variation in prescriptions among various regions of the World. The main conclusion is that prescribed dose levels have increased significantly in this period. Large geographical variations still exist. Among responders who use a formula to correct for changed dose per fraction, 90% are now using the linear-quadratic model vs. 33% in 1988. The current status of clinically acceptable doses to spinal cord in 2-Gy fractions is discussed briefly. Further details from the responses to the 1998 questionnaire will be presented in another publication. (author)

  5. Air contamination measurements for the evaluation of internal dose to workers in nuclear medicine departments

    Science.gov (United States)

    De Massimi, B.; Bianchini, D.; Sarnelli, A.; D'Errico, V.; Marcocci, F.; Mezzenga, E.; Mostacci, D.

    2017-11-01

    Radionuclides handled in nuclear medicine departments are often characterized by high volatility and short half-life. It is generally difficult to monitor directly the intake of these short-lived radionuclides in hospital staff: this makes measuring air contamination of utmost interest. The aim of the present work is to provide a method for the evaluation of internal doses to workers in nuclear medicine, by means of an air activity sampling detector, to ensure that the limits prescribed by the relevant legislation are respected. A continuous air sampling system measures isotope concentration with a Nal(TI) detector. Energy efficiency of the system was assessed with GEANT4 and with known activities of 18F. Air is sampled in a number of areas of the nuclear medicine department of the IRST-IRCCS hospital (Meldola- Italy). To evaluate committed doses to hospital staff involved (doctors, technicians, nurses) different exposure situations (rooms, times, radionuclides etc) were considered. After estimating the intake, the committed effective dose has been evaluated, for the different radionuclides, using the dose coefficients mandated by the Italian legislation. Error propagation for the estimated intake and personal dose has been evaluated, starting from measurement statistics.

  6. Development of a computational methodology for internal dose calculations

    International Nuclear Information System (INIS)

    Yoriyaz, Helio

    2000-01-01

    A new approach for calculating internal dose estimates was developed through the use of a more realistic computational model of the human body and a more precise tool for the radiation transport simulation. The present technique shows the capability to build a patient-specific phantom with tomography data (a voxel-based phantom) for the simulation of radiation transport and energy deposition using Monte Carlo methods such as in the MCNP-4B code. In order to utilize the segmented human anatomy as a computational model for the simulation of radiation transport, an interface program, SCMS, was developed to build the geometric configurations for the phantom through the use of tomographic images. This procedure allows to calculate not only average dose values but also spatial distribution of dose in regions of interest. With the present methodology absorbed fractions for photons and electrons in various organs of the Zubal segmented phantom were calculated and compared to those reported for the mathematical phantoms of Snyder and Cristy-Eckerman. Although the differences in the organ's geometry between the phantoms are quite evident, the results demonstrate small discrepancies, however, in some cases, considerable discrepancies were found due to two major causes: differences in the organ masses between the phantoms and the occurrence of organ overlap in the Zubal segmented phantom, which is not considered in the mathematical phantom. This effect was quite evident for organ cross-irradiation from electrons. With the determination of spatial dose distribution it was demonstrated the possibility of evaluation of more detailed doses data than those obtained in conventional methods, which will give important information for the clinical analysis in therapeutic procedures and in radiobiologic studies of the human body. (author)

  7. Assessments of conversion coefficients between equivalent dose and accumulated activity using pre-dose scanning images of patients subjected to radioiodine treatment and the Fax/Egs4 computational model

    International Nuclear Information System (INIS)

    Lopes Filho, Ferdinand de J.; Vieira, Jose W.; Andrade Lima, Fernando R. de

    2008-01-01

    The radioiodine is a technique for treatment of thyroid cancer. In this technique, the patients are submitted to the incorporation of the radioactive substance sodium iodide (Na 131 I), which reacts with physiologically metastasis, thyroid tissue remains of and other organs and tissues of the human body. The locations of these reactions are known as areas of highest concentration, hipercaptured areas, hiperconcentrator areas, 'hot areas' or organ-sources and are viewed through images of nuclear medicine scan known as pre-dose (front and rear). To obtain these images, the patient receives, orally, a quantity of 131 I with low activity (± 74 MBq) and is positioned in the chamber of flicker. According to the attendance of hot areas shown in the images, the doctor determines the nuclear activity to be administered in treatment. This analysis is purely qualitative. In this study, the scanning images of pre-dose were adjusted to the dimensions of FAX voxel phantom, and the hot areas correspond to internal sources of the proposed model. Algorithms were developed to generate particles (photons and electrons) in these regions of the FAX. To estimate the coefficients of conversions between equivalent dose and accumulated activity in major radiosensitive organs, FAX and algorithms source were coupled to the Monte Carlo EGS4 code (Electron Gamma Shower, version 4). With these factors is possible to estimate the equivalent doses in the radiosensitive organs and tissues of patients as long as is know the activity administered and the half-life of organic sources. (author)

  8. Sensitivity of coefficients for converting entrance surface dose and kerma-area product to effective dose and energy imparted to the patient

    International Nuclear Information System (INIS)

    Wise, K.N.; Sandborg, M.; Persliden, J.; Alm Carlsson, G.

    1999-01-01

    We investigate the sensitivity of the conversions from entrance surface dose (ESD) or kerma-area product (KAP) to effective dose (E) or to energy imparted to the patient (ε) to the likely variations in tube potential, field size, patient size and sex which occur in clinical work. As part of a factorial design study for chest and lumbar spine examinations, the tube potentials were varied to be ±10% of the typical values for the examinations while field sizes and the positions of the field centres were varied to be representative of values drawn from measurements on patient images. Variation over sex and patient size was based on anthropomorphic phantoms representing males and females of ages 15 years (small adult) and 21 years (reference adult). All the conversion coefficients were estimated using a mathematical phantom programmed with the Monte Carlo code EGS4 for all factor combinations and analysed statistically to derive factor effects. In general, the factors studied behaved independently in the sense that interaction of the physical factors generally gave no more than a 5% variation in a conversion coefficient. Taken together, variation of patient size, sex, field size and field position can lead to significant variation of E/KAP by up to a factor of 2, of E/ESD by up to a factor of 3, of ε/KAP by a factor of 1.3 and of ε/ESD by up to a factor of 2. While KAP is preferred to determine ε, the results show no strong preference of KAP over ESD in determining E. The mean absorbed dose D-bar in the patient obtained by dividing ε (determined using KAP) by the patient's mass was found to be the most robust measure of E. (author)

  9. SU-D-209-06: Study On the Dose Conversion Coefficients in Pediatric Radiography with the Development of Children Voxel Phantoms

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Q [Institute of Radiation Medicine Fudan University, Shanghai (China); Shanghai General Hospital, Shanghai, Shanghai (China); Zhuo, W; Liu, H [Institute of Radiation Medicine Fudan University, Shanghai (China); Liu, Y; Chen, T [Shanghai General Hospital, Shanghai, Shanghai (China)

    2016-06-15

    Purpose: Conversion coefficients of organ dose normalized to entrance skin dose (ESD) are widely used to evaluate the organ doses directly using ESD without time-consuming dose measurement, this work aims to investigate the dose conversion coefficients in pediatric chest and abdomen radiography with the development of 5 years and 10 years old children voxel phantoms. Methods: After segmentation of organs and tissues from CT slice images of ATOM tissue-equivalent phantoms, a 5-year-old and a 10-year-old children computational voxel phantoms were developed for Monte Carlo simulation. The organ doses and the entrance skin dose for pediatric chest postero-anterior projection and abdominal antero-posterior projection were simulated at the same time, and then the organ dose conversion coefficients were calculated.To verify the simulated results, dose measurement was carried out with ATOM tissue-equivalent phantoms for 5 year chest radiography. Results: Simulated results and experimental results matched very well with each other, the result differences of all the organs covered in radiation field were below 16% for 5-year-old child in chest projection. I showed that the conversion coefficients of organs covered in the radiation field were much larger than organs out of the field for all the study cases, for example, the conversion coefficients of stomach, liver intestines, and pancreas are larger for abdomen radiography while conversion coefficients of lungs are larger for chest radiography. Conclusion: The voxel children phantoms were helpful to evaluate the radiation doses more accurately and efficiently. Radiation field was the essential factor that affects the organ dose, use reasonably small field should be encouraged for radiation protection. This work was supported by the National Natural Science Foundation of China(11475047)

  10. SU-D-209-06: Study On the Dose Conversion Coefficients in Pediatric Radiography with the Development of Children Voxel Phantoms

    International Nuclear Information System (INIS)

    Liu, Q; Zhuo, W; Liu, H; Liu, Y; Chen, T

    2016-01-01

    Purpose: Conversion coefficients of organ dose normalized to entrance skin dose (ESD) are widely used to evaluate the organ doses directly using ESD without time-consuming dose measurement, this work aims to investigate the dose conversion coefficients in pediatric chest and abdomen radiography with the development of 5 years and 10 years old children voxel phantoms. Methods: After segmentation of organs and tissues from CT slice images of ATOM tissue-equivalent phantoms, a 5-year-old and a 10-year-old children computational voxel phantoms were developed for Monte Carlo simulation. The organ doses and the entrance skin dose for pediatric chest postero-anterior projection and abdominal antero-posterior projection were simulated at the same time, and then the organ dose conversion coefficients were calculated.To verify the simulated results, dose measurement was carried out with ATOM tissue-equivalent phantoms for 5 year chest radiography. Results: Simulated results and experimental results matched very well with each other, the result differences of all the organs covered in radiation field were below 16% for 5-year-old child in chest projection. I showed that the conversion coefficients of organs covered in the radiation field were much larger than organs out of the field for all the study cases, for example, the conversion coefficients of stomach, liver intestines, and pancreas are larger for abdomen radiography while conversion coefficients of lungs are larger for chest radiography. Conclusion: The voxel children phantoms were helpful to evaluate the radiation doses more accurately and efficiently. Radiation field was the essential factor that affects the organ dose, use reasonably small field should be encouraged for radiation protection. This work was supported by the National Natural Science Foundation of China(11475047)

  11. Monte Carlo Method in the calculate of conversion coefficients for dose in children's organs and tissues subjected to dentistric radiography

    International Nuclear Information System (INIS)

    Loureiro, E.C.M.; Khoury, H.; Lima, F.R.A.

    1998-01-01

    The increasing utilization of oral X-rays, specially in youngsters and children, prompts the assessment of equivalent doses in their organs and tissues. With this purpose, Monte Carlo code was adopted to simulate an X-ray source irradiating phantoms of the MIRD-5 type with different ages (10, 15 and 40 years old) to calculate the conversion coefficients which transform the exposure at skin to equivalent doses at several organs and tissues of interest. In order to check the computer program, simulations were performed for adult patients using the original code (ADAM,FOR developed by GSF Germany) and the adapted program (MCDRO,PAS). Good agreement between results obtained by both programs was observed. Applications to incisive, canine and molar teeth were simulated. The conversion factors were calculated for the following organs and tissues: thyroid, active bone marrow (head and whole body), bone (facial skeleton, cranium and whole body), skin (head and whole body) and crystalline. Based on the obtained results, it follows that the younger the patient and the langer the field area, the higher the doses in assessed organs and tissues

  12. Age-specific effective doses for pediatric MSCT examinations at a large children's hospital using DLP conversion coefficients: a simple estimation method

    International Nuclear Information System (INIS)

    Thomas, Karen E.; Wang, Bo

    2008-01-01

    There is a need for an easily accessible method for effective dose estimation in pediatric CT. To estimate effective doses for a variety of pediatric neurological and body CT examinations in five age groups using recently published age- and region-specific dose length product (DLP) to effective dose conversion coefficients. A retrospective review was performed of 1,431 consecutive CT scans over a 12-week period using age- and weight-adjusted CT protocols. Age- and region-specific DLP to effective dose conversion coefficients were applied to console-displayed DLP data. Effective dose estimates for single-phase head CT scans in neonatal, and 1-, 5-, 10- and 15-year-old age groups were 4.2, 3.6, 2.4, 2.0 and 1.4 mSv, respectively. For abdomen/pelvis CT scans the corresponding effective doses were 13.1, 11.1, 8.4, 8.9 and 5.9 mSv. The range of pediatric CT effective doses is wide, from ultralow dose protocols (<1 mSv) to extended-coverage body examinations (10-15 mSv). Age- and region-specific pediatric DLP to effective dose conversion coefficients provide an accessible and user-friendly method for estimating pediatric CT effective doses that is available to radiologists working without medical physics support. (orig.)

  13. 10 CFR 835.203 - Combining internal and external equivalent doses.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Combining internal and external equivalent doses. 835.203 Section 835.203 Energy DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Standards for Internal and External Exposure § 835.203 Combining internal and external equivalent doses. (a) The total effective dose...

  14. Considerations of beta and electron transport in internal dose calculations

    International Nuclear Information System (INIS)

    Bolch, W.E.; Poston, J.W. Sr.

    1990-12-01

    Ionizing radiation has broad uses in modern science and medicine. These uses often require the calculation of energy deposition in the irradiated media and, usually, the medium of interest is the human body. Energy deposition from radioactive sources within the human body and the effects of such deposition are considered in the field of internal dosimetry. In July of 1988, a three-year research project was initiated by the Nuclear Engineering Department at Texas A ampersand M University under the sponsorship of the US Department of Energy. The main thrust of the research was to consider, for the first time, the detailed spatial transport of electron and beta particles in the estimation of average organ doses under the Medical Internal Radiation Dose (MIRD) schema. At the present time (December of 1990), research activities are continuing within five areas. Several are new initiatives begun within the second or third year of the current contract period. They include: (1) development of small-scale dosimetry; (2) development of a differential volume phantom; (3) development of a dosimetric bone model; (4) assessment of the new ICRP lung model; and (5) studies into the mechanisms of DNA damage. A progress report is given for each of these tasks within the Comprehensive Report. In each use, preliminary results are very encouraging and plans for further research are detailed within this document. 22 refs., 13 figs., 1 tab

  15. Considerations of beta and electron transport in internal dose calculations

    Energy Technology Data Exchange (ETDEWEB)

    Bolch, W.E.; Poston, J.W. Sr.

    1990-12-01

    Ionizing radiation has broad uses in modern science and medicine. These uses often require the calculation of energy deposition in the irradiated media and, usually, the medium of interest is the human body. Energy deposition from radioactive sources within the human body and the effects of such deposition are considered in the field of internal dosimetry. In July of 1988, a three-year research project was initiated by the Nuclear Engineering Department at Texas A M University under the sponsorship of the US Department of Energy. The main thrust of the research was to consider, for the first time, the detailed spatial transport of electron and beta particles in the estimation of average organ doses under the Medical Internal Radiation Dose (MIRD) schema. At the present time (December of 1990), research activities are continuing within five areas. Several are new initiatives begun within the second or third year of the current contract period. They include: (1) development of small-scale dosimetry; (2) development of a differential volume phantom; (3) development of a dosimetric bone model; (4) assessment of the new ICRP lung model; and (5) studies into the mechanisms of DNA damage. A progress report is given for each of these tasks within the Comprehensive Report. In each case, preliminary results are very encouraging and plans for further research are detailed within this document.

  16. Considerations of beta and electron transport in internal dose calculations

    Energy Technology Data Exchange (ETDEWEB)

    Bolch, W.E.; Poston, J.W. Sr. (Texas A and M Univ., College Station, TX (USA). Dept. of Nuclear Engineering)

    1990-12-01

    Ionizing radiation has broad uses in modern science and medicine. These uses often require the calculation of energy deposition in the irradiated media and, usually, the medium of interest is the human body. Energy deposition from radioactive sources within the human body and the effects of such deposition are considered in the field of internal dosimetry. In July of 1988, a three-year research project was initiated by the Nuclear Engineering Department at Texas A M University under the sponsorship of the US Department of Energy. The main thrust of the research was to consider, for the first time, the detailed spatial transport of electron and beta particles in the estimation of average organ doses under the Medical Internal Radiation Dose (MIRD) schema. At the present time (December of 1990), research activities are continuing within five areas. Several are new initiatives begun within the second or third year of the current contract period. They include: (1) development of small-scale dosimetry; (2) development of a differential volume phantom; (3) development of a dosimetric bone model; (4) assessment of the new ICRP lung model; and (5) studies into the mechanisms of DNA damage. A progress report is given for each of these tasks within the Comprehensive Report. In each use, preliminary results are very encouraging and plans for further research are detailed within this document. 22 refs., 13 figs., 1 tab.

  17. Considerations of beta and electron transport in internal dose calculations

    International Nuclear Information System (INIS)

    Bolch, W.E.; Poston, J.W. Sr.

    1990-12-01

    Ionizing radiation has broad uses in modern science and medicine. These uses often require the calculation of energy deposition in the irradiated media and, usually, the medium of interest is the human body. Energy deposition from radioactive sources within the human body and the effects of such deposition are considered in the field of internal dosimetry. In July of 1988, a three-year research project was initiated by the Nuclear Engineering Department at Texas A ampersand M University under the sponsorship of the US Department of Energy. The main thrust of the research was to consider, for the first time, the detailed spatial transport of electron and beta particles in the estimation of average organ doses under the Medical Internal Radiation Dose (MIRD) schema. At the present time (December of 1990), research activities are continuing within five areas. Several are new initiatives begun within the second or third year of the current contract period. They include: (1) development of small-scale dosimetry; (2) development of a differential volume phantom; (3) development of a dosimetric bone model; (4) assessment of the new ICRP lung model; and (5) studies into the mechanisms of DNA damage. A progress report is given for each of these tasks within the Comprehensive Report. In each case, preliminary results are very encouraging and plans for further research are detailed within this document

  18. Pure E2 transitions: A test for BRICC Internal Conversion Coefficients

    International Nuclear Information System (INIS)

    Gerl, J.; Sai, K. Vijay; Sainath, M.; Gowrishankar, R.; Venkataramaniah, K.

    2009-01-01

    The most widely used theoretical internal conversion coefficient (ICC) tables are of Hager and Seltzer (HS), Rosel et al. and BRICC (Band et al. tables using BRICC interpolation code). A rigorous comparison of experimental ICCs with various theoretical tabulations is possible only when a large data on experimental ICCs is available at one place. For this reason, a compilation of all the available experimental ICCs, α T , α K , α L of E2 transitions for a number of elements in the range of 24≤Z≤94 is presented. Listing of experimental data includes 595 datasets corresponding to 505 E2 transitions in 165 nuclei across the nuclear chart. Data with less than 10% experimental uncertainty have been selected for comparison with the theoretical values of Hager and Seltzer, Rosel et al. and BRICC. The relative percentage deviation (%Δ) have been calculated for each of the above theories and the average (%Δ) are estimated. The Band et al. tables, using the BRICC interpolation code are seen to give theoretical ICCs closest to experimental values.

  19. International Conference on Low Doses of Ionising Radiation

    International Nuclear Information System (INIS)

    McEwan, A.C.

    1998-01-01

    Is there a threshold? and is a little radiation good for you? were two questions raised at the International Conference on Low Doses of Ionising Radiation : Biological Effects and Regulatory Control, jointly organised by the IAEA and WHO, and convened in Seville, Spain, over 17-21 November 1997. The answer to both these questions appears to be 'Maybe', but the answer has no present implications for radiation protection practice and regulation. The conference which had over 500 participants from 65 countries, was organised around ten fora which explored basic molecular mechanisms of radiation effects, through to radiation protection principles and implementation in practices and interventions. Each forum was introduced by an overview presentation by an invited keynote speaker. Brief presentations of a few of the proffered papers followed, and then open discussion. There was opportunity for all proffered papers to be presented as posters. The fora, which occupied 3 full days, were preceded by reports on biological effects of radiation from international orgnaisations, and on related international conferences held in the recent past. The fora were followed by round table presentations of regulatory control and scientiFic research, and a summary session drawing together conclusions on the topic areas of the conference. (author)

  20. The internal radiation dose calculations based on Chinese mathematical phantom

    International Nuclear Information System (INIS)

    Wang Haiyan; Li Junli; Cheng Jianping; Fan Jiajin

    2006-01-01

    The internal radiation dose calculations built on Chinese facts become more and more important according to the development of nuclear medicine. the MIRD method developed and consummated by the society of Nuclear Medicine (America) is based on the European and American mathematical phantom and can't fit Chinese well. The transport of γ-ray in the Chinese mathematical phantom was simulated with Monte Carlo method in programs as MCNP4C. the specific absorbed fraction (Φ) of Chinese were calculated and the Chinese Φ database was created. The results were compared with the recommended values by ORNL. the method was proved correct by the coherence when the target organ was the same with the source organ. Else, the difference was due to the different phantom and the choice of different physical model. (authors)

  1. Polonium in mainstream cigarette smoke and associated internal radiation dose

    International Nuclear Information System (INIS)

    Tiwari, M.; Rathod, T.D.; Bhangare, R.C.; Ajmal, P.Y.; Maity, S.; Sahu, S.K.; Pandit, G.G.

    2015-01-01

    210 Po activity concentrations in cigarettes tobacco, mainstream cigarette smoke (MCS), ash and post smoking filter were measured by alpha spectrometry using surface barrier detectors, following the radiochemical separation of polonium. The results of present study indicate that the average (range) activity concentration of 210 Po in cigarette tobacco were 9.77 to 15.34 mBq per cigarette. The combined annual effective doses due to internal exposure of 210 Po and 210 Pb for a smoker (considering on an average 20 cigarette a day and 50% of MCS getting deposited in respiratory tract) were found to be ranging from 0.28 to 0.40 mSv for tested brands of cigarette. (author)

  2. International comparison of calibration standards for exposure and absorbed dose

    International Nuclear Information System (INIS)

    Horakova, I.; Wagner, R.

    1990-01-01

    A comparison was performed of the primary calibration standards for 60 Co gamma radiation dose from Czechoslovakia (UDZ CSAV, Prague), Austria (OEFZS/BEV Seibersdorf) and Hungary (OMH Budapest) using ND 1005 (absolute measurement) and V-415 (by means of N x ) graphite ionization chambers. BEV achieved agreement better than 0.1%, OMH 0.35%. Good agreement was also achieved for the values of exposure obtained in absolute values and those obtained via N x , this for the ND 1005/8105 chamber. The first ever international comparison involving Czechoslovakia was also performed of the unit of absorbed gamma radiation in a water and/or graphite phantom. The participants included Czechoslovakia (UDZ CSAV Prague), the USSR (VNIIFTRI Moscow) and Austria (OEFZS/BEV Seibersdorf). In all measurements, the agreement was better than 1%, which, in view of the differences in methodologies (VNIIFTRI, BEV: calorimetry, UDZ, UVVVR: ionometry) and the overall inaccuracies in determining the absorbed dose values, is a good result. (author)

  3. Analysis of internal doses to Mole voles inhabiting the East-Ural radioactive trace

    Energy Technology Data Exchange (ETDEWEB)

    Malinovsky, G.; Yarmoshenko, I. [Institute of Industrial Ecology UB RAS (Russian Federation); Chibiryak, M.; Vasil' ev, A. [Institute of Plant and Animal Ecology UB RAS (Russian Federation)

    2014-07-01

    Substantial task of development of approaches to radiation protection of non-human biota is investigation of relationships of exposure to dose, and dose to effects. Small mammals inhabiting territory of the East-Ural Radioactive Trace (EURT) are affected to ionizing radiation for many generations after accident at Mayak plutonium production in 1957. According to results of numerous studies a number of effects of exposure are observed. It is remarkable that the revealed effects are both negative and adaptive. In particular, the analysis of the variability of morphological structures of the axial skull and lower jaw in the population of northern mole vole (Ellobius talpinus Pall.), the burrowing rodent inhabiting the EURT, is of great interest. At the same time there is no reliable assessment of the radiation doses to these animals. Earlier we developed the approach to assess internal doses to mouse-like rodents (mice and voles) caused by incorporated {sup 90}Sr, which is the main dose contributing radionuclide at the EURT. Dose assessments are based on the results of beta-radiometry of intact bone. Routine methods for measuring the activity concentration of {sup 90}Sr in skeleton require ashing of samples, however in morphometric studies the destruction of material should be avoided: the skulls of mole voles are stored in the environmental samples depository of IPAE. Coefficients linking results of beta-radiometry of intact bone and activity concentration of {sup 90}Sr in skull of mouse was obtained basing on comparison of results of beta-radiometry of intact bone and bone ash. Obtained coefficients cannot be directly applied for calculating activity concentration of {sup 90}Sr in mole vole skulls because they are significantly larger. Therefore the additional study is required to assess proper coefficient of conversion from beta-radiometry to activity concentration of {sup 90}Sr. Developed dose assessment procedure includes application of the published values of

  4. Estimators of internal consistency in health research: the use of the alpha coefficient

    OpenAIRE

    Cascaes da Silva, Fraciele; Centro de Ciencias de la Salud y del Deporte, Universidad del Estado de Santa Catarina, Santa Catarina, Brasil.; Gonçalves, Elizandra; Centro de Ciencias de la Salud y del Deporte, Universidad del Estado de Santa Catarina, Santa Catarina, Brasil.; Valdivia Arancibia, Beatriz Angélica; Centro de Ciencias de la Salud y del Deporte, Universidad del Estado de Santa Catarina, Santa Catarina, Brasil; Graziele Bento, Salma; Centro de Ciencias de la Salud y del Deporte, Universidad del Estado de Santa Catarina, Santa Catarina, Brasil.; da Silva Castro, Thiago Luis; Centro de Ciencias de la Salud y del Deporte, Universidad del Estado de Santa Catarina, Santa Catarina, Brasil; Soleman Hernandez, Salma Stephany; Centro de Ciencias de la Salud y del Deporte, Universidad del Estado de Santa Catarina, Santa Catarina, Brasil; da Silva, Rudney; Centro de Ciencias de la Salud y del Deporte, Universidad del Estado de Santa Catarina, Santa Catarina, Brasil

    2015-01-01

    Academic production has increased in the area of health, increasingly demanding high quality in publications of great impact. One of the ways to consider quality is through methods that increase the consistency of data analysis, such as reliability which, depending on the type of data, can be evaluated by different coefficients, especially the alpha coefficient. Based on this, the present review systematically gathers scientific articles produced in the last five years, which in a methodologi...

  5. Comparison of internal dose estimates obtained using organ-level, voxel S value, and Monte Carlo techniques

    Energy Technology Data Exchange (ETDEWEB)

    Grimes, Joshua, E-mail: grimes.joshua@mayo.edu [Department of Physics and Astronomy, University of British Columbia, Vancouver V5Z 1L8 (Canada); Celler, Anna [Department of Radiology, University of British Columbia, Vancouver V5Z 1L8 (Canada)

    2014-09-15

    Purpose: The authors’ objective was to compare internal dose estimates obtained using the Organ Level Dose Assessment with Exponential Modeling (OLINDA/EXM) software, the voxel S value technique, and Monte Carlo simulation. Monte Carlo dose estimates were used as the reference standard to assess the impact of patient-specific anatomy on the final dose estimate. Methods: Six patients injected with{sup 99m}Tc-hydrazinonicotinamide-Tyr{sup 3}-octreotide were included in this study. A hybrid planar/SPECT imaging protocol was used to estimate {sup 99m}Tc time-integrated activity coefficients (TIACs) for kidneys, liver, spleen, and tumors. Additionally, TIACs were predicted for {sup 131}I, {sup 177}Lu, and {sup 90}Y assuming the same biological half-lives as the {sup 99m}Tc labeled tracer. The TIACs were used as input for OLINDA/EXM for organ-level dose calculation and voxel level dosimetry was performed using the voxel S value method and Monte Carlo simulation. Dose estimates for {sup 99m}Tc, {sup 131}I, {sup 177}Lu, and {sup 90}Y distributions were evaluated by comparing (i) organ-level S values corresponding to each method, (ii) total tumor and organ doses, (iii) differences in right and left kidney doses, and (iv) voxelized dose distributions calculated by Monte Carlo and the voxel S value technique. Results: The S values for all investigated radionuclides used by OLINDA/EXM and the corresponding patient-specific S values calculated by Monte Carlo agreed within 2.3% on average for self-irradiation, and differed by as much as 105% for cross-organ irradiation. Total organ doses calculated by OLINDA/EXM and the voxel S value technique agreed with Monte Carlo results within approximately ±7%. Differences between right and left kidney doses determined by Monte Carlo were as high as 73%. Comparison of the Monte Carlo and voxel S value dose distributions showed that each method produced similar dose volume histograms with a minimum dose covering 90% of the volume (D90

  6. Improvement of dose evaluation system for employees at severe accident in a nuclear power plant. Introduction of the dose rate conversion coefficient and addition of the access route edit function

    International Nuclear Information System (INIS)

    Sasaki, Yasuhiro; Minami, Noritoshi; Yoshida, Yoshitaka

    2006-01-01

    Institute of Nuclear Safety System, Inc. had developed the dose evaluation system to evaluate the radiation dose of employees at severe accident in a nuclear power plant. This system has features, which are (1) the dose rate of any evaluation point can be evaluated, (2) the dose rate at any time can be evaluated in consideration of the change in the radioactive source, (3) the dose rate map in the plant can be displayed (4) the dose along the access route when moving can be evaluated, and it is possible to use it for examination of the accident management guideline on the dose side etc.. To upgrade the dose evaluation function of this system, the improvements had been done which were introduction of the dose rate conversion coefficient and addition of the access route edit function. By introducing the dose rate conversion coefficient, the calculation time of the dose rate map in the plant was shortened at about 20 seconds, and a new function to evaluate time-dependent dose rate of any evaluation point was added. By adding the access route edit function, it became possible to re-calculate the dose easily at the route change. (author)

  7. Comparing Hp(3) evaluated from the conversion coefficients from air kerma to personal dose equivalent for eye lens dosimetry calibrated on a new cylindrical PMMA phantom

    Science.gov (United States)

    Esor, J.; Sudchai, W.; Monthonwattana, S.; Pungkun, V.; Intang, A.

    2017-06-01

    Based on a new occupational dose limit recommended by ICRP (2011), the annual dose limit for the lens of the eye for workers should be reduced from 150 mSv/y to 20 mSv/y averaged over 5 consecutive years in which no single year exceeding 50 mSv. This new dose limit directly affects radiologists and cardiologists whose work involves high radiation exposure over 20 mSv/y. Eye lens dosimetry (Hp(3)) has become increasingly important and should be evaluated directly based on dosimeters that are worn closely to the eye. Normally, Hp(3) dose algorithm was carried out by the combination of Hp(0.07) and Hp(10) values while dosimeters were calibrated on slab PMMA phantom. Recently, there were three reports from European Union that have shown the conversion coefficients from air kerma to Hp(3). These conversion coefficients carried out by ORAMED, PTB and CEA Saclay projects were performed by using a new cylindrical head phantom. In this study, various delivered doses were calculated using those three conversion coefficients while nanoDot, small OSL dosimeters, were used for Hp(3) measurement. These calibrations were performed with a standard X-ray generator at Secondary Standard Dosimetry Laboratory (SSDL). Delivered doses (Hp(3)) using those three conversion coefficients were compared with Hp(3) from nanoDot measurements. The results showed that percentage differences between delivered doses evaluated from the conversion coefficient of each project and Hp(3) doses evaluated from the nanoDots were found to be not exceeding -11.48 %, -8.85 % and -8.85 % for ORAMED, PTB and CEA Saclay project, respectively.

  8. A study on the determination of diffusion coefficient of carbon in 304 austenitic stainless steels by internal friction method

    International Nuclear Information System (INIS)

    Kim, K.S.; Kim, T.H.

    1982-01-01

    Internal friction peaks associated with the presence of carbon in 18-8 type 304 stainless steel have been observed from measurements with a torsion pendulum. The temperature for maximum internal friction lies between 250degC and 300degC with a frequency of vibration. The height of the peak rises and the position of the peak shifts to a lower temperature with an increase of the carbon content. And a comparison of the activation energy and the diffusion coefficient determined by internal friction methods with those measured in conventional macro-diffusion experiments reveals that the diffusion data measured by internal friction method and the diffusion data measured by conventional method exist in the same line. It follows from the above fact that observed internal friction peak is associated with the stress-induced diffusion of carbon in face-centered cubic alloys. (Author)

  9. Assessments of internal doses by ingestion of radioactive foodstuffs in Bangladesh

    International Nuclear Information System (INIS)

    Mollah, A.S.

    1996-01-01

    The internal radiation dose to a man from the consumption of foodstuffs was estimated an the basis of the measured radioactivities in the foodstuffs in Bangladesh. The total annual internal effective dose equivalent was found to be 454.56 μSv. The dose from intake of radionuclides by foodstuffs (ingestion dose) in general is so low that no harmful effects will occur directly. (author)

  10. The models of internal dose calculation in ICRP

    International Nuclear Information System (INIS)

    Nakano, Takashi

    1995-01-01

    There are a lot discussions about internal dose calculation in ICRP. Many efforts are devoted to improvement in models and parameters. In this report, we discuss what kind of models and parameters are used in ICRP. Models are divided into two parts, the dosimetric model and biokinetic model. The former is a mathematical phantom model, and it is mainly developed in ORNL. The results are used in many researchers. The latter is a compartment model and it has a difficulty to decide the parameter values. They are not easy to estimate because of their age dependency. ICRP officially sets values at ages of 3 month, 1 year, 5 year, 10 year, 15 year and adult, and recommends to get values among ages by linear age interpolate. But it is very difficult to solve the basic equation with these values, so we calculate by use of computers. However, it has complex shame and needs long CPU time. We should make approximated equations. The parameter values include much uncertainty because of less experimental data, especially for a child. And these models and parameter values are for Caucasian. We should inquire whether they could correctly describe other than Caucasian. The body size affects the values of calculated SAF, and the differences of metabolism change the biokinetic pattern. (author)

  11. Research on compliance coefficient calculation for heterogeneity material bolted joints of reactor internal

    International Nuclear Information System (INIS)

    Li Qing; Ren Xin; Zhang Kangda

    2009-01-01

    Using the finite element method, calculation and test are conducted on the bolted joints of four different diameters, and the existing calculation method for bolt compliance coefficient is analyzed. The results indicate that the calculated and test results by finite element method are agreed well, and value D/t f and β have a linear relation. (authors)

  12. Observation of changing of the internal conversion coefficient under Moessbauer effect at magnetic transition in Rh-Fe system

    International Nuclear Information System (INIS)

    Ruskov, T.

    1998-01-01

    The magnetic disorder-order transition in the Rh-Fe alloy is studied by conversion electron Moessbauer spectroscopy. The drastic increase of the area under the Moessbauer spectrum at the transition from the paramagnetic to the magnetic state could be explained by diminishing the internal conversion coefficient. Thus our experimental results directly confirm the theory of the collective effect in the system of radiating developed by Yukalov

  13. Estimation of internal heat transfer coefficients and detection of rib positions in gas turbine blades from transient surface temperature measurements

    International Nuclear Information System (INIS)

    Heidrich, P; Wolfersdorf, J v; Schmidt, S; Schnieder, M

    2008-01-01

    This paper describes a non-invasive, non-destructive, transient inverse measurement technique that allows one to determine internal heat transfer coefficients and rib positions of real gas turbine blades from outer surface temperature measurements after a sudden flow heating. The determination of internal heat transfer coefficients is important during the design process to adjust local heat transfer to spatial thermal load. The detection of rib positions is important during production to fulfill design and quality requirements. For the analysis the one-dimensional transient heat transfer problem inside of the turbine blade's wall was solved. This solution was combined with the Levenberg-Marquardt method to estimate the unknown boundary condition by an inverse technique. The method was tested with artificial data to determine uncertainties with positive results. Then experimental testing with a reference model was carried out. Based on the results, it is concluded that the presented inverse technique could be used to determine internal heat transfer coefficients and to detect rib positions of real turbine blades.

  14. True dose from incorporated activities. Models for internal dosimetry

    International Nuclear Information System (INIS)

    Breustedt, B.; Eschner, W.; Nosske, D.

    2012-01-01

    The assessment of doses after incorporation of radionuclides cannot use direct measurements of the doses, as for example dosimetry in external radiation fields. The only observables are activities in the body or in excretions. Models are used to calculate the doses based on the measured activities. The incorporated activities and the resulting doses can vary by more than seven orders of magnitude between occupational and medical exposures. Nevertheless the models and calculations applied in both cases are similar. Since the models for the different applications have been developed independently by ICRP and MIRD different terminologies have been used. A unified terminology is being developed. (orig.)

  15. The work of Committee 2 of ICRP in developing dose coefficients for the embryo and fetus following intakes of radionuclides by the mother

    International Nuclear Information System (INIS)

    Stather, J.W.; Phipps, A.W.

    1999-01-01

    Committee 2 of the International Commission on Radiological Protection has the responsibility for calculating radiation doses from intakes of radionuclides for all age groups in the population. This includes the development of models for calculating doses to the embryo and fetus following intakes of radionuclides by the mother. The development of both biokinetic and dosimetric models are reviewed and the results of preliminary dose calculations presented. (orig.) [de

  16. Estimates of external dose-rate conversion factors and internal dose conversion factors for selected radionuclides released from fusion facilities

    Energy Technology Data Exchange (ETDEWEB)

    Homma, Toshimitsu; Togawa, Orihiko [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1996-11-01

    This report provides a tabulation of both external dose-rate conversion factors and internal dose conversion factors using radioactive decay data in the updated Evaluated Nuclear Structure Data File (ENSDF) for selected 26 radionuclides and all their daughter radionuclides of potential importance in safety assessments of fusion facilities. The external dose-rate conversion factors for 21 target organs are tabulated for three exposure modes that are immersion in contaminated air, irradiation at a height of 1 m above a contaminated ground surface and immersion contaminated water. For internal exposure, committed dose equivalents, based on the methodology of ICRP Publication 30, in the same target organs per intake of unit activity are given for the inhalation and ingestion exposure pathways. The data presented here is intended to be generally used for safety assessments of fusion reactors. Comparisons of external effective dose-rate conversion factors and committed effective dose equivalents are made with the previous data from the independent data bases to provide quality assurance on our calculated results. There is generally good agreement among data from the independent data bases. The differences in the values of both effective dose-rate and dose conversion factors appeared are primarily due to differences in calculational methodology, the use of different radioactive decay data, and compilation errors. (author)

  17. Development of internal dose calculation programing via food ingestion

    International Nuclear Information System (INIS)

    Kim, H. J.; Lee, W. K.; Lee, M. S.

    1998-01-01

    Most of dose for public via ingestion pathway is calculating for considering several pathways; which start from radioactive material released from a nuclear power plant to diffusion and migration. But in order to model these complicate pathways mathematically, some assumptions are essential and lots of input data related with pathways are demanded. Since there is uncertainty related with environment in these assumptions and input data, the accuracy of dose calculating result is not reliable. To reduce, therefore, these uncertain assumptions and inputs, this paper presents exposure dose calculating method using the activity of environmental sample detected in any pathway. Application of dose calculation is aim at peoples around KORI nuclear power plant and the value that is used to dose conversion factor recommended in ICRP Publ. 60

  18. Measurement of secondary cosmic radiation and calculation of associated dose conversion coefficients for humans; Messung sekundaerer kosmischer Strahlung und Berechnung der zugehoerigen Dosiskonversionskoeffizienten fuer den Menschen

    Energy Technology Data Exchange (ETDEWEB)

    Simmer, Gregor

    2012-04-11

    Due to secondary cosmic radiation (SCR), pilots and flight attendants receive elevated effective doses at flight altitudes. For this reason, since 2003 aircrew members are considered as occupationally exposed, in Germany. This work deals with the calculation of dose conversion coefficients (DCC) for protons, neutrons, electrons, positrons, photons and myons, which are crucial for estimation of effective dose from SCR. For the first time, calculations were performed combining Geant4 - a Monte Carlo code developed at CERN - with the voxel phantoms for the reference female and male published in 2008 by ICRP and ICRU. Furthermore, measurements of neutron fluence spectra - which contribute the major part to the effective dose of SCR - were carried out at the Environmental Research Station Schneefernerhaus (UFS) located at 2650 m above sea level nearby the Zugspitze mountain, Germany. These measured neutron spectra, and additionally available calculated spectra, were then folded with the DCC calculated in this work, and effective dose rates for different heights were calculated.

  19. 10 CFR 20.1502 - Conditions requiring individual monitoring of external and internal occupational dose.

    Science.gov (United States)

    2010-01-01

    ... external and internal occupational dose. Each licensee shall monitor exposures to radiation and radioactive... 10 Energy 1 2010-01-01 2010-01-01 false Conditions requiring individual monitoring of external and internal occupational dose. 20.1502 Section 20.1502 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR...

  20. Monitoring and radiation dose estimation for internal contamination of occupational workers

    Energy Technology Data Exchange (ETDEWEB)

    Kol, R; Laichter, Y [Israel Atomic Energy Commission, Beersheba (Israel). Nuclear Research Center-Negev

    1996-12-01

    The assessment of interval radiation doses due to intake of radionuclides differs totally from external dosimetry. External dosimetry is relatively straight forward: Workers are equipped with appropriate dosimeters that give the dose upon direct reading. Internal dosimetry is actually an assessment of the dose based on results of personnel and environmental monitoring (authors).

  1. Rapid analysis of key radionuclides in urine and estimation of internal dose for nuclear accident emergency

    International Nuclear Information System (INIS)

    Zhao Shuquan; Hu Heping; Wu Mingyu; Zhu Guoying; Huang Shibin; Liu Shiming

    2005-01-01

    Objective: To estimate the internal doses of a Chinese visiting scholar in the Chernobyl accident. Methods: The contents of 134 Cs and 137 Cs in urine were measured using a Ge(Li) γ-spectrometer. Their internal doses were estimated according to ICRP reports. Dose review of 131I was performed referring to UNSCEAR 2000 report. Results: The effective dose equivalent from 134 Cs, 137 Cs and 131 I were 66 μSv, 88 μSv and 1728 μSv respectively. Their summation was 1.9 mSv. Conclusion: The internal dose from 131 I was 10 times higher than that from 134 Cs and 137 Cs. So, the earlier estimation of internal doses for 131 I is significant in evaluation on radiation injuries of a nuclear reactor accident. (authors)

  2. Considerations on absorbed dose estimates based on different β-dose point kernels in internal dosimetry

    International Nuclear Information System (INIS)

    Uchida, Isao; Yamada, Yasuhiko; Yamashita, Takashi; Okigaki, Shigeyasu; Oyamada, Hiyoshimaru; Ito, Akira.

