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Sample records for air kerma standardization

  1. Air-kerma determination using a variable-volume cavity ionization chamber standard.

    Science.gov (United States)

    Burns, D T; Kessler, C; Roger, P

    2007-12-01

    A graphite-walled cavity ionization chamber of modular design and variable volume has been used to determine the air-kerma rate in the reference 60Co field at the BIPM. The chamber can be configured in five sizes. High-accuracy mechanical measurements of the volume of the air cavity were made for each configuration using a co-ordinate measuring machine. Ionization current measurements were made for each configuration and corrected for the effects of ion recombination and diffusion, stem scatter and chamber orientation. Monte Carlo calculations of cavity dose were made to evaluate the correction factors kwall and kan. A reproducibility of the ionization current per mass of 1.5 parts in 10(4) was achieved on the repeated assembly of each configuration. The results show an air-kerma rate determination that increases with volume, the total change being around 8 parts in 10(4). When analysed differentially, the air-kerma rate relative to the BIPM standard is Kdiff/KBIPM = 1.0026(6). A detailed uncertainty budget is presented. Possible reasons for the observed behaviour are discussed that might have consequences for all existing standards for air-kerma.

  2. Air kerma standardization for diagnostic radiology, and requirements proposal for calibration laboratories

    International Nuclear Information System (INIS)

    The demand for calibration services and quality control in diagnostic radiology has grown in the country since the publication of the governmental regulation 453, issued by the Ministry of Health in 1998. At that time, to produce results facing the new legislation, many laboratories used different standards and radiation qualities, some of which could be inadequate. The international standards neither supplied consistent radiation qualities and standardization for the different types of equipment available. This situation changed with the publication of the new edition of the IEC 61267 standard, published in 2005. A metrology network was created, but it is not yet accredited by the accreditation organism of the country, INMETRO. The objective of this work was to implement the standardization of the air kerma for the un attenuated qualities (RQR) of IEC 61267, and to develop a requirement proposal for instruments calibration laboratories. Results of interlaboratory comparisons demonstrate that the quantity is standardized and internationally traceable. A laboratory requirement proposal was finalized and it shall be submitted to INMETRO to be used as auxiliary normative document in laboratory accreditation. (author)

  3. Comparison of the standards of air kerma of the OMH and the BIPM for 60Co gamma radiation

    International Nuclear Information System (INIS)

    A direct comparison between the standards for air kerma of the Orszagos Meresugyi Hivatal (OMH) and of the Bureau International des Poids et Mesures (BIPM) has been carried out in the 60Co radiation beams of the BIPM. The result, expressed as a ratio of the OMH and the BIPM standards for air kerma, indicates a relative difference of 10.9 x 10-3 with a combined standard uncertainty of 2.2 x 10-3. This new result agrees at the level of 0.4 x 10-3 with the earlier direct comparisons performed in 1986 and 1994, as modified in 2001 by the application of wall and axial non-uniformity correction factors, calculated for the OMH standards using the Monte Carlo method. (authors)

  4. Air kerma standardization for diagnostic radiology, and requirements proposal for calibration laboratories; Padronizacao da grandeza Kerma no ar para radiodiagnostico e proposta de requisitos para laboratorios de calibracao

    Energy Technology Data Exchange (ETDEWEB)

    Ramos, Manoel Mattos Oliveira

    2009-07-01

    The demand for calibration services and quality control in diagnostic radiology has grown in the country since the publication of the governmental regulation 453, issued by the Ministry of Health in 1998. At that time, to produce results facing the new legislation, many laboratories used different standards and radiation qualities, some of which could be inadequate. The international standards neither supplied consistent radiation qualities and standardization for the different types of equipment available. This situation changed with the publication of the new edition of the IEC 61267 standard, published in 2005. A metrology network was created, but it is not yet accredited by the accreditation organism of the country, INMETRO. The objective of this work was to implement the standardization of the air kerma for the un attenuated qualities (RQR) of IEC 61267, and to develop a requirement proposal for instruments calibration laboratories. Results of interlaboratory comparisons demonstrate that the quantity is standardized and internationally traceable. A laboratory requirement proposal was finalized and it shall be submitted to INMETRO to be used as auxiliary normative document in laboratory accreditation. (author)

  5. Determination of air kerma standard of high dose rate {sup 192}Ir brachytherapy source; Determinacao da taxa de kerma no ar de referencia para {sup 192}Ir de alta taxa de dose para braquiterapia

    Energy Technology Data Exchange (ETDEWEB)

    Pires, E.J.; Alves, C.F.E.; Leite, S.P.; Magalhaes, L.A.G.; David, M.G.; Almeida, C.E. de, E-mail: cfealves@gmail.com [Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, RJ (Brazil). Lab. de Ciencias Radiologicas; Di Prinzio, R. [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2015-07-01

    This paper presents the methodology developed by the Laboratorio de Ciencias Radiologicas and presently in use for determining of the air kerma standard of {sup 192}Ir high dose rate sources to calibrate well-type chambers. Uncertainty analysis involving the measurements procedure are presented. (author)

  6. Study and determination of the national dosimetric standards in terms of air kerma for X-rays radiation fields of low and medium-energies; Etude et realisation des references dosimetriques nationales en termes de kerma dans l'air pour les faisceaux de rayons X de basses et moyennes energies

    Energy Technology Data Exchange (ETDEWEB)

    Ksouri, W

    2008-12-15

    Progress in radiation protection and radiotherapy, and the increased needs in terms of accuracy lead national metrology institutes to improve the standard. For ionizing radiation, the standard is defined by an absolute instrument used for air kerma rate measurement. The aim of the thesis is to establish standards, in terms of air kerma for X-rays beams of low and medium-energies. This work enables to complement the standard beam range of the Laboratoire National Henri Becquerel (LNHB). Two free-air chambers have been developed, WK06 for medium-energy and WK07 for low-energy. The air-kerma rate is corrected by several correction factors. Some are determined experimentally; and the others by using Monte Carlo simulations. The uncertainty budget of the air-kerma rate at one standard deviation has been established. These dosimetric standards were compared with those of counterparts' laboratories and are consistent in terms of degree of equivalence. (author)

  7. Comparison BIPM.RI(I)-K8 of high dose-rate Ir-192 brachytherapy standards for reference air kerma rate of the VSL and the BIPM

    DEFF Research Database (Denmark)

    Alvarez, J.T.; De Pooter, J.A.; Andersen, Claus E.;

    2014-01-01

    An indirect comparison of the standards for reference air kerma rate for 192Ir high dose rate brachytherapy sources of the Dutch Metrology Institute (VSL), The Netherlands, and of the Bureau International des Poids et Mesures (BIPM) was carried out at the VSL in November 2009. The comparison resu...

  8. Key comparison BIPM.RI(I)-K1 of the air-kerma standards of the NIM, China and the BIPM in 60Co gamma radiation

    Science.gov (United States)

    Kessler, C.; Burns, D.; Wang, K.; Fan, Y.; Jin, S.; Yang, X.

    2016-01-01

    An indirect comparison of the standards for air kerma of the National Institute of Metrology (NIM), China and of the Bureau International des Poids et Mesures (BIPM) was carried out in the 60Co radiation beam of the BIPM in November 2015. The comparison result, evaluated as a ratio of the NIM and the BIPM standards for air kerma, is 0.9997 with a combined standard uncertainty of 2.7 × 10-3. The results are analysed and presented in terms of degrees of equivalence for entry in the BIPM key comparison database. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  9. Key comparison BIPM.RI(I)-K5 of the air kerma standards of the NIM, China, and the BIPM in 137Cs gamma radiation

    Science.gov (United States)

    Kessler, C.; Burns, D. T.; Li, D.; Wang, P.

    2015-01-01

    A direct comparison of the standards for air kerma of the National Institute of Metrology (NIM), Beijing, China, and of the Bureau International des Poids et Mesures (BIPM) was carried out in the 137Cs radiation beam of the BIPM in September 2014. The comparison result, evaluated as a ratio of the NIM and the BIPM standards for air kerma, is 0.9967 with a combined standard uncertainty of 2.1 × 10-3. The results are analysed and presented in terms of degrees of equivalence for entry in the BIPM key comparison database. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  10. Comparison of the air kerma standards of the IAEA and the BIPM in mammography x-rays

    Science.gov (United States)

    Kessler, C.; Burns, D. T.; Czap, L.; Csete, I.; Gomola, I.

    2013-01-01

    The Dosimetry Laboratory of the International Atomic Energy Agency (IAEA), Seibersdorf, Austria, calibrates reference standards in mammography x-ray beams for IAEA/WHO SSDL Network members (more than 80 laboratories worldwide). As a signatory of the Mutual Recognition Arrangement (CIPM MRA), the IAEA laboratory maintains a Quality Management System (QMS) complying with ISO 17025 and requires updated 'supporting evidence' for its dosimetry calibration and measurement capabilities (CMC), first published in Appendix C of the CIPM MRA key comparison database in 2007. For this purpose, an indirect comparison has been made between the air kerma standards of the IAEA and the Bureau International des Poids et Mesures (BIPM) in the mammography x-ray range from 25 kV to 35 kV, using as transfer instruments two thin-window parallel-plate ionization chambers belonging to the IAEA. The IAEA and BIPM standards for mammography x-rays are shown to be in agreement within the standard uncertainty of the comparison of 5.5 parts in 103. This agreement can be used to support the calibration and measurements capabilities of the IAEA listed in Appendix C of the key comparison database. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  11. Comparisons of the standards for air kerma of the PTB and the BIPM for {sup 60}Co and {sup 137}Cs gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Allisy-Roberts, P.J.; Burns, D.T. [Bureau International des Poids et Mesures (BIPM), 92 - Sevres (France); Buermann, L.; Kramer, H.M. [Physikalisch-Technische Bundesanstalt, Braunschweig (Germany)

    2005-11-15

    Direct comparisons of the standards for air kerma of the Physikalisch-Technische Bundesanstalt (PTB, Germany) and of the Bureau International des Poids et Mesures (BIPM) were carried out in the {sup 60}Co and {sup 137} Cs radiation beams of the BIPM in 2000. The results, expressed as ratios of the PTB and the BIPM standards for air kerma, indicate a relative difference in {sup 60}Co of 9.9 x 10{sup -3} with a combined standard uncertainty of 1.8 x 10{sup -3}, and in {sup 137}Cs of 6.4 x 10{sup -3} with a combined standard uncertainty of 2.8 x 10{sup -3}. The earlier comparisons in {sup 60}Co {gamma} rays made in 1971 (direct) and 1989 (indirect) resulted in an agreement of the two standards within 2 x 10{sup -3}. The differences obtained now are due to the application of new correction factors for wall effects and point source non-uniformity of the beam, k{sub wall} and k{sub pn}, for the PTB standards, which were calculated using Monte Carlo methods. (authors)

  12. KEY COMPARISON Comparison of the standards of air kerma of the ENEA-INMRI and the BIPM for 137Cs gamma rays

    Science.gov (United States)

    Allisy-Roberts, P. J.; Kessler, C.; Toni, M.; Bovi, M.

    2010-01-01

    A comparison of the standards of air kerma of the Istituto Nazionale di Metrologia delle Radiazioni Ionizzanti of the Ente per le Nuove Tecnologie, l'Energia e l'Ambiente, Italy (ENEA-INMRI) and of the Bureau International des Poids et Mesures (BIPM) was carried out in 137Cs radiation in 1998. The comparison result, updated for changes in the standards in 2003 and 2009, is 0.9927 (0.0067) and demonstrates that the ENEA-INMRI and BIPM standards are in agreement within the uncertainties. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI Section I, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

  13. Key comparison BIPM.RI(I)-K7 of the air-kerma standards of the CMI, Czech Republic and the BIPM in mammography x-rays

    Science.gov (United States)

    Kessler, C.; Burns, D.; Roger, P.; Sochor, V.

    2016-01-01

    A first key comparison has been made between the air-kerma standards of the CMI, Czech Republic and the BIPM in mammography x-ray beams. The results show the standards to be in agreement at the level of the standard uncertainty for the comparison of 3.5 parts in 103. The results for an indirect comparison made at the same time are consistent with the direct results at the level of 1 part in 103. The results are analysed and presented in terms of degrees of equivalence, suitable for entry in the BIPM key comparison database. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  14. Construction of a laboratory for the implantation of primary standardization of the magnitude kerma in the air for the X-ray beams used in mammography; Construcao de um laboratorio para a implantacao da padronizacao primaria da grandeza kerma no ar para os feixes de raios X empregados em mamografia

    Energy Technology Data Exchange (ETDEWEB)

    Cardozo, W.L.; Magalhes, L.A.A.M.F.; Peixoto, J.G.P., E-mail: wagnerlc@ird.gov.b [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil). Lab. Nacional de Metrologia das Radiacoes Ionizantes (LNMRI)

    2009-07-01

    Aiming to diminish the uncertainty in each phase of the metrological chain, and the uncertainty in dosimetry processed at the X-ray beam applied in the mammography, is necessary that the LNMRI/IRD to develop a reference primary standard for the absolute form to the magnitude kerma in the air

  15. Calculation of the correction factors for the primary standard of kerma in the air at the LNMRI-IRD, Rio de Janeiro, Brazil; Calculo de fatores de correcao para o padrao primario em kerma no ar do LNMRI-IRD, Rio de Janeiro, Brasil

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Cosme Norival Mello da, E-mail: cosme@ird.gov.b [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil). Lab. Nacional de Metrologia das Radiacoes Ionizantes (LNMRI)

    2009-07-01

    In order to determine the primary standardization in terms of kerma in the air, a graphite ionization chamber is used for calculation some correction factors. A program was elaborated, using the Monte Carlo Penelope for simulate the CC01-110 at the LNMRI/IRD, Rio de Janeiro, Brazil

  16. Evaluation of entrance surface air kerma from exposure index in computed radiography

    Science.gov (United States)

    Costa, A. M.; Pelegrino, M. S.