    1995-01-01

    In radiotherapy with radiopharmaceuticals, more accurate estimates of the three-dimensional (3-D) distribution of absorbed dose is important in specifying the activity to be administered to patients to deliver a prescribed absorbed dose to target volumes without exceeding the toxicity limit of normal tissues in the body. A calculation algorithm for the purpose has already been developed by the authors. An accurate 3-D distribution of absorbed dose based on the algorithm is given by convolution of the 3-D dose matrix for a unit cubic voxel containing unit cumulated activity, which is obtained by transforming a dose point kernel into a 3-D cubic dose matrix, with the 3-D cumulated activity distribution given by the same voxel size. However, beta-dose point kernels affecting accurate estimates of the 3-D absorbed dose distribution have been different among the investigators. The purpose of this study is to elucidate how different beta-dose point kernels in water influence on the estimates of the absorbed dose distribution due to the dose point kernel convolution method by the authors. Computer simulations were performed using the MIRD thyroid and lung phantoms under assumption of uniform activity distribution of 32 P. Using beta-dose point kernels derived from Monte Carlo simulations (EGS-4 or ACCEPT computer code), the differences among their point kernels gave little differences for the mean and maximum absorbed dose estimates for the MIRD phantoms used. In the estimates of mean and maximum absorbed doses calculated using different cubic voxel sizes (4x4x4 mm and 8x8x8 mm) for the MIRD thyroid phantom, the maximum absorbed doses for the 4x4x4 mm-voxel were estimated approximately 7% greater than the cases of the 8x8x8 mm-voxel. They were found in every beta-dose point kernel used in this study. On the other hand, the percentage difference of the mean absorbed doses in the both voxel sizes for each beta-dose point kernel was less than approximately 0.6%. (author)

  3. Clinical application of a OneDose(TM) MOSFET for skin dose measurements during internal mammary chain irradiation with high dose rate brachytherapy in carcinoma of the breast

    International Nuclear Information System (INIS)

    Kinhikar, Rajesh A; Sharma, Pramod K; Tambe, Chandrashekhar M; Mahantshetty, Umesh M; Sarin, Rajiv; Deshpande, Deepak D; Shrivastava, Shyam K

    2006-01-01

    In our earlier study, we experimentally evaluated the characteristics of a newly designed metal oxide semiconductor field effect transistor (MOSFET) OneDose(TM) in-vivo dosimetry system for Ir-192 (380 keV) energy and the results were compared with thermoluminescent dosimeters (TLDs). We have now extended the same study to the clinical application of this MOSFET as an in-vivo dosimetry system. The MOSFET was used during high dose rate brachytherapy (HDRBT) of internal mammary chain (IMC) irradiation for a carcinoma of the breast. The aim of this study was to measure the skin dose during IMC irradiation with a MOSFET and a TLD and compare it with the calculated dose with a treatment planning system (TPS). The skin dose was measured for ten patients. All the patients' treatment was planned on a PLATO treatment planning system. TLD measurements were performed to compare the accuracy of the measured results from the MOSFET. The mean doses measured with the MOSFET and the TLD were identical (0.5392 Gy, 15.85% of the prescribed dose). The mean dose was overestimated by the TPS and was 0.5923 Gy (17.42% of the prescribed dose). The TPS overestimated the skin dose by 9% as verified by the MOSFET and TLD. The MOSFET provides adequate in-vivo dosimetry for HDRBT. Immediate readout after irradiation, small size, permanent storage of dose and ease of use make the MOSFET a viable alternative for TLDs. (note)

  4. Clinical application of a OneDose MOSFET for skin dose measurements during internal mammary chain irradiation with high dose rate brachytherapy in carcinoma of the breast.

    Science.gov (United States)

    Kinhikar, Rajesh A; Sharma, Pramod K; Tambe, Chandrashekhar M; Mahantshetty, Umesh M; Sarin, Rajiv; Deshpande, Deepak D; Shrivastava, Shyam K

    2006-07-21

    In our earlier study, we experimentally evaluated the characteristics of a newly designed metal oxide semiconductor field effect transistor (MOSFET) OneDose in-vivo dosimetry system for Ir-192 (380 keV) energy and the results were compared with thermoluminescent dosimeters (TLDs). We have now extended the same study to the clinical application of this MOSFET as an in-vivo dosimetry system. The MOSFET was used during high dose rate brachytherapy (HDRBT) of internal mammary chain (IMC) irradiation for a carcinoma of the breast. The aim of this study was to measure the skin dose during IMC irradiation with a MOSFET and a TLD and compare it with the calculated dose with a treatment planning system (TPS). The skin dose was measured for ten patients. All the patients' treatment was planned on a PLATO treatment planning system. TLD measurements were performed to compare the accuracy of the measured results from the MOSFET. The mean doses measured with the MOSFET and the TLD were identical (0.5392 Gy, 15.85% of the prescribed dose). The mean dose was overestimated by the TPS and was 0.5923 Gy (17.42% of the prescribed dose). The TPS overestimated the skin dose by 9% as verified by the MOSFET and TLD. The MOSFET provides adequate in-vivo dosimetry for HDRBT. Immediate readout after irradiation, small size, permanent storage of dose and ease of use make the MOSFET a viable alternative for TLDs.

  5. Fluence-to-effective dose conversion coefficients from a Saudi population based phantom for monoenergetic photon beams from 10 keV to 20 MeV

    International Nuclear Information System (INIS)

    Ma, Andy K; Hussein, Mohammed Adel; Altaher, Khalid Mohammed; Farid, Khalid Yousif; Amer, Mamun; Aldhafery, Bander Fuhaid; Alghamdi, Ali A

    2015-01-01

    Fluence-to-dose conversion coefficients are important quantities for radiation protection, derived from Monte Carlo simulations of the radiation particles through a stylised phantom or voxel based phantoms. The voxel phantoms have been developed for many ethnic groups for their accurate reflection of the anatomy. In this study, we used the Monte Carlo code MCNPX to calculate the photon fluence-to-effective dose conversion coefficients with a voxel phantom based on the Saudi Arabian male population. Six irradiation geometries, anterior–posterior (AP), posterior–anterior (PA), left lateral (LLAT), right lateral (RLAT), rotational (ROT) and isotropic (ISO) were simulated for monoenergetic photon beams from 10 keV to 20 MeV. We compared the coefficients with the reference values in ICRP Publication 116. The coefficients in the AP and PA geometries match the reference values to 9% and 12% on average as measured by root mean square while those in the LLAT, RLAT ROT and ISO geometries differ, mostly below, from the reference by 23, 22, 15 and 16%, respectively. The torso of the Saudi phantom is wider than the ICRP reference male phantom and likely to cause more attenuation to the lateral beam. The ICRP reference coefficients serve well for the Saudi male population as conservative estimations for the purpose of radiation protection. (paper)

  6. The Influence of Flexibility Coefficient on the Size of Internal Forces and Deformations in Circular Plates on Elastic Medium

    Directory of Open Access Journals (Sweden)

    Şandru Mirela

    2016-09-01

    Full Text Available This paper presents an analytical study which deals with the behavior of the circular plates in bending theory, considering the soil-structure interaction under Winkler's hypothesis. It was intended to illustrate the variation of internal forces and deformations according to the flexibility coefficient of plates considering three models: a fixed solid circular plate subjected to a uniformly distributed load, a fixed solid circular plate acted by a displacement applied on the exterior contour and a solid plate subjected to a temperature gradient. For this study the computation relations were written as a product between a dimensional and a non-dimensional factor, the last one indicating the variation of internal forces and deformations. For each type of action there are presented results obtained using the finite element method to illustrate the differences between this method and the analytical computation.

  7. Contribution of various of manufacturing of food products to internal exposure dose of population

    International Nuclear Information System (INIS)

    Bajrashevskaya, D.A.; Goncharova, N.V.

    2007-01-01

    Since 1986, considerable data have been produced and published on all the above aspects of the Cs 137 from soils to agricultural products. Today no critical evaluation of the available information has been undertaken. There is an obvious need to evaluate the relative importance of agricultural foodstuffs as a source of internal dose. The importance of food from different production systems to the internal dose from radiocaesium was investigated in selected study sites in Belarus. This work considers approaches and methods of internal exposure dose evaluation for citizens of radioactive contaminated territories consuming food products of radioactive contaminated forests. (authors)

  8. Determination of internal exposure doses of the personnel of uranium-mining company due to radon isotopes decay products

    International Nuclear Information System (INIS)

    Sevostyanov, V.N.

    2004-01-01

    This work carries out a determination of individual doses of internal exposure of the staff of the uranium-mining company in Kazakhstan due to radon decay products. The company extracts uranium by in-situ leaching. After leaching, uranium is sorbed from a solution in facilities where the staff is located. The state of three uranium mines was analyzed. The dose determination was conducted in tune with the proposed method by using integral alpha-tracking detectors to identify the content of 222 Rn and express appliances to identify the content of radio-active aerosols in air of the working area for determination the equilibrium coefficient. The measurements were performed within one year. The work produced the results in average annual values of radon and thoron decay products activity concentration and variation, equilibrium coefficient variation, and so-called expressive-to-integral value conversion factor. The obtained personnel's individual radiation doses due to radon exposure for this period lie within the range of < 1 mSv/year. (author)

  9. Internal transmission coefficient in charges carrier generation layer of graphene/Si based solar cell device

    International Nuclear Information System (INIS)

    Rosikhin, Ahmad; Winata, Toto

    2016-01-01

    Internal transmission profile in charges carrier generation layer of graphene/Si based solar cell has been explored theoretically. Photovoltaic device was constructed from graphene/Si heterojunction forming a multilayer stuck with Si as generation layer. The graphene/Si sheet was layered on ITO/glass wafer then coated by Al forming Ohmic contact with Si. Photon incident propagate from glass substrate to metal electrode and assumed that there is no transmission in Al layer. The wavelength range spectra used in this calculation was 200 – 1000 nm. It found that transmission intensity in the generation layer show non-linear behavior and partitioned by few areas which related with excitation process. According to this information, it may to optimize the photons absorption to create more excitation process by inserting appropriate material to enhance optical properties in certain wavelength spectra because of the exciton generation is strongly influenced by photon absorption.

  10. Fluence to absorbed foetal dose conversion coefficients for photons in 50 keV-10 GeV calculated using RPI-P models

    International Nuclear Information System (INIS)

    Taranenko, V.; Xu, X.G.

    2008-01-01

    Radiation protection of pregnant females and the foetus against ionising radiation is of particular importance to radiation protection due to high foetal radiosensitivity. The only available set of foetal conversion coefficients for photons is based on stylised models of simplified anatomy. Using the RPI-P series of pregnant female and foetus models representing 3-, 6- and 9-month gestation, a set of new fluence to absorbed foetal dose conversion coefficients has been calculated. The RPI-P anatomical models were developed using novel 3D geometry modelling techniques. Organ masses were adjusted to agree within 1% with the ICRP reference data for a pregnant female. Monte Carlo dose calculations were carried out using the MCNPX and Penelope codes for external 50 keV-10 GeV photon beams of six standard configurations. The models were voxelised at 3-mm voxel resolution. Conversion coefficients were tabulated for the three gestational periods for the whole foetus and brain. Comparison with previously published data showed deviations up to 120% for the foetal doses at 50 keV. The discrepancy can be primarily ascribed to anatomical differences. Comparison with published data for five major mother organs is also provided for the 3-month model. Since the RPI-P models exhibit a high degree of anatomical realism, the reported dataset is recommended as a reference for radiation protection of the foetus against external photon exposure. (authors)

  11. Transport Properties of Bulk Thermoelectrics—An International Round-Robin Study, Part I: Seebeck Coefficient and Electrical Resistivity

    Science.gov (United States)

    Wang, Hsin; Porter, Wallace D.; Böttner, Harald; König, Jan; Chen, Lidong; Bai, Shengqiang; Tritt, Terry M.; Mayolet, Alex; Senawiratne, Jayantha; Smith, Charlene; Harris, Fred; Gilbert, Patricia; Sharp, Jeff W.; Lo, Jason; Kleinke, Holger; Kiss, Laszlo

    2013-04-01

    Recent research and development of high-temperature thermoelectric materials has demonstrated great potential for converting automobile exhaust heat directly into electricity. Thermoelectrics based on classic bismuth telluride have also started to impact the automotive industry by enhancing air-conditioning efficiency and integrated cabin climate control. In addition to engineering challenges of making reliable and efficient devices to withstand thermal and mechanical cycling, the remaining issues in thermoelectric power generation and refrigeration are mostly materials related. The dimensionless figure of merit, ZT, still needs to be improved from the current value of 1.0 to 1.5 to above 2.0 to be competitive with other alternative technologies. In the meantime, the thermoelectric community could greatly benefit from the development of international test standards, improved test methods, and better characterization tools. Internationally, thermoelectrics have been recognized by many countries as a key component for improving energy efficiency. The International Energy Agency (IEA) group under the Implementing Agreement for Advanced Materials for Transportation (AMT) identified thermoelectric materials as an important area in 2009. This paper is part I of the international round-robin testing of transport properties of bulk thermoelectrics. The main foci in part I are the measurement of two electronic transport properties: Seebeck coefficient and electrical resistivity.

  12. Calculation of absorbed dose of anchorage-dependent cells from internal beta-rays irradiation

    International Nuclear Information System (INIS)

    Chen Jianwei; Huang Gang; Li Shijun

    2001-01-01

    Objective: To elicit the formula of internal dosimetry in anchorage-dependent cells by beta-emitting radionuclides from uniformly distributed volume sources. Methods: By means of the definition of absorbed dose and the MIRD (Medical International Radiation Dose) scheme the formula of internal dosimetry was reasonably deduced. Firstly, studying the systems of suspension culture cells. Then, taking account of the speciality of the systems of the anchorage-dependent cells and the directions of irradiation, the absorbed dose of anchorage -dependent cells was calculated by the accumulated radioactivity, beta-ray energy, and the volume of the cultured systems. Results: The formula of internal dosimetry of suspension culture cells and anchorage-dependent cells were achieved. At the same time, the formula of internal dosimetry of suspension culture cells was compared with that of MIRD and was confirmed accurate. Conclusion: The formula of internal dosimetry is concise, reliable and accurate

  13. Internal radiation doses from radioactivity of drinking water in Finland

    International Nuclear Information System (INIS)

    Kahlos, H.; Asikainen, M.

    1980-01-01

    A study of the radioactivity of drinking water in Finland was carried out from 1974 to 1978. Samples were collected from nearly all water supply plants with more than 200 users and from privately dug or drilled wells. This paper considers drinking water as a factor in increasing the natural radiation exposure of the population and estimates the collective and per capita dose rates caused by the 222 Rn present in water. Instead of performing dose calculations, the significance of 226 Ra and uranium is assessed by means of daily intake. The assessment is made for both the whole population and three subgroups using the water from water supply plants and privately dug or drilled wells. (author)

  14. Natural Radionuclides and 137Cs Concentrations in Rice in Jepara Residence and Internal Dose Estimation Intake by the People

    International Nuclear Information System (INIS)

    Leli-Nirwani; Minarni; Buchari

    2001-01-01

    The measurement of natural radionuclides and 137 Cs concentration in rice in Jepara residence and internal dose estimation intake by people have been conducted. The aim of the research is to determine internal dose estimation of natural radionuclides and 137 Cs intake by people in Jepara residence. By knowing the natural radionuclides and 137 Cs concentrations in rice at Jepara residence, the dose coefficient for adult from ICRP No.72 and the annual intake consumption take from the Indonesian food balance published by BPS, the internal dose from natural radionuclides and 137 Cs intake from food can be calculate concentration of 228 Th, 226 Ra and 137 Cs were found in Bayuran, with the average value was (2.00±0.21) x 10 -5 Bq/kg, (0.09±0.25) x 10 -5 Bq/kg, (19.00±0.06) x 10 -5 Bq/kg respectively the highest 40 K concentration was found in Pandansili with the average was about (8.40 ± 0.34) x 10 -5 Bq/kg. The estimation of equivalent doses from intake of 228 Th, 226 Ra, 40 K, and 137 Cs in rice were the highest in Bayuran the value the average values, respectively, was 0.0039 x 10 -5 μ Sv/yr, 18.09 X 10 -5 μ Sv/yr, 1.63 x 10 -5 μ Sv/yr, 172.38 x 10 -5 μ Sv/yr. Result in this measurement lowest comparing by recommendation IAEA in Safety Series No. 115 in 1996. (author)

  15. ARN Training Course on Advance Methods for Internal Dose Assessment: Application of Ideas Guidelines

    International Nuclear Information System (INIS)

    Rojo, A.M.; Gomez Parada, I.; Puerta Yepes, N.; Gossio, S.

    2010-01-01

    Dose assessment in case of internal exposure involves the estimation of committed effective dose based on the interpretation of bioassay measurement, and the assumptions of hypotheses on the characteristics of the radioactive material and the time pattern and the pathway of intake. The IDEAS Guidelines provide a method to harmonize dose evaluations using criteria and flow chart procedures to be followed step by step. The EURADOS Working Group 7 'Internal Dosimetry', in collaboration with IAEA and Czech Technical University (CTU) in Prague, promoted the 'EURADOS/IAEA Regional Training Course on Advanced Methods for Internal Dose Assessment: Application of IDEAS Guidelines' to broaden and encourage the use of IDEAS Guidelines, which took place in Prague (Czech Republic) from 2-6 February 2009. The ARN identified the relevance of this training and asked for a place for participating on this activity. After that, the first training course in Argentina took place from 24-28 August for training local internal dosimetry experts. (authors)

  16. Determination of dose to patient in different teams of TC and assessment with international reference levels

    International Nuclear Information System (INIS)

    Ruiz Morales, C.; Fernandez lara, A. A.; Buades Forner, M. J.; Tobarra Gonzalez, B. M.

    2013-01-01

    The increase in CT studies and the differences observed between the different equipment used in our hospital prompted us to determine the doses to patients in different studies and check the results obtained with the reference values published internationally. (Author)

  17. Fluence to Effective Dose and Effective Dose Equivalent Conversion Coefficients for Photons from 50 KeV to 10 GeV

    International Nuclear Information System (INIS)

    Ferrari, A.; Pelliccioni, M.; Pillon, M.

    1996-07-01

    Effective dose equivalent and effective dose per unit photon fluence have been calculated by the FLUKA code for various geometrical conditions of irradiation of an anthropomorphic phantom placed in a vacuum. Calculations have been performed for monoenergetic photons of energy ranging from 50 keV to 10 GeV. The agreement with the results of other authors, when existing, is generally very satisfactory

  18. Dose control for internal radiation; Kawalan dos untuk sinaran dalam

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1988-12-31

    The chapter briefly discussed the following subjects: aerosol physics, relationship of surface contamination and internal contamination for workers, surface contamination control and the it`s procedures i.e. protective personnel cloth, waste management in active area, storage of radioactive materials etc.

  19. Internal dose evaluation of workers involved in radioisotopes and radiopharmaceuticals handling for medical use

    International Nuclear Information System (INIS)

    Cesar, R.B.P.; Mesquita, C.H. de

    1987-01-01

    The internal dose levels of IPEN workers, involved in the production of radioisotopes and radiopharmaceuticals for medical use are surveyed. In this production, the workers were splited in six group: research and development, routine production, quality control, packaging, radiological protection and maintenance. The internal dose was evaluated according to the models described by ICRP-30, from the results obtained in the whole body counters monitoring. (C.G.C.) [pt

  20. Field and Bioassay Indicators for Internal Dose Intervention Therapy

    International Nuclear Information System (INIS)

    Carbaugh, Eugene H.

    2007-01-01

    Guidance is presented that is used at the U.S. Department of Energy Hanford Site to identify the potential need for medical intervention in response to intakes of radioactivity. The guidance, based on ICRP Publication 30 models and committed effective dose equivalents of 20 mSv and 200 mSv, is expressed as numerical workplace measurements and derived first-day bioassay results for large intakes. It is used by facility radiation protection staff and on-call dosimetry support staff during the first few days following an intake

  1. Second Latin American intercomparison on internal dose assessment

    International Nuclear Information System (INIS)

    Rojo, A.; Puerta, N.; Gossio, S.; Gomez Parada, I.; Cruz Suarez, R.; Lopez, E.; Medina, C.; Lastra Boylan, J.; Pinheiro Ramos, M.; Mora Ramirez, E.; Alves dos Reis, A.; Yanez, H.; Rubio, J.; Vironneau Janicek, L.; Somarriba Vanegas, F.; Puerta Ortiz, J.; Salas Ramirez, M.; Lopez Bejerano, G.; Da Silva, T.; Miri Oliveira, C.; Teran, M.; Alfaro, M.; Garcia, T.; Angeles, A.; Dure Romero, E.; Farias de Lima, F.

    2016-01-01

    Internal dosimetry intercomparisons are essential for the verification of applied models and the consistency of results. To that aim, the First Regional Intercomparison was organised in 2005, and that results led to the Second Regional Intercomparison Exercise in 2013, which was organised in the frame of the RLA 9/066 and coordinated by Autoridad Regulatoria Nuclear of Argentina. Four simulated cases covering intakes of 131 I, 137 Cs and Tritium were proposed. Nineteen centres from thirteen different countries participated in this exercise. This paper analyses the participants' results in this second exercise in order to test their skills and acquired knowledge, particularly in the application of the IDEAS Guidelines. It is important to highlight the increased number of countries that participated in this exercise compared with the first one and, furthermore, the improvement in the overall performance. The impact of the International Atomic Energy Agency (IAEA) Projects since 2003 has led to a significant enhancement of internal dosimetry capabilities that strengthen the radiation protection of workers. (authors)

  2. SECOND LATIN AMERICAN INTERCOMPARISON ON INTERNAL DOSE ASSESSMENT.

    Science.gov (United States)

    Rojo, A; Puerta, N; Gossio, S; Gómez Parada, I; Cruz Suarez, R; López, E; Medina, C; Lastra Boylan, J; Pinheiro Ramos, M; Mora Ramírez, E; Alves Dos Reis, A; Yánez, H; Rubio, J; Vironneau Janicek, L; Somarriba Vanegas, F; Puerta Ortiz, J; Salas Ramírez, M; López Bejerano, G; da Silva, T; Miri Oliveira, C; Terán, M; Alfaro, M; García, T; Angeles, A; Duré Romero, E; Farias de Lima, F

    2016-09-01

    Internal dosimetry intercomparisons are essential for the verification of applied models and the consistency of results'. To that aim, the First Regional Intercomparison was organised in 2005, and that results led to the Second Regional Intercomparison Exercise in 2013, which was organised in the frame of the RLA 9/066 and coordinated by Autoridad Regulatoria Nuclear of Argentina. Four simulated cases covering intakes of (131)I, (137)Cs and Tritium were proposed. Ninteen centres from thirteen different countries participated in this exercise. This paper analyses the participants' results in this second exercise in order to test their skills and acquired knowledge, particularly in the application of the IDEAS Guidelines. It is important to highlight the increased number of countries that participated in this exercise compared with the first one and, furthermore, the improvement in the overall performance. The impact of the International Atomic Energy Agency (IAEA) Projects since 2003 has led to a significant enhancement of internal dosimetry capabilities that strengthen the radiation protection of workers. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. Doses from radiation exposure

    International Nuclear Information System (INIS)

    Menzel, H-G.; Harrison, J.D.

    2012-01-01

    Practical implementation of the International Commission on Radiological Protection’s (ICRP) system of protection requires the availability of appropriate methods and data. The work of Committee 2 is concerned with the development of reference data and methods for the assessment of internal and external radiation exposure of workers and members of the public. This involves the development of reference biokinetic and dosimetric models, reference anatomical models of the human body, and reference anatomical and physiological data. Following ICRP’s 2007 Recommendations, Committee 2 has focused on the provision of new reference dose coefficients for external and internal exposure. As well as specifying changes to the radiation and tissue weighting factors used in the calculation of protection quantities, the 2007 Recommendations introduced the use of reference anatomical phantoms based on medical imaging data, requiring explicit sex averaging of male and female organ-equivalent doses in the calculation of effective dose. In preparation for the calculation of new dose coefficients, Committee 2 and its task groups have provided updated nuclear decay data (ICRP Publication 107) and adult reference computational phantoms (ICRP Publication 110). New dose coefficients for external exposures of workers are complete (ICRP Publication 116), and work is in progress on a series of reports on internal dose coefficients to workers from inhaled and ingested radionuclides. Reference phantoms for children will also be provided and used in the calculation of dose coefficients for public exposures. Committee 2 also has task groups on exposures to radiation in space and on the use of effective dose.

  4. Rural settlements: social and ecological factors influencing on internal dose formation

    International Nuclear Information System (INIS)

    Visenberg, Yu.V; Vlasova, N.G.

    2008-01-01

    Full text: The aim of the present study is to reveal the reasons of difference in average internal doses in rural population living in the rural settlements situated on territories with equal levels of soil contamination; to show by clear examples that forming of internal dose is not only influenced directly by the contamination of the territory but also by number of factors of non-radiation origin. There were used data on internal doses as a result of WBC-measurements in rural inhabitants. Method of the study: there was applied the statistical analysis of the internal dose in rural population depending on the number of factors: radio-ecological represented by the transfer factor of radionuclides from soil to milk; environmental - closeness to the forest which, in its turn, determines intake of its resources by rural population; social - the number of population. There were selected settlements for the investigation whose residents had been WBC-measured for the period of 1990-2005's and their doses were evaluated. Thus, the conducted analysis shows that each of indirect (non-radiation) factors contributes in different way into formation of internal dose. The most significant of them is the social factor as follows from the results of the conducted analysis, represented by the number of inhabitants in a settlement. The internal dose depends not only on the level of contamination of the territory but also on the number of other factors: environmental, social, and radio-ecological. The influence of these factors on the process of dose formation in settlements should be considered simultaneously since neither of them is the leading one. Probably, there are other factors influencing on dose formation. Their investigation must be continued. (author)

  5. Internal conversion coefficients of M4 isomeric transitions in /sup 125/ /sup 127/ /sup 129/Te decay

    Energy Technology Data Exchange (ETDEWEB)

    Soni, S K; Kumar, A; Gupta, S L; Pancholi, S C [Delhi Univ. (India). Dept. of Physics and Astrophysics

    1977-01-01

    The internal conversion coefficients have been measured using a high resolution low energy Ge(Li) detector for the following M4 transitions: /sup 125/Te: 109.27 keV transition ..cap alpha..sub(T) = 357 +- 11; RG method, /sup 127/Te: 88,26 keV transition ..cap alpha..sub(K) = 484 +- 23; XPG method, /sup 129/Te: 105.50 keV transition ..cap alpha..sub(K) = 213 +- 10; XPG method. It is observed that these values are lower by 2.5-3.6% as compared with Hager and Seltzer's calculations. A comparison between experimental and theoretical ..cap alpha..sub(K) and ..cap alpha..sub(T) values for eleven M4 transitions shows that the experimental values are systematically lower.

  6. Mathematical phantoms for evaluation of age-specific internal dose

    International Nuclear Information System (INIS)

    Cristy, M.

    1980-01-01

    A series of mathematical phantoms representing children has been developed for use with photon transport codes. These phantoms, patterned after the Fisher-Snyder adult phantom, consist of simple mathematical expressions for the boundaries of the major organs and body sections. The location and shape of the organs are consistent with drawings depicting developmental anatomy, with the organ volumes assigned such that the masses at the various ages conform closely with the data presented in Reference Man. The explicit mathematical expressions for the various ages overcome the potential misrepresentation of organ sizes that occurred in phantoms derived from simple mathematical transformations of the adult phantom. Female breast tissue has been added to the phantoms, including the adult, now allowing assessment of doses to this organ

  7. Internal dose from tritium at Wolsung nuclear power plant

    International Nuclear Information System (INIS)

    Hee Geun Kim; Jeong Yull Dho; Myung Jae Song

    1995-01-01

    Tritium is produced in large quantities at heavy water nuclear power reactors via the neutron activation reaction 2 H(n,γ) 3 H. At Wolsung nuclear power plant which has a CANDU reactor, the tritium concentrations in coolant and in moderator systems are 1.5 Ci/Kg-D 2 O and 35 Ci/kg-D 2 O, respectively, after 12 years of operation. The airborne tritium concentration in main access area is normally less than 5 MPCa except short-term peaks. The average tritium concentrations in main access controlled areas are normally less than 100 MPCa. Tritium is mainly present in the air of workplace of CANDU reactors as a tritiated water vapour. Airborne tritiated water vapour enters the workers body via inhalation and absorption through skin and can result in a significant dose. The occupational doses from tritium at Wolsung NPP have been maintained below 1 man-Sv per year so far. The tritium contribution to the total plant man-Sv changes between 30 percent and 50 percent. For the mitigation of tritium inhalation, various protective equipment are being used at Wolsung NPP. The respirator system was devised at Wolsung NPP in order to remove tritiated water vapours from the inhaled air. A respirator is connected to a small plastic bottle filled with ice cubes. The system devised shows a good tritium removal efficiency. The air pressure drop through the ice cubes is minimal. The operation cost of the system is also very cheap. Further mitigation of tritium inhalation is heavily dependant on the source term reduction. One of the ultimate solutions is to introduce a tritium removal facility. (author). 7 figs., 3 tabs

  8. The effective dose equivalent from external and internal radiation

    International Nuclear Information System (INIS)

    Mattsson, Soeren

    1989-01-01

    The various sources of low-level ionizing radiation are discussed and compared in terms of mean effective dose equivalent to man. For the most nonoccupationally exposed individuals, natural sources given the dominating contribution to the effective dose equivalent. The size of this contribution is strongly dependent on human activities. Natural sources contribution on average 2.4 mSV per year, of which half is due to irradiation of lungs and airways from short lived radon daughters present in indoor air. In Sweden this radon daughter contribution is considerably higher and contributes a mean of 3 mSv per year, thus giving a total contribution from natural radiation of about 4 mSV per year. In extreme cases, radon daughter contributions of several hundreds of mSv per year may be reached. Medical exposure, mainly diagnostic X-rays, contributes 0.4-1 mSv per year both in Sweden and as a world average. The testing of nuclear weapons in the atmosphere has given 1-2 mSv to each person in the world as a mean. The contribution from the routine operation of nuclear reactors is insignificant. The reactor accident in Chernobyl resulted in widely varying exposures of the European population. The average for Sweden is estimated to be 0.1 mSv during the first year and about 1 mSv during a 50-year period. For groups of Swedes who eat a considerable amount of game this contribution will be 10 times higher, and for the Lapps who breed reindeer in the most contaminated areas, typical values of 20-70 mSv and extreme values of about 1 Sv may be reached in 50 years. This means that the Chernobyl reactor accident for several years will be their dominating source of irradiation

  9. A comparison of simple and realistic eye models for calculation of fluence to dose conversion coefficients in a broad parallel beam incident of protons

    International Nuclear Information System (INIS)

    Sakhaee, Mahmoud; Vejdani-Noghreiyan, Alireza; Ebrahimi-Khankook, Atiyeh

    2015-01-01

    Radiation induced cataract has been demonstrated among people who are exposed to ionizing radiation. To evaluate the deterministic effects of ionizing radiation on the eye lens, several papers dealing with the eye lens dose have been published. ICRP Publication 103 states that the lens of the eye may be more radiosensitive than previously considered. Detailed investigation of the response of the lens showed that there are strong differences in sensitivity to ionizing radiation exposure with respect to cataract induction among the tissues of the lens of the eye. This motivated several groups to look deeper into issue of the dose to a sensitive cell population within the lens, especially for radiations with low energy penetrability that have steep dose gradients inside the lens. Two sophisticated mathematical models of the eye including the inner structure have been designed for the accurate dose estimation in recent years. This study focuses on the calculations of the absorbed doses of different parts of the eye using the stylized models located in UF-ORNL phantom and comparison with the data calculated with the reference computational phantom in a broad parallel beam incident of protons with energies between 20 MeV and 10 GeV. The obtained results indicate that the total lens absorbed doses of reference phantom has good compliance with those of the more sensitive regions of stylized models. However, total eye absorbed dose of these models greatly differ with each other for lower energies. - Highlights: • The validation of reference data for the eye was studied for proton exposures. • Two real mathematical models of the eye were imported into the UF-ORNL phantom. • Fluence to dose conversion coefficients were calculated for different eye sections. • Obtained Results were compared with that of assessed by ICRP adult male phantom

  10. Internal dose assessment in nuclear medicine: fetal doses due to radiopharmaceutical administration to the mother

    International Nuclear Information System (INIS)

    Rojo, Ana M.; Michelin, Severino C.

    2004-01-01

    The objective of this publication is to present a guideline for the dose assessment through a comprehensive introduction of knowledge on ionizing radiation, radiation protection during pregnancy and fetal dosimetry for physician and other professionals involved in nuclear medicine practices. It contains tables with recommended dose estimates at all stages of pregnancy for many radiopharmaceuticals. Compounds for which some information was available regarding placental crossover are shown in shaded rows. It includes the most common diagnostic and therapy practices in nuclear medicine considering the four radioactive isotopes selected: 99m Tc, 131 I, 201 Tl and 67 Ga. There is a special case included, it is when conception occurs after the iodine has been administered. In almost every case, the diagnostic benefit to the mother outweighs the risk of any irradiation of the fetus. However, there is one situation in which severe fetal injury can be incurred from administering a radiopharmaceutical to the mother, and that is use of iodine-131 therapy for ablation of the thyroid in cases of hyperthyroidism or carcinoma. Radioactive iodine readily crosses the placenta and concentrates in the fetal thyroid, where, because of its small organ mass, high radiation doses are received. (author)

  11. Development of Internal Dose Assessment Program for Nuclear Power Plant Employees

    Energy Technology Data Exchange (ETDEWEB)

    Song, Myung Jae; Kang, Duck Won; Maeng, Sung Jun; Kim, Hee Geun; Son, Soon Whan; Lim, Young Kee; Son, Joong Kwon; Park, Keyoung Rock [Korea Electric Power Research Institute, Taejon (Korea, Republic of); Jang, See Young; Ha, Jong Woo; Suh, Keyoung Won [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of); Oh, Oak Doo; Lee, Joong Woo; Yoon, Sung Sik [Yonsei University, Seoul (Korea, Republic of)

    1996-12-31

    Internal exposure monitoring based on new concept of radiation protection. Analysis and Performance test of the in vivo systems being operated in nuclear power plants in Korea. Design and fabrication of humanoid phantom for calibration of in vivo system. Development of internal dose evaluation code based on the ICRP 30 dosimetric model. (author). 44 refs., figs.

  12. A comparison of Australian and Canadian calibration coefficients for air kerma and absorbed dose to water for 60Co gamma radiation.

    Science.gov (United States)

    Shortt, K R; Huntley, R B; Kotler, L H; Boas, J F; Webb, D V

    2006-06-01

    Australian and Canadian calibration coefficients for air kerma and absorbed dose to water for 60Co gamma radiation have been compared using transfer standard ionization chambers of types NE 2561 and NE 2611A. Whilst the primary standards of air kerma are similar, both being thick-walled graphite cavity chambers but employing different methods to evaluate the Awall correction, the primary standards of absorbed dose to water are quite different. The Australian standard is based on measurements made with a graphite calorimeter, whereas the Canadian standard uses a sealed water calorimeter. The comparison result, expressed as a ratio of calibration coefficients R=N(ARPANSA)/N(NRC), is 1.0006 with a combined standard uncertainty of 0.35% for the air kerma standards and 1.0052 with a combined standard uncertainty of 0.47% for the absorbed dose to water standards. This demonstrates the agreement of the Australian and Canadian radiation dosimetry standards. The results are also consistent with independent comparisons of each laboratory with the BIPM reference standards. A 'trilateral' analysis confirms the present determination of the relationship between the standards, within the 0.09% random component of the combined standard uncertainty for the three comparisons.

  13. The role of a family for internal dose formation in rural community

    International Nuclear Information System (INIS)

    Vlasova, N.V.; Rozhko, A.V.; Stavrov, V.V.

    2008-01-01

    Full text: Despite correct evaluation of agricultural land contamination of a settlement and the activity of foodstuffs, it is impossible to explain dose formation in rural community. And without this knowledge it is impossible to estimate correctly decision-making. The dose formation research was provided earlier in rural community based on the concept describing that the individual with his personal characteristics, social and economic statuses during his practical activity interacting with the contaminated environment, actively contributes to dose formation. Such approach only partly allows revealing dose formation mechanisms though there are some unclear issues: for example, high doses at some children. At the same time children, as well as all residents are the members of families. Direct consumption of food stuffs is provided within a family. It is preceded with the formation of psycho-emotional perception of radiation danger factor. There have been used the data of internal doses of the inhabitants obtained by the results of WBC-measurements. Simultaneously with performing of WBC measurements by interviewing of adult members of a family there was revealed the frequency of visits to forest and consumption rate of its 'gifts'. The method of a family analysis of internal dose formation is the classification of families by set of the informative attributes describing dose formation in a family such as an average internal dose at a member of a family; family total dose; the description of a family 'contact' with a forest; the number of family members; the number of children in a family; average age and the educational level of adult members of a family; gender and occupation of the head of a family; age and education of the head of a family. As a result of multivariate classification of families in the settlement there was obtained 10 different classes providing complete imagination about a variety of families' types. The average doses in classes essentially

  14. Internal dosimetry performing dose assessments via bioassay measurements

    International Nuclear Information System (INIS)

    Bailey, K.M.

    1993-01-01

    The Internal Dosimetry Department at the Y-12 Plant maintains a state-of-the-art bioassay program managed under the guidance and regulations of the Department of Energy. The two major bioassay techniques currently used at Y-12 are the in vitro (urinalysis) and in vivo (lung counting) programs. Fecal analysis (as part of the in vitro program) is another alternative; however, since both urine and fecal analysis provide essentially the same capabilities for detecting exposures to uranium, the urinalysis is the main choice primarily for aesthetic reasons. The bioassay frequency is based on meeting NCRP 87 objectives which are to monitor the accumulation of radioactive material in exposed individuals, and to ensure that significant depositions are detected

  15. Control of internal exposure doses of Belarus population

    International Nuclear Information System (INIS)

    Minenko, V.; Drozdovich, V.; Ulanovski, A.; Ternov, V.I.; Vasilyeva, I.

    1997-01-01

    Starting from May 1986 instrumental control of internal exposure is being carried out in Belarus using different equipment. In earlier, iodine period, the basic aim of the control was a mass screening of the population for defining of iodine content in thyroid. After the iodine period attention of the radiological control was focused on monitoring of caesium radionuclides content in human bodies of the inhabitants of radioactively contaminated territories. Goals of the control were changing, depending on the time that passed since the day of the accident. Nowadays the National Commission of Belarus recognizes entering of the, Republic into rehabilitation period of the accident of the Chernobyl Nuclear Power Plant. Developed Conception of Protection Measures for the rehabilitation period for the population living at the territories affected by the radioactive contamination in the result of the Chernobyl catastrophe

  16. A review of the uncertainties in internal radiation dose assessment for inhaled thorium

    International Nuclear Information System (INIS)

    Hewson, G.S.

    1989-01-01

    Present assessments of internal radiation dose to designated radiation workers in the mineral sands industry, calculated using ICRP 26/30 methodology and data, indicate that some workers approach and exceed statutory radiation dose limits. Such exposures are indicative of the need for a critical assessment of work and operational procedures and also of metabolic and dosimetric models used to estimate internal dose. This paper reviews past occupational exposure experience with inhaled thorium compounds, examines uncertainties in the underlying radiation protection models, and indicates the effect of alternative assumptions on the calculation of committed effective dose equivalent. The extremely low recommended inhalation limits for thorium in air do not appear to be well supported by studies on the health status of former thorium refinery workers who were exposed to thorium well in excess of presently accepted limits. The effect of cautious model assumptions is shown to result in internal dose assessments that could be up to an order of magnitude too high. It is concluded that the effect of such uncertainty constrains the usefulness of internal dose estimates as a reliable indicator of actual health risk. 26 refs., 5 figs., 3 tabs

  17. Recommended values for the distribution coefficient (Kd) to be used in dose assessments for decommissioning the Zion Nuclear Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, T. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2014-09-24

    ZionSolutions is in the process of decommissioning the Zion Nuclear Power Plant. The site contains two reactor Containment Buildings, a Fuel Building, an Auxiliary Building, and a Turbine Building that may be contaminated. The current decommissioning plan involves removing all above grade structures to a depth of 3 feet below grade. The remaining underground structures will be backfilled. The remaining underground structures will contain low amounts of residual licensed radioactive material. An important component of the decommissioning process is the demonstration that any remaining activity will not cause a hypothetical individual to receive a dose in excess of 25 mrem/y as specified in 10CFR20 SubpartE.

  18. Recommended values for the distribution coefficient (Kd) to be used in dose assessments for decommissioning the Zion Nuclear Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan T.

    2014-06-09

    ZionSolutions is in the process of decommissioning the Zion Nuclear Power Plant. The site contains two reactor Containment Buildings, a Fuel Building, an Auxiliary Building, and a Turbine Building that may be contaminated. The current decommissioning plan involves removing all above grade structures to a depth of 3 feet below grade. The remaining underground structures will be backfilled. The remaining underground structures will contain low amounts of residual licensed radioactive material. An important component of the decommissioning process is the demonstration that any remaining activity will not cause a hypothetical individual to receive a dose in excess of 25 mrem/y as specified in 10CFR20 SubpartE.

  19. Accuracy of internal dose calculations with special consideration of radiopharmaceutical biokinetics

    International Nuclear Information System (INIS)

    Roedler, H.D.

    1981-01-01

    The individual steps of internal dose calculation, including the models and data used, as well as error considerations, are analysed following a short synopsis on the formalism of absorbed dose calculation. The mean dose in a target tissue depends on the administered activity, the residence time of the activity in the source tissues and the mean absorbed dose in the target tissue per transformation in a source tissue. Usually, a standard dosage is applied in radionuclide studies except in children. Actually administered and nomial activities generally differ by less than 10%. For the purpose of internal dose calculation, the biokinetics of a radiopharmaceutical are reflected in the residence times for the individual source tissues. The methods and the evaluation of measurements of biodistribution and retention data are discussed. The extrapolation of animal data to man is treated in some detail, including a survey of the methods used, as well as an attempt for validating these methods. None of these seem to yield more convincing results than the direct transfer of the residence times from animal to man, at least for the two radiopharmaceuticals discussed. The minimum period of measurement to derive residence times for the purpose of dose calculation has been determined as about one physical half-time. Some problems of the dose per transformation to a phantom are presented, including the age- or size-dependence of the internal dose. Organ doses to the phantom, calculated from different apparently reliable sets of biokinetic data, are generally compatible within a factor of 2 to 3, and somatically effective doses are generally compatible within a factor of less than 2

  20. Development of an effective dose coefficient database using a computational human phantom and Monte Carlo simulations to evaluate exposure dose for the usage of NORM-added consumer products.