    2014-11-01

    The aim of this study was to establish an indirect method to calculate the values of entrance surface air kerma in patients undergoing diagnostic examinations in X-ray systems with computed radiography based on the exposure index. The entrance surface air kerma values were compared with values obtained also indirectly based on measurements of X-ray tube output. The mean±standard deviation (1σ) and third quartile for entrance surface air kerma calculated from the exposure index were 2.1±1.0 mGy and 3.0 mGy, respectively. For entrance surface air kerma based on measurements of the X-ray tube output, the mean±standard deviation (1σ) and third quartile were respectively 3.1±1.9 mGy and 5.5 mGy. The observed values of entrance surface air kerma are smaller than the reference level adopted in Brazil (10 mGy). The results obtained with both methods were similar when taking into account the estimated uncertainties in the determination of air kerma values, although the reproducibility of the determinations based on the exposure index is better.

  17. Comparison between absorbed dose to water standards established by water calorimetry at the LNE-LNHB and by application of international air-kerma based protocols for kilovoltage medium energy x-rays.

    Science.gov (United States)

    Perichon, N; Rapp, B; Denoziere, M; Daures, J; Ostrowsky, A; Bordy, J-M

    2013-05-01

    Nowadays, the absorbed dose to water for kilovoltage x-ray beams is determined from standards in terms of air-kerma by application of international dosimetry protocols. New standards in terms of absorbed dose to water has just been established for these beams at the LNE-LNHB, using water calorimetry, at a depth of 2 cm in water in accordance with protocols. The aim of this study is to compare these new standards in terms of absorbed dose to water, to the dose values calculated from the application of four international protocols based on air-kerma standards (IAEA TRS-277, AAPM TG-61, IPEMB and NCS-10). The acceleration potentials of the six beams studied are between 80 and 300 kV with half-value layers between 3.01 mm of aluminum and 3.40 mm of copper. A difference between the two methods smaller than 2.1% was reported. The standard uncertainty of water calorimetry being below 0.8%, and the one associated with the values from protocols being around 2.5%, the results are in good agreement. The calibration coefficients of some ionization chambers in terms of absorbed dose to water, established by application of calorimetry and air-kerma based dosimetry protocols, were also compared. The best agreement with the calibration coefficients established by water calorimetry was found for those established with the AAPM TG-61 protocol.

  18. The air-kerma rate constant of 192Ir.

    Science.gov (United States)

    Ninković, M M; Raiĉevìć, J J

    1993-01-01

    The air-kerma rate constant gamma delta (and its precursors), as one of the basic radiation characteristics of 192Ir, was determined by many authors. Analysis of accessible data on this quantity led us to the conclusion that published data strongly disagree. That is the reason we calculated this quantity on the basis of our and many other authors' gamma-ray spectral data and the latest data for mass energy-transfer coefficients for air. In this way, a value was obtained for gamma delta of 30.0 +/- 0.9 a Gy m2 s-1 Bq-1 for an unshielded 192Ir source and 27.8 +/- 0.9 a Gy m2s -1Bq-1 for a standard packaged radioactive source taking into account attenuation of gamma rays in the platinum source wall. PMID:8416220

  19. SU-E-T-552: Monte Carlo Calculation of Correction Factors for a Free-Air Ionization Chamber in Support of a National Air-Kerma Standard for Electronic Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Mille, M; Bergstrom, P [National Institute of Standards and Technology, Gaithersburg, MD (United States)

    2015-06-15

    Purpose: To use Monte Carlo radiation transport methods to calculate correction factors for a free-air ionization chamber in support of a national air-kerma standard for low-energy, miniature x-ray sources used for electronic brachytherapy (eBx). Methods: The NIST is establishing a calibration service for well-type ionization chambers used to characterize the strength of eBx sources prior to clinical use. The calibration approach involves establishing the well-chamber’s response to an eBx source whose air-kerma rate at a 50 cm distance is determined through a primary measurement performed using the Lamperti free-air ionization chamber. However, the free-air chamber measurements of charge or current can only be related to the reference air-kerma standard after applying several corrections, some of which are best determined via Monte Carlo simulation. To this end, a detailed geometric model of the Lamperti chamber was developed in the EGSnrc code based on the engineering drawings of the instrument. The egs-fac user code in EGSnrc was then used to calculate energy-dependent correction factors which account for missing or undesired ionization arising from effects such as: (1) attenuation and scatter of the x-rays in air; (2) primary electrons escaping the charge collection region; (3) lack of charged particle equilibrium; (4) atomic fluorescence and bremsstrahlung radiation. Results: Energy-dependent correction factors were calculated assuming a monoenergetic point source with the photon energy ranging from 2 keV to 60 keV in 2 keV increments. Sufficient photon histories were simulated so that the Monte Carlo statistical uncertainty of the correction factors was less than 0.01%. The correction factors for a specific eBx source will be determined by integrating these tabulated results over its measured x-ray spectrum. Conclusion: The correction factors calculated in this work are important for establishing a national standard for eBx which will help ensure that dose

  20. SU-E-T-552: Monte Carlo Calculation of Correction Factors for a Free-Air Ionization Chamber in Support of a National Air-Kerma Standard for Electronic Brachytherapy

    International Nuclear Information System (INIS)

    Purpose: To use Monte Carlo radiation transport methods to calculate correction factors for a free-air ionization chamber in support of a national air-kerma standard for low-energy, miniature x-ray sources used for electronic brachytherapy (eBx). Methods: The NIST is establishing a calibration service for well-type ionization chambers used to characterize the strength of eBx sources prior to clinical use. The calibration approach involves establishing the well-chamber’s response to an eBx source whose air-kerma rate at a 50 cm distance is determined through a primary measurement performed using the Lamperti free-air ionization chamber. However, the free-air chamber measurements of charge or current can only be related to the reference air-kerma standard after applying several corrections, some of which are best determined via Monte Carlo simulation. To this end, a detailed geometric model of the Lamperti chamber was developed in the EGSnrc code based on the engineering drawings of the instrument. The egs-fac user code in EGSnrc was then used to calculate energy-dependent correction factors which account for missing or undesired ionization arising from effects such as: (1) attenuation and scatter of the x-rays in air; (2) primary electrons escaping the charge collection region; (3) lack of charged particle equilibrium; (4) atomic fluorescence and bremsstrahlung radiation. Results: Energy-dependent correction factors were calculated assuming a monoenergetic point source with the photon energy ranging from 2 keV to 60 keV in 2 keV increments. Sufficient photon histories were simulated so that the Monte Carlo statistical uncertainty of the correction factors was less than 0.01%. The correction factors for a specific eBx source will be determined by integrating these tabulated results over its measured x-ray spectrum. Conclusion: The correction factors calculated in this work are important for establishing a national standard for eBx which will help ensure that dose

  1. X-rays spectrum and air Kerma during a mammography study; Espectro de los rayos X y Kerma en aire durante un estudio mamografico

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez G, J. [Instituto Nacional de Estadistica Geografia e Informatica, Av. Heroes de Nacozari Sur 2301, Fracc. Jardines del Parque, 20276 Aguascalientes (Mexico); Hernandez V, R.; Hernandez D, V. M.; Vega C, H. R. [Unidad Academica de Estudios Nucleares, Universidad Autonoma de Zacatecas, Cipres 10, Fracc. La Penuela, 98068 Zacatecas (Mexico)], e-mail: fermineutron@yahoo.com

    2009-10-15

    In this calculation series was modeled the source of electrons, the target and the filter. Using thermoluminescent dosemeters of ZrO{sub 2}+PTFE the air Kerma was measured in five points located on a phantom made with acrylic and water when it was exposed to a X-rays beam produced by electrons of 24 KeV and 10 m A of current that produces a mammography. The air Kerma values at the entrance surface of the phantom were compared with values calculated by Monte Carlo methods. The air Kerma values measured indicate that approximately the five points receive the same air Kerma, what means that the beam is homogeneous, of the Monte Carlo calculations we find that the center receives a greater dose what implies that the beam is not uniform, the explanation of this fact is attributed to was used a simple model in the calculations, nevertheless, the air Kerma average measured at the entrance surface of the phantom was of 0.96 +{sub -} 0.03 m G, while the other obtained by the calculations was of 0.96 +{sub -} 0.06 mGy, to compare both do not exist significant differences. (author)

  2. Image quality and volume computed tomography air kerma index (Cvol) evaluation in Recife

    International Nuclear Information System (INIS)

    The Computed Tomography (CT) is an important diagnostic imaging method, widely used. However, in spite of all the advantages and technologic advances within the CT scanners, the tomographic procedures result in high absorbed doses to patients. The main objective of this work was to perform a dosimetric study of CT scanners located at Recife and to evaluate the image quality on CT examinations in these equipment. The volume CT air kerma index (CVOL) and air kerma length product (PKL,CT) were estimated. These values were calculated using normalized weighted air kerma indexes in CT standard dosimetry phantoms (nCW), supplied by ImPACT group for several CT scanners, and the scan parameters of routine head, routine chest and hi-resolution chest CT exams performed at 20 institutions. The irradiation parameters of 15 adult patients for each CT procedure were registered at six participating centres, at which the phantom from the American College of Radiology (ACR) CT accreditation protocol was used for the image quality measurements. For routine head exams, the CVOL values varied between 12 and 58 mGy (at the posterior fossa) and 15 to 58 mGy (at the cerebrum) and the PKL,CT, from 150 to 750 mGy·cm. The CVOL values for routine chest procedures varied from 3 to 26 mGy and the PKL,CT, between 120 and 460 mGy·cm. In relation to Hi-resolution chest exams, CVOL values were from 1.0 to 2.7 mGy and the PKL,CT values varied between 24 and 67 mGy·cm. The image quality evaluations results showed that almost all scanners presented at least one inadequacy. One of the equipment presented faults at 70% of the tests. With regard to the image noise, only two scanners presented acceptable results. From these results, it is possible to conclude that the volume CT air kerma index values are lower than the European reference levels. However, the image quality of these CT scanners does not attend the ACR requirements, suggesting the need to implement quality assurance programs at the

  3. X-rays spectrum and air Kerma during a mammography study

    International Nuclear Information System (INIS)

    In this calculation series was modeled the source of electrons, the target and the filter. Using thermoluminescent dosemeters of ZrO2+PTFE the air Kerma was measured in five points located on a phantom made with acrylic and water when it was exposed to a X-rays beam produced by electrons of 24 KeV and 10 m A of current that produces a mammography. The air Kerma values at the entrance surface of the phantom were compared with values calculated by Monte Carlo methods. The air Kerma values measured indicate that approximately the five points receive the same air Kerma, what means that the beam is homogeneous, of the Monte Carlo calculations we find that the center receives a greater dose what implies that the beam is not uniform, the explanation of this fact is attributed to was used a simple model in the calculations, nevertheless, the air Kerma average measured at the entrance surface of the phantom was of 0.96 +- 0.03 m G, while the other obtained by the calculations was of 0.96 +- 0.06 mGy, to compare both do not exist significant differences. (author)

  4. X-Rays spectrum and air kerma during a mammography study;Espectro de los rayos X y kerma en aire durante un estudio mamografico

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez G, J. [Instituto Nacional de Estadistica Geografia e Informatica, Direccion General de Innovacion y Tecnologia de Informacion, Av. Heroes de Nacozari Sur No. 2301, Fracc. Jardines del Parque, 20276 Aguascalientes (Mexico); Hernandez V, R.; Chacon R, A.; Vega C, H. R., E-mail: ramirezgonzalezjaime@yahoo.com.m [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Calle Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico)

    2009-10-15

    The X-rays spectrum produced in a mammography has been calculated by means of Monte Carlo methods. In this calculation series it is modeled the electrons source, the target and the filter. The spectra were calculated for an energy of the electrons of 28 keV and for targets of W, Mo and Rh. The calculations extended to analyze the effect that produces the filters inclusion in the spectra; the spectra of W-A1, Rh-Rh, Mo-Mo, Mo-Rh and Mo-Be were calculated this way. Using thermoluminescent dosemeters of ZrO{sub 2}+PTFE the air kerma was measured in five points located on a phantom made with acrylic and water when it is was exposed to a X-rays beam produced by electrons of 24 keV and 10 m A of current that it produces a mammography. The values of the air kerma on the entrance surface of the phantom were compared with the calculated values by means of Monte Carlo methods. The calculated spectra present a continuous component and another discreet and its form is similar to the reported spectra in the literature. The filters inclusion allows the elimination of the low energy photons that do not have utility in the obtaining of the mammography image and only they contribute to deposit a dose in the mamma. The values of the measured air kerma indicate that the five points receive the same air kerma approximately, what means that the beam is homogeneous, of the Monte Carlo calculations we find that the center receives a bigger dose which implies that the beam is not uniform, the explanation on this fact it is attributed to that a simple model was used in the calculations, nevertheless, the average of the air kerma measured on the entrance surface of the phantom was of 0.96 +- 0.03 m G, while the obtained by means of the calculations was of 0.96 +- 0.06 mGy, when comparing both significant differences do not exist. (Author)