    Science.gov (United States)

    Yoo, Do Hyeon; Shin, Wook-Geun; Lee, Jaekook; Yeom, Yeon Soo; Kim, Chan Hyeong; Chang, Byung-Uck; Min, Chul Hee

    2017-11-01

    After the Fukushima accident in Japan, the Korean Government implemented the "Act on Protective Action Guidelines Against Radiation in the Natural Environment" to regulate unnecessary radiation exposure to the public. However, despite the law which came into effect in July 2012, an appropriate method to evaluate the equivalent and effective doses from naturally occurring radioactive material (NORM) in consumer products is not available. The aim of the present study is to develop and validate an effective dose coefficient database enabling the simple and correct evaluation of the effective dose due to the usage of NORM-added consumer products. To construct the database, we used a skin source method with a computational human phantom and Monte Carlo (MC) simulation. For the validation, the effective dose was compared between the database using interpolation method and the original MC method. Our result showed a similar equivalent dose across the 26 organs and a corresponding average dose between the database and the MC calculations of database with sufficient accuracy. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. First Italian intercomparison on methodologies for dose assessment from internal contamination. Results and perspectives

    International Nuclear Information System (INIS)

    Castellani, C.M.; Battisti, P.; Tarroni, G.

    1998-01-01

    In the frame of the MIDIA activities (coordination of whole body counters operating in Italy) an intercomparison on dose evaluation methods was promoted and carried out between October 1995 and March 1996 by 5 WBC centres. The main results related to the estimation of Intake and effective dose equivalent on the four case studies are reported. A comparison with European preliminary results is also presented. Finally perspectives related to the quality assurance of internal dosimetry estimates are indicated [it

  2. An approach to routine individual internal dose monitoring at the object 'Shelter' personnel considering uncertainties

    International Nuclear Information System (INIS)

    Mel'nichuk, D.V.; Bondarenko, O.O.; Medvedjev, S.Yu.

    2002-01-01

    An approach to organisation of routine individual internal dose monitoring of the personnel of the Object 'Shelter' is presented in the work, that considers individualised uncertainties. In this aspect two methods of effective dose assessment based on bioassay are considered in the work: (1) traditional indirect method at which application results of workplace monitoring are not taken into account, and (2) a combined method in which both results of bioassay measurements and workplace monitoring are considered

  3. Basic evaluation of signal transmission in a real-time internal radiation dose measurement system

    International Nuclear Information System (INIS)

    Shinohe, K.; Takura, T.; Sato, F.; Matsuki, H.; Yamada, S.; Sato, T.

    2009-01-01

    In radiation therapy, excessive exposure to radiation occurs because the dose actually delivered to the tumor is not known. As a result, a patient suffers from side effects. To solve this problem, a system is needed in which the delivered dose is measured inside the body and the dose data are transmitted from inside to outside of the body during radiation therapy. If such a system is realized, it will be possible to treat cancer safely and effectively. The proposed real-time internal radiation dose measurement system consists of an implantable dosimeter, a wireless communication system, and a wireless feeding system. In this study, a wireless communication system that uses magnetic fields was investigated. As a result, a communication distance of 200 mm was obtained. It was confirmed that radiation dose data could be transmitted outside the body when the communication distance is the required 200 mm. (author)

  4. Method for internal conversion coefficients determination by means of a magnetic spectrometer. Application to 129Xe and 77Se

    International Nuclear Information System (INIS)

    Arqueros, F.; Campos, J.

    1986-01-01

    The method used for efficiency calibration of a magnetic electron spectrometer and its applications to conversion electron spectrometry is described. The present results point out that apparatus combining magnetic deflection and semiconductor detection have a nondecreasing interest in nuclear spectrometry for applications where good resolution and large background rejection are both necessary. The present apparatus can be employed with source of relatively low activity, (0.lμCi). The nuclides studied were 129 Xe and 77 Se resulting from 129 Cs and 77 Br decay. The parent nulcides were produced in ISOLDE on line isotope separator at CERN. The efficiency calibration method used for energies higher than 200 keV made use of the well known beta spectrum of 36 Cl. The calibration for low energies was made with Auger electron intensities and suitable conversion lines of 129 Xenon. Results for relative intensities of conversion electron lines and intense gamma lines of 129 Xe and 77 Se are given. From these measurements internal conversion coefficients for transitions of both nuclides were obtained. The results were in agreement with theoretical calculations. (author)

  5. Calculation of conversion coefficients of dose of a computational anthropomorphic simulator sit exposed to a plane source; Calculo de coeficientes de conversao de dose de um simulador antropomorfico computacional sentado exposto a uma fonte plana

    Energy Technology Data Exchange (ETDEWEB)

    Santos, William S.; Carvalho Junior, Alberico B. de; Pereira, Ariana J.S.; Santos, Marcos S.; Maia, Ana F., E-mail: williathan@yahoo.com.b, E-mail: ablohem@gmail.co, E-mail: ariana-jsp@hotmail.co, E-mail: m_souzasantos@hotmail.co, E-mail: afmaia@ufs.b [Universidade Federal de Sergipe (UFS), Aracaju, SE (Brazil)

    2011-10-26

    In this paper conversion coefficients (CCs) of equivalent dose and effective in terms of kerma in the air were calculated suggested by the ICRP 74. These dose coefficients were calculated considering a plane radiation source and monoenergetic for a spectrum of energy varying from 10 keV to 2 MeV. The CCs were obtained for four geometries of irradiation, anterior-posterior, posterior-anterior, lateral right side and lateral left side. It was used the radiation transport code Visual Monte Carlo (VMC), and a anthropomorphic simulator of sit female voxel. The observed differences in the found values for the CCs at the four irradiation sceneries are direct results of the body organs disposition, and the distance of these organs to the irradiation source. The obtained CCs will be used for estimative more precise of dose in situations that the exposed individual be sit, as the normally the CCs available in the literature were calculated by using simulators always lying or on their feet

  6. European project for developing general guidelines for harmonising internal dose assessment procedures (IDEAS)

    International Nuclear Information System (INIS)

    Andrasi, A.; Bailey, M.; Puncher, M.; Berkovski, V.; Eric Blanchardon, E.; Jourdain, J.-R.; Carlo-Maria Castellani, C.-M.; Doerfel, H.; Christian Hurtgen, Ch.; Le Guen, B.

    2003-01-01

    Several international intercomparison exercises on intake and internal dose assessments from monitoring data led to the conclusion that the results calculated by different participants varied significantly mainly because of the wide variety of methods and assumptions applied in the assessment procedure. Based on these experiences the need for harmonisation of the procedures has been formulated as an EU research project under the 5 th Framework Programme (2001-2005), with the aim of developing general guidelines for standardising assessments of intakes and internal doses. In the IDEAS project eight institutions from seven European countries are participating using inputs also from internal dosimetry professionals from across Europe to ensure broad consensus in the outcome of the project. The IDEAS project is explained

  7. Evaluation of internal dose of handlers of radioisotopes and radiopharmaceuticals for medical use

    International Nuclear Information System (INIS)

    Cesar, R.B.P.; Mesquita, C.H. de

    1987-01-01

    The internal dose of workers from IPEN/CNEN-SP (Brazil) is evaluated according to models described by the ICPR-30 (International Comission on Radiological Protection). The workers, monitored by a whole-body counter, are divided into six groups: research and development, routine production, quality control, packaging, radiological protection and maintenance. The results of 970 counting, done in three years, are presented. (M.C.A.) [pt

  8. Internal radiation doses of people in Finland after the Chernobyl accident

    International Nuclear Information System (INIS)

    Suomela, M.; Rahola, T.

    1997-01-01

    After the reactor accident in Chernobyl radionuclides carried by airstreams reached Finland on April 27, 1986. The radioactive cloud spread over central and southern Finland and to a lesser extent over northern Finland. In Helsinki the maximum radionuclide concentrations in air were measured in late evening of April 28. The radioactive cloud remained over Finland only a short time and within a few days the radionuclide concentrations in the air decreased to one-hundredth of the maximum values. Most radionuclides causing deposition were washed down by local showers, resulting in very uneven deposition of radionuclides on the ground. In a addition minor amounts of radioactivity were deposited on Mav 10-12. For internal and external dose estimations Finland was divided into five fallout regions (1-5) according to the increasing 137 Cs surface activity. At first, the short-lived radionuclides as well as 134 Cs and 137 Cs contributed to the external dose rate. Only the long-lived isotopes, 134 Cs and especially 137 Cs, later determined the external dose rates. The regions and corresponding dose rates and deposition categories on October 1, 1987, are shown.To estimate the total dose of the Finnish population from the radionuclides originating at Chernobyl the effective external and internal doses were calculated; the external doses were estimated using the data given. Groups of Finnish people representing the five fallout regions were whole-body counted annually during 1986-1990. The results of these measurements and those of the reference group were used to estimate the internal body burdens and radiation doses from 134 Cs and 137 Cs to the population

  9. Doses from external and internal radiation in Norway during the first year after the Chernobyl accident

    International Nuclear Information System (INIS)

    Strand, P.; Kjoelaas, G.; Reitan, J.B.; Strand, T.; Berthelsen, T.; Selnaes, T.D.

    1990-01-01

    In this article the estimation of monthly doses from external radiation from internal radiation due to ingestion of contaminated food is reported. The monthly doses is estimated for each municipality in Norway for the first 13 months after the Chernobyl accident (from May 1986 to June 1987). The estimation which has been elaborated from an extensive data material, shows that the dose rates from external radiation due to the Chernobyl fallout were for the country as a whole three times higher in the first month after the accident (May 1986) compared with the twelfth month (April 1987). The doses received from intake of radiocesium through food were small in the first three months, but reached almost the double of the doses from the external radiation the 9th month. The reduction in the dose from external radiation was primarily due to the physical half life of radiocesium and washout. The increase in the doses from radiocesium through intake of food was due to the time required for radiocesium to enter the food chain and the biokinetics of radiocesium in humans. There is no significant correlation between the ground activity levels and the activity levels observed in the food which is consumed in the same area. The average internal dose in the first year after the Chernobyl accident was estimated to 0.110 ± 0.006 mSv and the external dose to 0.070 ± 0.007 mSv as an average for the whole country. 13 refs., 3 figs., 4 tabs

  10. ARN Training on Advance Methods for Internal Dose Assessment: Application of Ideas Guidelines

    International Nuclear Information System (INIS)

    Rojo, A.M.; Gomez Parada, I.; Puerta Yepes, N.; Gossio, S.

    2010-01-01

    Dose assessment in case of internal exposure involves the estimation of committed effective dose based on the interpretation of bioassay measurement, and the assumptions of hypotheses on the characteristics of the radioactive material and the time pattern and the pathway of intake. The IDEAS Guidelines provide a method to harmonize dose evaluations using criteria and flow chart procedures to be followed step by step. The EURADOS Working Group 7 'Internal Dosimetry', in collaboration with IAEA and Czech Technical University (CTU) in Prague, promoted the 'EURADOS/IAEA Regional Training Course on Advanced Methods for Internal Dose Assessment: Application of IDEAS Guidelines' to broaden and encourage the use of IDEAS Guidelines, which took place in Prague (Czech Republic) from 2-6 February 2009. The ARN identified the relevance of this training and asked for a place for participating on this activity. After that, the first training course in Argentina took place from 24-28 August for training local internal dosimetry experts. This paper resumes the main characteristics of this activity. (authors) [es

  11. Overview of internal dose evaluation in the radiopharmaceutical production plant at IPEN

    International Nuclear Information System (INIS)

    Todo, Alberto S.; Gerulis, Eduardo; Cardoso, Joaquim C.S.; Rodrigues Junior, Orlando

    2015-01-01

    The internal dosimetry program at the Instituto de Pesquisas Energeticas e Nucleares, IPEN, is accomplished in two steps: the activity measurements are performed at the In Vivo Monitoring Laboratory and subsequently the data analysis and the dose evaluation are carried out by the Dose Calculation Group according to the ICRP models. The objective of this study is to take the whole body and thyroid monitoring results recorded from 2005 to 2015 to see whether the internal contamination control procedure for workers were suitable even with the increase in the radiopharmaceutical production. The study were based in a research called “Search of Variables” for the operations carried out in the restricted areas of radiopharmaceutical production plant, taking into account the dose distribution data for all the tasks recorded by the radioprotection service. This methodology aims to identify and determine the principal variables that impact on the worker's dose. The results were presented for the following variables: individual occupationally exposed, operation variable, area/cell, type of task of operation, which depend on the variable dose. In spite of growth rate in the production of radiopharmaceutical, this study has shown that the improvements in the plant have contributed to the dose reduction of the workers. (author)

  12. Measurement of conversion coefficients between air Kerma and personal dose equivalent and backscatter factors for diagnostic X-ray beams; Determinacao experimental dos coeficientes de conversao de Kerma no ar para o equivalente de dose pessoal, Hp(d), e fatores de retroespalhamento em feixes de raios-x diagnostico

    Energy Technology Data Exchange (ETDEWEB)

    Rosado, Paulo Henrique Goncalves

    2008-07-01

    Two sets of quantities are import in radiological protection: the protection and operational quantities. Both sets can be related to basic physical quantities such as kerma through conversion coefficients. For diagnostic x-ray beams the conversion coefficients and backscatter factors have not been determined yet, those parameters are need for calibrating dosimeters that will be used to determine the personal dose equivalent or the entrance skin dose. Conversion coefficients between air kerma and personal dose equivalent and backscatter factors were experimentally determined for the diagnostic x-ray qualities RQR and RQA recommended by the International Electrotechnical Commission (IEC). The air kerma in the phantom and the mean energy of the spectrum were measured for such purpose. Harshaw LiF-100H thermoluminescent dosemeters (TLD) were used for measurements after being calibrated against an 180 cm{sup 3} Radcal Corporation ionization chamber traceable to a reference laboratory. A 300 mm x 300 mm x 150 mm polymethylmethacrylate (PMMA) slab phantom was used for deep-dose measurements. Tl dosemeters were placed in the central axis of the x-ray beam at 5, 10, 15, 25 and 35 mm depth in the phantom upstream the beam direction Another required parameter for determining the conversion coefficients from was the mean energy of the x-ray spectrum. The spectroscopy of x-ray beams was done with a CdTe semiconductor detector that was calibrated with {sup 133} Ba, {sup 241} Am and {sup 57} Co radiation sources. Measurements of the x-ray spectra were carried out for all RQR and RQA IEC qualities. Corrections due to the detector intrinsic efficiency, total energy absorption, escape fraction of the characteristic x-rays, Compton effect and attenuation in the detector were done aiming an the accurate determination of the mean energy. Measured x-ray spectra were corrected with the stripping method by using these response functions. The typical combined standard uncertainties of

  13. The Assessment of I-131 Internal Doses of Nuclear Medicine Workers in Korea Using Thyroid uptake system

    International Nuclear Information System (INIS)

    Bahn, Young Kag; Oh, Gi Back; Lee, Chang Ho; Lee, Jong Doo; Yeom, Yu Sun; Hwang, Young Muk

    2012-01-01

    There are possibilities the radiation workers could intake the radiation when workers deal with radiation-materials. Therefore, internal radiation doses of radiation workers need to be assessed. Although an application of the nuclear medicine is continuously increased in Korea, there is not a proper tool and form to monitor the internal doses of nuclear medicine workers. However, it is possible to attain the internal doses of I-131 to evaluate using thyroid uptake and well count system. In this study, we measured and evaluated the I-131 internal doses of nuclear medicine workers in Korea using thyroid uptake and well count system and performed an air sampling

  14. Estimation of internal exposure dose from food after the Fukushima Daiichi Nuclear Power Station disaster

    International Nuclear Information System (INIS)

    Takizawa, Mari; Yoshizawa, Nobuaki; Kawai, Masaki; Miyatake, Hirokazu; Hirakawa, Sachiko; Murakami, Kana; Sato, Osamu; Takagi, Shunji; Suzuki, Gen

    2016-01-01

    In order to estimate the internal exposure dose from food due to the Fukushima Daiichi Nuclear Power Station accident, total diet study (TDS) has been carried out. TDS is a method for estimating how much of certain chemicals people intake in the normal diet. A wide range of food products are chosen as targets, and the increase or decrease of chemicals depending on processing or cooking is taken into account. This paper glanced at the transition of TDS survey results, and with a focus on the survey results of the market basket (MB) system, which is one of the TDS techniques, it examined a decrease in the committed effective dose per year of radioactive cesium. Although the values of internal exposure dose from food in Fukushima Prefecture and surrounding prefectures are even now in a relatively high tendency compared with those in the distant regions, the difference has been narrowing. According to the attenuation prediction of internal exposure dose in each region of Fukushima Prefecture, the values after 5 years from the accident will be lower than the measured value on the food in market that has been investigated during 1989 and 2005. In addition, the internal exposure dose that was the survey results based on MB system in September - October 2014 was 0.0007 to 0.0022 mSv/year. These values are very small at 1% or less of the upper limit dose of 1 mSv/year as the setting basis of current reference value in Japan. (A.O.)

  15. General guidelines for the assessment of internal dose from monitoring data: Progress of the IDEAS project

    International Nuclear Information System (INIS)

    Doerfel, H.; Andrasi, A.; Bailey, M.; Blanchardon, E.; Cruz-Suarez, R.; Berkovski, V.; Castellani, C. M.; Hurtgenv, C.; Leguen, B.; Malatova, I.; Marsh, J.; Stather, J.; Zeger, J.

    2007-01-01

    In recent major international intercomparison exercises on intake and internal dose assessments from monitoring data, the results calculated by different participants varied significantly. Based on this experience the need for harmonisation of the procedures has been formulated within an EU 5. Framework Programme research project. The aim of the project, IDEAS, is to develop general guidelines for standardising assessments of intakes and internal doses. The IDEAS project started in October 2001 and ended in June 2005. The project is closely related to some goals of the work of Committee 2 of the ICRP and since 2003 there has been close cooperation between the two groups. To ensure that the guidelines are applicable to a wide range of practical situations, the first step was to compile a database of well-documented cases of internal contamination. In parallel, an improved version of an existing software package was developed and distributed to the partners for further use. A large number of cases from the database was evaluated independently by the partners and the results reviewed. Based on these evaluations, guidelines were drafted and discussed with dosimetry professionals from around the world by means of a virtual workshop on the Internet early in 2004. The guidelines have been revised and refined on the basis of the experiences and discussions in this virtual workshop. The general philosophy of the Guidelines is presented here, focusing on the principles of harmonisation, optimisation and proportionality. Finally, the proposed Levels of Task to structure the approach of internal dose evaluation are reported. (authors)

  16. Calculation of Oil Film Thickness from Damping Coefficients for a Piston Ring in an Internal Combustion Engine

    DEFF Research Database (Denmark)

    Christiansen, Jens; Klit, Peder; Vølund, Anders

    2007-01-01

    engine. The basic idea is to use the fluid film damping coefficients to estimate the film thickness variation for a piston ring under cyclic varying load. Reynolds Equation is solved for a piston ring and the oil film thickness is determined. In this analysis hydrodynamic lubrication is assumed......In 1966 Jorgen W. Lund published an approach to find the dynamic coefficients of a journal bearing by a first order perturbation of the Reynold's equation. These coefficients made it possible to perform a rotor-bearing stability analysis for a statically loaded bearing. In the mid seventies Jorgen...

  17. INTDOS: a computer code for estimating internal radiation dose using recommendations of the International Commission on Radiological Protection

    International Nuclear Information System (INIS)

    Ryan, M.T.

    1981-09-01

    INTDOS is a user-oriented computer code designed to calculate estimates of internal radiation dose commitment resulting from the acute inhalation intake of various radionuclides. It is designed so that users unfamiliar with the details of such can obtain results by answering a few questions regarding the exposure case. The user must identify the radionuclide name, solubility class, particle size, time since exposure, and the measured lung burden. INTDOS calculates the fractions of the lung burden remaining at time, t, postexposure considering the solubility class and particle size information. From the fraction remaining in the lung at time, t, the quantity inhaled is estimated. Radioactive decay is accounted for in the estimate. Finally, effective committed dose equivalents to various organs and tissues of the body are calculated using inhalation committed dose factors presented by the International Commission on Radiological Protection (ICRP). This computer code was written for execution on a Digital Equipment Corporation PDP-10 computer and is written in Fortran IV. A flow chart and example calculations are discussed in detail to aid the user who is unfamiliar with computer operations

  18. Internal dose assessment data management system for a large population of Pu workers

    International Nuclear Information System (INIS)

    Bertelli, L.; Miller, G.; Little, T.; Guilmette, R.A.; Glasser, S.M.

    2007-01-01

    This paper describes the design and implementation of the Los Alamos National Laboratory (LANL) dose assessment (DA) data system. Dose calculations for the most important radionuclides at LANL, namely plutonium, americium, uranium and tritium, are performed through the Microsoft Access DA database. DA includes specially developed forms and macros that perform a variety of tasks, such as retrieving bioassay data, launching the FORTRAN internal dosimetry applications and displaying dose results in the form of text summaries and plots. The DA software involves the following major processes: (1) downloading of bioassay data from a remote data source, (2) editing local and remote databases, (3) setting up and carrying out internal dose calculations using the UF code or the ID code, (3) importing results of the dose calculations into local results databases, (4) producing a secondary database of 'official results' and (5) automatically creating and e-mailing reports. The software also provides summary status and reports of the pending DAs, which are useful for managing the cases in process. (authors)

  19. MO-DE-204-00: International Symposium: Patient Dose Reduction in Diagnostic Radiology

    International Nuclear Information System (INIS)

    2016-01-01

    The main topic of the session is to show how dose optimization is being implemented in various regions of the world, including Europe, Australia, North America and other regions. A multi-national study conducted under International Atomic Energy Agency (IAEA) across more than 50 less resourced countries gave insight into patient radiation doses and safety practices in CT, mammography, radiography and interventional procedures, both for children and adults. An important outcome was the capability development on dose assessment and management. An overview of recent European projects related to CT radiation dose and optimization both to adults and children will be presented. Existing data on DRLs together with a European methodology proposed on establishing and using DRLs for paediatric radiodiagnostic imaging and interventional radiology practices will be shown. Compared with much of Europe at least, many Australian imaging practices are relatively new to the task of diagnostic imaging dose optimisation. In 2008 the Australian Government prescribed a requirement to periodically compare patient radiation doses with diagnostic reference levels (DRLs), where DRLs have been established. Until recently, Australia had only established DRLs for computed tomography (CT). Regardless, both professional society and individual efforts to improved data collection and develop optimisation strategies across a range of modalities continues. Progress in this field, principally with respect to CT and interventional fluoroscopy will be presented. In the US, dose reduction and optimization efforts for computed tomography have been promoted and mandated by several organizations and accrediting entities. This presentation will cover the general motivation, implementation, and implications of such efforts. Learning Objectives: Understand importance of the dose optimization in Diagnostic Radiology. See how this goal is achieved in different regions of the World. Learn about the global trend

  20. MO-DE-204-00: International Symposium: Patient Dose Reduction in Diagnostic Radiology

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2016-06-15

    The main topic of the session is to show how dose optimization is being implemented in various regions of the world, including Europe, Australia, North America and other regions. A multi-national study conducted under International Atomic Energy Agency (IAEA) across more than 50 less resourced countries gave insight into patient radiation doses and safety practices in CT, mammography, radiography and interventional procedures, both for children and adults. An important outcome was the capability development on dose assessment and management. An overview of recent European projects related to CT radiation dose and optimization both to adults and children will be presented. Existing data on DRLs together with a European methodology proposed on establishing and using DRLs for paediatric radiodiagnostic imaging and interventional radiology practices will be shown. Compared with much of Europe at least, many Australian imaging practices are relatively new to the task of diagnostic imaging dose optimisation. In 2008 the Australian Government prescribed a requirement to periodically compare patient radiation doses with diagnostic reference levels (DRLs), where DRLs have been established. Until recently, Australia had only established DRLs for computed tomography (CT). Regardless, both professional society and individual efforts to improved data collection and develop optimisation strategies across a range of modalities continues. Progress in this field, principally with respect to CT and interventional fluoroscopy will be presented. In the US, dose reduction and optimization efforts for computed tomography have been promoted and mandated by several organizations and accrediting entities. This presentation will cover the general motivation, implementation, and implications of such efforts. Learning Objectives: Understand importance of the dose optimization in Diagnostic Radiology. See how this goal is achieved in different regions of the World. Learn about the global trend

  1. Fluence-to-dose conversion coefficients based on the posture modification of Adult Male (AM) and Adult Female (AF) reference phantoms of ICRP 110

    International Nuclear Information System (INIS)

    Galeano, D.C.; Santos, W.S.; Alves, M.C.; Souza, D.N.; Carvalho, A.B.

    2016-01-01

    The aim of this work was to modify the standing posture of the anthropomorphic reference phantoms of ICRP publication 110, AM (Adult Male) and AF (Adult Female), to the sitting posture. The change of posture was performed using the Visual Monte Carlo software (VMC) to rotate the thigh region of the phantoms and position it between the region of the leg and trunk. Scion Image software was used to reconstruct and smooth the knee and hip contours of the phantoms in a sitting posture. For 3D visualization of phantoms, the VolView software was used. In the change of postures, the organ and tissue masses were preserved. The MCNPX was used to calculate the equivalent and effective dose conversion coefficients (CCs) per fluence for photons for six irradiation geometries suggested by ICRP publication 110 (AP, PA, RLAT, LLAT, ROT and ISO) and energy range 0.010–10 MeV. The results were compared between the standing and sitting postures, for both sexes, in order to evaluate the differences of scattering and absorption of radiation for different postures. Significant differences in the CCs for equivalent dose were observed in the gonads, colon, prostate, urinary bladder and uterus, which are present in the pelvic region, and in organs distributed throughout the body, such as the lymphatic nodes, muscle, skeleton and skin, for the phantoms of both sexes. CCs for effective dose showed significant differences of up to 16% in the AP irradiation geometry, 27% in the PA irradiation geometry and 13% in the ROT irradiation geometry. These results demonstrate the importance of using phantoms in different postures in order to obtain more precise conversion coefficients for a given exposure scenario. - Highlights: • The reference phantoms AM and AF had modified its posture. • The AM and AF phantoms were irradiated in standing and sitting postures. • The irradiation geometry used were the AP, PA, LLAT, RLAT, ROT and ISO. • The CCs for standing and sitting postures were compared

  2. Signal intensity of normal breast tissue at MR mammography on midfield: Applying a random coefficient model evaluating the effect of doubling the contrast dose

    Energy Technology Data Exchange (ETDEWEB)

    Marklund, Mette [Parker Institute: Imaging Unit, Frederiksberg Hospital (Denmark)], E-mail: mm@frh.regionh.dk; Christensen, Robin [Parker Institute: Musculoskeletal Statistics Unit, Frederiksberg Hospital (Denmark)], E-mail: robin.christensen@frh.regionh.dk; Torp-Pedersen, Soren [Parker Institute: Imaging Unit, Frederiksberg Hospital (Denmark)], E-mail: stp@frh.regionh.dk; Thomsen, Carsten [Department of Radiology, Rigshospitalet, University of Copenhagen (Denmark)], E-mail: carsten.thomsen@rh.regionh.dk; Nolsoe, Christian P. [Department of Radiology, Koge Hospital (Denmark)], E-mail: cnolsoe@dadlnet.dk

    2009-01-15

    Purpose: To prospectively investigate the effect on signal intensity (SI) of healthy breast parenchyma on magnetic resonance mammography (MRM) when doubling the contrast dose from 0.1 to 0.2 mmol/kg bodyweight. Materials and methods: Informed consent and institutional review board approval were obtained. Twenty-five healthy female volunteers (median age: 24 years (range: 21-37 years) and median bodyweight: 65 kg (51-80 kg)) completed two dynamic MRM examinations on a 0.6 T open scanner. The inter-examination time was 24 h (23.5-25 h). The following sequences were applied: axial T2W TSE and an axial dynamic T1W FFED, with a total of seven frames. At day 1, an i.v. gadolinium (Gd) bolus injection of 0.1 mmol/kg bodyweight (Omniscan) (low) was administered. On day 2, the contrast dose was increased to 0.2 mmol/kg (high). Injection rate was 2 mL/s (day 1) and 4 mL/s (day 2). Any use of estrogen containing oral contraceptives (ECOC) was recorded. Post-processing with automated subtraction, manually traced ROI (region of interest) and recording of the SI was performed. A random coefficient model was applied. Results: We found an SI increase of 24.2% and 40% following the low and high dose, respectively (P < 0.0001); corresponding to a 65% (95% CI: 37-99%) SI increase, indicating a moderate saturation. Although not statistically significant (P = 0.06), the results indicated a tendency, towards lower maximal SI in the breast parenchyma of ECOC users compared to non-ECOC users. Conclusion: We conclude that the contrast dose can be increased from 0.1 to 0.2 mmol/kg bodyweight, if a better contrast/noise relation is desired but increasing the contrast dose above 0.2 mmol/kg bodyweight is not likely to improve the enhancement substantially due to the moderate saturation observed. Further research is needed to determine the impact of ECOC on the relative enhancement ratio, and further studies are needed to determine if a possible use of ECOC should be considered a compromising

  3. Signal intensity of normal breast tissue at MR mammography on midfield: Applying a random coefficient model evaluating the effect of doubling the contrast dose

    International Nuclear Information System (INIS)

    Marklund, Mette; Christensen, Robin; Torp-Pedersen, Soren; Thomsen, Carsten; Nolsoe, Christian P.

    2009-01-01

    Purpose: To prospectively investigate the effect on signal intensity (SI) of healthy breast parenchyma on magnetic resonance mammography (MRM) when doubling the contrast dose from 0.1 to 0.2 mmol/kg bodyweight. Materials and methods: Informed consent and institutional review board approval were obtained. Twenty-five healthy female volunteers (median age: 24 years (range: 21-37 years) and median bodyweight: 65 kg (51-80 kg)) completed two dynamic MRM examinations on a 0.6 T open scanner. The inter-examination time was 24 h (23.5-25 h). The following sequences were applied: axial T2W TSE and an axial dynamic T1W FFED, with a total of seven frames. At day 1, an i.v. gadolinium (Gd) bolus injection of 0.1 mmol/kg bodyweight (Omniscan) (low) was administered. On day 2, the contrast dose was increased to 0.2 mmol/kg (high). Injection rate was 2 mL/s (day 1) and 4 mL/s (day 2). Any use of estrogen containing oral contraceptives (ECOC) was recorded. Post-processing with automated subtraction, manually traced ROI (region of interest) and recording of the SI was performed. A random coefficient model was applied. Results: We found an SI increase of 24.2% and 40% following the low and high dose, respectively (P < 0.0001); corresponding to a 65% (95% CI: 37-99%) SI increase, indicating a moderate saturation. Although not statistically significant (P = 0.06), the results indicated a tendency, towards lower maximal SI in the breast parenchyma of ECOC users compared to non-ECOC users. Conclusion: We conclude that the contrast dose can be increased from 0.1 to 0.2 mmol/kg bodyweight, if a better contrast/noise relation is desired but increasing the contrast dose above 0.2 mmol/kg bodyweight is not likely to improve the enhancement substantially due to the moderate saturation observed. Further research is needed to determine the impact of ECOC on the relative enhancement ratio, and further studies are needed to determine if a possible use of ECOC should be considered a compromising

  4. Internal dose assessment due to large area contamination: Main lessons drawn from the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Andrasi, A [KFKI Atomic Energy Research Inst., Budapest (Hungary)

    1997-03-01

    The reactor accident at Chernobyl in 1986 beside its serious and tragic consequences provided also an excellent opportunity to check, test and validate all kind of environmental models and calculation tools which were available in the emergency preparedness systems of different countries. Assessment of internal and external doses due to the accident has been carried out for the population all over Europe using different methods. Dose predictions based on environmental model calculation considering various pathways have been compared with those obtained by more direct monitoring methods. One study from Hungary and one from the TAEA is presented shortly. (orig./DG)

  5. Internal dose assessment due to large area contamination: Main lessons drawn from the Chernobyl accident

    International Nuclear Information System (INIS)

    Andrasi, A.

    1997-01-01

    The reactor accident at Chernobyl in 1986 beside its serious and tragic consequences provided also an excellent opportunity to check, test and validate all kind of environmental models and calculation tools which were available in the emergency preparedness systems of different countries. Assessment of internal and external doses due to the accident has been carried out for the population all over Europe using different methods. Dose predictions based on environmental model calculation considering various pathways have been compared with those obtained by more direct monitoring methods. One study from Hungary and one from the TAEA is presented shortly. (orig./DG)

  6. Pharmacokinetic/Pharmacodynamic Modelling of Receptor Internalization with CRTH2 Antagonists to Optimize Dose Selection.

    Science.gov (United States)

    Krause, Andreas; Zisowsky, Jochen; Strasser, Daniel S; Gehin, Martine; Sidharta, Patricia N; Groenen, Peter M A; Dingemanse, Jasper

    2016-07-01

    The chemoattractant receptor-homologous molecule expressed on T helper-2 cells (CRTH2) is a G-protein-coupled receptor for prostaglandin D2 (PGD2), a key mediator in inflammatory disorders. Two selective and potent CRTH2 antagonists currently in clinical development, ACT-453859 and setipiprant, were compared with respect to their (predicted) clinical efficacy. Population pharmacokinetic (PK) and pharmacodynamic (PD) models were developed to characterize how plasma concentrations (PK) of ACT-453859, its active metabolite ACT-463036 and setipiprant related to their effect on blocking PGD2-induced internalization of CRTH2 on eosinophils (PD). Simulations were used to identify doses and dosing regimens leading to 90 % of maximum blockade of CRTH2 internalization at trough. A combined concentration of ACT-453859 and its metabolite ACT-463036, with weights proportional to potency (based on an eosinophil shape change assay), enabled good characterization of the PD effect. The modelling and simulation results facilitated decision making by suggesting an ACT-453859 dose of 400 mg once daily (or 100 mg twice daily) for clinically relevant CRTH2 antagonism. Pharmacometric quantification demonstrated that CRTH2 internalization is a useful new biomarker to study CRTH2 antagonism. Ninety percent of maximum blockade of CRTH2 internalization at trough is suggested as a quantitative PD target in clinical studies.

  7. Estimation of internal exposure dose caused by 3H releasted at QNPP base

    International Nuclear Information System (INIS)

    Liang Meiyan; Ma Yongfu; Ni Shiying; Zhang Xinyu

    2010-01-01

    QNPP III is the first heavy water reactors nuclear power plant in China, with its 1, 2 units generating electricity in November 2002 and June 2003, respectively. This paper, based on the monitoring data of tritium concentration in environmental samples at Xiajiawan, Yangliucun, Qinlian, Qinshanzheng and Wuyuanzheng (sampling points) in the external environment around QNPP Base, in combination with the study on living and eating habits of residents around QNPP Base, presents estimated annual tritium intake of air, drinking water and food for residents (not including the organic combination tritium). In accordance with the new dose coefficient at different ages recommended by ICRP 72 Publication, it is calculated that the tritium annual intake by various approaches for infants, children and adults (at the Xiajiawan resident point) are 5.75, 9.59, 15.7 kBq/a, respectively; the annual committed effective dose are 0.33, 0.18, 0.23 μSv/a respectively. The infant group would receive the largest committed effective dose from tritium, 0.33/μSv/a, but this is only less than 1% of the effective target dose (0.05 mSv). In all, the tritium impact on surrounding areas of QNPP Phase III is very small under the normal and safe operation of HWR. (authors)

  8. The role of intercomparisons and intercalibrations in the improvement of internal dose assessment

    International Nuclear Information System (INIS)

    Griffith, R.V.

    2000-01-01

    In vivo monitoring and dose assessment is a highly technical field. Moreover, it is carried out by a relatively small number of specialists. A number of technical steps can be taken to improve internal dosimetry programmes. However, one of the most valuable activities for overall improvement of measurement programmes is active participation in national and international intercomparisons and intercalibrations. These bring a number of benefits to the internal dosimetry programme, including validation of measurement practices, harmonisation of techniques, information exchange, and training. The number of intercalibration and intercomparison activities conducted on the national and international level has grown in recent years. These activities may involve actual measurement programmes or calculation exercises to compare approaches used for assessment of internal dose from measurement results. When conducted effectively such programmes are a highly cost effective use of limited resources. They also contribute to the credibility of the overall dosimetry process. Intercomparisons should be an important component of the in vivo measurement programme. Cooperation between the organisers of various intercomparison activities is essential to avoid unnecessary duplication and ensure the most effective use of the participants' time and energy. Future activities should address the use of simplified phantoms and source arrays to expedite shipping, reduce cost, and contribute to more timely conduct of intercomparisons. It is also important that managers and regulatory authorities be prepared to support intercomparison and intercalibration programmes. (author)

  9. Scattering factor evaluation for internal dose assessment due to 60Co

    International Nuclear Information System (INIS)

    Gautam, Y.P.; Kumar, A.; Sharma, S.; Sharma, A.K.; Dube, B.; Hegde, A.G.

    2008-01-01

    Guidelines for the assessment of internal doses from monitoring suggest default measurement of uncertainties (i.e. lognormal scattering factor, SF) to be used for different types of monitoring data. In this paper, SF values have been evaluated for internal contamination due to 60 Co in two cases using whole body counting data. SF values of 1.04 and 1.03 were obtained for case I and II respectively while SF value of 1.03 was obtained using bioassay data for case I. SF evaluated is in good agreement with the default values given by IDEAS guidelines. (author)

  10. Emergency preparedness in Finland: improvement of the measurement equipment used in the assessment of internal doses

    Energy Technology Data Exchange (ETDEWEB)

    Muikku, M.; Rahola, T. [STUK - Radiation and nuclear safety authority, Helsinki (Finland)

    2006-07-01

    The need for assessing internal radiation doses in emergency situations is evident. Internal exposure can be assessed using direct measurement results or by using information on activity concentrations in inhaled air and in foodstuffs combined with inhalation and consumption data. As a part of the continuous improving of emergency preparedness in Finland, S.T.U.K. - Radiation and Nuclear Safety Authority has obtained 35 monitors for thyroid measurements in field conditions and initiated a project to revise the radiation measurement equipment in local food and environmental laboratories. (authors)

  11. Methods for estimation of internal dose of the public from dietary

    International Nuclear Information System (INIS)

    Zhu Hongda

    1987-01-01

    Following the issue of its Publication 26, ICRP has successively published its Publication 30 to meet the great changes and improvements made in the Basic Recommendations since July of 1979. In Part 1 of Publcation 30, ICRP recommended a new method for internal dose estimation and pressented some important data. In this report, comparison is made among methods for estimation of internal dose for the public from dietary. They include: (1) the new method suggested by ICRP; (2) the simple and convenient method using transfer factors under equilibrium conditions; (3) the methods based on the similarities of several radionuclides to their chemical analogs. It is concluded that the first method is better than the others and should be used from now on

  12. Characterization of aerosols in uranium handling facilities and its impact on the assessment of internal dose

    International Nuclear Information System (INIS)

    Roy, Ankush; Rao, D.D.; Sawant, Pramilla D.; Khan, Arshad; Srinivasan, P.; Chandrashekara, A.

    2016-01-01

    In nuclear facilities, compounds of uranium such as Magnesium DiUranate (MDU) U 3 O 8 , UO 2 etc. are handled in different stages of operation. There may be a possibility of intake of these compounds by radiation workers during the course of their work. The internal doses received by the workers depend not only on the quantity but also the physiochemical characteristics of the radioactive contaminant. The depositions in different regions of lung of these inhaled aerosols depend on their particle size; whereas the clearance is dependent upon the chemical nature. In this study, aerosol characterization is carried out in four different Uranium Handling Facilities (UF) for realistic assessment of internal dose to the radiation worker

  13. An international pooled analysis for obtaining a benchmark dose for environmental lead exposure in children

    DEFF Research Database (Denmark)

    Budtz-Jørgensen, Esben; Bellinger, David; Lanphear, Bruce

    2013-01-01

    Lead is a recognized neurotoxicant, but estimating effects at the lowest measurable levels is difficult. An international pooled analysis of data from seven cohort studies reported an inverse and supra-linear relationship between blood lead concentrations and IQ scores in children. The lack...... of a clear threshold presents a challenge to the identification of an acceptable level of exposure. The benchmark dose (BMD) is defined as the dose that leads to a specific known loss. As an alternative to elusive thresholds, the BMD is being used increasingly by regulatory authorities. Using the pooled data...... yielding lower confidence limits (BMDLs) of about 0.1-1.0 μ g/dL for the dose leading to a loss of one IQ point. We conclude that current allowable blood lead concentrations need to be lowered and further prevention efforts are needed to protect children from lead toxicity....

  14. IDACstar: A MCNP Application to Perform Realistic Dose Estimations from Internal or External Contamination of Radiopharmaceuticals.

    Science.gov (United States)

    Ören, Ünal; Hiller, Mauritius; Andersson, M

    2017-04-28

    A Monte Carlo-based stand-alone program, IDACstar (Internal Dose Assessment by Computer), was developed, dedicated to perform radiation dose calculations using complex voxel simulations. To test the program, two irradiation situations were simulated, one hypothetical contamination case with 600 MBq of 99mTc and one extravasation case involving 370 MBq of 18F-FDG. The effective dose was estimated to be 0.042 mSv for the contamination case and 4.5 mSv for the extravasation case. IDACstar has demonstrated that dosimetry results from contamination or extravasation cases can be acquired with great ease. An effective tool for radiation protection applications is provided with IDACstar allowing physicists at nuclear medicine departments to easily quantify the radiation risk of stochastic effects when a radiation accident has occurred. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  15. A consideration on internal dose evaluation and intervention based on a surface contamination concept

    International Nuclear Information System (INIS)

    Yasuda, H.

    1997-01-01

    Long-term radiation doses received by the inhabitants after the Chernobyl accident have been evaluated according to the surface contamination levels on the ground surface. The health effects have also been discussed by comparison between the surface-contaminated area and the uncontaminated control area. Selected protective measures were carried out in accordance with the contamination level of surface soil. These have been based on the 'surface contamination concept' which assumes that the radiation risk to inhabitants is proportional to the level of ground-surface contamination. The observations collected in regions around Chernobyl, however, show that the internal radiation doses to the inhabitants poorly correlate with the surface contamination level. This fact poses a question on the suitability of dose evaluations and interventions based on this concept

  16. A development of computer code for evaluating internal radiation dose through ingestion and inhalation pathways

    International Nuclear Information System (INIS)

    Lee, Jeong Ho; Lee, Chang Woo; Choi, Yong Ho; Chun, Ki Jung; Kim, Kook Chan; Kim, Sang Bok; Kim, Jin Kyu

    1991-07-01

    The computer codes were developed to evaluate internal radiation dose when radioactive isotopes released from nuclear facilities are taken through ingestion and inhalation pathways. Food chain models and relevant data base representing the agricultural and social environment of Korea are set up. An equilibrium model-KFOOD, which can deal with routine releases from a nuclear facility and a dynamic model-ECOREA, which is suitable for the description of acute radioactivity release following nuclear accident. (Author)

  17. Internal dose assessment of 238U contaminated soils based on in-vitro gastrointestinal protocol

    Science.gov (United States)

    Perama, Yasmin Mohd Idris; Rashid, Nur Shahidah Abdul; Majid, Amran Ab.; Siong, Khoo Kok

    2017-01-01

    Human exposure to natural radioactive uranium has been a great interest as more industrial rapidly growing contributes to radiation risks. The aim of this case study was to determine the internal dose in humans incorporated with ingestion of 238U contaminated soils. A gastrointestinal analogue test was employed to simulate the human digestive tract. In-vitro approach via German DIN 19738 model was developed in order to estimate the internal exposure of 238U due to ingestion of different types of soils. Synthetic gastrointestinal fluids assay via in-vitro method were produced to determine the concentration of 238U in various soils using ICP-MS. Based on the results, concentration of 238U in BRIS, laterite, peat and alluvium soils were in ranged between (0.0061 ± 0.0057 - 0.0488 ± 0.0148) ppm and (0.0005 ± 0.0004 - 0.0046 ± 0.0007) ppm in gastric and gastrointestinal phase respectively. Types of soil compositions and pH medium were some of the factors that influence mobilization and solubility of 238U contaminanted soil into the digestive juices that resembles human gastrointestinal tract. For the purpose of internal dose assessment, the committed efective dose from 238U intake in soils ranged between 1.237 × 10-11 - 9.8993 × 10-11 Sv y-1 for gastric phase and 1.0184 × 10-12 - 9.3294 × 10-12 Sv y-1 for gastric-intestinal phase. The internal dose measurements from this study were much lower from the recommended values. Hence, ingestion of 238U contaminated soils would not be expected to pose major health risk to humans.