  5. Air kerma to Hp(3) conversion coefficients for a new cylinder phantom for photon reference radiation qualities

    International Nuclear Information System (INIS)

    The International Organization for Standardization (ISO) has issued a standard series on photon reference radiation qualities (ISO 4037). In this series, no conversion coefficients are contained for the quantity personal dose equivalent at a 3 mm depth, Hp(3). In the past, for this quantity, a slab phantom was recommended as a calibration phantom; however, a cylinder phantom much better approximates the shape of a human head than a slab phantom. Therefore, in this work, the conversion coefficients from air kerma to Hp(3) for the cylinder phantom are supplied for X- and gamma radiation qualities defined in ISO 4037. (authors)

  6. Product estimate of air kerma-area and the air kerma in the input surface of the skin of pediatric patients undergoing chest X-ray

    International Nuclear Information System (INIS)

    The aim of this paper is to evaluate the entrance air kerma (Ka,e) and the product air kerma-area (Pka) for chest examinations performed with pediatric patients in a large public hospital of Recife. For this study 89 examinations of patient with ages from zero to 10 years old were evaluated. The results showed that the mean Ka,e values, for patients of 0-1 years old, 1-5 years old and 5-10 years old, were, respectively, 100 mGy, 120 mGy and 100 mGy. The Pka values for newborn patients range from 11,9 to 58,4 mGy.cm2, for patients with 1 to 5 years old range from 17 to 192 mGy.cm2, and from 30,4 to 136,2 mGy.cm2 for patients with ages from 5 to 10 years old. The differences in the Pka values are due the different dimensions of the radiation field. For the results its possible to conclude that the Pka values are high, in special for patients with ages from 1 to 5 years old, indicating that the collimation of the radiation field is not adequate. (author)

  7. Portable meter study of ionizing radiation Teletector in high rates of air kerma

    International Nuclear Information System (INIS)

    A set of portable meters of ionizing radiation high rates of air kerma (teletectors) commonly used in emergencies in Brazil and sent to the Calibration Laboratory of IPEN were under several tests and analyst is parameters for the detectors behavior were established. Applied tests were: energy dependence and primarily overload with the new irradiation system. Thus it was possible to determine the most common characteristic found in these equipment (quality control programs) and new calibration criteria were established following international recommendations. (author)

  8. Portable meter study of ionizing radiation Teletector in high rates of air kerma

    Energy Technology Data Exchange (ETDEWEB)

    Damatto, Willian Behling; Potiens, Maria da Penha A.; Vivolo, Vitor, E-mail: willbdamatto@gmail.com [Instituto de Pesquisas Energeticas e Nucleres (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    A set of portable meters of ionizing radiation high rates of air kerma (teletectors) commonly used in emergencies in Brazil and sent to the Calibration Laboratory of IPEN were under several tests and analyst is parameters for the detectors behavior were established. Applied tests were: energy dependence and primarily overload with the new irradiation system. Thus it was possible to determine the most common characteristic found in these equipment (quality control programs) and new calibration criteria were established following international recommendations. (author)

  9. APMP key comparison for the measurement of air kerma for 60Co (APMP.RI(I)-K1.1)

    Science.gov (United States)

    Webb, D. V.; Lee, J.-H.; Budiantari, C. T.; Laban, J.; Saito, N.; Srimanoroth, S.; Khaled, N. E.

    2016-01-01

    The results are reported for an APMP.R(I)-K1.1 comparison that extends the regional comparison of standards for air kerma APMP.R(I)-K1 to several laboratories unable to participate earlier. The comparison was conducted with the goal of supporting the relevant calibration and measurement capabilities (CMCs) planned for publication by the participant laboratories. The comparison was conducted by the pilot laboratory, the Australian Radiation Protection and Nuclear Safety (ARPANSA), Australia, supported by the Institute of Nuclear Energy Research (INER), Taiwan, in a modified ring-shaped arrangement from September 2009 to November 2010, in parallel with an APMP.R(I)-K4 comparison being piloted by the INER. The laboratories that took part in the comparison were the ARPANSA, the Centre of Technology of Radiation Safety and Metrology (PTKMR-BATAN), Indonesia, the Division of Radiation and Medical Devices (DMSC), Thailand, the INER, the National Centre for Radiation Science (NCRS), New Zealand, the National Institute for Standards (NIS), Egypt and the National Metrology Institute of Japan (NMIJ/AIST), Japan. The two primary laboratories, ARPANSA and NMIJ, were chosen as the linking laboratories. Three ionization chambers were used as transfer instruments to be calibrated in terms of air kerma in 60Co radiotherapy beams. The comparison result is based on the ratio between the air kerma calibration coefficients (NK) determined by the participants and the mean of the results of the linking laboratories. The mean comparison ratio was found to be within 0.5 % of the key comparison reference value KCRV. The largest deviation between any two comparison ratios for the three chambers in terms of air kerma was 2.0 %. An analysis of the participant uncertainty budgets enabled the calculation of degrees of equivalence (DoE) in terms of the deviations of the results and their associated uncertainties. As a result of this APMP comparison, the BIPM key comparison database (KCDB) should

  10. Calculated neutron air kerma strength conversion factors for a generically encapsulated Cf-252 brachytherapy source

    CERN Document Server

    Rivard, M J; D'Errico, F; Tsai, J S; Ulin, K; Engler, M J

    2002-01-01

    The sup 2 sup 5 sup 2 Cf neutron air kerma strength conversion factor (S sub K sub N /m sub C sub f) is a parameter needed to convert the radionuclide mass (mu g) provided by Oak Ridge National Laboratory into neutron air kerma strength required by modern clinical brachytherapy dosimetry formalisms indicated by Task Group No. 43 of the American Association of Physicists in Medicine (AAPM). The impact of currently used or proposed encapsulating materials for sup 2 sup 5 sup 2 Cf brachytherapy sources (Pt/Ir-10%, 316L stainless steel, nitinol, and Zircaloy-2) on S sub K sub N /m sub C sub f was calculated and results were fit to linear equations. Only for substantial encapsulation thicknesses, did S sub K sub N /m sub C sub f decrease, while the impact of source encapsulation composition is increasingly negligible as Z increases. These findings are explained on the basis of the non-relativistic kinematics governing the majority of sup 2 sup 5 sup 2 Cf neutron interactions. Neutron kerma and energy spectra resul...

  11. Integration of kerma-area product and cumulative air kerma determination into a skin dose tracking system for fluoroscopic imaging procedures

    Science.gov (United States)

    Vijayan, Sarath; Shankar, Alok; Rudin, Stephen; Bednarek, Daniel R.

    2016-03-01

    The skin dose tracking system (DTS) that we developed provides a color-coded mapping of the cumulative skin dose distribution on a 3D graphic of the patient during fluoroscopic procedures in real time. The DTS has now been modified to also calculate the kerma area product (KAP) and cumulative air kerma (CAK) for fluoroscopic interventions using data obtained in real-time from the digital bus on a Toshiba Infinix system. KAP is the integral of air kerma over the beam area and is typically measured with a large-area transmission ionization chamber incorporated into the collimator assembly. In this software, KAP is automatically determined for each x-ray pulse as the product of the air kerma/ mAs from a calibration file for the given kVp and beam filtration times the mAs per pulse times the length and width of the beam times a field nonuniformity correction factor. Field nonuniformity is primarily the result of the heel effect and the correction factor was determined from the beam profile measured using radio-chromic film. Dividing the KAP by the beam area at the interventional reference point provides the area averaged CAK. The KAP and CAK per x-ray pulse are summed after each pulse to obtain the total procedure values in real-time. The calculated KAP and CAK were compared to the values displayed by the fluoroscopy machine with excellent agreement. The DTS now is able to automatically calculate both KAP and CAK without the need for measurement by an add-on transmission ionization chamber.

  12. Product kerma in the air-area and radiation dose in dental radiodiagnosis

    International Nuclear Information System (INIS)

    The main purpose of patient dosimetry in diagnostic radiology is to determine dosimetric quantities for the establishment and use of reference levels and comparative risk assessment. In recent publications the use of the air kerma-area product, PKA, has been suggested in dental radiology, as this quantity is more closely related to risk. The aim of this study was to perform a preliminary survey of PKA and effective dose in different types of dental examinations. The future perspective is a large-scale survey for the establishment and use of diagnostic reference levels in dentistry in Brazil. (author)

  13. Air kerma and absorbed dose on the torso of a patient during a mammography study;Kerma en aire y dosis absorbida en el torso de una paciente durante un estudio mastografico

    Energy Technology Data Exchange (ETDEWEB)

    Hernadez O, M.; Duran M, H. A.; Pinedo S, A.; Gonzalez G, R.; Guerra M, J. A.; Salas L, M. A.; Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Calle Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico); Rivera M, T. [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Av. Legaria 694, 11500 Mexico D. F. (Mexico); Azorin N, J., E-mail: mar_h2o@hotmail.co [Universidad Autonoma Metropolitana, Unidad Iztapalapa, Av. San Rafael Atlixco 186, 09340 Mexico D. F. (Mexico)

    2009-10-15

    Two dosimetric magnitudes, due to the dispersed radiation, have been determined during a mammography study. The magnitudes that were determined are the kerma at the entrance of the torso and the absorbed dose by the torso. This determination was made in a paraffin phantom and with thermoluminescent dosemeters. One of the important parameters in the radiological protection of a patient to which is practiced a mammography is the value of the media glandular dose. However, during the taking of the X-ray a radiation portion that impacts on the mammary gland it is dispersed toward the patient's torso. In this work thermoluminescent dosemeters of ZrO{sub 2} has been used to determine the kerma at the entrance of the torso like the absorbed dose. The dosemeters was placed on the surface of the torso phantom while to the mamma phantom was made the mammography. As mamma phantom was used glucose serum to 5%. Of the obtained results we find that 3% of the air kerma at the entrance of the mamma it corresponds at the air kerma that receives the torso and 3.2% of the media glandular dose it is the absorbed dose of the same one. Another important result is the percentage value of the air kerma on the entrance of the thyroid area during a mammography, due to the dispersed radiation, it is 4% of the kerma at the entrance of the mamma. The air kerma at the entrance of the thyroid is of 0.41 +-0.07 mGy, 10% of this value corresponds to the absorbed dose by the thyroid. Therefore, it is observed that the media glandular dose and the air kerma at the entrance of the mamma they influence on the dispersed radiation toward the torso. Also, the superior part of the torso has less attenuation capacity to the dispersed radiation that those located in the inferior part. Therefore, the thyroid receives the major quantity of air kerma at the entrance. (Author)

  14. Product kerma in the air-area and radiation dose in dental radiodiagnosis; Produto kerma ar-area e dose efetiva em radiodiagnostico odontologico

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Alessandro Martins da, E-mail: amcosta@usp.br [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Filosofia, Ciencias e Letras. Dept. de Fisica

    2014-07-01

    The main purpose of patient dosimetry in diagnostic radiology is to determine dosimetric quantities for the establishment and use of reference levels and comparative risk assessment. In recent publications the use of the air kerma-area product, PKA, has been suggested in dental radiology, as this quantity is more closely related to risk. The aim of this study was to perform a preliminary survey of PKA and effective dose in different types of dental examinations. The future perspective is a large-scale survey for the establishment and use of diagnostic reference levels in dentistry in Brazil. (author)

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

    International Nuclear Information System (INIS)

    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 DPMMA(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)/Ka obtaining a value of 1.20 Sv Gy-1 with a uc= 3.66%, this being consistent with the published value in ISO-4037-3 of 1.20 Sv Gy-1 with a uc= 2%. (Author)

  16. Air-kerma evaluation at the maze entrance of HDR brachytherapy facilities

    International Nuclear Information System (INIS)

    In the absence of procedures for evaluating the design of brachytherapy (BT) facilities for radiation protection purposes, the methodology used for external beam radiotherapy facilities is often adapted. The purpose of this study is to adapt the NCRP 151 methodology for estimating the air-kerma rate at the door in BT facilities. Such methodology was checked against Monte Carlo (MC) techniques using the code Geant4. Five different facility designs were studied for 192Ir and 60Co HDR applications to account for several different bunker layouts. For the estimation of the lead thickness needed at the door, the use of transmission data for the real spectra at the door instead of the ones emitted by 192Ir and 60Co will reduce the lead thickness by a factor of five for 192Ir and ten for 60Co. This will significantly lighten the door and hence simplify construction and operating requirements for all bunkers. The adaptation proposed in this study to estimate the air-kerma rate at the door depends on the complexity of the maze: it provides good results for bunkers with a maze (i.e. similar to those used for linacs for which the NCRP 151 methodology was developed) but fails for less conventional designs. For those facilities, a specific Monte Carlo study is in order for reasons of safety and cost-effectiveness. (paper)

  17. Air kerma strength calibration of 0.6 cc Farmer chamber for 192Ir HDR source

    International Nuclear Information System (INIS)

    One of the methods adopted by hospitals for the calibration of the HDR 192Ir source, in terms of Air Kerma Strength (AKS) is to use 0.6cc chamber at short source to chamber distances for measuring the air kerma rate at the chamber position and then compute the AKS using the appropriate correction factors. However, the 0.6 cc Farmer type chambers purchased by the users for the calibration of the HDR 192Ir source, are not generally provided with an HDR 192Ir calibration factor. With the result, many hospitals that have purchased the Farmer type chamber for the calibration of 192Ir HDR sources, use the 60Co calibration factor for this purpose. The use of 60Co calibration factor for the 192Ir HDR source would unnecessarily increase the uncertainty of the measured AKS. Again, because of the low chamber sensitivity, hospitals often use, source to chamber distances as small as a few cm for calibrating the 192Ir HDR source. In the absence of a rigid source-chamber positioning system, this can lead to several percent errors in AKS determination. Also, hospitals often don't take into account corrections for the room scatter or the fluence non-uniformity across the chamber, which further increase the uncertainty of the measured AKS

  18. Kerma rate evaluation in the air in a room interventional cardiology; Avaliacao da taxa de Kerma no ar em uma sala de cardiologia intervencionista

    Energy Technology Data Exchange (ETDEWEB)

    Real, Jessica V.; Luz, Renata M. da, E-mail: jessica.real@pucrs.br, E-mail: renata.luz@pucrs.br [Hospital Sao Lucas (HSL/PUCRS), Porto Alegre, RS (Brazil); Fröhlich, Bruna D.; Silva, Ana Maria Marques da, E-mail: bruna.frohlich@acad.pucrs.br, E-mail: ana.marques@pucrs.br [Pontificia Universidade Catolica do Rio Grande do Sul (PUCRS), Porto Alegre, RS (Brazil)

    2014-07-01

    In recent years, the number of interventional cardiology procedures is increasing. However, due to the long time of fluoroscopy in these procedures, care teams can receive high doses of radiation. The radiation scattered by the patient is not uniform, and their assessment is of utmost importance. This study aimed to estimate and map the kerma rate in the air at the time of the gonads, in an interventional cardiology room, seeking to optimize the dose absorbed by individuals occupationally exposed to ionizing radiation. For data collection, the room was divided into quadrants of 1m{sup 2}, totaling 40 collection points. The simulator was positioned so that its entry surface was located in the interventional reference point. Were chosen the conditions that simulate angiography and angioplasty procedures performed in the service. The data were obtained for height of 1 meter, gonad region. The results obtained for kerma rates in air, in quadrants, show that higher measured values was in the vicinity of the X-ray tube. Has been found that the medical staff are more exposed, because of its location during the procedure, around the table. The law of the inverse square distance of the farthest points of the X-ray tube were verified.

  19. Image quality and volume computed tomography air kerma index (C{sub vol}) evaluation in Recife; Avaliacao da qualidade de imagem e do indice volumetrico de Kerma ar em tomografia computadorizada (C{sub vol}) em Recife

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, Marcos Ely Almeida

    2008-07-01

    The Computed Tomography (CT) is an important diagnostic imaging method, widely used. However, in spite of all the advantages and technologic advances within the CT scanners, the tomographic procedures result in high absorbed doses to patients. The main objective of this work was to perform a dosimetric study of CT scanners located at Recife and to evaluate the image quality on CT examinations in these equipment. The volume CT air kerma index (C{sub VOL}) and air kerma length product (P{sub KL,CT}) were estimated. These values were calculated using normalized weighted air kerma indexes in CT standard dosimetry phantoms ({sub n}C{sub W}), supplied by ImPACT group for several CT scanners, and the scan parameters of routine head, routine chest and hi-resolution chest CT exams performed at 20 institutions. The irradiation parameters of 15 adult patients for each CT procedure were registered at six participating centres, at which the phantom from the American College of Radiology (ACR) CT accreditation protocol was used for the image quality measurements. For routine head exams, the C{sub VOL} values varied between 12 and 58 mGy (at the posterior fossa) and 15 to 58 mGy (at the cerebrum) and the P{sub KL,CT}, from 150 to 750 mGy{center_dot}cm. The C{sub VOL} values for routine chest procedures varied from 3 to 26 mGy and the P{sub KL,CT}, between 120 and 460 mGy{center_dot}cm. In relation to Hi-resolution chest exams, C{sub VOL} values were from 1.0 to 2.7 mGy and the P{sub KL,CT} values varied between 24 and 67 mGy{center_dot}cm. The image quality evaluations results showed that almost all scanners presented at least one inadequacy. One of the equipment presented faults at 70% of the tests. With regard to the image noise, only two scanners presented acceptable results. From these results, it is possible to conclude that the volume CT air kerma index values are lower than the European reference levels. However, the image quality of these CT scanners does not attend the

  20. Conversion coefficients from air kerma to personal dose equivalent Hp(3) fir eye-lens dosimetry

    International Nuclear Information System (INIS)

    This work has been performed within the frame of the European Union ORAMED project (Optimization of Radiation protection for Medical staff). The main goal of the project is to improve standards of protection for medical staff for procedure resulting in potentially high exposures and to develop methodologies for better assessing and for reducing exposures to medical staff. The Work Package WP2 is involved in the development of practical eye lens dosimetry in interventional radiology. This study is complementary of the part of the ENEA report concerning the calculations with the MCNP code of the conversion factors related to the operational quantity Hp(3). A set of energy and angular dependent conversion coefficients Hp(3)/Kair in the new proposed square cylindrical phantom of ICRU tissue, have been calculated with the Monte-Carlo code PENELOPE. The Hp(3) values have been determined in terms of absorbed dose, according to the definition of this quantity, and also with the kerma approximation as formerly reported in ICRU reports. At low photon energy, up to 1 MeV, the two sets of conversion coefficients are consistent. Nevertheless, the differences increase at higher energy. This is mainly due to the lack of electronic equilibrium, especially for small angle incidences. The values of the conversion coefficients obtained with the code MCNP published by ENEA, agree with the kerma approximation calculations with PENELOPE. They are coherent with previous calculations in phantoms different in shape. But above 1 MeV, differences between conversion coefficient values calculated with the absorbed dose and with kerma approximation are significantly increasing, especially at low incidence angles. At those energies the electron transport has to be simulated. (author)

  1. Evaluation of conversion coefficients relating air-kerma to H*(10) using primary and transmitted x-ray spectra in the diagnostic radiology energy range.

    Science.gov (United States)

    Santos, J C; Mariano, L; Tomal, A; Costa, P R

    2016-03-01

    According to the International Commission on Radiation Units and Measurements (ICRU), the relationship between effective dose and incident air-kerma is complex and depends on the attenuation of x-rays in the body. Therefore, it is not practical to use this quantity for shielding design purposes. This correlation is adopted in practical situations by using conversion coefficients calculated using validated mathematical models by the ICRU. The ambient dose equivalent, H*(10), is a quantity adopted by the IAEA for monitoring external exposure. Dose constraint levels are established in terms of H*(10), while the radiation levels in radiometric surveys are calculated by means of the measurements of air-kerma with ion chambers. The resulting measurements are converted into ambient dose equivalents by conversion factors. In the present work, an experimental study of the relationship between the air-kerma and the operational quantity ambient dose equivalent was conducted using different experimental scenarios. This study was done by measuring the primary x-ray spectra and x-ray spectra transmitted through materials used in dedicated chest radiographic facilities, using a CdTe detector. The air-kerma to ambient dose equivalent conversion coefficients were calculated from these measured spectra. The resulting values of the quantity ambient dose equivalent using these conversion coefficients are more realistic than those available in the literature, because they consider the real energy distribution of primary and transmitted x-ray beams. The maximum difference between the obtained conversion coefficients and the constant value recommended in national and international radiation protection standards is 53.4%. The conclusion based on these results is that a constant coefficient may not be adequate for deriving the ambient dose equivalent. PMID:26835613

  2. Primary Beam Air Kerma Dependence on Distance from Cargo and People Scanners

    Energy Technology Data Exchange (ETDEWEB)

    Strom, Daniel J.; Cerra, Frank

    2016-06-01

    The distance dependence of air kerma or dose rate of the primary radiation beam is not obvious for security scanners of cargo and people in which there is relative motion between a collimated source and the person or object being imaged. To study this problem, one fixed line source and three moving-source scan-geometry cases are considered, each characterized by radiation emanating perpendicular to an axis. The cases are 1) a stationary line source of radioactive material, e.g., contaminated solution in a pipe; 2) a moving, uncollimated point source of radiation that is shuttered or off when it is stationary; 3) a moving, collimated point source of radiation that is shuttered or off when it is stationary; and 4) a translating, narrow “pencil” beam emanating in a flying-spot, raster pattern. Each case is considered for short and long distances compared to the line source length or path traversed by a moving source. The short distance model pertains mostly to dose to objects being scanned and personnel associated with the screening operation. The long distance model pertains mostly to potential dose to bystanders. For radionuclide sources, the number of nuclear transitions that occur a) per unit length of a line source, or b) during the traversal of a point source, is a unifying concept. The “universal source strength” of air kerma rate at a meter from the source can be used to describe x-ray machine or radionuclide sources. For many cargo and people scanners with highly collimated fan or pencil beams, dose varies as the inverse of the distance from the source in the near field and with the inverse square of the distance beyond a critical radius. Ignoring the inverse square dependence and using inverse distance dependence is conservative in the sense of tending to overestimate dose.

  3. Product estimate of air kerma-area and the air kerma in the input surface of the skin of pediatric patients undergoing chest X-ray; Estimativa do produto kerma ar-area e do kerma ar na superficie de entrada da pele de pacientes pediatricos submetidos a radiografia de torax

    Energy Technology Data Exchange (ETDEWEB)

    Villa-Chan, Beatriz; Carvalho, Aline; Andrade, Marcos Ely A.; Barros, Vinicius S.M. de; Khoury, Helen J., E-mail: beatrizvillachan@gmail.com, E-mail: alinecx90@gmail.com, E-mail: marcos.ely@gmail.com, E-mail: vsmdbarros@gmail.com, E-mail: hjkhoury@gmail.com [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear

    2014-07-01

    The aim of this paper is to evaluate the entrance air kerma (Ka,e) and the product air kerma-area (Pka) for chest examinations performed with pediatric patients in a large public hospital of Recife. For this study 89 examinations of patient with ages from zero to 10 years old were evaluated. The results showed that the mean Ka,e values, for patients of 0-1 years old, 1-5 years old and 5-10 years old, were, respectively, 100 mGy, 120 mGy and 100 mGy. The Pka values for newborn patients range from 11,9 to 58,4 mGy.cm{sup 2}, for patients with 1 to 5 years old range from 17 to 192 mGy.cm{sup 2}, and from 30,4 to 136,2 mGy.cm{sup 2} for patients with ages from 5 to 10 years old. The differences in the Pka values are due the different dimensions of the radiation field. For the results its possible to conclude that the Pka values are high, in special for patients with ages from 1 to 5 years old, indicating that the collimation of the radiation field is not adequate. (author)

  4. Transmission ionization chambers for measurements of air collision kerma integrated over beam area. Factors limiting the accuracy of calibration

    International Nuclear Information System (INIS)

    Kerma-area product meters (KAP meters) are frequently used in diagnostic radiology to measure the integral of air-collision kerma over an area A(∫A Kc,air dA) perpendicular to the x-ray beam. In this work, a precise method for calibrating a KAP meter to measure ∫A Kc,air dA is described and calibration factors determined for a broad range of tube potentials (40-200kV). The integral is determined using a large number of TL dosimeters spread over and outside the nominal field area defined as the area within 50% of maximum Kc,air. The method is compared to a simplified calibration method which approximates the integral by multiplying the kerma in the centre of the field by the nominal field area Anom. While the calibration factor using the precise method is independent of field area and distance from the source, that using the simplified method depends on both. This can be accounted for by field inhomogeneities caused by the heel effect, extrafocal radiation and scattered radiation from the KAP meter. The deviations between the calibration factors were as large as ±15% for collimator apertures of 5-100cm2 and distances from the source of 50 - 160 cm. The uncertainty in the calibration factor using the precise method was carefully evaluated and the expanded relative uncertainty estimated to be ±3% with a confidence level of 95%. (author)

  5. Conversion of Airborne Gamma ray Spectra to Ground Level Air Kerma Rates

    DEFF Research Database (Denmark)

    Bargholz, Kim; Korsbech, Uffe C C

    1997-01-01

    A new method for relating airborne gamma-ray spectra to dose rates and kerma rates at ground level is presented. Dependent on flying altitude 50 m to 125 m the method gives correct results for gamma energies above 250 keV respective 350 keV. At lower energies the method underestimate the dose...... or kerma rates; by having a large fraction of the ground level gamma-rays at energies below 350 keV special care should be taken at an interpretation of the results....