  18. Issues in weighting bioassay data for use in regressions for internal dose assessments

    International Nuclear Information System (INIS)

    Strom, D.J.

    1992-11-01

    For use of bioassay data in internal dose assessment, research should be done to clarify the goal desired, the choice of method to achieve the goal, the selection of adjustable parameters, and on the ensemble of information that is available. Understanding of these issues should determine choices of weighting factors for bioassay data used in regression models. This paper provides an assessment of the relative importance of the various factors

  19. Establishing bounding internal dose estimates for thorium activities at Rocky Flats.

    Science.gov (United States)

    Ulsh, Brant A; Rich, Bryce L; Chew, Melton H; Morris, Robert L; Sharfi, Mutty; Rolfes, Mark R

    2008-07-01

    As part of an evaluation of a Special Exposure Cohort petition filed on behalf of workers at the Rocky Flats Plant, the National Institute for Occupational Safety and Health (NIOSH) was required to demonstrate that bounding values could be established for radiation doses due to the potential intake of all radionuclides present at the facility. The main radioactive elements of interest at Rocky Flats were plutonium and uranium, but much smaller quantities of several other elements, including thorium, were occasionally handled at the site. Bounding potential doses from thorium has proven challenging at other sites due to the early historical difficulty in detecting this element through urinalysis methods and the relatively high internal dose delivered per unit intake. This paper reports the results of NIOSH's investigation of the uses of thorium at Rocky Flats and provides bounding dose reconstructions for these operations. During this investigation, NIOSH reviewed unclassified reports, unclassified extracts of classified materials, material balance and inventory ledgers, monthly progress reports from various groups, and health physics field logbooks, and conducted interviews with former Rocky Flats workers. Thorium operations included: (1) an experimental metal forming project with 240 kg of thorium in 1960; (2) the use of pre-formed parts in weapons mockups; (3) the removal of Th from U; (4) numerous analytical procedures involving trace quantities of thorium; and (5) the possible experimental use of thorium as a mold coating compound. The thorium handling operations at Rocky Flats were limited in scope, well-monitored and documented, and potential doses can be bounded.

  20. The spatiotemporal dynamic analysis of the implied market information and characteristics of the correlation coefficient matrix of the international crude oil price returns

    International Nuclear Information System (INIS)

    Tian, Lixin; Ding, Zhenqi; Zhen, Zaili; Wang, Minggang

    2016-01-01

    The international crude oil market plays a crucial role in economies, and the studies of the correlation, risk and synchronization of the international crude oil market have important implications for the security and stability of the country, avoidance of business risk and people's daily lives. We investigate the information and characteristics of the international crude oil market (1999-2015) based on the random matrix theory (RMT). Firstly, we identify richer information in the largest eigenvalues deviating from RMT predictions for the international crude oil market; the international crude oil market can be roughly divided into ten different periods by the methods of eigenvectors and characteristic combination, and the implied market information of the correlation coefficient matrix is advanced. Secondly, we study the characteristics of the international crude oil market by the methods of system risk entropy, dynamic synchronous ratio, dynamic non-synchronous ratio and dynamic clustering algorithm. The results show that the international crude oil market is full of risk. The synchronization of the international crude oil market is very strong, and WTI and Brent occupy a very important position in the international crude oil market. (orig.)

  1. The spatiotemporal dynamic analysis of the implied market information and characteristics of the correlation coefficient matrix of the international crude oil price returns

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Lixin [Jiangsu University, Energy Development and Environmental Protection Strategy Research Center, Zhenjiang, Jiangsu (China); Nanjing Normal University, School of Mathematical Sciences, Nanjing, Jiangsu (China); Ding, Zhenqi; Zhen, Zaili [Jiangsu University, Energy Development and Environmental Protection Strategy Research Center, Zhenjiang, Jiangsu (China); Wang, Minggang [Nanjing Normal University, School of Mathematical Sciences, Nanjing, Jiangsu (China)

    2016-08-15

    The international crude oil market plays a crucial role in economies, and the studies of the correlation, risk and synchronization of the international crude oil market have important implications for the security and stability of the country, avoidance of business risk and people's daily lives. We investigate the information and characteristics of the international crude oil market (1999-2015) based on the random matrix theory (RMT). Firstly, we identify richer information in the largest eigenvalues deviating from RMT predictions for the international crude oil market; the international crude oil market can be roughly divided into ten different periods by the methods of eigenvectors and characteristic combination, and the implied market information of the correlation coefficient matrix is advanced. Secondly, we study the characteristics of the international crude oil market by the methods of system risk entropy, dynamic synchronous ratio, dynamic non-synchronous ratio and dynamic clustering algorithm. The results show that the international crude oil market is full of risk. The synchronization of the international crude oil market is very strong, and WTI and Brent occupy a very important position in the international crude oil market. (orig.)

  2. A study of the effects of internal organ motion on dose escalation in conformal prostate treatments

    International Nuclear Information System (INIS)

    Happersett, Laura; Mageras, Gig S.; Zelefsky, Michael J.; Burman, Chandra M.; Leibel, Steven A.; Chui Chen; Fuks, Zvi; Bull, Sarah; Ling, C. Clifton; Kutcher, Gerald J.

    2003-01-01

    Background and purpose: To assess the effect of internal organ motion on the dose distributions and biological indices for the target and non-target organs for three different conformal prostate treatment techniques. Materials and methods: We examined three types of treatment plans in 20 patients: (1) a six field plan, with a prescribed dose of 75.6 Gy; (2) the same six field plan to 72 Gy followed by a boost to 81 Gy; and (3) a five field plan with intensity modulated beams delivering 81 Gy. Treatment plans were designed using an initial CT data set (planning) and applied to three subsequent CT scans (treatment). The treatment CT contours were used to represent patient specific organ displacement; in addition, the dose distribution was convolved with a Gaussian distribution to model random setup error. Dose-volume histograms were calculated using an organ deformation model in which the movement between scans of individual points interior to the organs was tracked and the dose accumulated. The tumor control probability (TCP) for the prostate and proximal half of seminal vesicles (clinical target volume, CTV), normal tissue complication probability (NTCP) for the rectum and the percent volume of bladder wall receiving at least 75 Gy were calculated. Results: The patient averaged increase in the planned TCP between plan types 2 and 1 and types 3 and 1 was 9.8% (range 4.9-12.5%) for both, whereas the corresponding increases in treatment TCP were 9.0% (1.3-16%) and 8.1% (-1.3-13.8%). In all patients, plans 2 and 3 (81 Gy) exhibited equal or higher treatment TCP than plan 1 (75.6 Gy). The maximum treatment NTCP for rectum never exceeded the planning constraint and percent volume of bladder wall receiving at least 75 Gy was similar in the planning and treatment scans for all three plans. Conclusion: For plans that deliver a uniform prescribed dose to the planning target volume (PTV) (plan 1), current margins are adequate. In plans that further escalate the dose to part

  3. Doses and risk estimates to the human conceptus due to internal prenatal exposure to radioactive caesium

    International Nuclear Information System (INIS)

    Kalef-Ezra, J.A.

    1997-01-01

    The 1986 nuclear reactor accident at Chernobyl resulted in widespread internal contamination by radioactive caesium. The aim of the present study was to estimate the doses to embryos/fetus in Greece attributed to maternal 134 Cs and 137 Cs intake and the consequent health risks to their offspring. In pregnant women the concentration of total-body caesium (TBCs) was lower than in age-matched non-pregnant women measured during the same month. A detailed study of intake and retention in the members of one family carried out during the three years that followed the accident indicated that the biological half-time of caesium in the women decreased by a factor of two shortly after conception. Then at partus, there was an increase in the biological half-time, reaching a value similar to that before conception. The total-body potassium concentration was constant over the entire period. Doses to the embryo/fetus due to maternal intake was estimated to be about 150 μGy maximally in those conceived between November 1986 and March 1987. When conception took place later, the prenatal dose followed an exponential reduction with a half-time of about 170 d. These prenatal doses do not exceed the doses from either the natural internal potassium, or from the usual external background sources. The risks attributed to maternal 134 Cs and 137 Cs intake were considerably lower than levels that would justify consideration of termination of a pregnancy. In the absence of these data however, 2500 otherwise wanted pregnancies in Greece were terminated following the Chernobyl accident. (author)

  4. General guidelines for the Assessment of Internal Dose from Monitoring Data (Project IDEAS)

    International Nuclear Information System (INIS)

    Doerfel, H.; Andrasi, A.; Bailey, M.; Blanchardon, E.; Berkovski, V.; Castellani, C. M.; Hurtgen, C.; Jourdain, J. R.; LeGuen, B.; Puncher, M.

    2004-01-01

    In recent major international intercomparison exercises on intake and internal dose assessments from monitoring data the results calculated by different participants varied significantly. This was mainly due to the broad variety of methods and assumptions applied in the assessment procedure. Based on these experiences the need for harmonisation of the procedures has been formulated within an EU research project under the 5th Framework Programme. The aim of the project, IDEAS, is to develop general guidelines for standardising assessments of intakes and internal doses. The IDEAS project started in October 2001 and will end in March 2005. Eight institutions from seven European countries are participating. Inputs from internal dosimetry professionals from across Europe are also being used to ensure a broad consensus in the outcome of the project. The IDEAS project is closely related to some goals of the work of Committee 2 of the ICRP and since 2003 there has been close cooperation between the two groups. To ensure that the guidelines are applicable to a wide range of practical situations, the first step has been to compile a database of well-documented cases of internal contamination. In parallel, an improved version of an existing software package has been developed and distributed to the partners for further use. A large number of cases from the database have been evaluated independently by partners in the project using the same software and the results have been reviewed. Based on these evaluations guidelines are being drafted and will be discussed with dosimetry professionals from around the world by means of a virtual workshop on the Internet early in 2004. The guidelines will be revised and refined on the basis of the experiences and discussions of this virtual workshop and the outcome of an intercomparison exercise organised as part of the project. This will be open to all internal dosimetry professionals. (Author) 10 refs

  5. Intercomparison exercise on internal dose assessment. Final report of a joint IAEA-IDEAS project

    International Nuclear Information System (INIS)

    2007-09-01

    There have been several intercomparison exercises organized already at national and international levels for the assessment of occupational exposure due to intakes of radionuclides. These intercomparison exercises revealed significant differences in approaches, methods and assumptions, and consequently in the results. Because of the relevance of the issue for internal dosimetrists, the IAEA organized a new intercomparison exercise in cooperation with the IDEAS project General Guidelines for the Evaluation of Incorporation Monitoring Data, launched under the 5th EU Framework Programme (EU Contract No. FIKR-CT2001-00160). This new intercomparison exercise focused especially on the effect of the guidelines for harmonization of internal dosimetry. It also considered the following aspects: - to provide possibilities for the participating laboratories to check the quality of their internal dose assessment methods in applying the recent ICRP recommendations (e.g. for the new respiratory tract model); - to compare different approaches in interpretation of internal contamination monitoring data; - to quantify the differences in internal dose assessments based on the new guidelines or on other procedures, respectively; - to provide some figures for the influence of the input parameters on the monitoring results; and - to provide a broad forum for information exchange. Several cases have been selected for this exercise with the aim of covering a wide range of practices in the nuclear fuel cycle and in medical applications. The cases were: 1. Acute intake of HTO; 2. Acute inhalation of fission products 137 Cs and 90 Sr; 3. Intake of 60 Co; 4. Repeated intakes of 131 I; 5. Intake of enriched uranium; 6. Single intake of plutonium radionuclides and 241 Am. An Internet based approach had been used for the presentation of the cases, collection of responses and potential discussion of the results. Solutions to these cases were reported by 80 participants worldwide. This report

  6. Acute and chronic intakes of fallout radionuclides by Marshallese from nuclear weapons testing at Bikini and Enewetak and related internal radiation doses.

    Science.gov (United States)

    Simon, Steven L; Bouville, André; Melo, Dunstana; Beck, Harold L; Weinstock, Robert M

    2010-08-01

    Annual internal radiation doses resulting from both acute and chronic intakes of all important dose-contributing radionuclides occurring in fallout from nuclear weapons testing at Bikini and Enewetak from 1946 through 1958 have been estimated for the residents living on all atolls and separate reef islands of the Marshall Islands. Internal radiation absorbed doses to the tissues most at risk to cancer induction (red bone marrow, thyroid, stomach, and colon) have been estimated for representative persons of all population communities for all birth years from 1929 through 1968, and for all years of exposure from 1948 through 1970. The acute intake estimates rely on a model using, as its basis, historical urine bioassay data, for members of the Rongelap Island and Ailinginae communities as well as for Rongerik residents. The model also utilizes fallout times of arrival and radionuclide deposition densities estimated for all tests and all atolls. Acute intakes of 63 radionuclides were estimated for the populations of the 20 inhabited atolls and for the communities that were relocated during the testing years for reasons of safety and decontamination. The model used for chronic intake estimates is based on reported whole-body, urine, and blood counting data for residents of Utrik and Rongelap. Dose conversion coefficients relating intake to organ absorbed dose were developed using internationally accepted models but specifically tailored for intakes of particulate fallout by consideration of literature-based evidence to choose the most appropriate alimentary tract absorption fraction (f1) values. Dose estimates were much higher for the thyroid gland than for red marrow, stomach wall, or colon. The highest thyroid doses to adults were about 7,600 mGy for the people exposed on Rongelap; thyroid doses to adults were much lower, by a factor of 100 or more, for the people exposed on the populated atolls of Kwajalein and Majuro. The estimates of radionuclide intake and

  7. Reliability of the ICRP's dose coefficients for members of the public: IV. Basis of the human alimentary tract model and uncertainties in model predictions

    International Nuclear Information System (INIS)

    Leggett, R.; Harrison, J.; Phipps, A.

    2007-01-01

    The biokinetic and dosimetric model of the gastrointestinal (GI) tract applied in current documents of the International Commission on Radiological Protection (ICRP) was developed in the mid-1960's. The model was based on features of a reference adult male and was first used by the ICRP in Publication 30, Limits for Intakes of Radionuclides by Workers (Part 1, 1979). In the late 1990's an ICRP task group was appointed to develop a biokinetic and dosimetric model of the alimentary tract that reflects updated information and addresses current needs in radiation protection. The new age-specific and gender-specific model, called the Human Alimentary Tract Model (HATM), has been completed and will replace the GI model of Publication 30 in upcoming ICRP documents. This paper discusses the basis for the structure and parameter values of the HATM, summarises the uncertainties associated with selected features and types of predictions of the HATM and examines the sensitivity of dose estimates to these uncertainties for selected radionuclides. Emphasis is on generic biokinetic features of the HATM, particularly transit times through the lumen of the alimentary tract, but key dosimetric features of the model are outlined, and the sensitivity of tissue dose estimates to uncertainties in dosimetric as well as biokinetic features of the HATM are examined for selected radionuclides. (authors)

  8. Development and use of a fifteen year-old equivalent mathematical phantom for internal dose calculations

    International Nuclear Information System (INIS)

    Jones, R.M.; Poston, J.W.; Hwang, J.L.; Jones, T.D.; Warner, G.G.

    1976-06-01

    The existence of a phantom based on anatomical data for the average fifteen-year-old provides for a proficient means of obtaining estimates of absorbed dose for children of that age. Dimensions representative of an average fifteen-year-old human, obtained from various biological and medical research, were transformed into a mathematical construct of idealized shapes of the exterior, skeletal system, and internal organs of a human. The idealization for an average adult presently in use by the International Commission on Radiological Protection was used as a basis for design. The mathematical equations describing the phantom were developed to be readily adaptable to present-day methods of dose estimation. Typical exposure situations in nuclear medicine have previously been modeled for existing phantoms. With no further development of the exposure model necessary, adaptation to the fifteen-year-old phantom demonstrated the utility of the design. Estimates of absorbed dose were obtained for the administration of two radiopharmaceuticals, /sup 99m/Tc-sulfur colloid and /sup 99m/Tc-DMSA

  9. Internal Dose from Food and Drink Ingestion in the Early Phase after the Accident

    Science.gov (United States)

    Kawai, Masaki; Yoshizawa, Nobuaki; Hirakawa, Sachiko; Murakami, Kana; Takizawa, Mari; Sato, Osamu; Takagi, Shunji; Miyatake, Hirokazu; Takahashi, Tomoyuki; Suzuki, Gen

    2017-09-01

    Activity concentrations in food and drink, represented by water and vegetables, have been monitored continuously since the Fukushima Daiichi Nuclear Power Plant accident, with a focus on radioactive cesium. On the other hand, iodine-131 was not measured systematically in the early phase after the accident. The activity concentrations of iodine-131 in food and drink are important to estimate internal exposure due to ingestion pathway. When the internal dose from ingestion in the evacuation areas is estimated, water is considered as the main ingestion pathway. In this study, we estimated the values of activity concentrations in water in the early phase after the accident, using a compartment model as an estimation method. The model uses measurement values of activity concentration and deposition rate of iodine-131 onto the ground, which is calculated from an atmospheric dispersion simulation. The model considers how drinking water would be affected by radionuclides deposited into water. We estimated the activity concentrations of water on Kawamata town and Minamisouma city during March of 2011 and the committed effective doses were 0.08 mSv and 0.06 mSv. We calculated the transfer parameters in the model for estimating the activity concentrations in the areas with a small amount of measurement data. In addition, we estimated the committed effective doses from vegetables using atmospheric dispersion simulation and FARMLAND model in case of eating certain vegetables as option information.

  10. Comparison of internal radiation doses estimated by MIRD and voxel techniques for a ''family'' of phantoms

    International Nuclear Information System (INIS)

    Smith, T.

    2000-01-01

    The aim of this study was to use a new system of realistic voxel phantoms, based on computed tomography scanning of humans, to assess its ability to specify the internal dosimetry of selected human examples in comparison with the well-established MIRD system of mathematical anthropomorphic phantoms. Differences in specific absorbed fractions between the two systems were inferred by using organ dose estimates as the end point for comparison. A ''family'' of voxel phantoms, comprising an 8-week-old baby, a 7-year-old child and a 38-year-old adult, was used and a close match to these was made by interpolating between organ doses estimated for pairs of the series of six MIRD phantoms. Using both systems, doses were calculated for up to 22 organs for four radiopharmaceuticals with widely differing biodistribution and emission characteristics (technetium-99m pertechnetate, administered without thyroid blocking; iodine-123 iodide; indium-111 antimyosin; oxygen-15 water). Organ dose estimates under the MIRD system were derived using the software MIRDOSE 3, which incorporates specific absorbed fraction (SAF) values for the MIRD phantom series. The voxel system uses software based on the same dose calculation formula in conjunction with SAF values determined by Monte Carlo analysis at the GSF of the three voxel phantoms. Effective doses were also compared. Substantial differences in organ weights were observed between the two systems, 18% differing by more than a factor of 2. Out of a total of 238 organ dose comparisons, 5% differed by more than a factor of 2 between the systems; these included some doses to walls of the GI tract, a significant result in relation to their high tissue weighting factors. Some of the largest differences in dose were associated with organs of lower significance in terms of radiosensitivity (e.g. thymus). In this small series, voxel organ doses tended to exceed MIRD values, on average, and a 10% difference was significant when all 238 organ doses

  11. Survey of food radioactivity and estimation of internal dose from ingestion in China

    International Nuclear Information System (INIS)

    Zhang Jingyuan; Zhu Hongda; Han Peizhen

    1988-01-01

    In order to provide necessary bases for establishing 'Radionuclide Concentration Limits in Food stuffs', survey on radionuclide contents in Chinese food and estimation of internal dose from ingestion were carried out with the cooperation of 30 radiation protection establishments during the period 1982-1986. Activity concentrations in 14 categories (27 kinds) of Chinese food for 22 radionuclides were determined. In the light of three principal types of Chinese diet, food samples were collected from normal radiation background areas in 14 provinces or autonomous regions and three similarly elevated natural background areas. Annual intake by ingestion and resultant committed dose equivalents to general public for 15 radionuclides in these areas were estimated. In normal background areas the total annual intake of the 15 radionuclides by the public (adlut males) is about 4.2 x 10 4 Bq, and the resultant total committed dose equivalent is about 3.43 x 10 -4 Sv, but in two elevated natural background area the public annual intake and resulting committed dose equivalents for some natural radionulides are much higher than those in normal areas, while no obvious radiocontamination was discoveried relative contribution of each food category or each radionuclide to the total are discussed

  12. Internal Mammary Lymph Node Irradiation Contributes to Heart Dose in Breast Cancer

    International Nuclear Information System (INIS)

    Chargari, Cyrus; Castadot, Pierre; MacDermed, Dhara; Vandekerkhove, Christophe; Bourgois, Nicolas; Van Houtte, Paul; Magne, Nicolas

    2010-01-01

    We assessed the impact of internal mammary chain radiotherapy (IMC RT) to the radiation dose received by the heart in terms of heart dose-volume histogram (DVH). Thirty-six consecutive breast cancer patients presenting with indications for IMC RT were enrolled in a prospective study. The IMC was treated by a standard conformal RT technique (50 Gy). For each patient, a cardiac DVH was generated by taking into account the sole contribution of IMC RT. Cardiac HDV were compared according to breast cancer laterality and the type of previous surgical procedure, simple mastectomy or breast conservative therapy (BCT). The contribution of IMC RT to the heart dose was significantly greater for patients with left-sided versus right-sided tumors (13.8% and 12.8% for left-sided tumors versus 3.9% and 4.2% for right-sided tumors in the BCT group and the mastectomy group, respectively; p < 0.0001). There was no statistically significant difference in IMC contribution depending on the initial surgical procedure. IMC RT contributes to cardiac dose for both left-sided and right-sided breast cancers, although the relative contribution is greater in patients with left-sided tumors.

  13. Participation of the Nuclear Regulatory Authority in the 'Third European Intercomparison Exercise on Internal Dose Assessment'

    International Nuclear Information System (INIS)

    Rojo, Ana Maria; Gomez Parada, Ines Maria

    2001-01-01

    This paper resume the participation of the Argentine Nuclear Regulatory Authority (ARN) in the 'Third European Intercomparison Exercise on Internal Dose Assessment'. It takes place during 5 months in 1998 and the final meeting was held in Weimar, Germany, on May 1999. This exercise involved the previous distribution of seven cases, simulated and real, describing possible incorporations of radioactive materials. There was a description of the event, data of retention or excretion measurements and air concentration data. The fifty participants belong to twenty three countries had do solve the cases and informed the results to the organizers, mainly the incorporation and effective dose was required. The objective was to review the methodology, the codes and the different assumptions used by the participants for discussing the consistent of the result. The results are shown through tables including the maximum and minimum values gave for the final report and the results informed by ARN. This exercise allowed to compare the methodology used by the ARN internal dosimetry group with other choose by several international groups to assure that the codes, assumptions and methodology were satisfactory to solve the different cases given by the organizers. (author)

  14. International intercomparison of dose measurements using EPR spectrometry of tooth enamel

    International Nuclear Information System (INIS)

    Wieser, A.; Chumak, V.; Pasalskaya, L.; Pavlenko, J.; Sholom, S.; Bailiff, I.; Baran, N.; Bougai, A.; Kolesnik, S.; Maksimenko, V.; Brik, A.; Matyash, M.; Scherbina, O.; Dubovsky, S.; Kirillov, V.; Minenko, V.; Finin, V.; Haskell, E.; Hayes, R.; Kenner, G.; Ivannikov, A.; Skvortsov, V.; Stepanenko, V.; Liidja, G.; Lippmaa, E.; Past, J.; Puskar, J.; Meijer, A.; Radchuk, V.; Vaher, Ue.

    1996-01-01

    Electron paramagnetic resonance (EPR) dosimetry with teeth is the only solid state dosimetry method that allows for direct measurement of the individual dose. It is considered to be a very promising tool for retrospective individual dosimetry after accidental radioactive releases. It will help to make a reliable assessment of the radiation risk. A number of laboratories are engaged in retrospective EPR dosimetry with teeth. There is consequently a need to develop a programme of intercalibration and intercomparison to check whether the results produced by different laboratories are either consistent or accurate. The Commission of the European Communities has initiated the project ECP10 entitled, Retrospective Dosimetry and Dose reconstruction. Within the joint Eu/CIS project the 1st International Intercomparison of EPR Dosimetry with Teeth' was started in 1994. Nine research laboratories were involved from Germany, Russia, Belarus, Ukraine, Estonia and USA

  15. Development of mathematical pediatric phantoms for internal dose calculations: designs, limitations, and prospects

    International Nuclear Information System (INIS)

    Cristy, M.

    1980-01-01

    Mathematical phantoms of the human body at various ages are employed with Monte Carlo radiation transport codes for calculation of photon specific absorbed fractions. The author has developed a pediatric phantom series based on the design of the adult phantom, but with explicit equations for each organ so that organ sizes and marrow distributions could be assigned properly. Since the phantoms comprise simple geometric shapes, predictive dose capability is limited when geometry is critical to the calculation. Hence, there is a demand for better phantom design in situations where geometry is critical, such as for external irradiation or for internal emitters with low energy photons. Recent advances in computerized axial tomography (CAT) present the potential for derivation of anatomical information, which is so critical to development of phantoms, and ongoing developmental work on compuer architecture to handle large arrays for Monte Carlo calculations should make complex-geometry dose calculations economically feasible within this decade

  16. PUDEQ: a computer code for calculating dose equivalent from internal deposition of plutonium at Hanford

    International Nuclear Information System (INIS)

    Houston, J.R.; Heid, K.R.

    1975-10-01

    Presented here are the procedures and mathematical models used in developing PUDEQ, a computer program for computing the dose equivalent to body organs from intake of Pu. The program was designed specifically to use the data recorded on the Hanford Internal Exposure (HIE) System magnetic tape as input. Insofar as was possible, the recommendations of the Advisory Committee on Dose from Plutonium and other Transuranics was followed. Some deviations were made where errors, omissions, or inconsistencies were found, after consultation with members of the Committee. In the current version of the program only Pu and its immediate important daughters are considered. The program could, however, be expanded to include other transuranic nuclides. At present, only a few depositions of transuranic nuclides other than plutonium are recorded out of about 450 individuals involved in a total of over 700 plutonium intakes

  17. Factors that elevate the internal radionuclide and chemical retention, dose and health risks to infants and children in a radiological-nuclear emergency

    International Nuclear Information System (INIS)

    Richardson, R. B.

    2009-01-01

    The factors that influence the dose and risk to vulnerable population groups from exposure and internal uptake of chemicals are examined and, in particular, the radionuclides released in chemical, biological, radiological, nuclear and explosive events. The paper seeks to identify the areas that would benefit from further research. The intake and body burdens of carbon and calcium were assessed as surrogates for contaminants that either act like or bind to hydrocarbons (e.g. tritium and 14 C) or bone-seeking radionuclides (e.g. 90 Sr and 239 Pu). The shortest turnover times for such materials in the whole body were evaluated for the newborn: 11 d and 0.5 y for carbon and calcium, respectively. However, their biokinetic behaviour is complicated by a particularly high percentage of the gut-absorbed dietary intake of carbon (∼16%) and calcium (∼100%) that is incorporated into the soft tissue and skeleton of the growing neonate. The International Commission on Radiological Protection dose coefficients (Sv Bq -1 ) were examined for 14 radionuclides, including 9 of concern because of their potential use in radiological dispersal devices. The dose coefficients for a 3-month-old are greater than those for adults (2-56 times more for ingestion and 2-12 times for inhalation). The age-dependent dose and exposure assessment of contaminant intakes would improve by accounting for gender and growth where it is currently neglected. Health risk is evaluated as the product of the exposure and hazard factors, the latter being about 10-fold greater in infants than in adults. The exposure factor is also approximately 10-fold higher for ingestion by infants than by adults, and unity for inhalation varying with the contaminant. Qualitative and quantitative physiological and epidemiological evidence supports infants being more vulnerable to cancer and neurological deficit than older children). (authors)

  18. Internal dose evaluation from actinide intakes during nuclear power reactor spent fuel reprocessing

    International Nuclear Information System (INIS)

    Pawar, S.K.; Kumar, Ranjeet; Gamre, Rupali; Purohit, R.G.

    2011-01-01

    Full text: Indian PHWR reactors are using natural uranium as fuel. After use they are discharged from the core and send for fuel reprocessing to extract the unused uranium and plutonium. Plutonium and other actinides are formed by activation of 238 U with neutrons and subsequent decay. During reprocessing of the spent fuel, major long lived actinides (Pu, Am and U) may become radiological safety hazard. Actinides intakes are more probable during declading and chopping of spent fuel. During routine plant operation in reprocessing, exposure to Pu is a major concern along with Am and U in working environment due to its higher radiological hazard and occupational workers are likely to get exposed to plutonium, Americium and Uranium mostly through inhalation. Internally deposited Pu-isotopes, Am-isotope and U-isotopes are estimated using techniques such as lung counting (in-vivo) and urine and faecal bioassay (in-vitro). Evaluation of internal dose of actinides is dependent upon urinary excreted activity. To estimate the internally deposited Pu, U and Am at an intake level of about one ALI (ICRP-78, 1997) of occupational workers, urine bioassay is the preferred technique due to high detection sensitivity, ease of sample handling and economical method. A small and measurable fraction of internally deposited Pu, Am and U are excreted through urine whose content is dependent on time of inhalation, quantity and type of chemical form of inhaled material (S and M class). A standardized radiochemical analysis method for separation and estimation of Pu, Am and U is used to evaluate the urinary excreted activity and internal dose. Several measurements techniques are employed for the estimation of plutonium, Americium and Uranium for example, Alpha Spectrometry, Gamma Spectrometry, Neutron Activation Analysis, Mass Spectrometry and Fission Track Analysis. The radiochemical separation followed by alpha counting and/or spectrometry is chosen due to its ease of handling and

  19. Internal dose assessment in a case of continuous intake of Cs 137

    International Nuclear Information System (INIS)

    Gomez Parada, I.; Rojo, A.M.

    2000-01-01

    In 1997 the Argentine Nuclear Regulatory Authority (ARN) was invited to participate in the '3rd. European Intercomparison Exercise on Internal Dose Assessment'. This paper presents the solution submitted by the ARN to one of the cases proposed in the exercise. This is a real case of continuous ingestion of cesium 137 due to the environmental contamination arising from the Chernobyl accident. The subject was member of the public and the results of whole body counter measurements were provided. The monitoring period spanned from the first month after the accident to approximately 880 days later. The solution implied to estimate the total intake for the accident until the end of the monitoring period, the effective dose received by the subject in 1986 and 1987 respectively and the committed effective dose due to the total intake. For the intake assessment the code Cindy v 1.4 was used, assuming a constant rate of intake during the whole period of intake. The systemic retention model for caesium was that of the ICRP 30, with a modified biological half-life of the long-term retention. The dates of the beginning and end of the period of intake were chosen, using the same software, looking for the ones that fits better to the measurements data. This rate of intake and the same metabolic models used for the intake assessment were the input to the CINDY code to find the dose received by the subject in 1986 and 1987 respectively, as well as the committed effective dose. An alternative dose assessment was made, directly from body burden measurements, in order to compare the obtained values. In this approach, the software Origin 4.0 was used to graph the whole body activity measurements and the integrate it for the desired time intervals. Applying the corresponding Specific Effective Energy value obtained from LUPED 2.06 for the reference man, the effective doses were obtained directly from body burden. It was found that the values for the effective doses were almost the same

  20. Full system decontamination for dose reduction at the preventive maintenance work of the reactor core internals

    International Nuclear Information System (INIS)

    Sato, Y.; Inami, I.; Suzuki, N.; Fujimori, A.; Wille, H.

    2000-01-01

    At the Fukushima Dai-ichi Nuclear Power Station unit 3 and unit 2 of Tokyo Electric Power Company (TEPCO), the replacement of the core shroud and internals have been conducted respectively in the FY 1997 outage and in the FY 1998 outage. The replacement of the welded core internals in operating BWR plants is the first time in the world as complete countermeasure to improve SCC resistance. At present both units are operating smoothly. The developed technology concept is to restore those internals in air inside the reactor pressure vessel. To reduce the radiation dose rate inside the RPV, not only a shielding method was applied to cut the radiation from the irradiated structures but also a chemical decontamination method was applied to dissolve the radioactive crud deposit on the surface by using chemical agents. The CORD UV process was applied for this Full System Decontamination including operating the reactor recirculation pumps. The critical pass time required was approximately 7 days for each unit. In both units the radioactivity of 10 TBq (280 Ci) and the Fe, Ni, Cr crud of 60-70 kg as metal in total was dissolved and removed by 5 m 3 (175 ft 3 ) ion exchange resins as only waste generated. The obtained decontamination factor (DF) at the RPV bottom reached 40-100. As result, the dose rate decreased to approximately 0.1 mSv/h under water. Before and after the installation of the in-vessel shielding, a mechanical cleaning was extensively applied inside the RPV to remove the residual crud as well as the cutting particles. As result, the RPV bottom dose rate decreased further to 0.03 mSv/h under water and 0.2 mSv/h in air. A better working environment for human access than expected was established inside the RPV, resulting the 70, 140 man*Sv saving respectively at unit 3 (1F-3) and unit 2 (1F-2). (author)

  1. Calibration factor or calibration coefficient?

    International Nuclear Information System (INIS)

    Meghzifene, A.; Shortt, K.R.

    2002-01-01

    Full text: The IAEA/WHO network of SSDLs was set up in order to establish links between SSDL members and the international measurement system. At the end of 2001, there were 73 network members in 63 Member States. The SSDL network members provide calibration services to end-users at the national or regional level. The results of the calibrations are summarized in a document called calibration report or calibration certificate. The IAEA has been using the term calibration certificate and will continue using the same terminology. The most important information in a calibration certificate is a list of calibration factors and their related uncertainties that apply to the calibrated instrument for the well-defined irradiation and ambient conditions. The IAEA has recently decided to change the term calibration factor to calibration coefficient, to be fully in line with ISO [ISO 31-0], which recommends the use of the term coefficient when it links two quantities A and B (equation 1) that have different dimensions. The term factor should only be used for k when it is used to link the terms A and B that have the same dimensions A=k.B. However, in a typical calibration, an ion chamber is calibrated in terms of a physical quantity such as air kerma, dose to water, ambient dose equivalent, etc. If the chamber is calibrated together with its electrometer, then the calibration refers to the physical quantity to be measured per electrometer unit reading. In this case, the terms referred have different dimensions. The adoption by the Agency of the term coefficient to express the results of calibrations is consistent with the 'International vocabulary of basic and general terms in metrology' prepared jointly by the BIPM, IEC, ISO, OIML and other organizations. The BIPM has changed from factor to coefficient. The authors believe that this is more than just a matter of semantics and recommend that the SSDL network members adopt this change in terminology. (author)

  2. Development of wireless communication system in real-time internal radiation dose measurement system using magnetic field

    International Nuclear Information System (INIS)

    Sato, Fumihiro; Shinohe, Kohta; Takura, Tetsuya; Matsuki, Hidetoshi; Yamada, Syogo; Sato, Tadakuni

    2009-01-01

    In radiation therapy, excessive radiation occurs because the actual delivered dose to the tumor is unknown. To overcome this problem, we need a system in which the delivered dose is measured inside the body, and the dose data are transmitted from the inside to the outside of the body. In this study, a wireless communication system, using magnetic fields was studied, and an internal circuit for obtaining radiation dose data from an x-ray detector was examined. As a result, a communication distance of 200 mm was obtained. An internal circuit was developed, and a signal transmission experiment was performed using the wireless communication system. As a result, the radiation dose data from an x-ray detector was transmitted over a communication distance of 200 mm, and the delivered dose was determined from the received signal

  3. Atmospheric Extinction Coefficients in the Ic Band for Several Major International Observatories: Results from the BiSON Telescopes, 1984-2016

    Science.gov (United States)

    Hale, S. J.; Chaplin, W. J.; Davies, G. R.; Elsworth, Y. P.; Howe, R.; Lund, M. N.; Moxon, E. Z.; Thomas, A.; Pallé, P. L.; Rhodes, E. J., Jr.

    2017-09-01

    Over 30 years of solar data have been acquired by the Birmingham Solar Oscillations Network (BiSON), an international network of telescopes used to study oscillations of the Sun. Five of the six BiSON telescopes are located at major observatories. The observational sites are, in order of increasing longitude: Mount Wilson (Hale) Observatory (MWO), California, USA; Las Campanas Observatory, Chile; Observatorio del Teide, Izaña, Tenerife, Canary Islands; the South African Astronomical Observatory, Sutherland, South Africa; Carnarvon, Western Australia; and the Paul Wild Observatory, Narrabri, New South Wales, Australia. The BiSON data may be used to measure atmospheric extinction coefficients in the {{{I}}}{{c}} band (approximately 700-900 nm), and presented here are the derived atmospheric extinction coefficients from each site over the years 1984-2016.

  4. Method for calculation of upper limit internal alpha dose rates to aquatic organisms with application of plutonium-239 in plankton

    International Nuclear Information System (INIS)

    Paschoa, A.S.; Baptista, G.B.

    1977-01-01

    A method for the calculation of upper limit internal alpha dose rates to aquatic organisms is presented. The mean alpha energies per disintegration of radionuclides of interest are listed to be used in standard methodologies to calculate dose to aquatic biota. As an application, the upper limits for the alpha dose rates from 239 Pu to the total body of plankton are estimated based on data available in open literature [pt

  5. Comparison of normal tissue dose with three-dimensional conformal techniques for breast cancer irradiation including the internal mammary nodes

    NARCIS (Netherlands)

    van der Laan, Hans Paul; Dolsma, Willemtje; van t Veld, Aart; Bijl, HP; Langendijk, JA

    2005-01-01

    PURPOSE: To compare the Para Mixed technique for irradiation of the internal mammary nodes (IMN) with three commonly used strategies, by analyzing the dose to the heart and other organs at risk. METHODS AND MATERIALS: Four different three-dimensional conformal dose plans were created for 30 breast

  6. Literature study of the radiobiological parameters of Caesium-137 required for evaluating internal irradiation doses as a function of age

    International Nuclear Information System (INIS)

    Garnier, A.

    1968-01-01

    This document reassembles information published in scientific literature on radiobiological parameters of Cs-137, necessary for the estimate of the internal irradiation dose of man according to his age (during growth). The data are completed by a commented review of the mathematical models, proposed in order to value the irradiation doses from ingested cesium and the biological parameters. (author) [fr

  7. Fluence-to-absorbed-dose conversion coefficients for neutron beams from 0.001 eV to 100 GeV calculated for a set of pregnant female and fetus models

    International Nuclear Information System (INIS)

    Taranenko, Valery; Xu, X George

    2008-01-01

    Protection of fetuses against external neutron exposure is an important task. This paper reports a set of absorbed dose conversion coefficients for fetal and maternal organs for external neutron beams using the RPI-P pregnant female models and the MCNPX code. The newly developed pregnant female models represent an adult female with a fetus including its brain and skeleton at the end of each trimester. The organ masses were adjusted to match the reference values within 1%. For the 3 mm cubic voxel size, the models consist of 10-15 million voxels for 35 organs. External monoenergetic neutron beams of six standard configurations (AP, PA, LLAT, RLAT, ROT and ISO) and source energies 0.001 eV-100 GeV were considered. The results are compared with previous data that are based on simplified anatomical models. The differences in dose depend on source geometry, energy and gestation periods: from 20% up to 140% for the whole fetus, and up to 100% for the fetal brain. Anatomical differences are primarily responsible for the discrepancies in the organ doses. For the first time, the dependence of mother organ doses upon anatomical changes during pregnancy was studied. A maximum of 220% increase in dose was observed for the placenta in the nine months model compared to three months, whereas dose to the pancreas, small and large intestines decreases by 60% for the AP source for the same models. Tabulated dose conversion coefficients for the fetus and 27 maternal organs are provided

  8. The choice of a biological model in assessing internal dose equivalent

    International Nuclear Information System (INIS)

    Parodo, A.; Erre, N.

    1977-01-01

    Many are the biological models related to kinetic behavior of radioactive materials within the organism, or in an organ. This is true particularly for the metabolic kinetics of bone-seekers radionuclides described differently by various authors: as a consequence, different forms of the retention function have been used in calculating internal dose equivalent. In our opinion, the retention functions expressed as linear combinations of exponential terms with negative exponents are preferable. In fact, they can be obtained by coherent compartmental analysis and allow a mathematical formalism fairly well definite and easily adaptable to computers. Moreover, it is possible to make use of graphs and monograms already published. The role of the biological model in internal dosimetry, referred to the reliability of the quantitative informations on the kinetic behavior of the radionuclides in the organism and, therefrom, to the accuracy of the doses calculated, is discussed. By comparing the results obtained with different biological models, one finds that the choice of a model is less important than the choice of the value of the appropriate parameters

  9. Application of the International Life Sciences Institute Key Events Dose-Response Framework to food contaminants.

    Science.gov (United States)

    Fenner-Crisp, Penelope A

    2012-12-01

    Contaminants are undesirable constituents in food. They may be formed during production of a processed food, present as a component in a source material, deliberately added to substitute for the proper substance, or the consequence of poor food-handling practices. Contaminants may be chemicals or pathogens. Chemicals generally degrade over time and become of less concern as a health threat. Pathogens have the ability to multiply, potentially resulting in an increased threat level. Formal structures have been lacking for systematically generating and evaluating hazard and exposure data for bioactive agents when problem situations arise. We need to know what the potential risk may be to determine whether intervention to reduce or eliminate contact with the contaminant is warranted. We need tools to aid us in assembling and assessing all available relevant information in an expeditious and scientifically sound manner. One such tool is the International Life Sciences Institute (ILSI) Key Events Dose-Response Framework (KEDRF). Developed as an extension of the WHO's International Program on Chemical Safety/ILSI mode of action/human relevance framework, it allows risk assessors to understand not only how a contaminant exerts its toxicity but also the dose response(s) for each key event and the ultimate outcome, including whether a threshold exists. This presentation will illustrate use of the KEDRF with case studies included in its development (chloroform and Listeriaonocytogenes) after its publication in the peer-reviewed scientific literature (chromium VI) and in a work in progress (3-monochloro-1, 2-propanediol).