  6. Distribution of kerma rate in the air inside of hemodynamic room for typical projections of interventionist cardiology procedures

    International Nuclear Information System (INIS)

    The evaluation of dose to physicians involved in Interventional Cardiology (IC) is an extreme important matter due to the high and non-uniform distribution of dose values. The radiation control during each procedure is complex and the reasons for the high exposures have many different causes. Many international recommendations have already been written aiming the radiation protection optimization in IC. In Brazil, there is not any special orientation for the protection of those occupational persons, nor a specific legislation. The purpose of this work is to evaluate the air kerma rate at critical anatomic regions of the occupationally exposed staff that carry out IC procedures, in representative incidences in order to give subsidies for individual monitoring procedures implementation and to give more information about their radiation protection. The air kerma rate has been measured in the often used condition in the two more common IC procedures namely angiography and coronary angioplasty, using an adult patient simulator irradiated under RAO, LAO and AP projections for fluoro and digital acquisition modes. The measurements have been made in 45 points around the examination table at 5 different representatives heights of: eyes lens, thorax, hands, gonads and knees. AP projection shows the smaller scattered radiation contributions and a more homogeneous exposure distribution. The digital acquisition mode gives air kerma rates about 4 times higher than fluoro mode for LAO projection in the position occupied by the interventionist doctor, the anesthetist and the nursing staff. The most critical anatomic regions are: knees and gonads (without protection). On the physician hands position, values as high as 5 mGy/h have been measured, which can overpass, depending on the number of procedures done, the individual occupational annual limit. Therefore, in IC it is necessary to implement additional protection tools, elaborate safety guides (based on international experiences

  7. 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)

  8. Air-kerma strength determination of a new directional {sup 103}Pd source

    Energy Technology Data Exchange (ETDEWEB)

    Aima, Manik, E-mail: aima@wisc.edu; Reed, Joshua L.; DeWerd, Larry A.; Culberson, Wesley S. [Department of Medical Physics, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin 53705 (United States)

    2015-12-15

    Purpose: A new directional {sup 103}Pd planar source array called a CivaSheet™ has been developed by CivaTech Oncology, Inc., for potential use in low-dose-rate (LDR) brachytherapy treatments. The array consists of multiple individual polymer capsules called CivaDots, containing {sup 103}Pd and a gold shield that attenuates the radiation on one side, thus defining a hot and cold side. This novel source requires new methods to establish a source strength metric. The presence of gold material in such close proximity to the active {sup 103}Pd region causes the source spectrum to be significantly different than the energy spectra of seeds normally used in LDR brachytherapy treatments. In this investigation, the authors perform air-kerma strength (S{sub K}) measurements, develop new correction factors for these measurements based on an experimentally verified energy spectrum, and test the robustness of transferring S{sub K} to a well-type ionization chamber. Methods: S{sub K} measurements were performed with the variable-aperture free-air chamber (VAFAC) at the University of Wisconsin Medical Radiation Research Center. Subsequent measurements were then performed in a well-type ionization chamber. To realize the quantity S{sub K} from a directional source with gold material present, new methods and correction factors were considered. Updated correction factors were calculated using the MCNP 6 Monte Carlo code in order to determine S{sub K} with the presence of gold fluorescent energy lines. In addition to S{sub K} measurements, a low-energy high-purity germanium (HPGe) detector was used to experimentally verify the calculated spectrum, a sodium iodide (NaI) scintillating counter was used to verify the azimuthal and polar anisotropy, and a well-type ionization chamber was used to test the feasibility of disseminating S{sub K} values for a directional source within a cylindrically symmetric measurement volume. Results: The UW VAFAC was successfully used to measure the S

  9. Poster — Thur Eve — 24: Commissioning and preliminary measurements using an Attix-style free air ionization chamber for air kerma measurements on the BioMedical Imaging and Therapy beamlines at the Canadian Light Source

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, D [Department of Oncology, University of Alberta, Edmonton, AB (Canada); McEwen, M; Shen, H [Ionizing Radiation Standards, National Research Council of Canada, Ottawa, ON (Canada); Siegbahn, EA [Department of Medical Physics, Stockholm University, Stockholm (Sweden); Fallone, BG; Warkentin, B [Department of Oncology, University of Alberta, Edmonton, AB (Canada); Department of Medical Physics, Cross Cancer Institute, Edmonton, AB (Canada)

    2014-08-15

    Synchrotron facilities, including the Canadian Light Source (CLS), provide opportunities for the development of novel imaging and therapy applications. A vital step progressing these applications toward clinical trials is the availability of accurate dosimetry. In this study, a refurbished Attix-style (cylindrical) free air chamber (FAC) is tested and used for preliminary air kerma measurements on the two BioMedical Imaging and Therapy (BMIT) beamlines at the CLS. The FAC consists of a telescoping chamber that relies on a difference measurement of collected charge in expanded and collapsed configurations. At the National Research Council's X-ray facility, a Victoreen Model 480 FAC was benchmarked against two primary standard FACs. The results indicated an absolute accuracy at the 0.5% level for energies between 60 and 150 kVp. A series of measurements were conducted on the small, non-uniform X-ray beams of the 05B1-1 (∼8 – 100 keV) and 05ID-2 (∼20 – 200 keV) beamlines for a variety of energies, filtrations and beam sizes. For the 05B1-1 beam with 1.1 mm of Cu filtration, recombination corrections of less than 5 % could only be achieved for field sizes no greater than 0.5 mm × 0.6 mm (corresponding to an air kerma rate of ∼ 57 Gy/min). Ionic recombination thus presents a significant challenge to obtaining accurate air kerma rate measurements using this FAC in these high intensity beams. Future work includes measurements using a smaller aperture to sample a smaller and thus more uniform beam area, as well as experimental and Monte Carlo-based investigation of correction factors.

  10. Comparison of air kerma measurements for tungsten anode based mammography x-ray beam qualities (EURAMET.RI(I)-S4.1)

    Science.gov (United States)

    Csete, I.; Büermann, L.; Gomola, I.

    2016-01-01

    A comparison of the air kerma standards for x-radiation qualities used in mammography was performed between the PTB and the IAEA. Two reference-class ionization chamber types Radcal RC6M and Magna A650 of the IAEA and tungsten anode based beam qualities with Mo and Al external filtrations (W+Mo, W+Al) established at both laboratories were selected for the comparison. The calibration coefficients, NK_air, were determined for the transfer chambers at the PTB in May 2015 and before and after this at the IAEA Dosimetry Laboratory. The results show good agreement, to be well within the 0.55 % standard uncertainty of the comparison. Correction factors to determine NK_air for these beam qualities based on calibration in RQR-M mammography beam qualities, established according to the IEC 61267 standard, were also calculated for the Radcal RC6M, 10X5-6M, and Magna A650 types of chambers. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  11. Conversion coefficients from air kerma to personal dose equivalent H{sub p}(3) fir eye-lens dosimetry; Coeficients de conversion du kerma dans l'air a l'equivalent de dose individuel H{sub p}(3) pour la dosimetrie du cristalin

    Energy Technology Data Exchange (ETDEWEB)

    Daures, J.; Gouriou, J.; Bordy, J.M

    2009-07-01

    This work has been performed within the frame of the European Union ORAMED project (Optimization of Radiation protection for Medical staff). The main goal of the project is to improve standards of protection for medical staff for procedure resulting in potentially high exposures and to develop methodologies for better assessing and for reducing exposures to medical staff. The Work Package WP2 is involved in the development of practical eye lens dosimetry in interventional radiology. This study is complementary of the part of the ENEA report concerning the calculations with the MCNP code of the conversion factors related to the operational quantity H{sub p}(3). A set of energy and angular dependent conversion coefficients H{sub p}(3)/K{sub air} in the new proposed square cylindrical phantom of ICRU tissue, have been calculated with the Monte-Carlo code PENELOPE. The H{sub p}(3) values have been determined in terms of absorbed dose, according to the definition of this quantity, and also with the kerma approximation as formerly reported in ICRU reports. At low photon energy, up to 1 MeV, the two sets of conversion coefficients are consistent. Nevertheless, the differences increase at higher energy. This is mainly due to the lack of electronic equilibrium, especially for small angle incidences. The values of the conversion coefficients obtained with the code MCNP published by ENEA, agree with the kerma approximation calculations with PENELOPE. They are coherent with previous calculations in phantoms different in shape. But above 1 MeV, differences between conversion coefficient values calculated with the absorbed dose and with kerma approximation are significantly increasing, especially at low incidence angles. At those energies the electron transport has to be simulated. (author)

  12. Distribution of kerma rate in the air inside of hemodynamic room for typical projections of interventionist cardiology procedures; Distribuicao da taxa de kerma no ar em uma sala de hemodinamica para projecoes tipicas de procedimentos de cardiologia intervencionista

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez, Mirtha Elizabet Gamarra

    2008-07-01

    The evaluation of dose to physicians involved in Interventional Cardiology (IC) is an extreme important matter due to the high and non-uniform distribution of dose values. The radiation control during each procedure is complex and the reasons for the high exposures have many different causes. Many international recommendations have already been written aiming the radiation protection optimization in IC. In Brazil, there is not any special orientation for the protection of those occupational persons, nor a specific legislation. The purpose of this work is to evaluate the air kerma rate at critical anatomic regions of the occupationally exposed staff that carry out IC procedures, in representative incidences in order to give subsidies for individual monitoring procedures implementation and to give more information about their radiation protection. The air kerma rate has been measured in the often used condition in the two more common IC procedures namely angiography and coronary angioplasty, using an adult patient simulator irradiated under RAO, LAO and AP projections for fluoro and digital acquisition modes. The measurements have been made in 45 points around the examination table at 5 different representatives heights of: eyes lens, thorax, hands, gonads and knees. AP projection shows the smaller scattered radiation contributions and a more homogeneous exposure distribution. The digital acquisition mode gives air kerma rates about 4 times higher than fluoro mode for LAO projection in the position occupied by the interventionist doctor, the anesthetist and the nursing staff. The most critical anatomic regions are: knees and gonads (without protection). On the physician hands position, values as high as 5 mGy/h have been measured, which can overpass, depending on the number of procedures done, the individual occupational annual limit. Therefore, in IC it is necessary to implement additional protection tools, elaborate safety guides (based on international experiences

  13. SU-E-P-15: Technique Factor Modulation and Reference Plane Air Kerma Rates in Response to Simulated Patient Thickness Variations for a Sample of Current Generation Fluoroscopes

    International Nuclear Information System (INIS)

    Purpose: To evaluate and compare approaches to technique factor modulation and air kerma rates in response to simulated patient thickness variations for four state-of-the-art and one previous-generation interventional fluoroscopes. Methods: A polymethyl methacrylate (PMMA) phantom was used as a tissue surrogate for the purposes of determining fluoroscopic reference plane air kerma rates, kVp, mA, and spectral filtration over a wide range of simulated tissue thicknesses. Data were acquired for each fluoroscopic and acquisition dose curve within a default abdomen or body imaging protocol. Results: The data obtained indicated vendor- and model-specific variations in the approach to technique factor modulation and reference plane air kerma rates across a range of tissue thicknesses. Some vendors have made hardware advances increasing the radiation output capabilities of their fluoroscopes; this was evident in the acquisition air kerma rates. However, in the imaging protocol evaluated, all of the state-of-the-art systems had relatively low air kerma rates in the fluoroscopic low-dose imaging mode as compared to the previous-generation unit. Each of the newest-generation systems also employ copper filtration in the selected protocol in the acquisition mode of imaging; this is a substantial benefit, reducing the skin entrance dose to the patient in the highest dose-rate mode of fluoroscope operation. Conclusion: Understanding how fluoroscopic technique factors are modulated provides insight into the vendor-specific image acquisition approach and provides opportunities to optimize the imaging protocols for clinical practice. The enhanced radiation output capabilities of some of the fluoroscopes may, under specific conditions, may be beneficial; however, these higher output capabilities also have the potential to lead to unnecessarily high dose rates. Therefore, all parties involved in imaging, including the clinical team, medical physicists, and imaging vendors, must work

  14. SU-E-P-15: Technique Factor Modulation and Reference Plane Air Kerma Rates in Response to Simulated Patient Thickness Variations for a Sample of Current Generation Fluoroscopes

    Energy Technology Data Exchange (ETDEWEB)

    Wunderle, K [Cleveland Clinic Foundation, Cleveland, OH& Wayne State University School of Medicine, Detroit, MI (United States); Rakowski, J [Wayne State University School of Medicine, Detroit, MI (United States); Dong, F [Cleveland Clinic Foundation, Cleveland, OH (United States)

    2015-06-15

    Purpose: To evaluate and compare approaches to technique factor modulation and air kerma rates in response to simulated patient thickness variations for four state-of-the-art and one previous-generation interventional fluoroscopes. Methods: A polymethyl methacrylate (PMMA) phantom was used as a tissue surrogate for the purposes of determining fluoroscopic reference plane air kerma rates, kVp, mA, and spectral filtration over a wide range of simulated tissue thicknesses. Data were acquired for each fluoroscopic and acquisition dose curve within a default abdomen or body imaging protocol. Results: The data obtained indicated vendor- and model-specific variations in the approach to technique factor modulation and reference plane air kerma rates across a range of tissue thicknesses. Some vendors have made hardware advances increasing the radiation output capabilities of their fluoroscopes; this was evident in the acquisition air kerma rates. However, in the imaging protocol evaluated, all of the state-of-the-art systems had relatively low air kerma rates in the fluoroscopic low-dose imaging mode as compared to the previous-generation unit. Each of the newest-generation systems also employ copper filtration in the selected protocol in the acquisition mode of imaging; this is a substantial benefit, reducing the skin entrance dose to the patient in the highest dose-rate mode of fluoroscope operation. Conclusion: Understanding how fluoroscopic technique factors are modulated provides insight into the vendor-specific image acquisition approach and provides opportunities to optimize the imaging protocols for clinical practice. The enhanced radiation output capabilities of some of the fluoroscopes may, under specific conditions, may be beneficial; however, these higher output capabilities also have the potential to lead to unnecessarily high dose rates. Therefore, all parties involved in imaging, including the clinical team, medical physicists, and imaging vendors, must work

  15. Comparison of air kerma measurements between the PTB and the IAEA for x-radiation qualities used in general diagnostic radiology and mammography

    Science.gov (United States)

    Csete, István; Büermann, Ludwig; Gomola, Igor; Girzikowsky, Reinhard

    2013-01-01

    A comparison of the air kerma standards for x-radiation qualities used in general diagnostic radiology and mammography, identified as EURAMET.RI(I)-S10 (EURAMET project #1221), was performed between the PTB and the IAEA. Two spherical and two parallel-plate reference-class ionization chambers of the IAEA and 12 beam qualities standardized in the IEC standard 61267:2005 plus 7 additional standard beam qualities established at both laboratories were selected for the comparison. The calibration coefficients were determined for the transfer chambers at the PTB in September 2012 and before and after this at the IAEA Dosimetry Laboratory. The results show the calibration coefficients of both laboratories to be in good agreement within the standard uncertainty of the comparison of about 0.47%. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by EURAMET, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  16. European inter-comparison of Monte Carlo codes users for the uncertainty calculation of the kerma in air beside a caesium-137 source; Intercomparaison europeenne d'utilisateurs de codes monte carlo pour le calcul d'incertitudes sur le kerma dans l'air aupres d'une source de cesium-137

    Energy Technology Data Exchange (ETDEWEB)

    De Carlan, L.; Bordy, J.M.; Gouriou, J. [CEA Saclay, LIST, Laboratoire National Henri Becquerel, Laboratoire de Metrologie de la Dose 91 - Gif-sur-Yvette (France)

    2010-07-01

    Within the frame of the CONRAD European project (Coordination Network for Radiation Dosimetry), and more precisely within a work group paying attention to uncertainty assessment in computational dosimetry and aiming at comparing different approaches, the authors report the simulation of an irradiator containing a caesium 137 source to calculate the kerma in air as well as its uncertainty due to different parameters. They present the problem geometry, recall the studied issues (kerma uncertainty, influence of capsule source, influence of the collimator, influence of the air volume surrounding the source). They indicate the codes which have been used (MNCP, Fluka, Penelope, etc.) and discuss the obtained results for the first issue

  17. Implementation of the method air-kerma product area in KAP camera calibration with reference qualities of X-ray series at the SSDL RQR of Mexico

    International Nuclear Information System (INIS)

    The X-Ray machines, at a reference laboratory for the instrument calibration in diagnostic radiology, should compliance with the ISO requirements. Sometimes there is not available as much laboratories as needed in Latin American countries. So this project shows the KAP ionization chamber implementation method using the TRS-457 radiation quality from the IAEA at the SSDL of Mexico. The KAP instruments calibration method consists in doing a substitution comparison using a standard reference with traceability to a primary laboratory and a transmission-monitoring chamber that measures the number of photons of the X-ray primary beam. A KAP chamber calibration requires a special array that consists in collocating the chamber in two different positions of its calibration process. Then, with air kerma-area product coefficient together with a corrected electrometer measure at referential conditions, the patient dosimetry magnitudes are calculated. The dosimetry necessity at hospitals always will be in function of possessing a highly reliable calibration coefficient chamber for making these measures. That dosimetry results will help in reducing the total or partial irradiation emitted to the human body of the patient. This is how stochastic risks will be lessened due to diagnostic studies. The purpose of this project is to have a synergy with calibration for making known that the SSDL of Mexico has the technical capacity to act as a link between primary standard dosimetry laboratories and the ionizing radiation equipment users who require that their KAP chamber have traceability from the primary standard to the user. (author)

  18. Kerma in the air at entry surface in thorax pediatric examinations at public hospital in Parana, Brazil

    International Nuclear Information System (INIS)

    This work consisted in the evaluation of the entrance skin air kerma (ESAK) in pediatric chest x-ray examinations. A study of 186 exams in anterior-posterior, posterior-anterior and lateral projections was carried out for patients with ages ranging from 0 to 15 years. The ESAK was measured with the DoseCal software and Li-Fl thermoluminescent dosimeters. The results were compared with measurements done recently at the same place and with the reference dose values established by the European Community. It was observed that the optimization of the technique and the routine changes suggested in the previous study were not maintained. The charge (mAs) and the ESAK values found in the present study were much higher than the previous one, and the voltage (kVp) values found was lower. The results suggest that the implementation of the Quality Assurance Program could adequate these parameters to the established levels and keep the pediatric examinations more uniform. (author)

  19. Calibration of a 7.6 cm x 7.6 cm (3 inch x 3 inch) Sodium Iodide Gamma Ray Spectrometer for Air Kerma Rate

    Energy Technology Data Exchange (ETDEWEB)

    Grasty, R.L.; Walters, B.R.B.; Hovgaard, J.; LaMarre, J.R

    2001-07-01

    An experimental procedure is described for converting a gamma ray spectral measurement from a 7.6 cm x 7.6 cm (3 inch x 3 inch) sodium iodide (NaI) detector to air kerma rate. The calibration procedure involves measuring the energy deposited in the detector using 10 radioactive sources of known activity covering an energy range from 60 keV to 1836 keV. For each of the 10 sources, gamma ray spectra were measured with the source at different angles to the detector axis. The total energy deposited in the detector for the ten sources was confirmed by Monte Carlo calculations. The spectra measured at different angles were combined to produce a spectrum that would represent a homogeneous semi-infinite source of radiation. The resultant spectrum was then subdivided into 10 energy regions. Based on the known air kerma rates due to the sources, a calibration coefficient was calculated for each of the 10 energy regions. These calibration coefficients could then be used to convert the energy deposited in the 10 regions of an unknown spectrum to air kerma rate. The calibration procedure was confirmed by comparing the results from the detector with those from calibrated collimated beams of {sup 137}Cs and {sup 60}Co. A comparison of measurements using a calibrated pressurised ionisation chamber with those from a similar NaI spectrometer in Finland provided additional confirmation of the calibration procedure. (author)

  20. Comparison of mammography radiation dose values obtained from direct incident air kerma measurements with values from measured X-ray spectral data

    Energy Technology Data Exchange (ETDEWEB)

    Assiamah, M. [Health Physics Service/Schonland Research Institute for Nuclear Sciences, University of the Witwatersrand, Private Bag 3, Wits 2050, Johannesburg (South Africa); Nam, T.L. [Health Physics Service/Schonland Research Institute for Nuclear Sciences, University of the Witwatersrand, Private Bag 3, Wits 2050, Johannesburg (South Africa)]. E-mail: nam@schonlan.src.wits.ac.za; Keddy, R.J. [Health Physics Service/Schonland Research Institute for Nuclear Sciences, University of the Witwatersrand, Private Bag 3, Wits 2050, Johannesburg (South Africa)

    2005-04-01

    The application of X-rays and ionising radiations for diagnostic radiology requires that the procedure is justified and optimised and that the exposure to the patient is kept as low as possible, without compromising image information. X-ray mammography is considered to be the most sensitive technique currently available for early detection of breast cancer. The magnitude of the absorbed radiation dose to the breast from mammography X-ray beams forms an important part of the quality control of the mammographic examination since it gives an indication of the performance of the mammographic imaging system as well as an estimated risk to the patient. In this work mean glandular dose (MGD) values were obtained at various tube potentials and tube loadings (TL) using direct measurements of the incident air kerma (ESAK) at the surface of a standard breast phantom and also from spectral measurements acquired with a solid-state detector. Comparisons of the MGD values thus derived are presented and the relationship between MGD, phantom thickness, image quality and tube operating parameters is discussed.

  1. Implementation of the method air-kerma product area in KAP camera calibration with reference qualities of X-ray series at the SSDL RQR of Mexico; Implementacion del metodo producto kerma en aire-area en la calibracion de camaras KAP con calidades de referencia de rayos X de la serie RQR en el LSCD de Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Cejudo, Jesus; Tovar, Victor M., E-mail: jesus.cejudo@ini.gob.mx, E-mail: victor.tovar@inin.gob.mx [lnstituto Nacional de lnvestigaciones Nucleares (DMRI/LSDC/lNlN), Ocoyoacac (Mexico). Centro Nuclear Dr. Nabor Carrillo Flores. Laboratorio Secundario de Calibracion Dosimetrica

    2013-10-01

    The X-Ray machines, at a reference laboratory for the instrument calibration in diagnostic radiology, should compliance with the ISO requirements. Sometimes there is not available as much laboratories as needed in Latin American countries. So this project shows the KAP ionization chamber implementation method using the TRS-457 radiation quality from the IAEA at the SSDL of Mexico. The KAP instruments calibration method consists in doing a substitution comparison using a standard reference with traceability to a primary laboratory and a transmission-monitoring chamber that measures the number of photons of the X-ray primary beam. A KAP chamber calibration requires a special array that consists in collocating the chamber in two different positions of its calibration process. Then, with air kerma-area product coefficient together with a corrected electrometer measure at referential conditions, the patient dosimetry magnitudes are calculated. The dosimetry necessity at hospitals always will be in function of possessing a highly reliable calibration coefficient chamber for making these measures. That dosimetry results will help in reducing the total or partial irradiation emitted to the human body of the patient. This is how stochastic risks will be lessened due to diagnostic studies. The purpose of this project is to have a synergy with calibration for making known that the SSDL of Mexico has the technical capacity to act as a link between primary standard dosimetry laboratories and the ionizing radiation equipment users who require that their KAP chamber have traceability from the primary standard to the user. (author)

  2. Doses monitoring in radiology: calibration of air kerma-area product (PKA meters

    Directory of Open Access Journals (Sweden)

    Ricardo Andrade Terini

    2013-12-01

    Full Text Available Objective The authors have sought to study the calibration of a clinical PKA meter (Diamentor E2 and a calibrator for clinical meters (PDC in the Laboratory of Ionizing Radiation Metrology at Instituto de Energia e Ambiente - Universidade de São Paulo. Materials and Methods Different qualities of both incident and transmitted beams were utilized in conditions similar to a clinical setting, analyzing the influence from the reference dosimeter, from the distance between meters, from the filtration and from the average beam energy. Calibrations were performed directly against a standard 30 cm3 cylindrical chamber or a parallel-plate monitor chamber, and indirectly against the PDC meter. Results The lowest energy dependence was observed for transmitted beams. The cross calibration between the Diamentor E2 and the PDC meters, and the PDC presented the greatest propagation of uncertainties. Conclusion The calibration coefficient of the PDC meter showed to be more stable with voltage, while the Diamentor E2 calibration coefficient was more variable. On the other hand, the PDC meter presented greater uncertainty in readings (5.0% than with the use of the monitor chamber (3.5% as a reference.

  3. Effect of fluoroscopic X-ray beam spectrum on air-kerma measurement accuracy: implications for establishing correction coefficients on interventional fluoroscopes with KAP meters.