  10. Estimating dose rates to organs as a function of age following internal exposure to radionuclides

    International Nuclear Information System (INIS)

    Leggett, R.W.; Eckerman, K.F.; Dunning, D.E. Jr.; Cristy, M.; Crawford-Brown, D.J.; Williams, L.R.

    1984-03-01

    The AGEDOS methodology allows estimates of dose rates, as a function of age, to radiosensitive organs and tissues in the human body at arbitrary times during or after internal exposure to radioactive material. Presently there are few, if any, radionuclides for which sufficient metabolic information is available to allow full use of all features of the methodology. The intention has been to construct the methodology so that optimal information can be gained from a mixture of the limited amount of age-dependent, nuclide-specific data and the generally plentiful age-dependent physiological data now available. Moreover, an effort has been made to design the methodology so that constantly accumulating metabolic information can be incorporated with minimal alterations in the AGEDOS computer code. Some preliminary analyses performed by the authors, using the AGEDOS code in conjunction with age-dependent risk factors developed from the A-bomb survivor data and other studies, has indicated that the doses and subsequent risks of eventually experiencing radiogenic cancers may vary substantially with age for some exposure scenarios and may be relatively invariant with age for other scenarios. We believe that the AGEDOS methodology provides a convenient and efficient means for performing the internal dosimetry

  11. Estimated fluence-to-absorbed dose conversion coefficients for use in radiological protection of embryo and foetus against external exposure to photons from 50 keV to 10 GeV

    International Nuclear Information System (INIS)

    Chen, J.

    2006-01-01

    In the literature, no conversion coefficients are available for use in radiological protection of the embryo and foetus against external exposure to photons. This study used the Monte-Carlo code MCNPX to determine mean absorbed doses to the embryo and foetus when the mother is exposed to external photon fields. Monoenergetic photons ranging from 50 keV to 10 GeV were considered. The irradiation geometries included antero-posterior (AP), postero-anterior (PA), lateral (LAT), rotational (ROT), and isotropic (ISO). At each of these standard irradiation geometries, absorbed doses to the foetal brain and body were calculated for the embryo of 8 weeks and the foetus of 3, 6 or 9 months. Photon fluence-to-absorbed-dose conversion coefficients were estimated for the four prenatal ages. (authors)

  12. Fluence-to-absorbed dose conversion coefficients for use in radiological protection of embryo and foetus against external exposure to protons from 100 MeV to 100 GeV

    International Nuclear Information System (INIS)

    Chen, J.

    2006-01-01

    In the literature, no conversion coefficients are available for use in radiological protection of embryo and foetus against external exposure to protons. This study used the Monte Carlo code MCNPX to determine mean absorbed doses to the embryo and foetus when the mother is exposed to proton fields. Monoenergetic protons ranging from 100 MeV to 100 GeV were considered. The irradiation geometries include antero-posterior (AP), postero-anterior (PA), lateral (LAT), rotational (ROT) and isotropic (ISO). At each of these standard irradiation geometries, absorbed doses to the foetal brain and body were calculated for the embryo of 8 weeks and the foetus of 3, 6 or 9 months. Proton fluence-to-absorbed dose conversion coefficients were derived for the four prenatal ages. (authors)

  13. Fluence-to-Absorbed Dose Conversion Coefficients for Use in Radiological Protection of Embryo and Foetus Against External Exposure to Muons from 20MeV to 50GeV

    International Nuclear Information System (INIS)

    Chen Jing

    2008-01-01

    This study used the Monte-Carlo code MCNPX to determine mean absorbed doses to the embryo and foetus when the mother is exposed to external muon fields. Monoenergetic muons ranging from 20 MeV to 50 GeV were considered. The irradiation geometries include anteroposterior (AP), postero-anterior (PA), lateral (LAT), rotational (ROT), isotropic (ISO), and top-down (TOP). At each of these irradiation geometries, absorbed doses to the foetal body were calculated for the embryo of 8 weeks and the foetus of 3, 6 or 9 months, respectively. Muon fluence-to-absorbed-dose conversion coefficients were derived for the four prenatal ages. Since such conversion coefficients are yet unknown, the results presented here fill a data gap

  14. Estimation of Internal Radiation Dose to Nuclear Medicine Workers at Siriraj Hospital

    International Nuclear Information System (INIS)

    Asawarattanapakdee, J.; Sritongkul, N.; Chaudakshetrin, P.; Kanchanaphiboon, P.; Tuntawiroon, M.

    2012-01-01

    Every type of work performed in a nuclear medicine department will make a contribution to both external and internal exposure of the worker. The purpose of this study is to evaluate the potential risks of internal contamination to staff members during nuclear medicine practices and to conclude about the requirement of a routine internal monitoring. Following the method describes in the ICRP Publication 78 and the IAEA Safety Standard Series No. RS- G-1.2, in vivo thyroid bioassays using NaI(Tl) thyroid probe were performed to determine the intake estimates on 7 groups of nuclear medicine personnel working with I-131 and Tc-99m, based on working conditions and amount of radionuclides being handled. Frequency of measurements was between 7 and 14 days. These include (1) physicians and physicists, (2) radiochemists (3) technologists, (4) nurses and assistant nurses, (5) imaging room assistants, (6) hot lab workers and (7) hospital ward housekeepers/cleaners. Among all workers, the intake estimates of I-131 in the thyroid ranged from 0 to 76.7 kBq and of the technetium-99m from 0 to 35.4 MBq. The mean committed effective dose equivalent (CEDE) from both I-131 and Tc-99m were 0.63, 1.44 0.53, 0.57, 0.73, 0.98, and 1.36, mSv, for group 1 through group 7 respectively. However, the highest mean CEDE of 1.44 (max. 1.75) and 1.36 (max. 2.11) mSv observed in groups of radiochemists and hospital ward housekeepers were within the permissible level. Our results showed that CEDE for internal exposure in this study were less than investigate level of 5 mSv according to the ICRP Publication 78 and the IAEA Basic Safety Standards. However, the mean CEDE for radiochemists and hospital ward housekeepers were considered in exceed of the limits of recording level (1 mSv).The increasing use of I-131 and Tc-99m in nuclear medicine poses significant risks of internal exposure to the staff. This study suggests that a routine monitoring program for internal exposures should be implemented for

  15. Proceedings of an international workshop on historic dose experience and dose reduction (ALARA) at nuclear power plants

    International Nuclear Information System (INIS)

    Horan, J.R.; Baum, J.W.; Dionne, B.J.

    1985-06-01

    Dose reduction data and experience from 28 foreign and 10 US nuclear power plants was examined to determine causes for the wide variations in occupational dose from country to country. Major topics discussed were: steam generator and refueling maintenance problems; utility and supplier ALARA programs; effectiveness of dose-reduction modifications; attitudes and training; current and future dose-reduction research. While many parameters contribute to differences of occupational doses between plants from different nations, it is clear that most US plants have higher collective dose equivalent per reactor per megawatt-year than most other countries, even for plants of similar size and age. Worldwide, Finnish and Swedish plants, both PWR and BWR, have achieved the lowest values. Major factors which contribute to low doses include: (1) minimization of cobalt in primary system components exposed to water; (2) careful plant design, layout and component segregation and shielding; (3) plant standardization; (4) selection of components and systems for increased reliability; (5) management interest and commitment; (6) minimum number of workers and in-depth worker training; (7) careful control of primary system oxygen and pH; (8) good primary system water purity to minimize corrosion product formation; (9) use of special tools and robotics; (10) decontamination and passivation of primary systems and components; and (11) extent of backfitting and mandated inspections

  16. Neutron dose study with bubble detectors aboard the International Space Station as part of the Matroshka-R experiment

    International Nuclear Information System (INIS)

    Machrafi, R.; Garrow, K.; Ing, H.; Smith, M. B.; Andrews, H. R.; Akatov, Yu; Arkhangelsky, V.; Chernykh, I.; Mitrikas, V.; Petrov, V.; Shurshakov, V.; Tomi, L.; Kartsev, I.; Lyagushin, V.

    2009-01-01

    As part of the Matroshka-R experiments, a spherical phantom and space bubble detectors (SBDs) were used on board the International Space Station to characterise the neutron radiation field. Seven experimental sessions with SBDs were carried out during expeditions ISS-13, ISS-14 and ISS-15. The detectors were positioned at various places throughout the Space Station, in order to determine dose variations with location and on/in the phantom in order to establish the relationship between the neutron dose measured externally to the body and the dose received internally. Experimental data on/in the phantom and at different locations are presented. (authors)

  17. Soil-plant-relationships and ecological forecast of human internal doses from long-lived radionuclides. Dose 'cost' of the transformation of radionuclides bioavailability

    International Nuclear Information System (INIS)

    Kravets, A.P.; Grodzinsky, D.M.

    1999-01-01

    Soil pathway of radionuclides pollution of agricultural production becomes the main one at the recovery stage of postaccidental period. For this stage dynamics of the human foodstuffs cleaning and rate of internal dose due to consumption are results , of the interaction of three main factors, namely, the rate of the decrease of soil contamination, structure of soil use and transformations of bioavailability of radionuclides. Representation of these ideas in quantitative form, documentation and analysis of the main ecological causes that determine the intensity of the radionuclides mobility in the biological cycle is essential increase the accuracy of the long-term forecast of human dose formation and promote the development of adequate strategies for countermeasures. General formal model and practical method of the ecological forecast of human internal doses has been proposed and used for estimation. Refs. 5 (author)

  18. Development of internal dose assessment procedure for workers in industries using raw materials containing naturally occurring radioactive materials

    International Nuclear Information System (INIS)

    Choi, Cheol Kyu; KIm, Yong Geon; Ji, Seung Woo; Kim, Kwang Pyo; Koo, Bon Cheol; Chang, Byung Uck

    2016-01-01

    It is necessary to assess radiation dose to workers due to inhalation of airborne particulates containing naturally occurring radioactive materials (NORM) to ensure radiological safety required by the Natural Radiation Safety Management Act. The objective of this study is to develop an internal dose assessment procedure for workers at industries using raw materials containing natural radionuclides. The dose assessment procedure was developed based on harmonization, accuracy, and proportionality. The procedure includes determination of dose assessment necessity, preliminary dose estimation, airborne particulate sampling and characterization, and detailed assessment of radiation dose. The developed dose assessment procedure is as follows. Radioactivity concentration criteria to determine dose assessment necessity are 10 Bq·g-1 for 40K and 1 Bq·g-1 for the other natural radionuclides. The preliminary dose estimation is performed using annual limit on intake (ALI). The estimated doses are classified into 3 groups (<0.1 mSv, 0.1-0.3 mSv, and >0.3 mSv). Air sampling methods are determined based on the dose estimates. Detailed dose assessment is performed using air sampling and particulate characterization. The final dose results are classified into 4 different levels (<0.1 mSv, 0.1-0.3 mSv, 0.3-1 mSv, and >1 mSv). Proper radiation protection measures are suggested according to the dose level. The developed dose assessment procedure was applied for NORM industries in Korea, including coal combustion, phosphate processing, and monazite handing facilities. The developed procedure provides consistent dose assessment results and contributes to the establishment of optimization of radiological protection in NORM industries

  19. Development of internal dose assessment procedure for workers in industries using raw materials containing naturally occurring radioactive materials

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Cheol Kyu; KIm, Yong Geon; Ji, Seung Woo; Kim, Kwang Pyo [College of Engineering, Kyung Hee University, Yongin (Korea, Republic of); Koo, Bon Cheol; Chang, Byung Uck [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2016-09-15

    It is necessary to assess radiation dose to workers due to inhalation of airborne particulates containing naturally occurring radioactive materials (NORM) to ensure radiological safety required by the Natural Radiation Safety Management Act. The objective of this study is to develop an internal dose assessment procedure for workers at industries using raw materials containing natural radionuclides. The dose assessment procedure was developed based on harmonization, accuracy, and proportionality. The procedure includes determination of dose assessment necessity, preliminary dose estimation, airborne particulate sampling and characterization, and detailed assessment of radiation dose. The developed dose assessment procedure is as follows. Radioactivity concentration criteria to determine dose assessment necessity are 10 Bq·g-1 for 40K and 1 Bq·g-1 for the other natural radionuclides. The preliminary dose estimation is performed using annual limit on intake (ALI). The estimated doses are classified into 3 groups (<0.1 mSv, 0.1-0.3 mSv, and >0.3 mSv). Air sampling methods are determined based on the dose estimates. Detailed dose assessment is performed using air sampling and particulate characterization. The final dose results are classified into 4 different levels (<0.1 mSv, 0.1-0.3 mSv, 0.3-1 mSv, and >1 mSv). Proper radiation protection measures are suggested according to the dose level. The developed dose assessment procedure was applied for NORM industries in Korea, including coal combustion, phosphate processing, and monazite handing facilities. The developed procedure provides consistent dose assessment results and contributes to the establishment of optimization of radiological protection in NORM industries.

  20. Valdose program: methodologies for dose assessment in internal contamination, 1997 census; Programma valdose: metodologie di valutazione della dose da contaminazione interna, censimento 1997

    Energy Technology Data Exchange (ETDEWEB)

    Castellani, C.M.; Battisti, P.; Tarroni, G. [ENEA, Centro Ricerche `Ezio Clementel`, Bologna (Italy). Dip. Ambiente

    1998-12-31

    Dose assessment in internal dosimetry needs computational and interpretative tools that allow carrying out, as a first step, an evaluation of intake on the base of bioassay measurements or WBC measurements, and as a second step, dose evaluation on the base of estimated intake. In the frame of the MIDIA Co-ordination (WBC operating in Italy), in the first months of 1997 a census on methodologies for dose evaluation in internal contamination has been proposed. A technical form has been sent to all the WBC Centres allowing an accurate description of modalities used in each centre. 9 out of 17 centres sent the answers to the technical form in time. In this paper all the forms filled in are reported. A careful comparative evaluation of the answers has been made both for routine monitoring and for special monitoring. The various radionuclides present in the Italian reality, calculation methodologies both for intake and dose, hypotheses adopted for date, path and modalities of contaminations are also presented. Proposals for conforming to the methodology in Italy after the introduction of the models following ICRP 60 publication that are the base of the Euratom 96/29 Directive are also discussed. [Italiano] La valutazione di dose in contaminazione interna necessita di strumenti interpretativi che permettano di effettuare in una prima la valutazione dell`intake sulla base delle misure dei campioni biologici o del corpo intero (WBC), ed in una seconda fase la valutazione della dose sulla base dell`intake. All`interno del coordinamento MIDIA dei WBC operanti in Italia e` stato proposto, nel primo trimestre del 1997, un censimento sulle metodologie di valutazione di dose da contaminazione interna. Ai diversi centri e` stato inviato una scheda tecnica che, mediante un particolareggiato schema di domande, aiutava i diversi centri nella esposizione delle modalita` di valutazione di dose che ogni centro segue. 9 au 17 centri WBC operanti al momemnto in Italia hanno inviato la

  1. Internal radiation dose of KURRI volunteers working at evacuation shelters after TEPCO's Fukushima Daiichi nuclear power plant accident

    International Nuclear Information System (INIS)

    Kurihara, Kouta; Kinashi, Yuko; Okamoto, Kenichi

    2012-01-01

    We report the radiation doses encountered by 59 Kyoto University Research Reactor Institute (KURRI) staff members who had been dispatched to screen refugees for radiation at emergency evacuation sites 45–80 km from the Tokyo Electric Power Co.’s (TEPCO’s) Fukushima Daiichi nuclear power plant. From March 20 to April 30, 2011, 42 members in teams consisting of 2–4 staff members were dispatched 15 times to 7 emergency evacuation sites located 45–80 km from the power plant to examine the radioactive contamination affecting refugees. Continuously, from May 10 to May 23, 2011, 17 members in teams consisting of 2–5 staff members were dispatched 6 times to Fukushima Prefecture to establish the Kyoto University Radiation Mapping (KURAMA) system. Internal burdens of radioactive nuclides were estimated using a whole-body counter consisting of an iron room, NaI (Tl) scintillation detectors, and a digital multichannel analyzer (MCA7600; Seiko EG and G). The calibration of the whole-body counter and the conversion of the measured body burden to the committed effective dose by internal exposure were carried out in accordance with the Nuclear Safety Research Association (NSRA) technical manual. The external radiation dose to each staff member was measured using a personal dosimeter. The first dispatched team showed 1300–1929 Bq of internal radiation activity from cesium (including "1"3"7Cs and "1"3"4Cs) and 48–118 Bq of "1"3"1I. The internal doses of four members of the first team were estimated to be 24–39 μSv. The doses from internal exposure were almost similar to the cumulative external doses for the dispatch period (March 20–22, 2011) when the radiation plumes following the explosions of Units 1 and 3 in TEPCO’s Fukushima Daiichi nuclear plant had diffused around Fukushima City. The external radiation doses of members dispatched after the second team had decreased from one-third to less than one-tenth of the external doses of the first dispatched team

  2. Internal radiation dose of KURRI volunteers working at evacuation shelters after TEPCO's Fukushima Daiichi nuclear power plant accident

    International Nuclear Information System (INIS)

    Kurihara, Kouta; Kinashi, Yuko; Okamoto, Kenichi

    2013-01-01

    We report the radiation doses encountered by 59 Kyoto University Research Reactor Institute (KURRI) staff members who had been dispatched to screen refugees for radiation at emergency evacuation sites 45-80 km from the Tokyo Electric Power Co.'s (TEPCO's) Fukushima Daiichi nuclear power plant. From March 20 to April 30, 2011, 42 members in teams consisting of 2-4 staff members were dispatched 15 times to 7 emergency evacuation sites located 45-80 km from the power plant to examine the radioactive contamination affecting refugees. Continuously, from May 10 to May 23, 2011, 17 members in teams consisting of 2-5 staff members were dispatched 6 times to Fukushima Prefecture to establish the Kyoto University Radiation Mapping (KURAMA) system. Internal burdens of radioactive nuclides were estimated using a whole-body counter consisting of an iron room, NaI (Tl) scintillation detectors, and a digital multichannel analyzer (MCA7600; Seiko EG and G). The calibration of the whole-body counter and the conversion of the measured body burden to the committed effective dose by internal exposure were carried out in accordance with the Nuclear Safety Research Association (NSRA) technical manual. The external radiation dose to each staff member was measured using a personal dosimeter. The first dispatched team showed 1300-1929 Bq of internal radiation activity from cesium (including "1"3"7Cs and "1"3"4Cs) and 48-118 Bq of "1"3"1I. The internal doses of four members of the first team were estimated to be 24-39 μSv. The doses from internal exposure were almost similar to the cumulative external doses for the dispatch period (March 20-22, 2011) when the radiation plumes following the explosions of Units 1 and 3 in TEPCO's Fukushima Daiichi nuclear plant had diffused around Fukushima City. The external radiation doses of members dispatched after the second team had decreased from one-third to less than one-tenth of the external doses of the first dispatched team. The internal

  3. Transfer coefficients for the prediction of the dose to man via the forage-cow-milk pathway from radionuclides released to the biosphere

    International Nuclear Information System (INIS)

    Ng, Y.C.; Colsher, C.S.; Quinn, D.J.; Thompson, S.E.

    1977-01-01

    This document presents tables of diet-to-milk transfer coefficients for radioactive and stable isotopes in the cow. The values are based on an extensive literature review of the secretion of radioisotopes in milk and the concentrations of radioactive or stable isotopes in milk and feed. Transfer coefficients were compiled and tabulated for isotopes of more than 70 elements. The values are summarized in a table of elemental transfer coefficients and also organized into separate tables that reveal their elemental systematics and the effects of physical and chemical form

  4. Transfer coefficients for the prediction of the dose to man via the forage-cow-milk pathway from radionuclides released to the biosphere

    Energy Technology Data Exchange (ETDEWEB)

    Ng, Y C; Colsher, C S; Quinn, D J; Thompson, S E

    1977-07-15

    This document presents tables of diet-to-milk transfer coefficients for radioactive and stable isotopes in the cow. The values are based on an extensive literature review of the secretion of radioisotopes in milk and the concentrations of radioactive or stable isotopes in milk and feed. Transfer coefficients were compiled and tabulated for isotopes of more than 70 elements. The values are summarized in a table of elemental transfer coefficients and also organized into separate tables that reveal their elemental systematics and the effects of physical and chemical form.

  5. A method for rapid estimation of internal dose to members of the public from inhalation of mixed fission products (based on the ICRP 1994 human respiratory tract model for radiological protection)

    International Nuclear Information System (INIS)

    Hou Jieli

    1999-01-01

    Based on the computing principle given in ICRP-30, a method had been given by the author for fast estimating internal dose from an intake of mixed fission products after nuclear accident. Following the ICRP-66 Human respiratory tract model published in 1994, the method was reconstructed. The doses of 1 Bq intake of mixed fission products (its AMAD = 1 μm, decay rate coefficient n = 0.2∼2.0) during the period of 1∼15 d after an accident were calculated. It is lower slightly based on ICRP 1994 respiratory tract model than that based on ICRP-30 model

  6. Internal dose assessments: Uncertainty studies and update of ideas guidelines and databases within CONRAD project

    International Nuclear Information System (INIS)

    Marsh, J. W.; Castellani, C. M.; Hurtgen, C.; Lopez, M. A.; Andrasi, A.; Bailey, M. R.; Birchall, A.; Blanchardon, E.; Desai, A. D.; Dorrian, M. D.; Doerfel, H.; Koukouliou, V.; Luciani, A.; Malatova, I.; Molokanov, A.; Puncher, M.; Vrba, T.

    2008-01-01

    The work of Task Group 5.1 (uncertainty studies and revision of IDEAS guidelines) and Task Group 5.5 (update of IDEAS databases) of the CONRAD project is described. Scattering factor (SF) values (i.e. measurement uncertainties) have been calculated for different radionuclides and types of monitoring data using real data contained in the IDEAS Internal Contamination Database. Based upon this work and other published values, default SF values are suggested. Uncertainty studies have been carried out using both a Bayesian approach as well as a frequentist (classical) approach. The IDEAS guidelines have been revised in areas relating to the evaluation of an effective AMAD, guidance is given on evaluating wound cases with the NCRP wound model and suggestions made on the number and type of measurements required for dose assessment. (authors)

  7. Use of AERIN code for determining internal doses of transuranic isotopes

    International Nuclear Information System (INIS)

    King, W.C.

    1980-01-01

    The AERIN computer code is a mathematical expression of the ICRP Lung Model. The code was developed at the Lawrence Livermore National Laboratory to compute the body organ burdens and absorbed radiation doses resulting from the inhalation of transuranic isotopes and to predict the amount of activity excreted in the urine and feces as a function of time. Over forty cases of internal exposure have been studied using the AERIN code. The code, as modified, has proven to be extremely versatile. The case studies presented demonstrate the excellent correlation that can be obtained between code predictions and observed bioassay data. In one case study a discrepancy was observed between an in vivo count of the whole body and the application of the code using urine and fecal data as input. The discrepancy was resolved by in vivo skull counts that showed the code had predicted the correct skeletal burden

  8. Intake retention functions and their applications to bioassay and the estimation of internal radiation doses

    International Nuclear Information System (INIS)

    Skrable, K.W.; Chabot, G.E.; French, C.S.; La Bone, T.R.

    1988-01-01

    This paper describes a way of obtaining and gives applications of intake retention functions. These functions give the fraction of an intake of radioactive material expected to be present in a specified bioassay compartment at any time after a single acute exposure or after onset of a continuous exposure. The intake retention functions are derived from a multicompartmental model and a recursive catenary kinetics equation that completely describe the metabolism of radioelements from intake to excretion, accounting for the delay in uptake from compartments in the respiratory and gastrointestinal tracts and the recycling of radioelements between systemic compartments. This approach, which treats excretion as the 'last' compartment of all catenary metabolic pathways, avoids the use of convolution integrals and provides algebraic solutions that can be programmed on hand held calculators or personal computers. The estimation of intakes and internal radiation doses and the use of intake retention functions in the design of bioassay programs are discussed along with several examples

  9. Measurement of the internal dose to families of outpatients treated with {sup 131}I for hyperthyroidism

    Energy Technology Data Exchange (ETDEWEB)

    Barrington, S.F.; O' Doherty, M.J. [St. Thomas' Hospital, PET Imaging Centre, London (United Kingdom); Anderson, P. [Queen Elizabeth Hospital, Department of Nuclear Medicine, Birmingham (United Kingdom); Kettle, A.G. [Kent and Canterbury Hospital, East Kent Hospitals NHS Trust, Department of Nuclear Medicine, Canterbury (United Kingdom); Gadd, R.; Mountford, P.J. [University Hospital of North Staffordshire, Directorate of Medical Physics and Clinical Technology, Stoke-on-Trent (United Kingdom); Thomson, W.H.; Harding, L.K. [City Hospital, Department of Physics and Nuclear Medicine, Birmingham (United Kingdom); Batchelor, S. [Guy' s and St Thomas' Hospital, Department of Medical Physics, London (United Kingdom)

    2008-11-15

    The aim of this study was to measure the internal dose received by family members from ingestion of radioactive contamination after outpatient therapy. Advice was given to minimise transfer of radioiodine. Home visits were made approximately 2, 7 and 21 days after treatment to measure radioactivity in the thyroids of family members. A decay correction was applied to radioactivity detected assuming ingestion had occurred at the earlier contact time, either the day of treatment or the previous home visit. An effective half-life of 6 or 7 days was used depending on age. Thyroid activity was summed if activity was found at more than one visit in excess of the amount attributable to radioactive decay. Effective dose (ED) was calculated using ICRP72. Fifty-three adults and 92 children, median age 12 (range 4-17) years participated. Median administered activity was 576 (range 329-690) MBq {sup 131}I. Thyroid activity ranged from 0 to 5.4 kBq in the adults with activity detected in 17. Maximum adult ED was 0.4 mSv. Thyroid activity ranged from 0 to 11.8 kBq in the children with activity detected in 26. The two highest values of 5.0 and 11.8 kBq occurred in children aged 5 and 14 years from different families. Eighty-five children had no activity or <1 kBq detected. ED was <0.2 mSv in 86 out of 92 children (93%). Previous published data showed 93% of children received an ED {<=}0.8 mSv from external irradiation. With advice, families of outpatients receiving radioiodine should be able to comply with statutory dose limits and constraints. (orig.)

  10. Recent international regulations: low dose-low rate radiation protection and the demise of reason.

    Science.gov (United States)

    Okkalides, Demetrios

    2008-01-01

    The radiation protection measures suggested by the International Committee for Radiation Protection (ICRP), national regulating bodies and experts, have been becoming ever more strict despite the decrease of any information supporting the existence of the Linear no Threshold model (LNT) and of any adverse effects of Low Dose Low Rate (LDLR) irradiation. This tendency arises from the disproportionate response of human society to hazards that are currently in fashion and is unreasonable. The 1 mSv/year dose limit for the public suggested by the ICRP corresponds to a 1/18,181 detriment-adjusted cancer risk and is much lower than other hazards that are faced by modern societies such as e.g. driving and smoking which carry corresponding rate risks of 1/2,100 and 1/2,000. Even worldwide deadly work accidents rate is higher at 1/ 8,065. Such excessive safety measures against minimal risks from man made radiation sources divert resources from very real and much greater hazards. In addition they undermine research and development of radiation technology and tend to subjugate science and the quest for understanding nature to phobic practices.

  11. Radiological dose rate calculations for the International Thermonuclear Experimental Reactor (ITER)

    International Nuclear Information System (INIS)

    Khater, H.Y.; Santoro, R.T.

    1996-01-01

    Two-dimensional biological dose rates were calculated at different locations outside the International Thermonuclear Experimental Reactor (ITER) design. An 18 degree sector of the reactor was modeled in r-θ geometry. The calculations were performed for three different pulsing scenarios. This included a single pulse of 1000 s duration, 10 pulses of 1000 s duration with a 50% duty factor, and 9470 pulses of 1000 s duration with a 50% duty factor for a total fluence of 0.3 MW.a/m 2 . The dose rates were calculated as a function of toroidal angle at locations in the space between the toroidal field (TF) coils and cryostat, and in the space between the cryostat and the biological shield. The two-dimensional results clearly showed the toroidal effect, which is dominated by contribution from the activation of the cryostat and the biological shield. After one pulse, full access to the machine is possible within a few hours following shutdown. After 10 pulses, full access is also possible within the first day following shutdown. At the end of the Basic Performance Phase (BPP), full access is possible at any of the locations considered after one week following shutdown. 5 refs., 5 figs., 2 tabs

  12. Determination of internal radiation dose due to intake of polonium 210 and lead 210 via smoking

    International Nuclear Information System (INIS)

    Al-Masri, M. S.; Kharita, M.H.; Nashawati, A.; Amin, Y.; Al-Akel, B.

    2004-12-01

    In this study, 18 kind of cigarettes and five kinds of molasses consumed by Syrians were collected and analyzed for radioactivity in order to estimate the internal radiation dose caused by 210 Po and 210 Pb intake. Polonium 210 and lead 210 concentrations varied between 4 and 16.4 m Bq/cigarette, while 210 Po distribution ratios in different parts of consumed cigarette were %12, %73, %1.6 in ash, smoke and filter, respectively. In addition, annual intake of 210 Po by a main smoker was varied between 4.4 and 18 Bq/year assuming that the main smoker breathes about 15% of the total 210 Po present in tobacco. Using the values of the annual intake, annual equivalent radiation dose caused by smoking has reached 178 μSv/year. Moreover, mean concentration of 210 Po in nonsmokers and smokers bloods has reached 130 and 97 mBq/l, respectively, while the mean value of 210 Po concentration was relatively higher and reached 176 and 155 mBq/l in smokers and non smoker bloods, respectively (Authors)

  13. Principles of the International Commission on Radiological Protection system of dose limitation

    International Nuclear Information System (INIS)

    Thorne, M.C.

    1987-01-01

    The formulation of a quantitative system of dose limitation based on ICRP principles of 'stochastic' and 'non-stochastic' effects requires that judgements be made on several factors including: relationships between radiation dose and the induction of deleterious effects for a variety of endpoints and radiation types; acceptable levels of risk for radiation workers and members of the public; and methods of assessing whether the cost of introducing protective measures is justified by the reduction in radiation detriment which they will provide. In the case of patients deliberately exposed to ionising radiations, the objectives of radiation protection differ somewhat from those applying to radiation workers and members of the public. For patients, risks and benefits relate to the same person and upper limits on acceptable risks may differ grossly from those appropriate to normal individuals. For these reasons, and because of its historical relationship with the International Congress of Radiology, the ICRP has given special consideration to radiation protection in medicine and has published reports on protection of the patient in diagnostic radiology and in radiation therapy. (author)

  14. Low doses of ionizing radiation: Biological effects and regulatory control. Invited papers and discussions. Proceedings of an international conference

    International Nuclear Information System (INIS)

    1998-01-01

    The levels and biological effects resulting from exposure to ionizing radiation are continuously reviewed by the United Nations Committee on the Effects of Atomic Radiation (UNSCEAR). Since its creation in 1928, the International Commission on Radiological Protection (ICRP) has issued recommendations on protection against ionizing radiation. The UNSCEAR estimates and the ICRP recommendations have served as the basis for national and international safety standards on radiation safety, including those developed by the International Atomic Energy Agency (IAEA) and the World Health Organization (WHO). Concerning health effects of low doses of ionizing radiation, the international standards are based on the plausible assumption that, above the unavoidable background radiation dose, the probability of effects increases linearly with dose, i.e. on a 'linear, no threshold' (LNT) assumption. However, in recent years the biological estimates of health effects of low doses of ionizing radiation and the regulatory approach to the control of low level radiation exposure have been much debated. To foster information exchange on the relevant issues, an International Conference on Low Doses of Ionizing Radiation: Biological Effects and Regulatory Control, jointly sponsored by the IAEA and WHO in co-operation with UNSCEAR, was held from 17-21 November 1997 at Seville, Spain. These Proceedings contain the invited special reports, keynote papers, summaries of discussions, session summaries and addresses presented at the opening and closing of the Conference

  15. External radiation dose and cancer mortality among French nuclear workers. Considering potential confounding by internal radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    Fournier, L.; Laurent, O.; Samson, E.; Caer-Lorho, S.; Laurier, D.; Leuraud, K. [Institute for Radiological Protection and Nuclear Safety, Fontenay aux Roses (France). Ionizing Radiation Epidemiology Lab.; Laroche, P. [AREVA, Paris (France); Le Guen, B. [EDF, Saint Denis (France)

    2016-11-15

    French nuclear workers have detailed records of their occupational exposure to external radiation that have been used to examine associations with subsequent cancer mortality. However, some workers were also exposed to internal contamination by radionuclides. This study aims to assess the potential for bias due to confounding by internal contamination of estimates of associations between external radiation exposure and cancer mortality. A cohort of 59,004 workers employed for at least 1 year between 1950 and 1994 by CEA (Commissariat a l'Energie Atomique), AREVA NC, or EDF (Electricite de France) and badge-monitored for external radiation exposure were followed through 2004 to assess vital status and cause of death. A flag based on a workstation-exposure matrix defined four levels of potential for internal contamination. Standardized mortality ratios were assessed for each level of the internal contamination indicator. Poisson regression was used to quantify associations between external radiation exposure and cancer mortality, adjusting for potential internal contamination. For solid cancer, the mortality deficit tended to decrease as the levels of potential for internal contamination increased. For solid cancer and leukemia excluding chronic lymphocytic leukemia, adjusting the dose-response analysis on the internal contamination indicator did not markedly change the excess relative risk per Sievert of external radiation dose. This study suggests that in this cohort, neglecting information on internal dosimetry while studying the association between external dose and cancer mortality does not generate a substantial bias. To investigate more specifically the health effects of internal contamination, an effort is underway to estimate organ doses due to internal contamination.

  16. External radiation dose and cancer mortality among French nuclear workers: considering potential confounding by internal radiation exposure.

    Science.gov (United States)

    Fournier, L; Laurent, O; Samson, E; Caër-Lorho, S; Laroche, P; Le Guen, B; Laurier, D; Leuraud, K

    2016-11-01

    French nuclear workers have detailed records of their occupational exposure to external radiation that have been used to examine associations with subsequent cancer mortality. However, some workers were also exposed to internal contamination by radionuclides. This study aims to assess the potential for bias due to confounding by internal contamination of estimates of associations between external radiation exposure and cancer mortality. A cohort of 59,004 workers employed for at least 1 year between 1950 and 1994 by CEA (Commissariat à l'Energie Atomique), AREVA NC, or EDF (Electricité de France) and badge-monitored for external radiation exposure were followed through 2004 to assess vital status and cause of death. A flag based on a workstation-exposure matrix defined four levels of potential for internal contamination. Standardized mortality ratios were assessed for each level of the internal contamination indicator. Poisson regression was used to quantify associations between external radiation exposure and cancer mortality, adjusting for potential internal contamination. For solid cancer, the mortality deficit tended to decrease as the levels of potential for internal contamination increased. For solid cancer and leukemia excluding chronic lymphocytic leukemia, adjusting the dose-response analysis on the internal contamination indicator did not markedly change the excess relative risk per Sievert of external radiation dose. This study suggests that in this cohort, neglecting information on internal dosimetry while studying the association between external dose and cancer mortality does not generate a substantial bias. To investigate more specifically the health effects of internal contamination, an effort is underway to estimate organ doses due to internal contamination.

  17. Estimation of internal exposure dose due to Fukushima Daiichi nuclear power plant accidents

    International Nuclear Information System (INIS)

    Morita, Naoko; Takamura, Noboru; Kudo, Takashi; Yamashita, Shunichi; Miura, Miwa; Yoshida, Masahiro; Matsuda, Naoki; Ohtsuru, Akira

    2012-01-01

    Detailed analysis of internal exposure dose in 173 people sent for dealing with the Accident and stayed nearby during the period Mar 11-Apr 10, 2011, was reported. They were 156 men and 17 women, 42.2 years old in average and stayed for average 4.8 days. Analysis was done for following 4 groups of people: in group 1, 45 people had stayed during the period of Mar 11-18 for average 4.3 days; group 2, 66 people during Mar 14-22 for 2.0 days; group 3, 31 people during Mar 28-31 for 5.8 days; and group 4, 31 people during Mar 22-Apr 10 for 10.6 days. Internal radioactivity was measured for 20 min in the whole body counter placed in a low-background, iron-surrounded room in Nagasaki University. The detector was a pair of NaI (Tl) scintillator of 8 in. (diameter) x 4 in. (thickness) equipped at upper and lower portions. Nuclides measured were I-131 (at 0.364 MeV and others), Cs-134 (0.605, 0.796 MeV), Cs-137 (0.662 MeV), of which lowest detection limits were 68 Bq for I, and 28 Bq for Cs. Overall average detection rates of the respective nuclide above were found to be 31.8% (55/173 people), 37.6% (65) and 32.4% (56). In group 1, >800 Bq of the nuclides were found in the body, but in later groups, radioactivity was lower. Detection rate and internal radioactivity were thus found to be highest in those stayed immediately after the Accident. (T.T.)

  18. Dose formation and hematologic effects with prolonged internal exposure of rats by isotope 131I

    International Nuclear Information System (INIS)

    Sova, O.A.; Drozd, Yi.P.

    2013-01-01

    Processes in single dose formation and long-term domestic revenue 131 I in rats was investigated. Original method of estimating absorbed doses in hemacyte for macro-dosemeters indicators was proposed. Dose factors for hemacyte and the dynamics of the blood-forming organs doses for prolonged two cases of prolonged exposure was calculated. Hematologic effects were studied for two variants of entry of the isotope. Peculiarities of doses formation and identified hematological effects are discussed

  19. The issue concerning the use of an annual as opposed to a committed dose limit for internal radiation protection

    International Nuclear Information System (INIS)

    Skrable, K.W.; Chabot, G.E.; Alexander, E.L.; French, C.S.

    1985-01-01

    The scientific, technical, practical, and ethical considerations that relate to the use of an annual as opposed to a committed dose limitation system for internal radiation protection are evaluated and presented. The concerns about problems associated with the more recent ICRP committed dose recommendations that have been expressed by persons who are currently operating under an annual dose limitation system are reviewed and discussed in terms of the radiation protection programme elements that are required for an effective ALARA programme. We include in this and a follow-up article a comparison of how these alternative dose limitation systems affect the economic and professional livelihood of radiation workers and the requirements that they impose upon employers. Finally, we recommend the use of an ICRP based committed dose limitation system that provides protection of workers over an entire occupational lifetime without undue impact on their livelihood and without undue requirements for employers. (author)

  20. Lethal doses of ozone for control of all stages of internal and external feeders in stored products

    DEFF Research Database (Denmark)

    Hansen, Lise S.; Hansen, Peer; Jensen, Karl-Martin V.

    2012-01-01

    Gaseous ozone (O3) has potential for control of insects in stored grain. Previous studies have focused on freely exposed insects. Immatures of internal pests, (e.g. Sitophilus spp. and most stages of Rhyzopertha dominica F.) are protected within kernels and probably require higher doses and....../or longer treatment times for full control. A laboratory study determined the doses of ozone necessary for full control of freely exposed and internal stages of eleven stored product pest species. Test insects were three species of Sitophilus, R. dominica, Tribolium confusum Jacquelin du Val, T. castaneum...

  1. 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

  2. Determination of the conversion coefficient for ambient dose equivalent, H(10), from air kerma measurements; Determinacion del coeficiente de conversion para la dosis equivalente ambiental, H*(10), a partir de mediciones de kerma en aire

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez J, F. [UNAM, Facultad de Ciencias, Circuito Exterior, Ciudad Universitaria, 04510 Ciudad de Mexico (Mexico); Alvarez R, J. T., E-mail: trinidad.alvarez@inin.gob.mx [ININ, Departamento de Metrologia de Radiaciones Ionizantes, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2015-09-15

    Namely the operational magnitudes can be determined by the product of a conversion coefficient by exposure air kerma or fluence, etc. In particular in Mexico for the first time is determined the conversion coefficient (Cc) for operational magnitude Environmental Dose Equivalent H(10) by thermoluminescence dosimetry (TLD) technique. First 30 TLD-100 dosimeters are calibrated in terms of air kerma, then these dosimeters are irradiated inside a sphere ICRU type of PMMA and with the aid of theory cavity the absorbed dose in PMMA is determined at a depth of 10 mm within the sphere D{sub PMMA}(10), subsequently absorbed dose to ICRU tissue is corrected and the dose equivalent H(10) is determined. The Cc is determined as the ratio of H(10)/K{sub a} obtaining a value of 1.20 Sv Gy{sup -1} with a u{sub c}= 3.66%, this being consistent with the published value in ISO-4037-3 of 1.20 Sv Gy{sup -1} with a u{sub c}= 2%. (Author)

  3. Internal radiation doses in 372 persons who were dispatched to Fukushima from April 2011 to March 2012

    Energy Technology Data Exchange (ETDEWEB)

    Morita, Naoko; Kudo, Takashi [Nagasaki University, Atomic Disease Research Institute, Nagasaki (Japan); Miura, Miwa; Matsuda, Naoki [Nagasaki University, Center for Frontier Life Sciences, Nagasaki (Japan); Usa, Toshiro [Nagasaki University Hospital, International Hibakusha Medical Center, Nagasaki (Japan)

    2013-07-01

    The internal doses of 372 persons who were dispatched to the Fukushima prefecture at any time from April 2011 to March 2012 were examined using a whole body counter within 2 months after they left Fukushima. {sup 131}I was only detected in April while {sup 134}Cs and {sup 137}Cs were found up to November 2011. The maximum committed effective dose and thyroid equivalent dose were 22.4 μSv and 0.4 mSv, respectively, which were observed in April 2011 by the scenario of acute inhalation. The internal radioactivity was found in persons staying in almost all of the interior and the coastal regions regardless of the distance from the Fukushima-Daiichi nuclear power plant. Although there was no statistical significance, the detection rate of {sup 134}Cs and {sup 137}Cs appeared higher in subjects dispatched for relatively long-terms. Comparison of internal doses evaluated by the whole body counter and by prediction from environmental radioactivity indicates that the intake of radioactivity in March, April and possibly May 2011, would be mainly attributable to the inhalation of airborne radioactive particles, whereas in June and later months ingestion of contaminated food would be the major route of radioactive intake. These results suggest that the risk for internal exposure existed for approximately six months after the radiological accident in almost the entire area of Fukushima, however, adverse health consequences by the radiation dose due to internal exposure seem to be negligible. Furthermore, the present risk for internal exposure is quite low in the normal living situation. (author)

  4. Internal radiation doses in 372 persons who were dispatched to Fukushima from April 2011 to March 2012

    International Nuclear Information System (INIS)

    Morita, Naoko; Kudo, Takashi; Miura, Miwa; Matsuda, Naoki; Usa, Toshiro

    2013-01-01

    The internal doses of 372 persons who were dispatched to the Fukushima prefecture at any time from April 2011 to March 2012 were examined using a whole body counter within 2 months after they left Fukushima. 131 I was only detected in April while 134 Cs and 137 Cs were found up to November 2011. The maximum committed effective dose and thyroid equivalent dose were 22.4 μSv and 0.4 mSv, respectively, which were observed in April 2011 by the scenario of acute inhalation. The internal radioactivity was found in persons staying in almost all of the interior and the coastal regions regardless of the distance from the Fukushima-Daiichi nuclear power plant. Although there was no statistical significance, the detection rate of 134 Cs and 137 Cs appeared higher in subjects dispatched for relatively long-terms. Comparison of internal doses evaluated by the whole body counter and by prediction from environmental radioactivity indicates that the intake of radioactivity in March, April and possibly May 2011, would be mainly attributable to the inhalation of airborne radioactive particles, whereas in June and later months ingestion of contaminated food would be the major route of radioactive intake. These results suggest that the risk for internal exposure existed for approximately six months after the radiological accident in almost the entire area of Fukushima, however, adverse health consequences by the radiation dose due to internal exposure seem to be negligible. Furthermore, the present risk for internal exposure is quite low in the normal living situation. (author)

  5. Evaluation of the fetal dose during prophylactic placement of internal iliac artery balloon occlusion catheters in placenta accreta

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dong Sik [Dept. of Radiology, Gachon University Gil hospital, Incheon (Korea, Republic of); Ahn, Sung Min [Dept. of Radiological Science, Gachon University, Incheon (Korea, Republic of)

    2016-09-15

    Placenta accrete patients whose mother mortality rates are rather high due to massive bleeding during childbirth need to have Prophylactic placement of Internal Iliac Artery Balloon Occlusion Catheters procedure to reduce amount of blood loss and inoperative transfusion. Nevertheless, studies for mothers inevitably exposed to dose during PIIABOCs procedure have not been published many yet. Therefore, this study is to investigate exact information on radiation dose exposed to fetus during PIIABOCs procedure. Average effective dose of fetus per organ is 2.38∼8.83 mGy, measured highest at beam center and followed by eyeball, stomach and bladder. The result showed that the longer fluoroscopy time is used, the closer beam center is and the thicker abdominal thickness is, the more effective dose on fetus is increasing. When using the collimator and protection shown to decrease the effective dose and when using higher the patient table shown to decrease the effective dose. It has been reported that the threshold of deterministic effect is about 100mGy. Deterministic effect was regarded as a factor that would influence on fetus exposed by medical radiation than stochastic effect. Consequently, it concluded that dose exposed on fetus in PIIABOCs procedure was approximately 10% of threshold of deterministic effect with effective dose of 0.49∼18.27 mGy.