    Science.gov (United States)

    Wunderle, Kevin A; Rakowski, Joseph T; Dong, Frank F

    2016-01-01

    The first goal of this study was to investigate the accuracy of the displayed reference plane air kerma (Ka,r) or air kerma-area product (Pk,a) over a broad spectrum of X-ray beam qualities on clinically used interventional fluoroscopes incorporating air kerma-area product meters (KAP meters) to measure X-ray output. The second goal was to investigate the accuracy of a correction coefficient (CC) determined at a single beam quality and applied to the measured Ka,r over a broad spectrum of beam qualities. Eleven state-of-the-art interventional fluoroscopes were evaluated, consisting of eight Siemens Artis zee and Artis Q systems and three Philips Allura FD systems. A separate calibrated 60 cc ionization chamber (external chamber) was used to determine the accuracy of the KAP meter over a broad range of clinically used beam qualities. For typical adult beam qualities, applying a single CC deter-mined at 100 kVp with copper (Cu) in the beam resulted in a deviation of < 5% due to beam quality variation. This result indicates that applying a CC determined using The American Association of Physicists in Medicine Task Group 190 protocol or a similar protocol provides very good accuracy as compared to the allowed ± 35% deviation of the KAP meter in this limited beam quality range. For interventional fluoroscopes dedicated to or routinely used to perform pediatric interventions, using a CC established with a low kVp (~ 55-60 kVp) and large amount of Cu filtration (~ 0.6-0.9 mm) may result in greater accuracy as compared to using the 100 kVp values. KAP meter responses indicate that fluoroscope vendors are likely normalizing or otherwise influencing the KAP meter output data. Although this may provide improved accuracy in some instances, there is the potential for large discrete errors to occur, and these errors may be difficult to identify. PMID:27167287

  4. 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

  5. Calculation of conversion factor of Kerma in the air for ambient dose equivalent in radiotherapy; Calculo dos fatores de conversao de Kerma no ar para equivalente de dose ambiental em radioterapia

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Marco Antonio Frota

    2000-03-01

    This work aims to estimate the average conversion factor of Kerma in air to H {sup *} (10) using photon beams coming from clinic linear accelerators, transmitted through concrete walls of a radiotherapic treatment room. The transmitted photon spectra by both 1 meter and 2 meters concrete walls, in an area of 40 x 40 cm{sup 2}, were calculated when the primary beam impart in an angle of 0 deg. The (secondary) photon beams transmitted respectively by 0,5 meter, 1,0 meter, 1,0 meter and 2,0 meter concrete walls, after they scattered by an angle of 90 deg in a cylindric phantom inside the room, were also determined. Generally, 50 millions of histories were computed for each simulation made for the primary beam. For the 90 deg spread, the number of histories was 100 millions. The computational code used on this work was the MCNP4B. The most common clinic accelerators used on radiotheraphic treatments were used on this work CLINAC-4, CLINAC-6, CLINAC-18 and CLINAC-2500. From the spectra analysis obtained in this work, it was possible to dispose the conversion factor for realistic beams found in radiotherapeutic establishment. (author)

  6. Kerma in the air at entry surface in thorax pediatric examinations at public hospital in Parana, Brazil; Kerma no ar na superficie de entrada em exames pediatricos de torax em hospital publico no Parana, Brasil

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Amanda; Porto, Lorena; Bunick, Ana; Paschuk, Sergei; Denyak, Valeriy, E-mail: schelin@utfpr.edu.b [Universidade Tecnologica Federal do Parana (UTFPR), Curitiba, PR (Brazil); Schelin, Hugo; Tilly, Joao, E-mail: joao.tilly@derax.com.b [DERAX Desenvolvimento Radiologico, Curitiba, PR (Brazil); Khoury, Helen, E-mail: hjkhoury@gmail.co [Universidade Federal de Pernambuco (DOIN/UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear. Grupo de Dosimetria e Instrumentacao Nuclear; Ferreira, Jose [Universidade Estadual do Oeste do Parana (UNIOESTE), Cascavel, PR (Brazil)

    2011-07-01

    This work consisted in the evaluation of the entrance skin air kerma (ESAK) in pediatric chest x-ray examinations. A study of 186 exams in anterior-posterior, posterior-anterior and lateral projections was carried out for patients with ages ranging from 0 to 15 years. The ESAK was measured with the DoseCal software and Li-Fl thermoluminescent dosimeters. The results were compared with measurements done recently at the same place and with the reference dose values established by the European Community. It was observed that the optimization of the technique and the routine changes suggested in the previous study were not maintained. The charge (mAs) and the ESAK values found in the present study were much higher than the previous one, and the voltage (kVp) values found was lower. The results suggest that the implementation of the Quality Assurance Program could adequate these parameters to the established levels and keep the pediatric examinations more uniform. (author)

  7. Estimation of mean-glandular dose from monitoring breast entrance skin air kerma using a high sensitivity metal oxide semiconductor field effect transistor (MOSFET) dosimeter system in mammography.

    Science.gov (United States)

    Dong, S L; Chu, T C; Lee, J S; Lan, G Y; Wu, T H; Yeh, Y H; Hwang, J J

    2002-12-01

    Estimation of mean-glandular dose (MGD) has been investigated in recent years due to the potential risks of radiation-induced carcinogenesis associated with the mammographic examination for diagnostic radiology. In this study, a new technique for immediate readout of breast entrance skin air kerma (BESAK) using high sensitivity MOSFET dosimeter after mammographic projection was introduced and a formula for the prediction of tube output with exposure records was developed. A series of appropriate conversion factors was applied to the MGD determination from the BESAK. The study results showed that signal response of the high sensitivity MOSFET exhibited excellent linearity within mammographic dose ranges, and that the energy dependence was less than 3% for each anode/filter combination at the tube potentials 25-30 kV. Good agreement was observed between the BESAK and the tube exposure output measurement for breasts thicker than 30 mm. In addition, the air kerma estimated from our prediction formula provided sufficient accuracy for thinner breasts. The average MGD from 120 Asian females was 1.5 mGy, comparable to other studies. Our results suggest that the high sensitivity MOSFET dosimeter system is a good candidate for immediately readout of BESAK after mammographic procedures.

  8. Control letters and uncertainties of the kerma patterns in air, dose absorbed in water and dose absorbed in air of the LSCD; Cartas de control e incertidumbres de los patrones de kerma en aire, dosis absorbida en agua y dosis absorbida en aire del LSCD

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez R, M.T.; Tovar M, V.M.; Cejudo A, J. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2005-12-15

    With the purpose of characterizing the component of uncertainty of long term of the patron ionization chambers of the LSCD, for the magnitudes: speed of kerma in air {kappa}{sub {alpha}}{sub {center_dot}}, dose speed absorbed in water D{alpha}{sub {center_dot}}, and speed absorbed dose in air D{alpha}{sub {center_dot}}, it use the technique of letters of control l-MR/S. This statistical technique it estimates the component of uncertainty of short term by means of the deviation standard inside groups {sigma}{sub {omega}} and that of long term by means of the standard deviation among groups {sigma}{sub {beta}}, being this it finishes an estimator of the stability of the patterns.The letters of control l-MR/S it construct for: i) {kappa}{sub {alpha}}{sub {center_dot}}, in radiation field of {sup 60}Co for patterns: primary CC01 series 131, secondary NE 2611 series 176, secondary PTW TN30031 series 578 and Third PTW W30001 series 365. ii) D{alpha}),en radiation field of {sup 60}Co for patterns: primary CC01 series 131, Secondary PTW TN30031 series 578 and tertiary PTW W30001 series 365. iii) I-MR/S with extrapolation chamber PTW primary pattern, measurement realizes in secondary patron fields of {sup 90}Sr-{sup 90}Y. The expanded uncertainty U it is calculated of agreement with the Guide of the ISO/BIPM being observed the following thing: a. In some the cases {sigma}{sub {beta}}, is the component of the U that more contributed to this. Therefore, it is necessary to settle down technical of sampling in those mensurations that allow to reduce the value of {sigma}{sub {beta}}. For example with sizes of subgroup {eta}{sub {approx}} 30 data, or with a number of subgroups {kappa}{sub {>=}}. That which is achieved automating the mensuration processes. b.The component of the temperature is also one of those that but they contribute to the U, of there the necessity of: to recover the tracking for this magnitude of it influences and to increase the precision in the

  9. Investigation of photon spectra and contributions to air kerma rates in the environment near nuclear facilities using portable germanium gamma spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, G.J. [Centre for Environment, Fisheries and Aquaculture Science, Lowestoft (United Kingdom)

    2000-05-01

    Portable spectrometers based on NaI or Ge detectors are now important additions to the tools available for monitoring and assessment of radioactivity and radiation dose rates in the environment due to both natural and anthropogenic sources. The high resolution of the Ge detector is of particular use in rapidly identifying and assessing radionuclides of significance. Portable spectrometry is of importance in assessing deposited activity and contributions to air kerma rates, and the rapid availability of these results would be significant in the event of a nuclear emergency in addition to the more usual application of measuring concentrations of radionuclides in environmental samples. In the course of developing a portable germanium detector system, spectra were measured at a number of locations in the environment near nuclear establishments in the UK. These spectra are presented and analysed in this paper in terms of the radionuclide contributions and gamma air kerma rates. Particular features are highlighted. First, background contributions are characterised using an example spectrum measured at Lowestoft beach, where anthropogenic influences are low. By contrast, near the Magnox nuclear power station at Bradwell, Essex there are contributions to the spectra due to photons from {sup 16}N, {sup 41}Ar and {sup 60}Co. In the Ravenglass estuary near Sellafield, {sup 137}Cs features prominently, with smaller contributions due to other radionuclides discharged in liquid waste from Sellafield. In the Ribble estuary which is influenced by discharges from the Springfields fuel fabrication plant as well as from Sellafield, measurements were made on a houseboat at high and low tide; there was a significant difference in the contribution due to {sup 137}Cs from Sellafield. Upstream of the Springfields works, peaks in the spectrum were observed due to {sup 234}Th and {sup 234m}Pa due to discharges from the site, as well as {sup 137}Cs from BNFL Sellafield. The paper highlights

  10. Reference dosimetry at the Australian Synchrotron's imaging and medical beamline using free-air ionization chamber measurements and theoretical predictions of air kerma rate and half value layer

    Energy Technology Data Exchange (ETDEWEB)

    Crosbie, Jeffrey C.; Rogers, Peter A. W. [Department of Obstetrics and Gynaecology, University of Melbourne, The Royal Women' s Hospital, Parkville, Victoria 3052 (Australia); Stevenson, Andrew W. [CSIRO Materials Science and Engineering, Clayton, Victoria 3169 (Australia); Hall, Christopher J. [Imaging and Medical Beamline, Australian Synchrotron, Clayton, Victoria 3168 (Australia); Lye, Jessica E. [Australian Radiation Protection and Nuclear Safety Agency, Yallambie, Victoria 3085 (Australia); Nordstroem, Terese [KTH Royal Institute of Technology, Stockholm SE-100 44 (Sweden); Midgley, Stewart M. [School of Physics, Monash University, Clayton, Victoria 3800 (Australia); Lewis, Robert A. [Department of Medical Imaging and Radiation Sciences, Monash University, Clayton, Victoria 3800 (Australia)

    2013-06-15

    Purpose: Novel, preclinical radiotherapy modalities are being developed at synchrotrons around the world, most notably stereotactic synchrotron radiation therapy and microbeam radiotherapy at the European Synchrotron Radiation Facility in Grenoble, France. The imaging and medical beamline (IMBL) at the Australian Synchrotron has recently become available for preclinical radiotherapy and imaging research with clinical trials, a distinct possibility in the coming years. The aim of this present study was to accurately characterize the synchrotron-generated x-ray beam for the purposes of air kerma-based absolute dosimetry. Methods: The authors used a theoretical model of the energy spectrum from the wiggler source and validated this model by comparing the transmission through copper absorbers (0.1-3.0 mm) against real measurements conducted at the beamline. The authors used a low energy free air ionization chamber (LEFAC) from the Australian Radiation Protection and Nuclear Safety Agency and a commercially available free air chamber (ADC-105) for the measurements. The dimensions of these two chambers are different from one another requiring careful consideration of correction factors. Results: Measured and calculated half value layer (HVL) and air kerma rates differed by less than 3% for the LEFAC when the ion chamber readings were corrected for electron energy loss and ion recombination. The agreement between measured and predicted air kerma rates was less satisfactory for the ADC-105 chamber, however. The LEFAC and ADC measurements produced a first half value layer of 0.405 {+-} 0.015 and 0.412 {+-} 0.016 mm Cu, respectively, compared to the theoretical prediction of 0.427 {+-} 0.012 mm Cu. The theoretical model based upon a spectrum calculator derived a mean beam energy of 61.4 keV with a first half value layer of approximately 30 mm in water. Conclusions: The authors showed in this study their ability to verify the predicted air kerma rate and x-ray attenuation

  11. Neutron kerma factors, and water equivalence of some tissue substitutes

    Energy Technology Data Exchange (ETDEWEB)

    Singh, V. P.; Badiger, N. M. [Karnatak University, Department of Physics, Dharwad, 580003 (India); Vega C, H. R., E-mail: kudphyvps@rediffmail.com [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico)

    2014-08-15

    The kerma factors and kerma relative to air and water of 24 compounds used as tissue substitutes were calculated for neutron energy from 2.53 x 10{sup -8} up to 29 MeV. The kerma ratio of the tissue substitutes relative to air and water were calculated by the ratio of kerma factors of the tissue substitute to air and water respectively. The water equivalence of the selected tissue substitutes was observed above neutron energies 100 eV. Kerma ratio relative to the air for Poly-vinylidene fluoride and Teflon are found to be nearest to unity in very low energy (up to 1 eV) and above 63 eV respectively. It was found that the natural rubber as a water equivalent tissue substitute compound. The results of the kerma factors in our investigation shows a very good agreement with those published in ICRU-44. We found that at higher neutron energies, the kerma factors and kerma ratios of the selected tissue substitute compounds are approximately same, but differences are large for energies below 100 eV. (Author)

  12. Estudo comparativo da qualidade da imagem e do kerma, de entrada e de saída, em simulador de tórax utilizando sistemas analógico e digitalizado CR de aquisição de imagens Comparative study of image quality and entrance and exit air kerma measurements on chest phantom utilizing analog and CR digital imaging systems

    Directory of Open Access Journals (Sweden)