  6. Digitoxin medication and cancer; case control and internal dose-response studies

    International Nuclear Information System (INIS)

    Haux, Johan; Klepp, Olbjørn; Spigset, Olav; Tretli, Steinar

    2001-01-01

    Digitoxin induces apoptosis in different human malignant cell lines in vitro. In this paper we investigated if patients taking digitoxin for cardiac disease have a different cancer incidence compared to the general population. Computer stored data on digitoxin concentrations in plasma from 9271 patients with cardiac disease were used to define a user population. Age and sex matched controls from the Norwegian Cancer Registry were used to calculate the number of expected cancer cases. The population on digitoxin showed a higher incidence of cancer compared to the control population. However, an additional analysis showed that the population on digitoxin had a general increased risk of cancer already, before the start on digitoxin. Leukemia/lymphoma were the cancer types which stood out with the highest risk in the digitoxin population before starting on digitoxin. This indicates that yet unknown risk factors exist for cardiovascular disease and lymphoproliferative cancer. An internal dose-response analysis revealed a relationship between high plasma concentration of digitoxin and a lower risk for leukemia/lymphoma and for cancer of the kidney/urinary tract. Morbidity and mortality are high in the population on digitoxin, due to high age and cardiac disease.These factors disturb efforts to isolate an eventual anticancer effect of digitoxin in this setting. Still, the results may indicate an anticancer effect of digitoxin for leukemia/lymphoma and kidney/urinary tract cancers. Prospective clinical cancer trials have to be done to find out if digitoxin and other cardiac glycosides are useful as anticancer agents

  7. Outcomes of Direct Vision Internal Urethrotomy for Bulbar Urethral Strictures: Technique Modification with High Dose Triamcinolone Injection

    Directory of Open Access Journals (Sweden)

    Rishi Modh

    2015-01-01

    Full Text Available Objective. To evaluate the recurrence rate of bulbar urethral strictures managed with cold knife direct vision internal urethrotomy and high dose corticosteroid injection. Methods. 28 patients with bulbar urethral strictures underwent direct vision internal urethrotomy with high dose triamcinolone injection into the periurethral tissue and were followed up for recurrence. Results. Our cohort had a mean age of 60 years and average stricture length of 1.85 cm, and 71% underwent multiple previous urethral stricture procedures with an average of 5.7 procedures each. Our technique modification of high dose corticosteroid injection had a recurrence rate of 29% at a mean follow-up of 20 months with a low rate of urinary tract infections. In patients who failed treatment, mean time to stricture recurrence was 7 months. Patients who were successfully treated had significantly better International Prostate Symptom Scores at 6, 9, and 12 months. There was no significant difference in maximum flow velocity on Uroflowmetry at last follow-up but there was significant difference in length of follow-up (p=0.02. Conclusions. High dose corticosteroid injection at the time of direct vision internal urethrotomy is a safe and effective procedure to delay anatomical and symptomatic recurrence of bulbar urethral strictures, particularly in those who are poor candidates for urethroplasty.

  8. Outcomes of Direct Vision Internal Urethrotomy for Bulbar Urethral Strictures: Technique Modification with High Dose Triamcinolone Injection.

    Science.gov (United States)

    Modh, Rishi; Cai, Peter Y; Sheffield, Alyssa; Yeung, Lawrence L

    2015-01-01

    Objective. To evaluate the recurrence rate of bulbar urethral strictures managed with cold knife direct vision internal urethrotomy and high dose corticosteroid injection. Methods. 28 patients with bulbar urethral strictures underwent direct vision internal urethrotomy with high dose triamcinolone injection into the periurethral tissue and were followed up for recurrence. Results. Our cohort had a mean age of 60 years and average stricture length of 1.85 cm, and 71% underwent multiple previous urethral stricture procedures with an average of 5.7 procedures each. Our technique modification of high dose corticosteroid injection had a recurrence rate of 29% at a mean follow-up of 20 months with a low rate of urinary tract infections. In patients who failed treatment, mean time to stricture recurrence was 7 months. Patients who were successfully treated had significantly better International Prostate Symptom Scores at 6, 9, and 12 months. There was no significant difference in maximum flow velocity on Uroflowmetry at last follow-up but there was significant difference in length of follow-up (p = 0.02). Conclusions. High dose corticosteroid injection at the time of direct vision internal urethrotomy is a safe and effective procedure to delay anatomical and symptomatic recurrence of bulbar urethral strictures, particularly in those who are poor candidates for urethroplasty.

  9. Development and use of a fifteen year-old equivalent mathematical phantom for internal dose calculations. [Radiation dose distributions from /sup 99m/Tc-labeled compounds

    Energy Technology Data Exchange (ETDEWEB)

    Jones, R.M.; Poston, J.W.; Hwang, J.L.; Jones, T.D.; Warner, G.G.

    1976-06-01

    The existence of a phantom based on anatomical data for the average fifteen-year-old provides for a proficient means of obtaining estimates of absorbed dose for children of that age. Dimensions representative of an average fifteen-year-old human, obtained from various biological and medical research, were transformed into a mathematical construct of idealized shapes of the exterior, skeletal system, and internal organs of a human. The idealization for an average adult presently in use by the International Commission on Radiological Protection was used as a basis for design. The mathematical equations describing the phantom were developed to be readily adaptable to present-day methods of dose estimation. Typical exposure situations in nuclear medicine have previously been modeled for existing phantoms. With no further development of the exposure model necessary, adaptation to the fifteen-year-old phantom demonstrated the utility of the design. Estimates of absorbed dose were obtained for the administration of two radiopharmaceuticals, /sup 99m/Tc-sulfur colloid and /sup 99m/Tc-DMSA. (auth)

  10. The significance of neuroendocrine system state in estimation of nonstochastic effects of small doses of internal irradiation. (An experimental study)

    International Nuclear Information System (INIS)

    Dedov, V.I.; Norets, T.A.; Stepanenko, V.F.; Dedenkov, A.N.

    1987-01-01

    Data on long-term complex investigations of nonstochastic effects of low doses of internal irradiation on the level of a whole organism are presented. Experiments have been carried out with mongrel rats of both sexes and different ages up to the moment of introduction of radioactive compounds. Action of relatively and uniformly distributing in the organism radiactive compounds of selenium - 75 and sulfur - 35, which were introduced once intravenously in quantities forming absorbed doses in average on the whole body and ovaries (0.5 Gy), on endocrine glands and critical organs (up to 1.0 Gy) has been used as models of internal radiation. Data, testifying to the fact that the neuroendocrinal system, despite the existing opinion, is sensitive to action of low doses of internal irradiation compared with the recommended one as an ultimate permissible one for nonstochastic effects ( 0.5 Sv), that permits to suggest for using factors of the functional state of the neuroendocrine system as an informative and sensitive criterium of estimation of biological action of low doses of internal radiation, have been obtained. These factors along with doses on critical organs permit to estimate the degree of dangerous action of different radionuclides on the organism level. Dynamic studying of activity factors of the neuroendocrine system with simultaneous analysis of the state of harmonically dependent processes permits to estimate functional possibilities of irradiated organism, its viability, especially under conditions requiring increased stress, as well as to take into account such factors modifying a biological effect as age, animal sex, the character of absorbed dose distribution

  11. Determination of intake and internal radiation dose for occupationally exposed workers to iodine 131

    International Nuclear Information System (INIS)

    Kharita, M. H.; Maghrabi, M.; Sadyya, A.

    2004-12-01

    Workers who prepare and inject radioactive Iodine I 131 doses at the medical centers in Syria are potentially exposed to the radioactive intake by ingestion or inhalation during preparation or injection processes. The received amount of the radioactive intake differs according to the amount of the I 131 that released during the preparation or injection processes, and to the work conditions and the applying ways of the radiation protection principles. Because of this radioactive intake, the thyroid gland may expose to amounts of I 131 which may negatively affect the health of the workers, so it is necessary to make routine monitoring for all workers who receive an intake of more than 10% of the annual intake limit which is (2*10 6 Bq/y) for I 131 . To make this monitoring process, it is necessary to use either the thyroid gland counter in order to know the concentrated amount of the radioactivity in the gland, or the analysis of a 24 hours urine sample of the exposed workers to determine the eliminated amount of the radioactivity using gamma spectrometry, also the two processes can be applied at the same time. Since the thyroid gland counter is not available, the analysis of urine sample was done to determine the concentrated amount of the radioactivity in urine, then to estimate the radioactive intake and the internal radioactive dose. The results of applying this method dictated that some workers work in safe conditions according to the radiation protection and there is no need for them to make routine monitoring . But the other workers receive a radioactive intake of about 10% yearly of the annual intake limit and that requires a routine periodical monitoring for those workers in addition to the necessity of applying the principles of the radiation protection during the work with I 131 . These principles and systems should indicate the basic requirement of radiation protection that must be available in the laboratory that deal with I 131 either for therapy or for

  12. internal radiation dose assessment due to ionizing radio contaminants in some local foodstuffs

    International Nuclear Information System (INIS)

    AbdElKader, F.M.

    1996-01-01

    Over the last 30 years, radioactivity has been monitored in foodstuffs in Egypt. The present work deals with the radioactivity monitored during two years (1990 - 1992) at eight major Egyptian governorates. Sampled food items were selected to cover most foodstuffs eaten by egyptian population according to their habits. The daily food consumption by egyptian population and the constituents of such consumption were estimated according to published international data and knowledge of the different feeding habits of the egyptians. About 1200 samples were collected from the markets of the main city of each governorate and prepared for counting according to the egyptian kitchen habits. The counting systems used in determination and indentification of radionuclides were : a 3 inch HPGe detector attached to 800 channel MCA and PC and a 3 inch phoswich detector attached to an anticoincidence circuit for low beta / gamma counting. The gamma spectroscopy system was calibrated using isotopic solution mixture while the low beta counting system was calibrated using H CI. Counting time for the first system was 20 - 72 hours and for the second system was half to one hour. The main radionuclides identified in foodstuffs were Cs - 137 and K - 40 . The radioactivity concentration of Cs - 137 was found to be in the range between 1.0 Bq / Kg for macaroni and 3.5 Bq / Kg for nile beans. The K - 40 concentration range between 19 Bq / Kg for macaroni to 363 Bq / Kg for nile beans. The population weighted values in case of Cs - 137 was found as 3.56 Bq /d and for K - 40 was 188 Bq /d. The resulted effective dose due to food intake was found be 16 . 4 U Sv /a for Cs-137 and 354 μSv / a for K -40 . This value for Cs - 137 is found in the exemption limit while that of K -40 is twice the published value. This may depend on the egyptian feeding habit which depends mainly on wheat (bread) and nile beans which are very rich in potassium.The resulted collective dose was found to be : 21323 person

  13. Effects of body habitus on internal radiation dose calculations using the 5-year-old anthropomorphic male models

    Science.gov (United States)

    Xie, Tianwu; Kuster, Niels; Zaidi, Habib

    2017-08-01

    Computational phantoms are commonly used in internal radiation dosimetry to assess the amount and distribution pattern of energy deposited in various parts of the human body from different internal radiation sources. Radiation dose assessments are commonly performed on predetermined reference computational phantoms while the argument for individualized patient-specific radiation dosimetry exists. This study aims to evaluate the influence of body habitus on internal dosimetry and to quantify the uncertainties in dose estimation correlated with the use of fixed reference models. The 5-year-old IT’IS male phantom was modified to match target anthropometric parameters, including body weight, body height and sitting height/stature ratio (SSR), determined from reference databases, thus enabling the creation of 125 5-year-old habitus-dependent male phantoms with 10th, 25th, 50th, 75th and 90th percentile body morphometries. We evaluated the absorbed fractions and the mean absorbed dose to the target region per unit cumulative activity in the source region (S-values) of F-18 in 46 source regions for the generated 125 anthropomorphic 5-year-old hybrid male phantoms using the Monte Carlo N-Particle eXtended general purpose Monte Carlo transport code and calculated the absorbed dose and effective dose of five 18F-labelled radiotracers for children of various habitus. For most organs, the S-value of F-18 presents stronger statistical correlations with body weight, standing height and sitting height than BMI and SSR. The self-absorbed fraction and self-absorbed S-values of F-18 and the absorbed dose and effective dose of 18F-labelled radiotracers present with the strongest statistical correlations with body weight. For 18F-Amino acids, 18F-Brain receptor substances, 18F-FDG, 18F-L-DOPA and 18F-FBPA, the mean absolute effective dose differences between phantoms of different habitus and fixed reference models are 11.4%, 11.3%, 10.8%, 13.3% and 11.4%, respectively. Total body

  14. The internal dosimetry code PLEIADES.

    Science.gov (United States)

    Fell, T P; Phipps, A W; Smith, T J

    2007-01-01

    The International Commission on Radiological Protection (ICRP) has published dose coefficients for the ingestion or inhalation of radionuclides in a series of reports covering intakes by workers and members of the public, including children and pregnant or lactating women. The calculation of these coefficients divides naturally into two distinct parts-the biokinetic and dosimetric. This paper describes in detail the methods used to solve the biokinetic problem in the generation of dose coefficients on behalf of the ICRP, as implemented in the Health Protection Agency's internal dosimetry code PLEIADES. A summary of the dosimetric treatment is included.

  15. The internal dosimetry code PLEIADES

    International Nuclear Information System (INIS)

    Fell, T. P.; Phipps, A. W.; Smith, T. J.

    2007-01-01

    The International Commission on Radiological Protection (ICRP) has published dose coefficients for the ingestion or inhalation of radionuclides in a series of reports covering intakes by workers and members of the public, including children and pregnant or lactating women. The calculation of these coefficients divides naturally into two distinct parts - the biokinetic and dosimetric. This paper describes in detail the methods used to solve the biokinetic problem in the generation of dose coefficients on behalf of the ICRP, as implemented in the Health Protection Agency's internal dosimetry code PLEIADES. A summary of the dosimetric treatment is included. (authors)

  16. Effect of physiological factors on dose due to organically bound tritium

    International Nuclear Information System (INIS)

    Trivedi, A.

    1998-01-01

    The International Commission on Radiological Protection (ICRP) recommends the understanding of the effect of age, anatomical and physiological data on the doses in order to prescribe dose coefficient for radionuclides. The published data on OBT dose fraction after acute or chronic intakes of HTO are evaluated to examine the variation of OBT dose with the age and physiology of occupational workers. (author)

  17. Digitoxin medication and cancer; case control and internal dose-response studies

    Directory of Open Access Journals (Sweden)

    Spigset Olav

    2001-08-01

    Full Text Available Abstract Background Digitoxin induces apoptosis in different human malignant cell lines in vitro. In this paper we investigated if patients taking digitoxin for cardiac disease have a different cancer incidence compared to the general population. Methods Computer stored data on digitoxin concentrations in plasma from 9271 patients with cardiac disease were used to define a user population. Age and sex matched controls from the Norwegian Cancer Registry were used to calculate the number of expected cancer cases. Results The population on digitoxin showed a higher incidence of cancer compared to the control population. However, an additional analysis showed that the population on digitoxin had a general increased risk of cancer already, before the start on digitoxin. Leukemia/lymphoma were the cancer types which stood out with the highest risk in the digitoxin population before starting on digitoxin. This indicates that yet unknown risk factors exist for cardiovascular disease and lymphoproliferative cancer. An internal dose-response analysis revealed a relationship between high plasma concentration of digitoxin and a lower risk for leukemia/lymphoma and for cancer of the kidney/urinary tract. Conclusion Morbidity and mortality are high in the population on digitoxin, due to high age and cardiac disease.These factors disturb efforts to isolate an eventual anticancer effect of digitoxin in this setting. Still, the results may indicate an anticancer effect of digitoxin for leukemia/lymphoma and kidney/urinary tract cancers. Prospective clinical cancer trials have to be done to find out if digitoxin and other cardiac glycosides are useful as anticancer agents.

  18. Second International MELODI Workshop on Low Dose Risk Research - Slides of the presentations

    International Nuclear Information System (INIS)

    Repussard, J.; Weiss, W.; Quintana Trias, O.; Rosario Perez, M. del; Andersen, M.; Rudiger Trott, K.; Ottolenghi, A.; Smyth, V.; Graw, J.; Little, M.P.; Yonai, S.; Barcellos-Hoff, M.H.; Bouffler, S.; Chevillard, S.; Jeggo, P.; Sabatier, L.; Baatout, S.; Niwa, O.; Oesch, F.; Atkinson, M.; Averbeck, D.; Lloyd, D.; O'Neill, P.

    2011-01-01

    The MELODI (Multidisciplinary European Low Dose Initiative) mission is to impulse low dose risk research in Europe through a strategic research agenda (SRA) and road-map of priorities. The last presentation is dedicated to the SRA and its preference research programs. The other presentations deal principally with the low-dose exposure in medical uses of ionizing radiations, radiosensitivity, radiation-induced cataracts, or epidemiology and radiobiology of cardiovascular disease. This document is composed of the slides of the presentations

  19. Comparison of conversion coefficients for equivalent dose in terms of air kerma using a sitting and standing female adult voxel simulators exposure to photons in antero-posterior irradiation geometry

    International Nuclear Information System (INIS)

    Cavalcante, F.R.; Galeano, D.C.; Carvalho Júnior, A.B.; Hunt, J.

    2014-01-01

    Due to the difficulty in implementing invasive techniques for calculations of dose for some exposure scenarios, computational simulators have been created to represent as realistically as possible the structures of the human body and through radiation transport simulations to obtain conversion coefficients (CCs) to estimate dose. In most published papers simulators are implemented in the standing posture and this may not describe a real scenario of exposure. In this work we developed exposure scenarios in the Visual Monte Carlo (VMC) code using a female simulator in standing and sitting postures. The simulator was irradiated in the antero-posterior (AP) geometry by a plane source of monoenergetic photons with energy from 10 keV to 2 MeV. The conversion coefficients for equivalent dose in terms of air kerma (H T /K air ) were calculated for both scenarios and compared. The results show that the percentage difference of CCs for the organs of the head and thorax was not significant (less than 5%) since the anatomic position of the organs is the same in both postures. The percentage difference is more significant to the ovaries (71% for photon energy of 20 keV), to the bladder (39% at 60 keV) and to the uterus (37% at 100 keV) due to different processes of radiation interactions in the legs of the simulator when its posture is changed. For organs and tissues that are distributed throughout the entire body, such as bone (21% at 100 keV) and muscle (30% at 80 keV) the percentage difference of CCs reflects a reduction of interaction of photons with the legs of the simulator. Therefore, the calculation of conversion coefficients using simulators in the sitting posture is relevant for a more accurate dose estimation in real exposures to radiation. - Highlights: ► Scenarios of external photon exposures were performed in VMC code. ► The FAX simulator was irradiated in sitting and standing postures. ► The irradiation geometry used was the antero-posterior (AP). ► The

  20. Validation of a dose-point kernel convolution technique for internal dosimetry

    International Nuclear Information System (INIS)

    Giap, H.B.; Macey, D.J.; Bayouth, J.E.; Boyer, A.L.

    1995-01-01

    The objective of this study was to validate a dose-point kernel convolution technique that provides a three-dimensional (3D) distribution of absorbed dose from a 3D distribution of the radionuclide 131 I. A dose-point kernel for the penetrating radiations was calculated by a Monte Carlo simulation and cast in a 3D rectangular matrix. This matrix was convolved with the 3D activity map furnished by quantitative single-photon-emission computed tomography (SPECT) to provide a 3D distribution of absorbed dose. The convolution calculation was performed using a 3D fast Fourier transform (FFT) technique, which takes less than 40 s for a 128 x 128 x 16 matrix on an Intel 486 DX2 (66 MHz) personal computer. The calculated photon absorbed dose was compared with values measured by thermoluminescent dosimeters (TLDS) inserted along the diameter of a 22 cm diameter annular source of 131 I. The mean and standard deviation of the percentage difference between the measurements and the calculations were equal to -1% and 3.6% respectively. This convolution method was also used to calculate the 3D dose distribution in an Alderson abdominal phantom containing a liver, a spleen, and a spherical tumour volume loaded with various concentrations of 131 I. By averaging the dose calculated throughout the liver, spleen, and tumour the dose-point kernel approach was compared with values derived using the MIRD formalism, and found to agree to better than 15%. (author)

  1. International standard (ISO) of radiation sterilization and issues in the sterilization dose setting

    International Nuclear Information System (INIS)

    Takehisa, Masaaki

    1995-01-01

    The ISO dose setting method 1 uses bioburden and verification by sublethal sterility test. Current devices produced in clean environmental have low bioburden, however, sensitivity of verification test declines at low bioburden. Validation of verification in this region should be further studied. A dose setting using D 10 of bioburden isolates should be reevaluated and included in the ISO. (author)

  2. Coordinated research efforts for establishing an international radiotherapy dose intercomparison service based on the alanine/ESR system

    International Nuclear Information System (INIS)

    Nette, H.P.; Onori, S.; Fattibene, P.; Regulla, D.; Wieser, A.

    1993-01-01

    The IAEA has long been active in the field of high-dose standardization. An International Dose Assurance Service (IDAS) was established based on alanine/ESR dosimetry. This service operates over the range of 100 Gy to 100 kGy and is directed towards industrial radiation processing in IAEA member states. It complements the IAEA/WHO TLD postal dose intercomparison service for dose assurance in hospital radiotherapy departments. Experience with the alanine high dose service suggests that the alanine dosimeter might provide superior performance to TLD in the therapy dose range. Preliminary test measurements with the participation of GSF/Germany, Istituto Superiore di Sanita/Italy (both providing alanine dosimeters and their evaluation) and IAEA (providing reference irradiations) seems to justify research efforts through an IAEA Coordinated Research Programme (CRP). This CRP, entitled ''Therapy Level Dosimetry with the Alanine/ESR System'' is presently under set-up. It will include general work common to all assigned/potential contract holders as well as some specific research topics in accordance to individual proposals of each participant. (author)

  3. Effects of body habitus on internal radiation dose calculations using the 5-year-old anthropomorphic male models

    DEFF Research Database (Denmark)

    Xie, Tianwu; Kuster, Niels; Zaidi, Habib

    2017-01-01

    Xtended general purpose Monte Carlo transport code and calculated the absorbed dose and effective dose of five 18F-labelled radiotracers for children of various habitus. For most organs, the S-value of F-18 presents stronger statistical correlations with body weight, standing height and sitting height than BMI...... and SSR. The self-absorbed fraction and self-absorbed S-values of F-18 and the absorbed dose and effective dose of 18F-labelled radiotracers present with the strongest statistical correlations with body weight. For 18F-Amino acids, 18F-Brain receptor substances, 18F-FDG, 18F-L-DOPA and 18F-FBPA, the mean...... absolute effective dose differences between phantoms of different habitus and fixed reference models are 11.4%, 11.3%, 10.8%, 13.3% and 11.4%, respectively. Total body weight, standing height and sitting height have considerable effects on human internal dosimetry. Radiation dose calculations...

  4. A probabilistic approach to quantify the uncertainties in internal dose assessment using response surface and neural network

    International Nuclear Information System (INIS)

    Baek, M.; Lee, S.K.; Lee, U.C.; Kang, C.S.

    1996-01-01

    A probabilistic approach is formulated to assess the internal radiation exposure following the intake of radioisotopes. This probabilistic approach consists of 4 steps as follows: (1) screening, (2) quantification of uncertainties, (3) propagation of uncertainties, and (4) analysis of output. The approach has been applied for Pu-induced internal dose assessment and a multi-compartment dosimetric model is used for internal transport. In this approach, surrogate models of original system are constructed using response and neural network. And the results of these surrogate models are compared with those of original model. Each surrogate model well approximates the original model. The uncertainty and sensitivity analysis of the model parameters are evaluated in this process. Dominant contributors to each organ are identified and the results show that this approach could serve a good tool of assessing the internal radiation exposure

  5. The role of agricultural and natural ecosystems in the internal dose formation in the inhabitants of a controlled area

    International Nuclear Information System (INIS)

    Balonov, M.I.; Travnikova, I.G.

    1990-01-01

    The dynamics of caesium radionuclide transfer to agricultural and natural food products produced in western areas of the Bryansk region during 3 years after the Chernobyl accident and its change due to the protective measures adopted have been determined. It has been shown that the role of agricultural and natural (mushrooms, fish, berries) food products in the people's internal irradiation may be equally important both with routine diet and with the food restrictions imposed. The substitution of local food products for radiation-free ones reduced the internal irradiation dose in the adult rural inhabitants of the controlled area by 70-86% during 1.5 years. (author)

  6. Measurements of 222Rn and its daughters and estimation of internal doses to workers in underground buildings

    International Nuclear Information System (INIS)

    Cao Jianping; Lu Zhizhao; Li Yuanshan

    1993-03-01

    The results of concentration measuring of 222 Ru and its daughters and estimation of internal doses to workers in the underground buildings at Nanjing city are presented. The double filtering membrane method and Thomas method were used in the monitoring of 222 Rn and its daughters, and the dose conversion factor was taken from the latest UNSCEAR report. Concentration distributions of 222 Rn and its daughters were approximately log-normal. The geometric means for 222 Rn was 40.5 Bq · m -3 and for its daughters was 1.4 x 10 -7 J · m -3 . The equilibrium factor was 0.63. The radioactive equilibrium ratio between short-lived 222 Rn daughters was 1:0.57:0.49. The estimation value of annual effective dose equivalent from 222 Rn daughters to workers working at underground sites was 1.3 mSv, which was 86% higher than that of those working on ground sites

  7. Identification and analysis of main radionuclides that potentially contribute to the internal dose for workers at radiopharmacy facilities

    International Nuclear Information System (INIS)

    Sanches, Matias Puga

    2004-01-01

    The optimization principle in radiation protection means that there is a reasonable balance between resources used to monitor exposures and the benefits due to the monitoring program. Programs for the monitoring of workers handling radioactive materials are influenced by numerous factors. Estimation of internal doses due to inhalation or ingestion of radioactive materials is often based on measurements of the activity in the tissues of the body and in excreta, following a given intake. In order to enable dose estimations using the biokinetic models recommended by the ICRP and laboratory data, it is proposed to carry out comprehensive study to identify the main radionuclides that potentially contribute to the internal dose of workers at radiopharmacy facilities. The applied methodology for identification of these radionuclides takes into account criteria set out by the ICRP and IAEA. The practical purpose to set up this study was to establish a consistent approach to ensure that the dose assessments are as simple as possible and guarantee the necessary quality standards. The result of this study has indicated the requirement of routine measurements for seven radionuclides over all range of radioactive material compounds, handled at the radiopharmacy plant of IPEN, avoiding unjustifiable work concerning activity levels that are not relevant for the health of the occupationally exposed persons. The main intake pathways, the appropriate monitoring frequencies and derived reference level have also been identified. (author)

  8. Awareness and knowledge among internal medicine house-staff for dose adjustment of commonly used medications in patients with CKD.

    Science.gov (United States)

    Surana, Sikander; Kumar, Neeru; Vasudeva, Amita; Shaikh, Gulvahid; Jhaveri, Kenar D; Shah, Hitesh; Malieckal, Deepa; Fogel, Joshua; Sidhu, Gurwinder; Rubinstein, Sofia

    2017-01-17

    Drug dosing errors result in adverse patient outcomes and are more common in patients with chronic kidney disease (CKD). As internists treat the majority of patients with CKD, we study if Internal Medicine house-staff have awareness and knowledge about the correct dosage of commonly used medications for those with CKD. A cross-sectional survey was performed and included 341 participants. The outcomes were the awareness of whether a medication needs dose adjustment in patients with CKD and whether there was knowledge for the level of glomerular filtration rate (GFR) a medication needs to be adjusted. The overall pattern for all post-graduate year (PGY) groups in all medication classes was a lack of awareness and knowledge. For awareness, there were statistically significant increased mean differences for PGY2 and PGY3 as compared to PGY1 for allergy, endocrine, gastrointestinal, and rheumatologic medication classes but not for analgesic, cardiovascular, and neuropsychotropic medication classes. For knowledge, there were statistically significant increased mean differences for PGY2 and PGY3 as compared to PGY1 for allergy, cardiovascular, endocrine, and gastrointestinal, medication classes but not for analgesic, neuropsychotropic, and rheumatologic medication classes. Internal Medicine house-staff across all levels of training demonstrated poor awareness and knowledge for many medication classes in CKD patients. Internal Medicine house-staff should receive more nephrology exposure and formal didactic educational training during residency to better manage complex treatment regimens and prevent medication dosing errors.

  9. Absorbed dose calculations to blood and blood vessels for internally deposited radionuclides

    International Nuclear Information System (INIS)

    Akabani, G.; Poston, J.W. Sr.

    1992-01-01

    At present, absorbed dose calculations for radionuclides in the human circulatory system use relatively simple models and are restricted in their applications. To determine absorbed doses to the blood and to the surface of the blood vessel wall, Monte Carlo calculations were performed using the code Electron Gamma Shower (EGS4). Absorbed doses were calculated for the blood and the blood vessel wall (lumen) for different blood vessel sizes. The radionuclides chosen for this study were those commonly used in nuclear medicine. No diffusion of the radionuclide into the blood vessel was or cross fire between blood vessels was assumed. Results are useful in assessing the doses to blood and blood vessel walls for different nuclear medicine procedures

  10. Absorbed dose calculations to blood and blood vessels for internally deposited radionuclides

    International Nuclear Information System (INIS)

    Akabani, G.; Poston, J.W.

    1991-05-01

    At present, absorbed dose calculations for radionuclides in the human circulatory system used relatively simple models and are restricted in their applications. To determine absorbed doses to the blood and to the surface of the blood vessel wall, EGS4 Monte Carlo calculations were performed. Absorbed doses were calculated for the blood and the blood vessel wall (lumen) for different blood vessels sizes. The radionuclides chosen for this study were those commonly used in nuclear medicine. No diffusion of the radionuclide into the blood vessel was assumed nor cross fire between vessel was assumed. Results are useful in assessing the dose in blood and blood vessel walls for different nuclear medicine procedures. 6 refs., 6 figs., 5 tabs

  11. Methods for reducing internal collective doses due to contamination of agricultural lands

    International Nuclear Information System (INIS)

    Prister, B.S.; Novikova, N.K.; Tkachenko, N.V.; Nagovisyna, L.I.; Berezhnaya, T.I.; Semenyuk, N.D.; Rudoj, V.M.

    1990-01-01

    Radioactive contamination of agricultural lands in 30 km vicinity of Chernobyl NPP asw well as agricultural products involved in food chains is considered. Attention is paid to population collective doses due to intake of contaminated food. It is shown that target optimization of agricultural production structure in territories where food contamination does not result in increase of population dose limit lies in achievement of minimal inclusion of radionuclides in human diet

  12. Doses to internal organs for various breast radiation techniques - implications on the risk of secondary cancers and cardiomyopathy

    Directory of Open Access Journals (Sweden)

    Keller Brian M

    2011-01-01

    Full Text Available Abstract Background Breast cancers are more frequently diagnosed at an early stage and currently have improved long term outcomes. Late normal tissue complications induced by adjuvant radiotherapy like secondary cancers or cardiomyopathy must now be avoided at all cost. Several new breast radiotherapy techniques have been developed and this work aims at comparing the scatter doses of internal organs for those techniques. Methods A CT-scan of a typical early stage left breast cancer patient was used to describe a realistic anthropomorphic phantom in the MCNP Monte Carlo code. Dose tally detectors were placed in breasts, the heart, the ipsilateral lung, and the spleen. Five irradiation techniques were simulated: whole breast radiotherapy 50 Gy in 25 fractions using physical wedge or breast IMRT, 3D-CRT partial breast radiotherapy 38.5 Gy in 10 fractions, HDR brachytherapy delivering 34 Gy in 10 treatments, or Permanent Breast 103Pd Seed Implant delivering 90 Gy. Results For external beam radiotherapy the wedge compensation technique yielded the largest doses to internal organs like the spleen or the heart, respectively 2,300 mSv and 2.7 Gy. Smaller scatter dose are induced using breast IMRT, respectively 810 mSv and 1.1 Gy, or 3D-CRT partial breast irradiation, respectively 130 mSv and 0.7 Gy. Dose to the lung is also smaller for IMRT and 3D-CRT compared to the wedge technique. For multicatheter HDR brachytherapy a large dose is delivered to the heart, 3.6 Gy, the spleen receives 1,171 mSv and the lung receives 2,471 mSv. These values are 44% higher in case of a balloon catheter. In contrast, breast seeds implant is associated with low dose to most internal organs. Conclusions The present data support the use of breast IMRT or virtual wedge technique instead of physical wedges for whole breast radiotherapy. Regarding partial breast irradiation techniques, low energy source brachytherapy and external beam 3D-CRT appear safer than 192Ir HDR

  13. DoReMi workshop on multidisciplinary approaches to evaluating cancer risks associated with low-dose internal contamination

    International Nuclear Information System (INIS)

    Laurier, D.; Guseva Canu, I.; Bertho, J.M.; Blanchardon, E.; Rage, E.; Baatout, S.; Bouffler, S.; Cardis, E.; Gomolka, M.; Kreuzer, M.; Hall, J.; Kesminiene, A.

    2012-01-01

    A workshop dedicated to cancer risks associated with low-dose internal contamination was organised in March 2011, in Paris, in the framework of the DoReMi (Low Dose Research towards Multidisciplinary Integration) European Network of Excellence. The aim was to identify the best epidemiological studies that provide an opportunity to develop a multidisciplinary approach to improve the evaluation of the cancer risk associated with internal contamination. This workshop provided an opportunity for in-depth discussions between researchers working in different fields including (but not limited to) epidemiology, dosimetry, biology and toxicology. Discussions confirmed the importance of research on the health effects of internal contamination. Several existing epidemiological studies provide a real possibility to improve the quantification of cancer risk associated with internal emitters. Areas for future multidisciplinary collaborations were identified, that should allow feasibility studies to be carried out in the near future. The goal of this paper is to present an overview of the presentations and discussions that took place during this workshop. (authors)

  14. Time- and dose rate-related effects of internal 177Lu exposure on gene expression in mouse kidney tissue

    International Nuclear Information System (INIS)

    Schüler, Emil; Rudqvist, Nils; Parris, Toshima Z.; Langen, Britta; Spetz, Johan; Helou, Khalil; Forssell-Aronsson, Eva

    2014-01-01

    Introduction: The kidneys are the dose-limiting organs in some radionuclide therapy regimens. However, the biological impact of internal exposure from radionuclides is still not fully understood. The aim of this study was to examine the effects of dose rate and time after i.v. injection of 177 LuCl 3 on changes in transcriptional patterns in mouse kidney tissue. Methods: To investigate the effect of dose rate, female Balb/c nude mice were i.v. injected with 11, 5.6, 1.6, 0.8, 0.30, and 0 MBq of 177 LuCl 3 , and killed at 3, 6, 24, 48, 168, and 24 hours after injection, respectively. Furthermore, the effect of time after onset of exposure was analysed using mice injected with 0.26, 2.4, and 8.2 MBq of 177 LuCl 3 , and killed at 45, 90, and 140 days after injection. Global transcription patterns of irradiated kidney cortex and medulla were assessed and enriched biological processes were determined from the regulated gene sets using Gene Ontology terms. Results: The average dose rates investigated were 1.6, 0.84, 0.23, 0.11 and 0.028 mGy/min, with an absorbed dose of 0.3 Gy. At 45, 90 and 140 days, the absorbed doses were estimated to 0.3, 3, and 10 Gy. In general, the number of differentially regulated transcripts increased with time after injection, and decreased with absorbed dose for both kidney cortex and medulla. Differentially regulated transcripts were predominantly involved in metabolic and stress response-related processes dependent on dose rate, as well as transcripts associated with metabolic and cellular integrity at later time points. Conclusion: The observed transcriptional response in kidney tissue was diverse due to difference in absorbed dose, dose rate and time after exposure. Nevertheless, several transcripts were significantly regulated in all groups despite differences in exposure parameters, which may indicate potential biomarkers for exposure of kidney tissue

  15. Comparison of conversion coefficients for equivalent dose in terms of air kerma for photons using a male adult voxel simulator in sitting and standing posture with geometry of irradiation antero-posterior

    International Nuclear Information System (INIS)

    Galeano, D.C.; Cavalcante, F.R.; Carvalho, A.B.; Hunt, J.

    2014-01-01

    The dose conversion coefficient (DCC) is important to quantify and assess effective doses associated with medical, professional and public exposures. The calculation of DCCs using anthropomorphic simulators and radiation transport codes is justified since in-vivo measurement of effective dose is extremely difficult and not practical for occupational dosimetry. DCCs have been published by the ICRP using simulators in a standing posture, which is not always applicable to all exposure scenarios, providing an inaccurate dose estimation. The aim of this work was to calculate DCCs for equivalent dose in terms of air kerma (H/Kair) using the Visual Monte Carlo (VMC) code and the VOXTISS8 adult male voxel simulator in sitting and standing postures. In both postures, the simulator was irradiated by a plane source of monoenergetic photons in antero-posterior (AP) geometry. The photon energy ranged from 15 keV to 2 MeV. The DCCs for both postures were compared and the DCCs for the standing simulator were higher. For certain organs, the difference of DCCs were more significant, as in gonads (48% higher), bladder (16% higher) and colon (11% higher). As these organs are positioned in the abdominal region, the posture of the anthropomorphic simulator modifies the form in which the radiation is transported and how the energy is deposited. It was also noted that the average percentage difference of conversion coefficients was 33% for the bone marrow, 11% for the skin, 13% for the bone surface and 31% for the muscle. For other organs, the percentage difference of the DCCs for both postures was not relevant (less than 5%) due to no anatomical changes in the organs of the head, chest and upper abdomen. We can conclude that is important to obtain DCCs using different postures from those present in the scientific literature. - Highlights: • Scenarios of external photon exposures were performed in VMC code. • The VOXTISS8 simulator was irradiated in standing and sitting postures.

  16. Pilot website to support international collaboration for dose assessments in a radiation emergency

    Energy Technology Data Exchange (ETDEWEB)

    Livingston, G.K., E-mail: Gordon.Livingston@orise.orau.gov [Oak Ridge Associated Universities, REAC/TS, Radiation Emergency Medicine (REM), P.O. Box 117, Oak Ridge, TN 37831 (United States); Wilkins, R.C., E-mail: Ruth.Wilkins@hc-sc.gc.ca [Health Canada, Consumer and Clinical Radiation Protection Bureau, Ottawa, ON K1A 1C1 (Canada); Ainsbury, E.A., E-mail: liz.ainsbury@hpa.org.uk [Health Protection Agency, Radiation Protection Division, Chilton, Didcot, Oxfordshire OX11 0RQ (United Kingdom)

    2011-09-15

    Nuclear terrorism has emerged as a significant threat which could require timely medical interventions to reduce potential radiation casualties. Early dose assessments are critical since optimal care depends on knowing a victim's radiation dose. The dicentric chromosome aberration assay is considered the 'gold standard' to estimate the radiation dose because the yield of dicentrics correlates positively with the absorbed dose. Dicentrics have a low background frequency, are independent of age and gender and are relatively easy to identify. This diagnostic test for radiation exposure, however, is labor intensive and any single or small group of laboratories could easily be overwhelmed by a mass casualty event. One solution to this potential problem is to link the global WHO BioDoseNet members via the Internet so multiple laboratories could work cooperatively to screen specimens for dicentric chromosomes and generate timely dose estimates. Inter-laboratory comparison studies have shown that analysis of electronic chromosome images viewed on the computer monitor produces scoring accuracy equivalent to viewing live images in the microscope. This functional equivalence was demonstrated during a comparative study involving five laboratories constructing {sup 60}Co gamma ray calibration curves and was further confirmed when comparing results of blind dose estimates submitted by each laboratory. It has been further validated in two recent WHO BioDoseNet trial exercises where 20 metaphase images were shared by e-mail and 50 images were shared on a test website created for this purpose. The Internet-based exercise demonstrated a high level of concordance among 20 expert scorers who evaluated the same 50 metaphase spreads selected to exhibit no, low, moderate and severe radiation damage. Nineteen of 20 scorers produced dicentric equivalent counts within the 95% confidence limits of the mean. The Chi-squared test showed strong evidence of homogeneity in the data

  17. Pilot website to support international collaboration for dose assessments in a radiation emergency

    International Nuclear Information System (INIS)

    Livingston, G.K.; Wilkins, R.C.; Ainsbury, E.A.

    2011-01-01

    Nuclear terrorism has emerged as a significant threat which could require timely medical interventions to reduce potential radiation casualties. Early dose assessments are critical since optimal care depends on knowing a victim's radiation dose. The dicentric chromosome aberration assay is considered the 'gold standard' to estimate the radiation dose because the yield of dicentrics correlates positively with the absorbed dose. Dicentrics have a low background frequency, are independent of age and gender and are relatively easy to identify. This diagnostic test for radiation exposure, however, is labor intensive and any single or small group of laboratories could easily be overwhelmed by a mass casualty event. One solution to this potential problem is to link the global WHO BioDoseNet members via the Internet so multiple laboratories could work cooperatively to screen specimens for dicentric chromosomes and generate timely dose estimates. Inter-laboratory comparison studies have shown that analysis of electronic chromosome images viewed on the computer monitor produces scoring accuracy equivalent to viewing live images in the microscope. This functional equivalence was demonstrated during a comparative study involving five laboratories constructing 60 Co gamma ray calibration curves and was further confirmed when comparing results of blind dose estimates submitted by each laboratory. It has been further validated in two recent WHO BioDoseNet trial exercises where 20 metaphase images were shared by e-mail and 50 images were shared on a test website created for this purpose. The Internet-based exercise demonstrated a high level of concordance among 20 expert scorers who evaluated the same 50 metaphase spreads selected to exhibit no, low, moderate and severe radiation damage. Nineteen of 20 scorers produced dicentric equivalent counts within the 95% confidence limits of the mean. The Chi-squared test showed strong evidence of homogeneity in the data (p = 0

  18. Use of thermoluminescence dosimetry for evaluation of internal beta dose-rate in archaeological dating

    Energy Technology Data Exchange (ETDEWEB)

    Bailiff, I K; Aitken, M J [Oxford Univ. (UK). Research Lab. for Archaeology

    1980-07-01

    An experimental technique is described for the absolute determination of beta dose-rate in pottery. The calibrated system utilizes thermoluminescent dosimeters (natural calcium fluoride) which are located external to the pottery sample. These measurements give an evaluation of the dose-rate at the centre of the pottery that is effectively independent of the relative importance of the thorium, uranium and potassium content (typically 12 ppm Th, 3 ppm U and 1% K/sub 2/O in pottery). This has been checked using analysed uranium, thorium and potassium materials. A dose-rate evaluation may be made after 10-14 d with an accuracy of +-5%, where the dose-rate to the dosimeter is of the order of 0.3 mrad d/sup -1/. Although the background dose-rate due to cosmic radiation and that arising from radioactive impurities in the calcium fluoride is significant (one third), measurements have shown that it may be accurately established. The technique described is to be preferred to other systems used in pottery dating because of its independence of relative radioisotope concentration.

  19. Technical basis for using nose swab bioassay data for early internal dose assessment

    International Nuclear Information System (INIS)

    Guilmette, Raymond A.; Bertelli, Luiz; Miller, Guthrie; Little, Tom T.

    2007-01-01

    One of the challenges to the dose assessment team in response to an inhalation incident in the workplace is to provide the occupational physicians, operational radiation protection personnel and line managers with early estimates of radionuclide intakes so that appropriate consequence management and mitigation can be done. For radionuclides such as Pu, where in vivo counting is not adequately sensitive, other techniques such as the measurement of removable radionuclide from the nasal airway passages can be used. At Los Alamos National Laboratory (LANL), nose swabs of the ET 1 region have been used routinely as a first response to airborne Pu releases in the workplace, as well as for other radionuclides. This paper presents the results of analysing over 15 years of nose swab data, comparing these with dose assessments performed using the Bayesian methods developed at LANL. The results provide empirical support for using nose swab data for early dose assessments. For Pu, a rule of thumb is a dose factor of 0.8 mSv Bq -1 , assuming a linear relationship between nasal swab activity and committed effective dose equivalent. However, this value is specific to the methods and models used at LANL, and should not be applied directly without considering possible differences in measurement and calculation methods. (authors)

  20. Level of radon and its daughters, and internal exposure doses in Shaanxi province

    International Nuclear Information System (INIS)

    Fan Xin; Zhang Yawei; Yu Huilian

    1992-01-01

    About 4500 indoor and outdoor air samples were collected with FDT-84 sampler throughout Shaanxi Province in various seasons, and the concentrations of radon and its daughters in the air were determined with FD-3016 scintillator. Meanwhile, the diurnal, seasonal and altitudinal variation of radon and its progeny in Xi'an area were observed. The annual effective dose equivalent for individual adult resident was estimated to be 1.73 mSv·a -1 and the annual collective effective dose equivalent for the residents- in the whole province was estimated to be 5.09 ± 10 4 man.Sv·a -1 . The concentration levels and the doses are within the range of the data published in UNSCEAR reports in recent years, and all of them are in the normal range of the natural background

  1. Development of a Method to Assess the Radiation Dose due to Internal Exposure to Short-lived Radioactive Materials

    International Nuclear Information System (INIS)

    Benmaman, D.; Koch, J.; Ribak, J.

    2014-01-01

    Work with radioactive materials requires monitoring of the employees' exposure to ionizing radiation. Employees may be exposed to radiation from internal and/or external exposure. Control of external exposure is mostly conducted through personal radiation dosimeters provided to employees. Control of internal exposure can be performed by measuring the concentration of radioactive substances excreted in urine or through whole-body counting in which the entire body or target organs are scanned with a sensitive detector system (1). According to the regulations in Israel an employee that may be internally exposed must undergo an exposure control at least once every three months. The idea lying behind the control of internal exposure by urine testing is that if radioactive material has penetrated into the employee body, it can be detected even if the test is performed once every three months. A model was fitted for each element describing its dispersion in the body and its excretion therefrom (2). By means of this model, one can estimate the activity that entered the body and calculate the resulting radiation dose to which the worker was exposed. There is a problem to implement this method when it comes to short-lived radioactive materials, for which it is very likely that the material that penetrated into the body has decayed and cannot be detected by testing once every three months. As a result, workers with short-lived radioactive materials are presently not monitored for internal exposure, in contradiction to the requirements of the Safety at Work Regulations. The purpose of the study is to develop an alternative method to assess the amount of radioactive material absorbed in the body and the resulting radiation dose due to internal exposure of workers to short-lived radioactive materials

  2. Thyroid dose of I-131 absorbed by the internal organs of a pregnant woman

    International Nuclear Information System (INIS)

    Arcos P, A.; Manzanares A, E.; Vega C, H.R.; Leon, C.L. de

    2007-01-01

    The use of nuclear techniques, for diagnosis or treatment, generates stress in the patient and its relatives. During the pregnancy some sufferings related with the thyroid gland can be presented. If the patient is pregnant, OEP or NOEP, the stress comes from the fear to that the product can it turns affected. The dose is calculated that the Iodine 131, captured by the thyroid of a woman with three months of pregnancy, it deposits in the brain, stomach, heart, kidneys, liver, lungs, ovaries, pancreas, thymus, spleen and in the uterus. The thymus is the organ that receives the biggest dose. (Author)

  3. Evaluation of the absorbed doses in conditions of external and internal contamination with radionuclides

    International Nuclear Information System (INIS)

    Milivojevic, K.; Stojanovic, D.; Markovic, P.

    1981-01-01

    In experimental conditions of contamination with radionuclides of the skin and skin injuries, an evaluation of the degree of local irradiation in decontamined region and doses absorbed in organs of selective accumulating was carried out by use of mathematical models and tissue-equivalent thermoluminescent dosemeters. The evaluation of the absorbed doses based on conception, that in adequate analyses of decontamination effect, as a most efficient medico-prophilactic measure from local and total irradiation, should be taken into account the total body burden of the penetrated radionuclide, selective accumulating in critical organs or tissues, as well as the residual radioactivity in decontaminated region. (author)

  4. Doses from radiation exposure

    CERN Document Server

    Menzel, H G

    2012-01-01

    Practical implementation of the International Commission on Radiological Protection's (ICRP) system of protection requires the availability of appropriate methods and data. The work of Committee 2 is concerned with the development of reference data and methods for the assessment of internal and external radiation exposure of workers and members of the public. This involves the development of reference biokinetic and dosimetric models, reference anatomical models of the human body, and reference anatomical and physiological data. Following ICRP's 2007 Recommendations, Committee 2 has focused on the provision of new reference dose coefficients for external and internal exposure. As well as specifying changes to the radiation and tissue weighting factors used in the calculation of protection quantities, the 2007 Recommendations introduced the use of reference anatomical phantoms based on medical imaging data, requiring explicit sex averaging of male and female organ-equivalent doses in the calculation of effecti...

  5. Lake fish as the main contributor of internal dose to lakeshore residents in the Chernobyl contaminated area

    International Nuclear Information System (INIS)

    Travnikova, I.G.; Bazjukin, A.N.; Bruk, G.Ja.; Shutov, V.N.; Balonov, M.I.; Skuterud, L.; Mehli, H.; Strand, P.

    2004-01-01

    Two field expeditions in 1996 studied 137 Cs intake patterns and its content in the bodies of adult residents from the village Kozhany in the Bryansk region, Russia, located on the shore of a drainless peat lake in an area subjected to significant radioactive contamination after the 1986 Chernobyl accident. The 137 Cs contents in lake water and fish were two orders of magnitude greater than in local rivers and flow-through lakes, 10 years after Chernobyl radioactive contamination, and remain stable. The 137 Cs content in lake fish and a mixture of forest mushrooms was between approximately 10-20 kBq/kg, which exceeded the temporary Russian permissible levels for these products by a factor of 20-40. Consumption of lake fish gave the main contribution to internal doses (40-50%) for Kozhany village inhabitants Simple countermeasures, such as Prussian blue doses for dairy cows and pre-boiling mushrooms and fish before cooking, halved the 137 Cs internal dose to inhabitants, even 10 years after the radioactive fallout

  6. Non-Linear Dose-Response Relationships in Biology, Toxicology and Medicine - An International Conference

    Energy Technology Data Exchange (ETDEWEB)

    Calabrese, Edward J.; Kostecki, Paul T.

    2002-05-28

    Conference abstract book contains seven sections: Plenary-4 abstracts; Chemical-9 abstracts; Radiation-7 abstracts; Ultra Low Doses and Medicine-6 abstracts; Biomedical-11 abstracts; Risk Assessment-5 abstracts and Poster Sessions-25 abstracts. Each abstract was provided by the author/presenter participating in the conference.

  7. The ICRP 66 Internal Radiation Exposure Control and Dose Evaluation of The Institute of Nuclear Energy Research

    Energy Technology Data Exchange (ETDEWEB)

    Pang, H. F.; Hwang, W. S.; Chiu, J. H.

    2004-07-01

    The Atomic Energy Council (AEC) is the regulatory body of ionization radiation protection in Taiwan. To effectively control the safety in ionization radiation, AEC brought into force the Ionization Radiation Protection Act on 1 February, 2003 with clear statements of the penalty for violating the Law. The Article 5 of the Act provides: In order to limit the radiation exposure from radiation sources or practices, the Competent Authority shall refer to the latest standards of the International Commission on Radiological Protection to lay down the Safety Standards for Protection against Ionizing Radiation. Thus, AEC is going to draft new safety standards of ionization radiation protection of Taiwan according to ICRP Publication 60. The Institute of Nuclear Energy Research (INER), the governmental institute working on ionization radiation research in Taiwan, took the responsibility of assisting AEC in establishing guidelines on the control of internal radiation exposure and responding to the regulations in the new standards as soon as possible. So, according to the recommendations of ICRP Publications 60, 66,67,68,69,71,78,88, and IAEA Safety Standard Series No. RS-G- 1.1 and 1.2, INER undertook researches on the internal radiation exposure control and dose evaluations for INER's radiation workers as well as dose evaluations for the general public. The research accomplishments not only can be the reference of AEC when making new standards, but also can be followed by other radiation protection businesses. (Author) 23 refs.

  8. The ICRP 66 Internal Radiation Exposure Control and Dose Evaluation of The Institute of Nuclear Energy Research

    International Nuclear Information System (INIS)

    Pang, H. F.; Hwang, W. S.; Chiu, J. H.

    2004-01-01

    The Atomic Energy Council (AEC) is the regulatory body of ionization radiation protection in Taiwan. To effectively control the safety in ionization radiation, AEC brought into force the Ionization Radiation Protection Act on 1 February, 2003 with clear statements of the penalty for violating the Law. The Article 5 of the Act provides: In order to limit the radiation exposure from radiation sources or practices, the Competent Authority shall refer to the latest standards of the International Commission on Radiological Protection to lay down the Safety Standards for Protection against Ionizing Radiation. Thus, AEC is going to draft new safety standards of ionization radiation protection of Taiwan according to ICRP Publication 60. The Institute of Nuclear Energy Research (INER), the governmental institute working on ionization radiation research in Taiwan, took the responsibility of assisting AEC in establishing guidelines on the control of internal radiation exposure and responding to the regulations in the new standards as soon as possible. So, according to the recommendations of ICRP Publications 60, 66,67,68,69,71,78,88, and IAEA Safety Standard Series No. RS-G- 1.1 and 1.2, INER undertook researches on the internal radiation exposure control and dose evaluations for INER's radiation workers as well as dose evaluations for the general public. The research accomplishments not only can be the reference of AEC when making new standards, but also can be followed by other radiation protection businesses. (Author) 23 refs

  9. Estimation of annual dose equivalent (internal and external) for new thorium plant workers of IRE OSCOM, Orissa

    International Nuclear Information System (INIS)

    Vidya Sagar, D.; Tripathy, S.K.; Khan, A.H.; Maharana, L.N.

    2001-01-01

    In addition to thoron, thoron daughters and gamma radiation, the New Thorium Plant workers are exposed to long lived alpha emitters due to inhalation of thorium fine dust present in the working environment. Air samplers were used for measurement of thoron daughters and long lived alpha concentration. Each sample was counted for 3-4 hours for alpha activity and the long lived alpha concentration was calculated after taking the self absorption effect of the deposit on the filter paper into account. Internal dose of individual workers due to thoron daughter concentration and long lived alpha concentration was determined using time weighted factors. Based on the results, it is observed that contribution of thoron daughters, long lived alpha and external gamma is about 2 mSv /y, 1 mSv /y and 5 mSv/y, respectively, to total dose to the workers. (author)

  10. Calculation of internal dose from ingested soil-derived uranium in humans: Application of a new method

    Energy Technology Data Exchange (ETDEWEB)

    Traeber, S.C.; Li, W.B.; Hoellriegl, V.; Oeh, U. [Helmholtz Zentrum Muenchen, German Research Center for Environmental Health, Research Unit Medical Radiation Physics and Diagnostics, Neuherberg (Germany); Nebelung, K. [Friedrich Schiller University of Jena, Institute of Geosciences, Jena (Germany); Michalke, B. [Helmholtz Zentrum Muenchen, German Research Center for Environmental Health, Research Unit BioGeoChemistry and Analytics, Neuherberg (Germany); Ruehm, W. [Helmholtz Zentrum Muenchen, German Research Center for Environmental Health, Institute of Radiation Protection, Neuherberg (Germany)

    2015-08-15

    The aim of the present study was to determine the internal dose in humans after the ingestion of soil highly contaminated with uranium. Therefore, an in vitro solubility assay was performed to estimate the bioaccessibility of uranium for two types of soil. Based on the results, the corresponding bioavailabilities were assessed by using a recently published method. Finally, these bioavailability data were used together with the biokinetic model of uranium to assess the internal doses for a hypothetical but realistic scenario characterized by a daily ingestion of 10 mg of soil over 1 year. The investigated soil samples were from two former uranium mining sites of Germany with {sup 238}U concentrations of about 460 and 550 mg/kg. For these soils, the bioavailabilities of {sup 238}U were quantified as 0.18 and 0.28 % (geometric mean) with 2.5th percentiles of 0.02 and 0.03 % and 97.5th percentiles of 1.48 and 2.34 %, respectively. The corresponding calculated annual committed effective doses for the assumed scenario were 0.4 and 0.6 μSv (GM) with 2.5th percentiles of 0.2 and 0.3 μSv and 97.5th percentiles of 1.6 and 3.0 μSv, respectively. These annual committed effective doses are similar to those from natural uranium intake by food and drinking water, which is estimated to be 0.5 μSv. Based on the present experimental data and the selected ingestion scenario, the investigated soils - although highly contaminated with uranium - are not expected to pose any major health risk to humans related to radiation. (orig.)

  11. Measurement of 131I activity in air indoor Polish nuclear medical hospital as a tool for an internal dose assessment.

    Science.gov (United States)

    Brudecki, K; Szczodry, A; Mróz, T; Kowalska, A; Mietelski, J W

    2018-03-01

    This paper presents results of 131 I air activity measurements performed within nuclear medical hospitals as a tool for internal dose assessment. The study was conducted at a place of preparation and administration of 131 I ("hot room") and at a nurse station. 131 I activity measurements were performed for 5 and 4 consecutive working days, at the "hot room" and nurse station, respectively. Iodine from the air was collected by a mobile HVS-30 aerosol sampler combined with a gas sampler. Both the gaseous and aerosol fractions were measurement. The activities in the gaseous fraction ranged from (28 ± 1 Bq m -3 ) to (492 ± 4) Bq m -3 . At both sampling sites, the activity of the gaseous iodine fraction trapped on activated charcoal was significantly higher than that of the aerosol fraction captured on Petrianov filter cloth. Based on these results, an attempt has been made to estimate annual inhalation effective doses, which were found to range from 0.47 mSv (nurse female) to 1.3 mSv (technician male). The highest annual inhalation equivalent doses have been found for thyroid as 32, 27, 13, and 11 mSv, respectively, for technician male, technical female, nurse male, and nurse female. The method presented here allows to fill the gaps in internal doses measurements. Moreover, because method has been successful used for many years in radioactive contamination monitoring of air in cases of serious nuclear accidents, it should also be used in nuclear medicine.

  12. Alpha-particle doses to human organs and tissues from internally-deposited 226Ra and 228Ra

    International Nuclear Information System (INIS)

    Keane, A.T.; Schlenker, R.A.

    1981-01-01

    Estimation of radiation doses to the soft tissues from internally-deposited 226 Ra and 228 Ra is relevant to an investigation of soft-tissue malignancies in radium-exposed persons being conducted at the Center for Human Radiobiology. Alpha-particle doses in a 50-year period following a single injection of 226 Ra or 228 Ra are presented for 31 soft tissues and organs of the adult human. The dose estimates were derived from the ICRP alkaline earth model fitted to data on retention of 226 Ra in soft tissues and bone, combined with reported ratios of 226 Ra to Ca in soft tissue and bone at natural levels and the distribution of Ca in the tissues of Reference Man (ICRP23). The median of the 31 organ and tissue doses from the α-particles of 226 Ra itself is 0.08 rad per injected μCi. An additional average dose of 0.01 rad per μCi 226 Ra daughter products produced in soft tissue or transferred from bone to soft tissue. Soft-tissue doses from α-particles of the 228 Ra decay series are about six times those from 226 Ra α-particles for equal injected activities of 228 Ra and 226 Ra, with the assumption that 228 Ra daughter products do not transfer from the organ in which they are produced. The 50-year dose to the red marrow of bone from α-particles originating in bone is 0.55 rad per μCi 226 Ra injected and 1.0 rad per μCi 228 Ra injected. For ingestion by dial painters of luminous compound containg 226 Ra or 228 Ra with a daughter-to-parent activity ratio of 0.5, the dose to the mucosal alyer of the lower large intestine from α-particles originating in the gut contents is about 0.1 rad per μCi systemic intake of 226 Ra or 228 Ra

  13. Some characteristics of the retention distribution and internal doses of 59Fe in rats

    International Nuclear Information System (INIS)

    Wang Deheng; Tian Wuxun; Zhang Hongyuan; Wen Quanfa; Hu Yuexin; Zhao Shanyin

    1993-01-01

    After gastric incubation, the whole body 59 Fe-retentions in rats were fit to two compartment exponential equations. The biological half life for 59 Fe in the slow compartment are 95 and 109 days for young and adult rats respectively, not statistically significantly different. The main 59 Fe-accumulative organs are liver and bone marrow. The biological eliminations of 59 Fe from most organs in young rats are faster than in adult rats. The young rats get more total accumulative dose in organs except liver and total body and have a faster dose accumulative speed than the adult rats. Equal quantities of 59 Fe P.O. may probably give young rats more intensive biological effects than adult rats

  14. Age influence on retention, distribution and internal doses of 85Sr in rat

    International Nuclear Information System (INIS)

    Tian Wuxun; Wang Decheng; Zhang Hongyuan

    1990-01-01

    After I.V. 85 Sr, the whole body 85 Sr-retentions in rats were fit to two compartment exponential equations. The equation parameters showed a significantly difference between the young group and both the adult and old groups (p 2 ) for 85 Sr in the slow compartment decreased in regular order from the young to the old groups. In the bone 85 Sr-retention equations Tb 2 of the slow compartment for 85 Sr in the young group was significantly lower than the adult and old groups. The doses of the whole body and red-marrow for young rats were 4.2 times as much as those of adult rats, and 6.2 and 5.9 times as much as those old rats. The dose-cumulative speeds was most quick in the young groups and similar in the adult and the old

  15. Analyse of the international recommendations on the calculation of absorbed dose in the biota

    International Nuclear Information System (INIS)

    Pereira, Wagner de S.; Py Junior, Delcy de A.; Universidade Federal Fluminense; Kelecom, Alphonse

    2011-01-01

    This paper evaluates the recommendations of ICRP which has as objective the environmental radioprotection. It was analysed the recommendations 26, 60, 91, 103 and 108 of the ICRP. The ICRP-103 defined the concept of animal and plant of reference (APR) to be used in the RAP based on the calculation of absorbed dose based on APR concept. This last view allows to build a legal framework of environmental protection with a etic, moral and scientific visualization, more defensible than the anthropomorphic concept

  16. ISOE: an international occupational exposure database and communications network for dose optimisation

    International Nuclear Information System (INIS)

    Robinson, I.F.; Lazo, E.

    1995-01-01

    The Information System on Occupational Exposure (ISOE) was launched by the Nuclear Energy Agency (NEA) of the Organisation for Economic Co-operation and Development (OECD) on 1 January 1992 to facilitate the communication of dosimetry and ALARA implementation data among nuclear facilities around the world. Members of ISOE include 51 utilities from 17 countries and regulators from 11 countries, with four regional technical centres administering the system and a Steering Group which manages the work. ISOE includes three databases and a communications network at several levels. The three databases NEA1, NEA2 and NEA3 include varying levels of details, with NEA3 being the most detailed giving task and site specific ALARA practices and experiences. Utility membership of ISOE gives full access to the databases whereas regulators have more limited access. This paper reviews the current status of participation, describes the three databases and the communications network. Some dose data showing trends in particular countries are presented as well as dose data relating to operation cycle length and outage length. The advantages of membership are described, and it is concluded that ISOE holds the potential for both dose and cost savings. (author)

  17. Acquisition of biokinetic data for internal dose calculations for some novel radiopharmaceuticals

    International Nuclear Information System (INIS)

    Smith, T.; Zanelli, G.D.; Crawley, C.W.

    1986-01-01

    Estimation of radiation dose commitment, expresses as an effective dose equivalent, is a prior requisite to the application for a license to administer radiopharmaceuticals and, therefore, in the case of novel radiopharmaceuticals is leading to an increasing awareness of the need for dosimetry-orientated studies. In this laboratory potential new radiopharmaceuticals are investigated initially by animal studies to assess the possible distribution in man, and subsequently in controlled volunteer studies designed to obtain the maximum possible amount of biokinetic data to allow accurate estimation of radiation dose. A variety of techniques are used for this purpose, including profile counting, partial and whole-body scanning by LFOV gamma camera and whole-body counting, in addition to the analysis of radioactivity in blood and excreta. The use of these techniques is illustrated for the acquisition of biokinetic data and subsequent dosimetry of three novel radiopharmaceuticals: 77 Br-p-bromospiperone (quantification of dopamine receptors in the brain). 99 Tc/sup m/-porphyrins and 99 Tc/sup m/ DEPE (a possible novel blood pool marker for MUGA studies). 14 references, 14 figures, 2 tables

  18. Absorbed dose at subcellular level by Monte Carlo simulation for a {sup 99m}Tc-peptide with nuclear internalization

    Energy Technology Data Exchange (ETDEWEB)

    Rojas C, E. L.; Ferro F, G. [ININ, Carretera Mexico-Toluca s/n, Ocoyoacac 52750, Estado de Mexico (Mexico); Santos C, C. L., E-mail: leticia.rojas@inin.gob.m [Universidad Autonoma del Estado de Mexico, Paseo Tollocan esquina Paseo Colon s/n, Toluca 50120, Estado de Mexico (Mexico)

    2010-10-15

    The utility of radiolabeled peptides for the early and specific diagnosis of cancer is being investigated around the world. Recent investigations have demonstrated the specificity of {sup 99m}Tc-bombesin conjugates to target breast and prostate cancer cells. The novel idea of adding the Tat (49-57) peptide to the radiopharmaceutical in order to penetrate the cell nucleus is a new proposal for therapy at cellular level. {sup 99m}Tc radionuclide produces Auger energy of 0.9 keV/decay and internal conversion electron energy of 15.4 keV/decay, which represent 11.4% of the total {sup 99m}Tc energy released per decay. It is expected that the dose delivered at specific microscopic levels in cancer cells induce a therapeutic effect. The aim of this research was to assess in vitro internalization kinetics in breast and prostate cancer cells of {sup 99m}Tc-Tat(49-57)-bombesin and to evaluate the radiation absorbed dose at subcellular level simulating the electron transport. The pen main program from the 2006 version of the Penelope code was used to simulate and calculate the absorbed dose by Auger and internal conversion electron contribution in the membrane, cytoplasm and nucleus of Pc-3 prostate cancer and MCF7 and MDA human breast cancer cell lines. Nuclear data were obtained from the 2002 BNM-LNHB {sup 99m}Tc decay scheme. The spatial distribution of the absorbed doses to the membrane, cytoplasm and nucleus were calculated using a geometric model built from real images of cancer cells. The elemental cell composition was taken from the literature. The biokinetic data were obtained evaluating total disintegrations in each subcellular compartment by integration of the time-activity curves acquired from experimental data. Results showed that 61, 63 and 46% of total disintegrations per cell-bound {sup 99m}Tc-Tat-Bn activity unit occurred in the nucleus of Pc-3, MCF7 and MDA-MB231 respectively. {sup 99m}Tc--Tat-Bn absorbed doses were 1.78, 5.76 and 2.59 Gy/Bq in the nucleus of

  19. Development of a new mathematical model representing the head region of the adult human for use in internal dose calculations

    International Nuclear Information System (INIS)

    Facioli, L.M.

    1984-01-01

    It is presented a new mathematical model to determine the spatial distribution of the scattered radiation, or specific absorbed fractions, in the head of the adult man. The ALGAM computer code which calculates the internal dose from gamma-ray sources in a man phanton, was modified to include the model proposed. The new program was processed for two source organs: thyroid and brain for 12 incident photon energies ranging from 0.010 to 4.0 MeV. (M.C.K.) [pt

  20. Image gently, step lightly: increasing radiation dose awareness in pediatric interventions through an international social marketing campaign.

    Science.gov (United States)

    Sidhu, Manrita K; Goske, Marilyn J; Coley, Brian J; Connolly, Bairbre; Racadio, John; Yoshizumi, Terry T; Utley, Tara; Strauss, Keith J

    2009-09-01

    In the past several decades, advances in imaging and interventional techniques have been accompanied by an increase in medical radiation dose to the public. Radiation exposure is even more important in children, who are more sensitive to radiation and have a longer lifespan during which effects may manifest. To address radiation safety in pediatric computed tomography, in 2008 the Alliance for Radiation Safety in Pediatric Imaging launched an international social marketing campaign entitled Image Gently. This article describes the next phase of the Image Gently campaign, entitled Step Lightly, which focuses on radiation safety in pediatric interventional radiology.

  1. Dose to the lens of the eye when scanning internal auditory meati

    International Nuclear Information System (INIS)

    English, P.T.

    1988-01-01

    With particular reference to the lens of the eye when CT scanning the internal auditory meati (IAMs), the practice of angling the scanner gantry to avoid the orbits completely justifies itself, reducing dosage to 5% of that given by a pre-orbital scan. (author)

  2. Fission track analysis method of urine plutonium and estimation of plutonium-239 internal dose to Marshallese

    International Nuclear Information System (INIS)

    Zhao Shixuan

    1995-01-01

    Bravo detonated at Bikini Atoll on the morning of March 1, 1954, unexpectedly released a large amount of radioactive fallout on the areas. Impact studies on the radiological health and safety of the residents living in the contaminated environments are still undergoing. For plutonium dose assessment, researchers at Brookhaven National Laboratory established a fission track analysis (FTA) method for low-level 239 Pu measurement. Furthermore, a new shipboard protocol was developed for collecting 24-h radiologically clean urine samples. The purposes of this paper are to update information on the FTA processes and to present a set of results on the 239 Pu measurements in the Marshallese populations (Rongelap and Utirik) between 1981-1991. The detection sensitivity of FTA method (99% confidence level) in these samples was 2-3 μBq which is equivalent to 0.2-0.3 mSv effective dose equivalent (EDE) to age 70 for the Marshallese. The latest 1991 FTA data indicate average EDE of 0.62 mSv and 1.6 mSv for the people of Rongelap and Utirik, respectively, which both are the highest values since 1988

  3. A method for calculating Bayesian uncertainties on internal doses resulting from complex occupational exposures

    International Nuclear Information System (INIS)

    Puncher, M.; Birchall, A.; Bull, R. K.

    2012-01-01

    Estimating uncertainties on doses from bioassay data is of interest in epidemiology studies that estimate cancer risk from occupational exposures to radionuclides. Bayesian methods provide a logical framework to calculate these uncertainties. However, occupational exposures often consist of many intakes, and this can make the Bayesian calculation computationally intractable. This paper describes a novel strategy for increasing the computational speed of the calculation by simplifying the intake pattern to a single composite intake, termed as complex intake regime (CIR). In order to assess whether this approximation is accurate and fast enough for practical purposes, the method is implemented by the Weighted Likelihood Monte Carlo Sampling (WeLMoS) method and evaluated by comparing its performance with a Markov Chain Monte Carlo (MCMC) method. The MCMC method gives the full solution (all intakes are independent), but is very computationally intensive to apply routinely. Posterior distributions of model parameter values, intakes and doses are calculated for a representative sample of plutonium workers from the United Kingdom Atomic Energy cohort using the WeLMoS method with the CIR and the MCMC method. The distributions are in good agreement: posterior means and Q 0.025 and Q 0.975 quantiles are typically within 20 %. Furthermore, the WeLMoS method using the CIR converges quickly: a typical case history takes around 10-20 min on a fast workstation, whereas the MCMC method took around 12-hr. The advantages and disadvantages of the method are discussed. (authors)

  4. Evaluation of internal and external doses from $^{11}C$ produced in the air in high energy proton accelerator tunnels

    CERN Document Server

    Endo, A; Kanda, Y; Oishi, T; Kondo, K

    2001-01-01

    Air has been irradiated with high energy protons at the 12 GeV proton synchrotron to obtain the following parameters essential for the internal dose evaluation from airborne /sup 11/C produced through nuclear spallation reactions: the abundance of gaseous and particulate /sup 11/C, chemical forms, and particle size distribution. It was found that more than 98% of /sup 11/C is present as gas and the rest is aerosol. The gaseous components were only /sup 11/CO and /sup 11/CO/sub 2/ and their proportions were approximately 80% and 20%, respectively. The particulate /sup 11/C was found to be sulphate and/or nitrate aerosols having a log-normal size distribution; the measurement using a diffusion battery showed a geometric mean radius of 0.035 mu m and a geometric standard deviation of 1.8 at a beam intensity of 6.8*10/sup 11/ proton.pulse /sup -1/ and an irradiation time of 9.6 min. By taking the chemical composition and particle size into account, effective doses both from internal and from external exposures pe...

  5. Development of a new mathematical model of an adult man head for using in internal dose calculation

    International Nuclear Information System (INIS)

    Facioli, L.M.; Deus, S.F.

    1986-01-01

    A new mathematical model representing the head region of the adult man had been developed in a more realistic fashion than the existing models in order to achieve an improvement in the accuracy of the internal dose calculations. The specific absorbed fractions had been obtained by program 'ALGAM: a computer program for estimating internal dose from gamma-ray sources in a man phantom', which had been modified to include the model proposed in this work. The new program had been processed for two source organs: thyroid and brain and for 12 incident photon energies ranging from 0,010 to 4,0 MeV. The obtained results, when compared with the Snyder's one, show that the ratio of the specific absorbed fractions in the common organs of the model proposed in this work relative to the Snyder's model, ranged from 0,0543 to 13,2 for the two source organs considered; the ratio distribution along this interval is practically uniform between the above values. (Author) [pt

  6. Urethral dose and increment of international prostate symptom score (IPSS) in transperineal permanent interstitial implant (TPI) of prostate cancer

    International Nuclear Information System (INIS)

    Murakami, N.; Itami, J.; Okuma, K.; Marino, H.; Ban, T.; Nakazato, M.; Kanai, K.; Naoi, K.; Fuse, M.; Nakagawa, K.

    2008-01-01

    Purpose: to find the factors which influence the acute increment of international prostate symptom score (IPSS) after transperineal permanent interstitial implant (TPI) using 125 I seeds. Patients and methods: from April 2004 through September 2006, 104 patients with nonmetastatic prostate cancer underwent TPI without external-beam irradiation. Median patient age was 70 years with a median follow-up of 13.0 months. 73 patients (70%) received neoadjuvant hormone therapy. The increment of IPSS was defined as the difference between pre- and postimplant maximal IPSS. Clinical, treatment, and dosimetric parameters evaluated included age, initial prostate-specific antigen, Gleason Score, neoadjuvant hormone therapy, initial IPSS, post-TPI prostatic volume, number of implanted seeds, prostate V 100 , V 150 , D 90 , urethral D max , and urethral D 90 . In order to further evaluate detailed urethral doses, the base and apical urethra were defined and the dosimetric parameters were calculated. Results: the IPSS peaked 3 months after TPI and returned to baseline at 12-15 months. Multivariate analysis demonstrated a statistically significant correlation of post-TPI prostatic volume, number of implanted seeds, and the dosimetric parameters of the base urethra with IPSS increment. Conclusion: the base urethra appears to be susceptible to radiation and the increased dose to this region deteriorates IPSS. It remains unclear whether the base urethral dose relates to the incidence of late urinary morbidities. (orig.)

  7. Modern Radiation Therapy for Hodgkin Lymphoma: Field and Dose Guidelines From the International Lymphoma Radiation Oncology Group (ILROG)

    International Nuclear Information System (INIS)

    Specht, Lena; Yahalom, Joachim; Illidge, Tim; Berthelsen, Anne Kiil; Constine, Louis S.; Eich, Hans Theodor; Girinsky, Theodore; Hoppe, Richard T.; Mauch, Peter; Mikhaeel, N. George; Ng, Andrea

    2014-01-01

    Radiation therapy (RT) is the most effective single modality for local control of Hodgkin lymphoma (HL) and an important component of therapy for many patients. These guidelines have been developed to address the use of RT in HL in the modern era of combined modality treatment. The role of reduced volumes and doses is addressed, integrating modern imaging with 3-dimensional (3D) planning and advanced techniques of treatment delivery. The previously applied extended field (EF) and original involved field (IF) techniques, which treated larger volumes based on nodal stations, have now been replaced by the use of limited volumes, based solely on detectable nodal (and extranodal extension) involvement at presentation, using contrast-enhanced computed tomography, positron emission tomography/computed tomography, magnetic resonance imaging, or a combination of these techniques. The International Commission on Radiation Units and Measurements concepts of gross tumor volume, clinical target volume, internal target volume, and planning target volume are used for defining the targeted volumes. Newer treatment techniques, including intensity modulated radiation therapy, breath-hold, image guided radiation therapy, and 4-dimensional imaging, should be implemented when their use is expected to decrease significantly the risk for normal tissue damage while still achieving the primary goal of local tumor control. The highly conformal involved node radiation therapy (INRT), recently introduced for patients for whom optimal imaging is available, is explained. A new concept, involved site radiation therapy (ISRT), is introduced as the standard conformal therapy for the scenario, commonly encountered, wherein optimal imaging is not available. There is increasing evidence that RT doses used in the past are higher than necessary for disease control in this era of combined modality therapy. The use of INRT and of lower doses in early-stage HL is supported by available data. Although the

  8. Direct measurements of employees involved in the Fukushima Daiichi Nuclear Power Station accident for internal dose estimates. JAEA's experiences

    Energy Technology Data Exchange (ETDEWEB)

    Kurihara, Osamu; Kanai, Katsuta; Nakagawa, Takahiro; Takada, Chie; Momose, Takumaro; Furuta, Sadaaki [Japan Atomic Energy Agency, Nuclear Fuel Cycle Engineering Laboratories, Tokai, Ibaraki (Japan)

    2012-11-15

    Japan Atomic Energy Agency (JAEA) performed internal dose measurements of employees involved in the Fukushima Daiichi nuclear power station accident. Nuclear Fuel Cycle Engineering Laboratories (NFCEL), one of the JAEA's core centers, examined 560 of these employees by direct (in vivo) measurements during the period from April 20 to August 5 in 2011. These measurements consisted of whole-body counting for radiocesium and thyroid counting for radioiodine. The whole-body counting was conducted with two types of whole-body counters (WBCs): a standing-type WBC with two large NaI(Tl) detectors (Fastscan{sup TM}, Canberra Inc.) and a chair-type WBC with HPGe detectors (GC5021, Canberra Inc.) installed in a shielded chamber made of 20-cm-thick steel. The thyroid counting was mainly performed using one of the two HPGe detectors equipped with the chair-type WBC. The subjects examined in this work were divided into two groups: Group 1 was the first 39 subjects who were measured up to June 17, 2011 and Group 2 was the remaining 521 subjects who were measured on and after June 18, 2011. The performance of our direct measurements was validated by comparing measurement results of the Group 1 subjects using two different methods (e.g., the standing-type WBC vs. the chair-type WBC). Tentative internal dose estimates of the subjects of Group 1 were also performed based on the assumption of a single intake scenario on either March 12, when the first hydrogen explosion occurred at the station or the first day of work after the accident. It was found that the contribution of {sup 131}I to the total internal dose greatly exceeded those of {sup 134}Cs and {sup 137}Cs, the other major nuclides detected in the measurements. The maximum committed effective dose (CED) was found in a male subject whose thyroid content of {sup 131}I was 9760 Bq on May 23, 2011; the CED of this subject was estimated to be 600 mSv including a small contribution of {sup 134}Cs and {sup 137}Cs. The typical

  9. 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

  10. Radioactive caesium in a boreal forest ecosystem and internally absorbed dose to man

    International Nuclear Information System (INIS)

    Bergman, R.; Johansson, L.

    1989-01-01

    Different aspects dealing with water-soil, soil-plant and plant-herbivore interactions are studied. The study area is located to the Forest Research Station at Svartberget 50 km west of Umea in Vaesterbotten. An important topic in this study concerns the transport of caesium in food chains to man. Consumption of forest products by man i.e. game (primarily moose) and berries constitutes the major pathway of radioactive caesium to man. Moose meat contributes to about 30% of the total meat consumption in Vaesterbotten and the average over the Swedish population has remained at the level of 5-10% during the present decade. In order to assess the absorbed dose resulting from intake via these food products over a long period of time, knowledge about the long term behaviour of caesium in the biotic community is studied. (orig./HP)

  11. Evaluating the Application of Tissue-Specific Dose Kernels Instead of Water Dose Kernels in Internal Dosimetry : A Monte Carlo Study

    NARCIS (Netherlands)

    Moghadam, Maryam Khazaee; Asl, Alireza Kamali; Geramifar, Parham; Zaidi, Habib

    2016-01-01

    Purpose: The aim of this work is to evaluate the application of tissue-specific dose kernels instead of water dose kernels to improve the accuracy of patient-specific dosimetry by taking tissue heterogeneities into consideration. Materials and Methods: Tissue-specific dose point kernels (DPKs) and

  12. Internal and external generalizability of temporal dose-response relationships for xerostomia following IMRT for head and neck cancer.

    Science.gov (United States)

    Thor, Maria; Owosho, Adepitan A; Clark, Haley D; Oh, Jung Hun; Riaz, Nadeem; Hovan, Allan; Tsai, Jillian; Thomas, Steven D; Yom, Sae Hee K; Wu, Jonn S; Huryn, Joseph M; Moiseenko, Vitali; Lee, Nancy Y; Estilo, Cherry L; Deasy, Joseph O

    2017-02-01

    To study internal and external generalizability of temporal dose-response relationships for xerostomia after intensity-modulated radiotherapy (IMRT) for head and neck cancer, and to investigate potential amendments of the QUANTEC guidelines. Objective xerostomia was assessed in 121 patients (n Cohort1 =55; n Cohort2 =66) treated to 70Gy@2Gy in 2006-2015. Univariate and multivariate analyses (UVA, MVA with 1000 bootstrap populations) were conducted in Cohort1, and generalizability of the best-performing MVA model was investigated in Cohort2 (performance: AUC, p-values, and Hosmer-Lemeshow p-values (p HL )). Ultimately and for clinical guidance, minimum mean dose thresholds to the contralateral and the ipsilateral parotid glands (Dmean contra , Dmean ipsi ) were estimated from the generated dose-response curves. The observed xerostomia rate was 38%/47% (3months) and 19%/23% (11-12months) in Cohort1/Cohort2. Risk of xerostomia at 3months increased for higher Dmean contra and Dmean ipsi (Cohort1: 0.17·Dmean contra +0.11·Dmean ipsi -8.13; AUC=0.90±0.05; p=0.0002±0.002; p HL =0.22±0.23; Cohort2: AUC=0.81; pxerostomia following IMRT. Our results also suggest decreasing Dmean contra to below 20Gy, while keeping Dmean ipsi to around 25Gy. Long-term xerostomia was less frequent, and no dose-response relationship was established for this follow-up time. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  13. A comparative evaluation of the consequences of the Chernobyl accident based on the internal dose of {sup 137}Cs to Japanese male adults

    Energy Technology Data Exchange (ETDEWEB)

    Uchiyama, M; Ishikawa, T; Matsumoto, M; Kobayashi, S [National Inst. of Radiological Sciences, Ibaraki (Japan)

    1997-09-01

    The Chernobyl accident released a large quantity of radionuclides into the environment. Many measurements were carried out to assess the consequent radiation doses around the world. The measurements of subjects from different countries at a given institution can serve for the comparative evaluation of their internal doses when one apparatus is used consistently for the measurements. We have measured radiocesium body burdens of both Japanese and foreigners since the Chernobyl accident using a whole-body counter. In the occasion of 10th anniversary of the accident, we evaluated the body burdens in order to compare the internal doses among countries. 5 refs, 3 figs.

  14. A comparative evaluation of the consequences of the Chernobyl accident based on the internal dose of 137Cs to Japanese male adults

    International Nuclear Information System (INIS)

    Uchiyama, M.; Ishikawa, T.; Matsumoto, M.; Kobayashi, S.

    1997-01-01

    The Chernobyl accident released a large quantity of radionuclides into the environment. Many measurements were carried out to assess the consequent radiation doses around the world. The measurements of subjects from different countries at a given institution can serve for the comparative evaluation of their internal doses when one apparatus is used consistently for the measurements. We have measured radiocesium body burdens of both Japanese and foreigners since the Chernobyl accident using a whole-body counter. In the occasion of 10th anniversary of the accident, we evaluated the body burdens in order to compare the internal doses among countries. 5 refs, 3 figs

  15. Radiocesium contamination and estimated internal exposure doses in edible wild plants in Kawauchi Village following the Fukushima nuclear disaster.

    Directory of Open Access Journals (Sweden)

    Rimi Tsuchiya

    Full Text Available Kawauchi Village, in Fukushima Prefecture, is located within a 30-km radius of the nuclear disaster site of the Fukushima Daiichi Nuclear Power Plant (FDNPP. "Sansai" (edible wild plants in this village have been evaluated by gamma spectrometry after the residents had returned to their homes, to determine the residents' risk of internal exposure to artificial radionuclides due to consumption of these plants. The concentrations of radiocesium (cesium-134 and cesium-137 were measured in all 364 samples collected in spring 2015. Overall, 34 (9.3% samples exceeded the regulatory limit of 100 Bq/kg established by Japanese guidelines, 80 (22.0% samples registered between 100 Bq/kg and 20 Bq/kg, and 250 (68.7% registered below 20 Bq/kg (the detection limit. The internal effective doses from edible wild plants were sufficiently low (less than 1 mSv/y, at 3.5±1.2 μSv/y for males and 3.2±0.9 μSv/y for females (2.7±1.5 μSv/y for children and 3.7±0.7 μSv/y for adults in 2015. Thus, the potential internal exposure doses due to consumption of these edible wild plants were below the applicable radiological standard limits for foods. However, high radiocesium levels were confirmed in specific species, such as Eleutherococcus sciadophylloides ("Koshiabura" and Osmunda japonica (Asian royal fern, "Zenmai". Consequently, a need still might exist for long-term follow-up such as environmental monitoring, physical and mental support to avoid unnecessary radiation exposure and to remove anxiety about adverse health effects due to radiation. The customs of residents, especially the "satoyama" (countryside culture of ingesting "sansai," also require consideration in the further reconstruction of areas such as Kawauchi Village that were affected by the nuclear disaster.

  16. Telemedicine-guided, very low-dose international normalized ratio self-control in patients with mechanical heart valve implants.

    Science.gov (United States)

    Koertke, Heinrich; Zittermann, Armin; Wagner, Otto; Secer, Songuel; Sciangula, Alfonso; Saggau, Werner; Sack, Falk-Udo; Ennker, Jürgen; Cremer, Jochen; Musumeci, Francesco; Gummert, Jan F

    2015-06-01

    To study in patients performing international normalized ratio (INR) self-control the efficacy and safety of an INR target range of 1.6-2.1 for aortic valve replacement (AVR) and 2.0-2.5 for mitral valve replacement (MVR) or double valve replacement (DVR). In total, 1304 patients undergoing AVR, 189 undergoing MVR and 78 undergoing DVR were randomly assigned to low-dose INR self-control (LOW group) (INR target range, AVR: 1.8-2.8; MVR/DVR: 2.5-3.5) or very low-dose INR self-control once a week (VLO group) and twice a week (VLT group) (INR target range, AVR: 1.6-2.1; MVR/DVR: 2.0-2.5), with electronically guided transfer of INR values. We compared grade III complications (major bleeding and thrombotic events; primary end-points) and overall mortality (secondary end-point) across the three treatment groups. Two-year freedom from bleedings in the LOW, VLO, and VLT groups was 96.3, 98.6, and 99.1%, respectively (P = 0.008). The corresponding values for thrombotic events were 99.0, 99.8, and 98.9%, respectively (P = 0.258). The risk-adjusted composite of grade III complications was in the per-protocol population (reference: LOW-dose group) as follows: hazard ratio = 0.307 (95% CI: 0.102-0.926; P = 0.036) for the VLO group and = 0.241 (95% CI: 0.070-0.836; P = 0.025) for the VLT group. The corresponding values of 2-year mortality were = 1.685 (95% CI: 0.473-5.996; P = 0.421) for the VLO group and = 4.70 (95% CI: 1.62-13.60; P = 0.004) for the VLT group. Telemedicine-guided very low-dose INR self-control is comparable with low-dose INR in thrombotic risk, and is superior in bleeding risk. Weekly testing is sufficient. Given the small number of MVR and DVR patients, results are only valid for AVR patients. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.

  17. First Italian intercomparison on methodologies for dose assessment from internal contamination. Results and perspectives; Primo interconfronto italiano sulle metodiche di valutazione di dose da contaminazione interna: risultati e prospettive

    Energy Technology Data Exchange (ETDEWEB)

    Castellani, C.M.; Battisti, P.; Tarroni [ENEA, Centro Ricerche Ezio Clementel, Bologna (Italy). Dipt. Ambiente

    1998-07-01

    In the frame of the MIDIA activities (coordination of whole body counters operating in Italy) an intercomparison on dose evaluation methods was promoted and carried out between October 1995 and March 1996 by 5 WBC centres. The main results related to the estimation of Intake and effective dose equivalent on the four case studies are reported. A comparison with European preliminary results is also presented. Finally perspectives related to the quality assurance of internal dosimetry estimates are indicated. [Italian] Vengono riportati i risultati delle valutazioni di Intake e di equivalente di dose nei centri MIDIA (coordinamento dei WBC operanti in Italia) per effettuare un interconfronto sui metodi di valutazione di dose da contaminazione interna utilizzando casi di studio reperiti in ambiente europeo. Vengono indicate le prospettive per la valutazione della qualita' della stima di dose in dosimetria interna.

  18. Survey of image quality and patient dose in simple radiographic examinations: establishing guidance levels and comparison with international standards

    International Nuclear Information System (INIS)

    Manatrakul, N.; Bunsoong, T.; Krisanachinda, A.; Suwanpradit, P.; Rungruengthanakit, P.; Kanchart, S.; Chaiwong, Rajikorn; Tsapakig, V.A.

    2008-01-01

    Purpose: To investigate image quality and patient dose for commonly radiographic examinations in Thailand, to establish national reference or guidance levels (GL) and compare with international standards, as part of an International Atomic Energy Agency (IAEA) project on Radiation Protection of Patients and Medical Exposure Control (RAS/9/034 and RAS/9/047). Materials and Methods: Film reject rate analysis, image quality and patient dose assessment before and after Quality Control (QC) implementation were investigated in 8 X-ray machines in 4 hospitals. Air kerma (in mGy) at 1 meter focus-detector-distance for different kVp settings for each X-ray machines were measured using an ionization chamber under standardized condition. The entrance skin air kerma (ESAK) for Chest PA, Lumbar spine AP, Lumbar spine LAT, Pelvis AP, Abdomen AP, Skull AP and Skull LAT were calculated for at least 10 adult patients of average body mass (60 to 80 kg) for each projection. The obtained values were compared with international standards. Results: The highest film rejection rate reduction recorded after corrective actions from 9.15% to 6.8%. Mean ESAK values were less than international standards both before and after QC implementation in all projections but Chest PA projection. Maximum ESAK in Chest PA projection before corrective action was 0.55 mGy which was higher than the IAEA GL of 0.2 mGy. However, it was reduced to 0.25 mGy after QC tests on X- ray machine and using high kilovoltage (kV) technique. Conclusion: Proposed national GL of Thailand were obtained by estimating the 3rd quartile of the whole sample: Chest PA: 0.1 mGy, Lumbar Spine AP: 2.1 mGy, Lumbar Spine LAT: 6.3 mGy, Pelvis AP: 1.8 mGy, Abdomen: 1.5 mGy, Skull PA: 1.3 mGy and Skull LAT: 0.9 mGy. (author)

  19. Development of mathematical phantoms for calculating internal doses from radiopharmaceuticals using patients' digital picture of bone scintillation

    International Nuclear Information System (INIS)

    Akahane, K.; Kai, M.; Kusama, T.

    1996-01-01

    We made a new mathematical phantom using the patients' digital pictures of bone scintillation in nuclear medicine. The data of 99m Tc bone scintillation pictures include the information on the body sizes and shapes. In the bone scintillation pictures, no three dimensional data are available, so that the shapes and sizes of whole body and bones were modelled based on standard anatomical geometry. The organs except bone were also modelled after construction of the bone mathematical model. The mathematical phantoms were developed for each patient. The specific effective energy for each phantom can be calculated by the Monte Carlo code to compare it among the patients. Our mathematical phantoms would provide new calculation of internal doses from radiopharmaceuticals in place of the MIRD phantom. (author)

  20. Development of a computational code for the internal doses assessment of the main radionuclides of occupational exposure at IPEN

    International Nuclear Information System (INIS)

    Claro, Thiago Ribeiro

    2011-01-01

    The dose resulting from internal contamination can be estimated with the use of biokinetic models combined with experimental results obtained from bioanalysis and assessment of the time of incorporation. The biokinetics models are represented by a set of compartments expressing the transportation, retention and elimination of radionuclides from the body. The ICRP publications, number 66, 78 and 100, present compartmental models for the respiratory tract, gastrointestinal tract and for systemic distribution for an array of radionuclides of interest for the radiological protection. The objective of this work is to develop a computational code for the internal doses assessment of the main radionuclides of occupational exposure at IPEN. Consequently serving as a agile and efficient tool for the designing, visualization and resolution of compartmental models of any nature. The architecture of the system was conceived containing two independent software: CBT - responsible for the setup and manipulation of models and SSID - responsible for the mathematical solution of the models. Four different techniques are offered for the resolution of system of equations, including semi-analytical and numerical methods, allowing for comparison of precision and performance of both. The software was developed in C≠ programming, using a Microsoft Access database and XML standards for file exchange with other applications. Compartmental models for uranium, thorium and iodine radionuclides were generated for the validation of the CBT software. The models were subsequently solved via SSID software and the results compared with the values published in the issue 78 of ICRP. In all cases the system replicated the values published by ICRP. (author)

  1. DOSIS & DOSIS 3D: long-term dose monitoring onboard the Columbus Laboratory of the International Space Station (ISS

    Directory of Open Access Journals (Sweden)

    Berger Thomas

    2016-01-01

    Full Text Available The radiation environment encountered in space differs in nature from that on Earth, consisting mostly of highly energetic ions from protons up to iron, resulting in radiation levels far exceeding the ones present on Earth for occupational radiation workers. Since the beginning of the space era, the radiation exposure during space missions has been monitored with various active and passive radiation instruments. Also onboard the International Space Station (ISS, a number of area monitoring devices provide data related to the spatial and temporal variation of the radiation field in and outside the ISS. The aim of the DOSIS (2009–2011 and the DOSIS 3D (2012–ongoing experiments was and is to measure the radiation environment within the European Columbus Laboratory of the ISS. These measurements are, on the one hand, performed with passive radiation detectors mounted at 11 locations within Columbus for the determination of the spatial distribution of the radiation field parameters and, on the other, with two active radiation detectors mounted at a fixed position inside Columbus for the determination of the temporal variation of the radiation field parameters. Data measured with passive radiation detectors showed that the absorbed dose values inside the Columbus Laboratory follow a pattern, based on the local shielding configuration of the radiation detectors, with minimum dose values observed in the year 2010 of 195–270 μGy/day and maximum values observed in the year 2012 with values ranging from 260 to 360 μGy/day. The absorbed dose is modulated by (a the variation in solar activity and (b the changes in ISS altitude.

  2. Internal Dosimetry Monitoring- Detection Limits for a Selected Set of Radionuclides and Their Translation Into Committed Effective Dose

    International Nuclear Information System (INIS)

    Brandl, A.; Hrnecek, E.; Steger, F.

    2004-01-01

    To harmonize the practice of internal dosimetry monitoring across the country, the Austrian Standards Institute is currently drafting a new set of standards which are concerned with occupational incorporation monitoring of individuals handling non-sealed radioactive material. This set of standards is expected to consist of three parts discussing the general necessity and frequency, the requirements for monitoring institutions, and the determination and rigorous calculation of committed effective dose after incorporation of radioactive material, respectively. Considerations of the requirements for routine monitoring laboratories have led to an evaluation of the detection limits for routine monitoring equipment. For a selected set of radionuclides, these detection limits are investigated in detail. The main emphasis is placed on the decay chains of naturally occurring radionuclides showing some significant potential for being out of equilibrium due to chemical processes in certain mining industries. The radionuclides considered in this paper are 226Ra, 228Ra, 228Th, 232Th, 234U, 235U, and 238U. Given the routine monitoring intervals of the Austrian Standard, these detection limits are translated into information on committed effective dose. This paper investigates whether routine monitoring equipment is sufficient to ensure compliance with EC directive 96/29/Euratom for this selected set of radionuclides. (Author) 9 refs

  3. Prevention of fatal postoperative pulmonary embolism by low doses of heparin. An international multicentre trial.

    Science.gov (United States)

    1975-07-12

    The efficacy of low-dose heparin in preventing fatal postoperative pulmonary embolism has been investigated in a multicentre prospective randomised trial. 4121 patients over the age of forty years undergoing a variety of elective major surgical procedures were included in the trial; 2076 of these were in the control group and 2045 patients received heparin. The two groups were well matched for age, sex, weight, blood-group, and other factors which could predispose to the development of venous thromboembolism. 180 (4-4 %) patients died during the postoperative period, 100 in the control and 80 in the heparin group: 72% of deaths in the control and 66% in the heparin group had necropsy examination. 16 patients in the control group and 2 in the heparin group were found at necropsy to have died due to acute massive pulmonary embolism (P smaller than 0-005). In addition, emboli found at necropsy in 6 patients in the control group and 3 in the heparin group were considered either contributory to death or an incidental finding since death in these patients was attributed to other causes. Taking all pulmonary emboli together, the findings were again significant (P smaller than 0-005). Of 1292 patients in whom the 125-I-fibrinogen test was performed to detect deep-vein thrombosis (D.V.T.) 667 were in the control group and 625 in the heparin group. The frequency of isotopic D.V.T. was reduced from 24-6% in the control group 7-7% in the heparin group (P smaller 0-005). In 30 patients D.V.T. was detected at necropsy; 24 in the control and 6 in the heparin group (P smaller 0-005). 32 patients in the control group and 11 in the heparin group developed clinically diagnosed D.V.T. which was confirmed by venography (P smaller than 0-005). In addition, 24 patients in the control and 8 in the heparin group were treated for clinically suspected pulmonary emoblism. The difference in the number of patients requiring treatment for D.V.T. and/or pulmonary embolism in the two groups was

  4. Assessment of the efficacy of a novel tailored vitamin K dosing regimen in lowering the International Normalised Ratio in over-anticoagulated patients: a randomised clinical trial.

    Science.gov (United States)

    Kampouraki, Emmanouela; Avery, Peter J; Wynne, Hilary; Biss, Tina; Hanley, John; Talks, Kate; Kamali, Farhad

    2017-09-01

    Current guidelines advocate using fixed-doses of oral vitamin K to reverse excessive anticoagulation in warfarinised patients who are either asymptomatic or have minor bleeds. Over-anticoagulated patients present with a wide range of International Normalised Ratio (INR) values and response to fixed doses of vitamin K varies. Consequently a significant proportion of patients remain outside their target INR after vitamin K administration, making them prone to either haemorrhage or thromboembolism. We compared the performance of a novel tailored vitamin K dosing regimen to that of a fixed-dose regimen with the primary measure being the proportion of over-anticoagulated patients returning to their target INR within 24 h. One hundred and eighty-one patients with an index INR > 6·0 (asymptomatic or with minor bleeding) were randomly allocated to receive oral administration of either a tailored dose (based upon index INR and body surface area) or a fixed-dose (1 or 2 mg) of vitamin K. A greater proportion of patients treated with the tailored dose returned to within target INR range compared to the fixed-dose regimen (68·9% vs. 52·8%; P = 0·026), whilst a smaller proportion of patients remained above target INR range (12·2% vs. 34·0%; P vitamin K dosing is more accurate than fixed-dose regimen in lowering INR to within target range in excessively anticoagulated patients. © 2017 John Wiley & Sons Ltd.

  5. Proceedings of the 8. LOWRAD: International conference on the effects of low doses and very low doses of ionizing radiation on human health and biotopes

    International Nuclear Information System (INIS)

    2009-01-01

    Theoretical and experimental papers are presented in these proceedings covering the following subjects: radiation protection, dosimetry, radiation dosimetry, cells, technetium, plutonium, uranium, thorium, low dose irradiation, radiation doses, cesium, radiation chemistry, nuclear medicine, safety and occupational exposure, neoplasm, cytology and radioisotopes

  6. Prediction of the maximum dosage to man from the fallout of nuclear devices V. Estimation of the maximum dose from internal emitters in aquatic food supply

    International Nuclear Information System (INIS)

    Tamplin, A.R.; Fisher, H.L.; Chapman, W.H.

    1968-01-01

    A method is described for estimating the maximum internal dose that could result from the radionuclides released to an aquatic environment. By means of this analysis one can identify the nuclides that could contribute most to the internal dose, and determine the contribution of each nuclide to the total dose. The calculations required to estimate the maximum dose to an infant's bone subsequent to the construction of a sea-level canal are presented to illustrate the overall method. The results are shown to serve the basic aims of preshot rad-safe analysis and of guidance for postshot documentation. The usefulness of the analysis in providing guidance for device design is further pointed out. (author)

  7. Internal doses of French adult population linked to the intake of radionuclides from the decay-chains of uranium and thorium by foodstuffs ingestion

    International Nuclear Information System (INIS)

    Renaud, Ph.; Parache, V.; Roussel-Debet, S.

    2015-01-01

    This study provides the first dose assessment to the French adult population due to the intake of radionuclides from the decay chains of uranium and thorium by foodstuff ingestion (water consumption excepted). This dose varies widely with the consumption of seafood, from less than 200 μSv.y -1 for people who do not consume shellfish or crustaceans at all, to more than 2,000 μSv.y -1 for the biggest consumers (about 150 kg.y -1 according to specific dietary surveys carried out along the French seaside). For moderate consumers of seafood (around 4.6 kg.y -1 ), who probably represent a major part of the population, this internal dose would be around 330 μSv.y -1 . This variable consumption of seafood overshadows all the other causes of variability of these internal dose estimates. (authors)

  8. A study on the estimation method of internal stresses caused by the difference of thermal expansion coefficients between concrete and reinforcement at elevated temperatures

    International Nuclear Information System (INIS)

    Kanazu, Tsutomu

    1998-01-01

    When a reinforced concrete member is exposed to high temperature conditions over 100degC, tensile strain occurs in the concrete and compressive strain occurs in reinforcements due to a difference of thermal expansion coefficients between concrete and reinforcement. Its mechanism is the same as that of restrained stress caused by drying shrinkage of concrete; tensile stress occurs in the concrete because drying shrinkage strain is restrained by reinforcements, but there is a different point that the phenomenon at a high temperature condition includes the change of mechanical properties of concrete and reinforcement. In the study, the phenomenon is measured in the experiments and is clarified quantitatively. Moreover, the estimation method, which is derived from expanding the equation of average strain of reinforcement in the CEB Design Manual, is suggested and is verified by the comparison with the experimental results. (author)

  9. Total internal conversion coefficient of the 260. 9 keV (7/sup +/->3/sup -/) transition in sup(198m)Tl

    Energy Technology Data Exchange (ETDEWEB)

    Venkateswara Rao, N.; Suryanarayana, C.; Narayana, D.G.S.; Bhuloka Reddy, S.; Satynarayana, G.; Sastry, D.L.; Chintalapudi, S.N.

    1986-02-21

    The 1.87 hours 543.7 keV (7/sup +/) isomeric state in /sup 198/Tl is produced via /sup 197/Au(..cap alpha.., 3n)sup(198m)Tl (Esub(..cap alpha..) = 35 MeV) reaction. The total conversion coefficient of 260.9 keV (7/sup +/ -> 3/sup -/) is determined for the first time by the intensity balance method. The value of ..cap alpha..sub(T)(260.9 keV) is found to be 40.1 +- 8.6 which is in good agreement with the theoretical value of Hager and Seltzer for pure M4 transition. The gamma transition probability of the 260.9 keV (M4) is calculated using the present value of ..cap alpha..sub(T) and compared with the single-particle estimate.

  10. Retrospective assessment of internal doses for short-term visitors to Fukushima within one month after the nuclear power plant accident

    Energy Technology Data Exchange (ETDEWEB)

    Matsuda, Naoki [Nagasaki Univ., Center for Frontier Life Sciences, Nagasaki, Nagasaki (Japan); Kumagai, Atsushi; Ohtsuru, Akira [Fukushima Medical University, Fukushima, Fukushima (Japan); Morita, Naoko; Miura, Miwa; Yoshida, Masahiro; Kudo, Takashi; Takamura, Noboru; Yamashita, Shunichi [Nagasaki Univ., Graduate School of Biomedical Sciences, Nagasaki, Nagasaki (Japan)

    2012-11-15

    Short-term visitors to Fukushima have been monitored for internal exposure by using the whole body counter of the Nagasaki University Medical School. The total number of subjects exceeds 900 at the end of July, 2012. The highest committed effective dose and thyroid equivalent dose in 173 people who stayed in Fukushima during March 11th to April 10th, 2011 were assessed around 1 mSv and 20 mSv, respectively. (author)

  11. Main internal dose-forming factors for inhabitants of contaminated regions at current phase of the Chernobyl nuclear power plant accident (Kyiv region as an example)

    International Nuclear Information System (INIS)

    Vasilenko, V.V.; Nechajev, S.Yu.; Tsigankov, M.Ya.; And others

    2015-01-01

    Objective of this work is revealing of main dose"forming factors of internal doses for inhabitants of contaminated regions of Kyiv region relying on the results of integral dosimetric monitoring. Three villages have been chosen for the investigation. They are: Raghivka, Zelena Poliana (Poliske district), Karpylivka (Ivankiv district). Twice a year, in May and in October those villages' residents were inspected for content of incorporated "1"3"7Cs. They were measured by direct method at the place of residence with the help of whole body counters (WBC). The principal food samples were collected for detection of "9"0Sr and "1"3"7Cs content. Those villages' inhabitants were interviewed about food consumption levels. Mathematical, dosimetric and radio-chemical methods were used in this work. The estimation of internal doses due to intake of "1"3"7Cs by ingestion of milk and potatoes are in the range 0.3-34% of doses estimated on the base of WBC data. The contribution to the dose of internal exposure from intake of "1"3"7Cs with the milk consumption is no more than two times higher than the contribution of potatoes consumption in the case of equal consumption levels of these products. Contributions to the dose of internal exposure from intake of "9"0Sr with milk and potatoes consumptions are approximately similar. Consumption of mushrooms and other wild nature products by inhabitants from the inspected settlements is the main forming factor of internal dose due to "1"3"7Cs intake

  12. Methodical approach to reconstruct individual internal doses for persons residing in areas of Belarus contaminated as a result of the Chernobyl accident

    International Nuclear Information System (INIS)

    Skryabin, Anatoly; Belsky, Yuri

    2008-01-01

    Full text: The studies on the risk to population of low-level exposure following the Chernobyl accident require the estimation of the individual doses. The most difficult aspect is the estimation of internal exposure (IAED int ). Level of individual internal exposure due to ingestion of long-lived caesium isotopes defines by individual 'food habits' (IFH) of the person. Non-standard methodical approach is suggested to evaluate internal doses taking into IFH: 1) IFH are generally conservative by food characteristic and steady in time; 2) IFH of the person determines his dose which can be calculated using data of personal interview and the special table of conformity establishing connection between IFH and corresponding percentile interval in a variation line of doses in given settlement; 3) IAED int (1986-2005) is calculated as the sum of annual doses of the individual for all period of exposure and in all settlements of residing. To develop the model, WBC measurements data (around 1.5 millions) collected in 1987-2005 for population of around 1000 Belarusian settlements were used. The input data for IAEA int calculation include consumption of dose-significant products, duration, and place of residence obtained by mean of individual questionnaire; WBC measurements data; table of conformity (IFH → IAED int ). (author)

  13. The Management of Patients with Chronic Subdural Hematoma Treated with Low-Dose Acetylsalicylic Acid: An International Survey of Practice.

    Science.gov (United States)

    Soleman, Jehuda; Kamenova, Maria; Guzman, Raphael; Mariani, Luigi

    2017-11-01

    The aim of this international survey was to investigate the current management of patients undergoing surgery for chronic subdural hematoma (cSDH) treated with low-dose acetylsalicylic acid (ASA). We administered a survey via e-mail to neurosurgeons with questions relating to the surgical treatment of cSDH, emphasizing their practices with patients treated with low-dose ASA. We received 157 responses, with a response rate of 22.4%. Almost 80% of the responders discontinue ASA treatment at least 5 days before surgery and 80.7% resume treatment after 5 days or more, and 27.6% discontinue treatment for at least 30 days. The main factor influencing ASA resumption time is the indication for ASA (54.5%), and postoperative imaging is concluded in 71.7%, Postoperative thrombosis prophylaxis is administered by 60% of the responders, and 50% apply it 24 hours after surgery. Almost 95% of the responders believe that better evidence is needed for the management of patients with cSDH treated with ASA. Guidelines for these patients exist in only 24.3% of the institutes. Most neurosurgeons discontinue ASA treatment for at least 7 days in the perioperative period of surgical evacuation of cSDH, even though recent studies show that early ASA resumption might be safe. Thrombosis prophylaxis is administered by only 60%, even though patients with cSDH are at high risk of developing thromboembolic complications. Better evidence and guidelines are warranted because the incidence of patients with cSDH under the treatment of ASA is increasing. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Estimation of internal radiation dose to the adult Asian population from the dietary intakes of two long-lived radionuclides

    International Nuclear Information System (INIS)

    Iyengar, G.V.; Kawamura, H.; Dang, H.S.; Parr, R.M.; Wang, J.W.; Akhter, Perveen; Cho, S.Y.; Natera, E.; Miah, F.K.; Nguyen, M.S.

    2004-01-01

    Daily dietary intakes of two naturally occurring long-lived radionuclides, 232 Th and 238 U, were estimated for the adult population living in a number of Asian countries, using highly sensitive analytical methods such as instrumental and radiochemical neutron activation analysis (INAA and RNAA), and inductively coupled plasma mass spectrometry (ICP-MS). The Asian countries that participated in the study were Bangladesh (BGD), China (CPR), India (IND), Japan (JPN), Pakistan (PAK), Philippines (PHI), Republic of Korea (ROK) and Vietnam (VIE). Altogether, these countries represent more than 50% of the world population. The median daily intakes of 232 Th ranged between 0.6 and 14.4 mBq, the lowest being for Philippines and the highest for Bangladesh, and daily intakes of 238 U ranged between 6.7 and 62.5 mBq, lowest and the highest being for India and China, respectively. The Asian median intakes were obtained as 4.2 mBq for 232 Th and 12.7 mBq for 238 U. Although the Asian intakes were lower than intakes of 12.3 mBq (3.0 μg) 232 Th and 23.6 mBq (1.9 μg) 238 U proposed by the International Commission on Radiological Protection (ICRP) for the ICRP Reference Man, they were comparable to the global intake values of 4.6 mBq 232 Th and 15.6 mBq 238 U proposed by the United Nation Scientific Commission on Effects of Radiation (UNSCEAR). The annual committed effective doses to Asian population from the dietary intake of 232 Th and 238 U were calculated to be 0.34 and 0.20 μSv, respectively, which are three orders of magnitude lower than the global average annual radiation dose of 2400 μSv to man from the natural radiation sources as proposed by UNSCEAR

  15. Results of study of Sr-90 and Cs-137 content in organism and effective doses of internal and external irradiation of Ukrainian population residing in different regions

    International Nuclear Information System (INIS)

    Kalmykov, L.; Gur, E.

    1996-01-01

    The authors have studied effective doses of internal and external radiation for 1992-1994 in the residents of Chernigov and Kharkov Regions of Ukraine, i.e. those who live in the zone of strict radioecologic control and in relatively ''clean'' zones, respectively. In 95% of the investigated residents of Chernigov Region Cs-137 activity in the organism was lower than 1500 Bq, maximum amount being 11 kBq. Conditioned Cs-137 effective dose of internal radiation did not exceed 250 micro Sv per year, in 96% of the investigated subjects it was less than 30 micro Sv per year. Mean amount of this radionuclide in the organisms of both adults and children aged 3-6 years residing in Kharkov Region was 90 and 6 Bq respectively, dose being 2 and 0.4 micro Sv per year. Sr-90 amount in the bone tissue decreases with the age and for the residents of Chernigov region it was 7-23 Bq/kg of bone, for the adult residents of Kharkov region it was about 3 Bq/kg of bone. Mean effective dose of internal radiation due to Sr-90 incorporation for the residents of both Kharkov and Chernigov Regions was 0.7 and 1.9 micro Sv per year. Effective dose of external radiation for the residents of Kharkov Region has not changed since the Chernobyl accident. Total effective dose of external and internal radiation in various professional groups for the residents of Chernigov region increased by 80 micro Sv per year which makes up 14% of mean population dose in Ukraine. (author). 11 refs, 5 tabs

  16. Spatial structure of food contamination with 137Cs and estimation of long-term internal dose loads on population of Belarus

    International Nuclear Information System (INIS)

    Krivoruchko, K.

    1997-01-01

    An analysis of 53,207 records of 137 Cs contents in 83 types of food products obtained in 1993 in Belarus was carried out. Internal exposure by eight selected food components has been estimated. To map the non-uniformly distributed data, different types of geostatical approaches are used. The results of spatial analysis of long term internal dose loads on populations under high radiation risk could be used in decision making. (author)

  17. Effect of Gold Nanoparticles on Prostate Dose Distribution under Ir-192 Internal and 18 MV External Radiotherapy Procedures Using Gel Dosimetry and Monte Carlo Method

    Directory of Open Access Journals (Sweden)

    Khosravi H.

    2015-03-01

    Full Text Available Background: Gel polymers are considered as new dosimeters for determining radiotherapy dose distribution in three dimensions. Objective: The ability of a new formulation of MAGIC-f polymer gel was assessed by experimental measurement and Monte Carlo (MC method for studying the effect of gold nanoparticles (GNPs in prostate dose distributions under the internal Ir-192 and external 18MV radiotherapy practices. Method: A Plexiglas phantom was made representing human pelvis. The GNP shaving 15 nm in diameter and 0.1 mM concentration were synthesized using chemical reduction method. Then, a new formulation of MAGIC-f gel was synthesized. The fabricated gel was poured in the tubes located at the prostate (with and without the GNPs and bladder locations of the phantom. The phantom was irradiated to an Ir-192 source and 18 MV beam of a Varian linac separately based on common radiotherapy procedures used for prostate cancer. After 24 hours, the irradiated gels were read using a Siemens 1.5 Tesla MRI scanner. The absolute doses at the reference points and isodose curves resulted from the experimental measurement of the gels and MC simulations following the internal and external radiotherapy practices were compared. Results: The mean absorbed doses measured with the gel in the presence of the GNPs in prostate were 15% and 8 % higher than the corresponding values without the GNPs under the internal and external radiation therapies, respectively. MC simulations also indicated a dose increase of 14 % and 7 % due to presence of the GNPs, for the same experimental internal and external radiotherapy practices, respectively. Conclusion: There was a good agreement between the dose enhancement factors (DEFs estimated with MC simulations and experiment gel measurements due to the GNPs. The results indicated that the polymer gel dosimetry method as developed and used in this study, can be recommended as a reliable method for investigating the DEF of GNPs in internal

  18. Effect of Gold Nanoparticles on Prostate Dose Distribution under Ir-192 Internal and 18 MV External Radiotherapy Procedures Using Gel Dosimetry and Monte Carlo Method.

    Science.gov (United States)

    Khosravi, H; Hashemi, B; Mahdavi, S R; Hejazi, P

    2015-03-01

    Gel polymers are considered as new dosimeters for determining radiotherapy dose distribution in three dimensions. The ability of a new formulation of MAGIC-f polymer gel was assessed by experimental measurement and Monte Carlo (MC) method for studying the effect of gold nanoparticles (GNPs) in prostate dose distributions under the internal Ir-192 and external 18MV radiotherapy practices. A Plexiglas phantom was made representing human pelvis. The GNP shaving 15 nm in diameter and 0.1 mM concentration were synthesized using chemical reduction method. Then, a new formulation of MAGIC-f gel was synthesized. The fabricated gel was poured in the tubes located at the prostate (with and without the GNPs) and bladder locations of the phantom. The phantom was irradiated to an Ir-192 source and 18 MV beam of a Varian linac separately based on common radiotherapy procedures used for prostate cancer. After 24 hours, the irradiated gels were read using a Siemens 1.5 Tesla MRI scanner. The absolute doses at the reference points and isodose curves resulted from the experimental measurement of the gels and MC simulations following the internal and external radiotherapy practices were compared. The mean absorbed doses measured with the gel in the presence of the GNPs in prostate were 15% and 8 % higher than the corresponding values without the GNPs under the internal and external radiation therapies, respectively. MC simulations also indicated a dose increase of 14 % and 7 % due to presence of the GNPs, for the same experimental internal and external radiotherapy practices, respectively. There was a good agreement between the dose enhancement factors (DEFs) estimated with MC simulations and experiment gel measurements due to the GNPs. The results indicated that the polymer gel dosimetry method as developed and used in this study, can be recommended as a reliable method for investigating the DEF of GNPs in internal and external radiotherapy practices.

  19. Radiation dose to the patient in radionuclide studies

    International Nuclear Information System (INIS)

    Roedler, H.D.

    1981-01-01

    In medical radionuclide studies, the radiation risk has to be considered in addition to the general risk of administering a pharmaceutical. As radiation exposure is an essential factor in radiation risk estimation, some aspects of internal dose calculation, including radiation risk assessments, are treated. The formalism of current internal dose calculation is presented. The input data, especially the residence time and the absorbed dose per transformation, their origin and accuracy are discussed. Results of internal dose calculations for the ten most frequently used radionuclide studies are presented as somatically effective dose equivalents. The accuracy of internal dose calculation is treated in detail by considering the biokinetics of the radiopharmaceutical, the phantoms used for dose calculations, the absorbed dose per transformation, the administered activity, and the transfer of the dose, calculated for a phantom, to the patient. The internal dose calculated for a reference phantom may be assumed to be in accordance with the actual patient dose within a range described by a factor of about two to three. Finally, risk estimates for nuclear medicine procedures are quantified, being generally of sixth order. The radiation risk from the radioiodine test is comparably higher, but probably lower than calculated according to the UNSCEAR risk coefficients. However, further studies are needed to confirm these preliminary results and to improve the quantification of the radiation risk from the medical use of radionuclides. (author)

  20. Effectiveness of two different doses of rituximab for the treatment of rheumatoid arthritis in an international cohort

    DEFF Research Database (Denmark)

    Chatzidionysiou, Katerina; Lie, Elisabeth; Nasonov, Evgeny

    2016-01-01

    months. DAS28 reductions at 6 months were comparable in the 2 dose regimens [mean DeltaDAS28 ± SD -2.0 ± 1.3 (high dose) vs. -1.7 ± 1.4 (low dose), p = 0.23 adjusted for baseline differences]. Similar percentages of patients achieved EULAR good response in the two dose groups, 18.4 % vs. 17...

  1. Effects of internal and external scatter on the build-up characteristics of Monte Carlo calculated absorbed dose for electron irradiation

    International Nuclear Information System (INIS)

    Lin, H.; Wu, DS.; Wu, AD.

    2005-01-01

    The effects of internal and external scatter on surface, build-up and depth dose characteristics simulated by Monte Carlo code EGSnrc for varying field size and SSD for a 10 MeV monoenergetic electron beam with and without an accelerator model are extensively studied in this paper. In particular, sub-millimetre surface PDD was investigated. The percentage depth doses affected significantly by the external scatter show a larger build-up dose. A forward shifted Dmax depth and a sharper fall-off region compared to PDDs with only internal scatter considered. The surface dose with both internal and external scatter shows a marked decrease at 110 cm SSD, and then slight further changes with the increasing SSD since few external scattered particles from accelerator model can reach the phantom for large SSDs. The sharp PDD increase for the 5 cm x 5 cm field compared to other fields seen when only internal scatter is considered is significantly less when external scatter is also present. The effect of external scatter on surface PDD is more pronounced for large fields than small fields (5 cm x 5 cm field)

  2. Assessment of the current internal dose due to 137Cs and 90Sr for people living within the Semipalatinsk Test Site, Kazakhstan.

    Science.gov (United States)

    Semiochkina, N; Voigt, G; Mukusheva, M; Bruk, G; Travnikova, I; Strand, P

    2004-02-01

    The Semipalatinsk Test Site in Kazakhstan was one of the major sites used by the USSR for testing nuclear weapons for more than 40 y. Since the early 1990's, responsibility for the site has passed to the Kazakh authorities. There has been a gradual re-establishment of agricultural use such as horse and sheep farming. Therefore, it has become important to evaluate the current and future risk to people living on and using the contaminated area. Internal dose assessment is one of the main components of the total dose when deriving risk factors for population living within the test site. Internal doses based on food monitoring and whole body measurements were calculated for adults and are in the range of 13-500 microSv y(-1) due to radiocesium and radiostrontium.

  3. Estimation of internal radiation dose to the adult Asian population from the dietary intakes of two long-lived radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Iyengar, G.V. E-mail: v.iyengar@iaea.org; Kawamura, H.; Dang, H.S.; Parr, R.M.; Wang, J.W.; Akhter, Perveen; Cho, S.Y.; Natera, E.; Miah, F.K.; Nguyen, M.S

    2004-07-01

    Daily dietary intakes of two naturally occurring long-lived radionuclides, {sup 232}Th and {sup 238}U, were estimated for the adult population living in a number of Asian countries, using highly sensitive analytical methods such as instrumental and radiochemical neutron activation analysis (INAA and RNAA), and inductively coupled plasma mass spectrometry (ICP-MS). The Asian countries that participated in the study were Bangladesh (BGD), China (CPR), India (IND), Japan (JPN), Pakistan (PAK), Philippines (PHI), Republic of Korea (ROK) and Vietnam (VIE). Altogether, these countries represent more than 50% of the world population. The median daily intakes of {sup 232}Th ranged between 0.6 and 14.4 mBq, the lowest being for Philippines and the highest for Bangladesh, and daily intakes of {sup 238}U ranged between 6.7 and 62.5 mBq, lowest and the highest being for India and China, respectively. The Asian median intakes were obtained as 4.2 mBq for {sup 232}Th and 12.7 mBq for {sup 238}U. Although the Asian intakes were lower than intakes of 12.3 mBq (3.0 {mu}g) {sup 232}Th and 23.6 mBq (1.9 {mu}g) {sup 238}U proposed by the International Commission on Radiological Protection (ICRP) for the ICRP Reference Man, they were comparable to the global intake values of 4.6 mBq {sup 232}Th and 15.6 mBq {sup 238}U proposed by the United Nation Scientific Commission on Effects of Radiation (UNSCEAR). The annual committed effective doses to Asian population from the dietary intake of {sup 232}Th and {sup 238}U were calculated to be 0.34 and 0.20 {mu}Sv, respectively, which are three orders of magnitude lower than the global average annual radiation dose of 2400 {mu}Sv to man from the natural radiation sources as proposed by UNSCEAR.

  4. Development and application of a tomographic model from CT images for calculating internal dose to a pregnant woman

    International Nuclear Information System (INIS)

    Shi Chengyu

    2004-01-01

    Assessment of radiation dose and possible risk to a pregnant woman and her fetus is an important task in radiation protection. Although stylized models for male and female patients of different ages have been developed, tomographic models for pregnant women have not been developed to date. This dissertation presents an effort to construct a partial-body model of a pregnant woman from a set of CT images. The patient was 30-weeks pregnant, and the CT scan covered the portion of the body from above liver to below pubic symphysis in 70 slices, each 7 mm thick. The image resolution was 512x512 pixels in a 48 cmx48 cm field. The images were carefully segmented to identify 34 organs and tissues. It has been found that the masses are different from the Reference Woman. The characteristics of the resulting model are discussed and compared with one existing stylized mathematical model for pregnant women. Based on this tomographic model, a Monte Carlo code, EGS4-VLSI, was used to derive specific absorbed fractions. Monoenergetic and isotropic photon and electron emitters distributed in different source organs were assumed and the energies ranged from 10 keV to 4 MeV for photons and from 100 keV to 4 MeV for electrons. The results for high energy (>50 keV) photons showed general agreement with previous studies, however, the results for lower energy (<50 keV) photons showed differences of up to several hundred percent for some source and target organs. For electron results, several tens of percent differences were found. Those differences can be explained by mass differences and the relative geometry differences between source and target organs. In summary, the stylized models for pregnant women are satisfactory for a very large size patient for most of the photon energies (between 50 keV and 4 MeV). However, a tomographic model has to be used to obtain acceptable dose assessments for electrons. The newly calculated SAF data set can provide the nuclear medicine dosimetry field

  5. Analyse of the international recommendations on the calculation of absorbed dose in the biota; Analise das recomendacoes internacionais sobre calculo de dose absorvida na biota

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Wagner de S.; Py Junior, Delcy de A., E-mail: wspereira@inb.gov.b, E-mail: delcy@inb.gov.b [Industrias Nucleares do Brasil (UTM/INB), Pocos de Caldas, MG (Brazil). Unidade de Tratamento de Minerios; Universidade Federal Fluminense (LARARA/UFF), Niteroi, RJ (Brazil). Lab. de Radiobiologia e Radiometria; Kelecom, Alphonse [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Programa de Pos-Graduacao em Ciencia Ambiental

    2011-10-26

    This paper evaluates the recommendations of ICRP which has as objective the environmental radioprotection. It was analysed the recommendations 26, 60, 91, 103 and 108 of the ICRP. The ICRP-103 defined the concept o