    Renata Matos da Luz

    2010-02-01

    Full Text Available OBJETIVO: O processo de migração de sistemas analógicos para digitalizados, para aplicações diagnósticas, requer cuidados específicos, a fim de manter a qualidade das imagens e minimizar a dose no paciente. Este trabalho tem como objetivo analisar e comparar a qualidade da imagem e o kerma num simulador não antropomórfico de tórax gerados por sistemas analógicos e digitalizados CR. MATERIAIS E MÉTODOS: Foram analisados a qualidade da imagem e o kerma, de entrada e saída, no simulador para dois equipamentos de raios X diferentes (Siemens e Emic, com diferentes sistemas de retificação de onda (12 pulsos e alta frequência. Ambos os sistemas (analógico e digitalizado estavam sendo utilizados no mesmo local. Foram geradas imagens em filme e em image plates. RESULTADOS: Foi observado aumento na tensão e/ou na carga transportada pelo tubo de raios X quando houve a migração para o sistema CR, para manutenção das características diagnósticas da imagem. Isto resultou em aumento de kerma coletado. CONCLUSÃO: As maiores diferenças determinadas (aumento de dose e redução da qualidade da imagem foram observadas no equipamento com retificação de onda de 12 pulsos e transdutor de imagem CR (image plates.OBJECTIVE: The process of migration from analog to digital imaging system requires specific attention to preserve images quality and minimizing the dose to the patients. The present study was aimed at analyzing and comparing images quality and entrance and exist air kerma measurements in a non-anthropomorphic chest phantom with analog and CR digital imaging systems. MATERIALS AND METHODS: Two different X-ray units (Siemens and Emic with different wave rectification systems (12-pulse and high-frequency were utilized in a single institution along the process of migration from analog to CR digital imaging system. Images were acquired on films and image plates. RESULTS: An increase on the X-ray tube peak voltage and/or load was observed

  13. Modelling the contribution of individual radionuclides to the total gamma air kerma rate for the sediments of the Ribble Estuary, NW England

    International Nuclear Information System (INIS)

    The aim of this study was to test the performance of a published dose-rate model, investigate the contribution of individual radionuclides to the total gamma air kerma rate (GAKR) and derive external doses to man in the Ribble Estuary, NW England. GAKRs were measured and sediment cores were collected in order to determine radionuclide specific activities with depth. The latter values were used as input data for the external dose-rate model. The model has a slight tendency to over-predict the GAKR, but, on average, the model predictions fall within ±26% of the measured value. Improvements, in the present case, might be made by accounting for core shortening and variations in soil density in the input data. The model predicted that, for exposed intertidal mud sites, a range of GAKRs between 0.011 and 0.022 μGy h-1 was attributable to Springfields discharges alone. The contribution due to 234mPa and 234Th ranged between 20 and 60%. An excess GAKR (GAKR arising from anthropogenic emissions alone) of 0.139-0.150 μGy μGy h-1, used in conjunction with relevant habit-survey data (for a potential critical group) and conversion factors, yielded a dose to man of 0.029-0.031 mSv year-1. (author)

  14. Air kerma to HP(3) conversion coefficients for photons from 10 keV to 10 MeV, calculated in a cylindrical phantom.

    Science.gov (United States)

    Gualdrini, G; Bordy, J M; Daures, J; Fantuzzi, E; Ferrari, P; Mariotti, F; Vanhavere, F

    2013-05-01

    In the framework of the ORAMED project (Optimization of RAdiation protection for MEDical staff), funded by the European Union Seventh Framework Programme, different studies were aimed at improving the quality of radiation protection in interventional radiology and nuclear medicine. The main results of the project were presented during a final workshop held in Barcelona in January 2011, the proceedings of which are available in the open literature. One of the ORAMED tasks was focused on the problem of eye-lens photon exposure of the medical staff, a topic that gained more importance especially after the ICRP decision to lower the limiting equivalent dose to 20 mSv per year. The present technical note has the scope, besides briefly summarising the physical reasons of the proposal and the practical implications, to provide, in tabular form, a set of air kerma to Hp(3) conversion coefficients based on the adoption of a theoretical cylindrical model that is well suited for reproduction of the mass and the shape of a human head.

  15. Stability results of a free air ionization chamber in standard mammography beams

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Natalia F.; Xavier, Marcos; Vivolo, Vitor; Caldas, Linda V.E., E-mail: nsilva@ipen.br, E-mail: mxavier@ipen.br, E-mail: vivolo@ipen.br, E-mail: lcaldas@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    Free air ionization chambers are absolute dosimeters, because they can measure basic physical quantities directly without the need of their calibration in a standard radiation beam. They are used for measuring exposure and air kerma in X and gamma radiation beams. The Calibration Laboratory (LCI) of IPEN has a free air ionization chamber of the cylindrical type for low energies. The characterization of this ionization chamber was already performed and reported in a previous study. After a modification in the support of the micrometers used for the movement of the internal cylinder devices, the tests were redone. The objective of this work was to present the new alignment protocol of the free air ionization chamber in low energies of X-ray beams of standard mammography qualities, assuring the positioning reproducibility, and new results of stability tests performed with the application of this protocol will be presented. (author)

  16. A synthetic zero air standard

    Science.gov (United States)

    Pearce, Ruth

    2016-04-01

    A Synthetic Zero Air Standard R. E. Hill-Pearce, K. V. Resner, D. R. Worton, P. J. Brewer The National Physical Laboratory Teddington, Middlesex TW11 0LW UK We present work towards providing traceability for measurements of high impact greenhouse gases identified by the World Meteorological Organisation (WMO) as critical for global monitoring. Standards for these components are required with challengingly low uncertainties to improve the quality assurance and control processes used for the global networks to better assess climate trends. Currently the WMO compatibility goals require reference standards with uncertainties of < 100 nmolmol-1 for CO2 (northern hemisphere) and < 2 nmolmol-1 for CH4 and CO. High purity zero gas is required for both the balance gas in the preparation of reference standards and for baseline calibrations of instrumentation. Quantification of the amount fraction of the target components in the zero gas is a significant contributor to the uncertainty and is challenging due to limited availability of reference standard at the amount fraction of the measurand and limited analytical techniques with sufficient detection limits. A novel dilutor was used to blend NPL Primary Reference Gas Mixtures containing CO2, CH4 and CO at atmospheric amount fractions with a zero gas under test. Several mixtures were generated with nominal dilution ratios ranging from 2000:1 to 350:1. The baseline of two cavity ring down spectrometers was calibrated using the zero gas under test after purification by oxidative removal of CO and hydrocarbons to < 1 nmolmol-1 (SAES PS15-GC50) followed by the removal of CO2 and water vapour to < 100 pmolmol-1 (SAES MC190). Using the standard addition method.[1] we have quantified the amount fraction of CO, CO2, and CH4 in scrubbed whole air (Scott Marrin) and NPL synthetic zero air. This is the first synthetic zero air standard with a matrix of N2, O2 and Ar closely matching ambient composition with gravimetrically assigned

  17. Doses monitoring in radiology: calibration of air kerma-area product (P{sub KA}) meters; Monitoracao de doses em radiologia: a calibracao de medidores do produto kerma-area (P{sub KA})

    Energy Technology Data Exchange (ETDEWEB)

    Terini, Ricardo Andrade; Campelo, Maria Carolina de Santana; Almeida Junior, Jose Neres de, E-mail: rterini@pucsp.br [Pontificia Universidade Catolica de Sao Paulo (PUC-SP), SP (Brazil); Herdade, Silvio Bruni; Pereira, Marco Aurelio Guedes [Universidade de Sao Paulo (IEE/USP), SP (Brazil). Instituto de Energia e Ambiente

    2013-11-15

    Materials and methods: different qualities of both incident and transmitted beams were utilized in conditions similar to a clinical setting, analyzing the influence from the reference dosimeter, from the distance between meters, from the filtration and from the average beam energy. Calibrations were performed directly against a standard 30 cm{sup 3} cylindrical chamber or a parallel-plate monitor chamber, and indirectly against the PDC meter. Results: the lowest energy dependence was observed for transmitted beams. The cross calibration between the Diamentor E2 and the PDC meters, and the PDC presented the greatest propagation of uncertainties. Conclusion: the calibration coefficient of the PDC meter showed to be more stable with voltage, while the Diamentor E2 calibration coefficient was more variable. On the other hand, the PDC meter presented greater uncertainty in readings (5.0%) than with the use of the monitor chamber (3.5%) as a reference. (author)

  18. X Ray Spectrometry of Low Energy Photons for Determining Conversion Coefficients from Air Kerma, Ka, to Personal Dose Equivalent, Hp(10), for Radiation Qualities of the ISO Narrow Spectrum Series

    International Nuclear Information System (INIS)

    The pulse height spectra of the radiation qualities N-10 to N-120 of the ISO narrow spectrum series (N) were measured using a commercial Ge spectrometer and a specially designed lead collimator. For the unfolding of these spectra, three response matrices of the Ge spectrometer for different maximum energies and energy resolutions were calculated by the EGS4 (Electron Gamma Shower version 4) code incorporating the PRESTA and LSCAT options. Then, the pulse height spectra were unfolded with two different algorithms to check the correctness. To verify the measuring and unfolding method, the first half value layers (HVLs) were determined using small ionisation chambers and the fluence spectra. The mean photon energies were calculated, also on the basis of the fluence spectra, and compared with published values. For each radiation quality N-10 to N-120 the conversion coefficients hpK(10;N,α) from air kerma Ka to personal dose equivalent at 10mm depth, Hp (10,α), were calculated for angles of incidence α of 15, 30, 45, 60 deg. and 75 deg. between the unidirectional photon field and the normal to the slab phantom surface. Because the fluence spectra were influenced by the air density, in particular the low energy spectra, the hpK(10;N,α) values were normalised to reference conditions. Differences of up to about 88% between the hpK(10;N,α) values presented in this work and those given in ISO/FDIS 4037-3 were found. (author)

  19. Practical method for determination of air kerma by use of an ionization chamber toward construction of a secondary X-ray field to be used in clinical examination rooms.

    Science.gov (United States)

    Maehata, Itsumi; Hayashi, Hiroaki; Kimoto, Natsumi; Takegami, Kazuki; Okino, Hiroki; Kanazawa, Yuki; Tominaga, Masahide

    2016-07-01

    We propose a new practical method for the construction of an accurate secondary X-ray field using medical diagnostic X-ray equipment. For accurate measurement of the air kerma of an X-ray field, it is important to reduce and evaluate the contamination rate of scattered X-rays. To determine the rate quantitatively, we performed the following studies. First, we developed a shield box in which an ionization chamber could be set at an inner of the box to prevent detection of the X-rays scattered from the air. In addition, we made collimator plates which were placed near the X-ray source for estimation of the contamination rate by scattered X-rays from the movable diaphragm which is a component of the X-ray equipment. Then, we measured the exposure dose while changing the collimator plates, which had diameters of 25-90 mm(ϕ). The ideal value of the exposure dose was derived mathematically by extrapolation to 0 mm(ϕ). Tube voltages ranged from 40 to 130 kV. Under these irradiation conditions, we analyzed the contamination rate by the scattered X-rays. We found that the contamination rates were less than 1.7 and 2.3 %, caused by air and the movable diaphragm, respectively. The extrapolated value of the exposure dose has been determined to have an uncertainty of 0.7 %. The ionization chamber used in this study was calibrated with an accuracy of 5 %. Using this kind of ionization chamber, we can construct a secondary X-ray field with an uncertainty of 5 %.

  20. Norma Primaria de calidad del aire AIR QUALITY STANDARD

    Directory of Open Access Journals (Sweden)

    PATRICIA MATUS C.

    2002-04-01

    Full Text Available Las normas primarias de calidad del aire tienen por finalidad proteger la salud de la población de la contaminación atmosférica. Ellas establecen un nivel de riesgo socialmente aceptado. Este artículo describe los antecedentes considerados durante el proceso de actualización de la regulación vigente en Chile. Detalla conceptos sobre la calidad del aire, describe los efectos en la salud de los contaminantes, y el procedimiento seguido para fijar los nuevos estándares Finaliza enumerando la norma primaria de calidad del aire, sus valores y los limites definidos para ser considerados en el ámbito de la gestión de los episodios críticos o de alta contaminaciónThe main purpose of air quality standards is to protect people health from air pollution. They establish a socially accepted level of risk. This article describes the background information considered during the process for updating the current Chilean regulation. Concepts about quality of air, and the effects of the pollutants on the health are described. The procedure followed to fix the new standards is detailed. Finally we state the primary air quality norm, its values as well as the critical limits in order to control critical events of high air pollution

  1. SU-E-I-27: Estimating KERMA Area Product for CT Localizer Images

    International Nuclear Information System (INIS)

    Purpose: To estimate the free-in-air KERMA-Area Product (KAP) incident on patients due to CT localizer scans for common CT exams. Methods: In-plane beam intensity profiles were measured in localizer acquisition mode using OSLs for a 64 slice MDCT scanner (Lightspeed VCT, GE Medical Systems, Waukesha WI). The z-axis beam width was measured as a function of distance from isocenter. The beam profile and width were used to calculate a weighted average air KERMA per unit mAs as a function of intercepted x-axis beam width for objects symmetric about the localizer centerline.Patient areas were measured using manually drawn regions and divided by localizer length to determine average width. Data were collected for 50 head exams (lateral localizer only), 15 head/neck exams, 50 chest exams, and 50 abdomen/pelvis exams. Mean patient widths and acquisition techniques were used to calculate the weighted average free-in-air KERMA, which was multiplied by the patient area to estimate KAP. Results: Scan technique was 120 kV tube voltage, 10 mA current, and table speed of 10 cm/s. The mean ± standard deviation values of KAP were 120 ± 11.6, 469 ± 62.6, 518 ± 45, and 763 ± 93 mGycm2 for head, head/neck, chest, and abdomen/pelvis exams, respectively. For studies with AP and lateral localizers, the AP/lateral area ratio was 1.20, 1.33, and 1.24 for the head/neck, chest, and abdomen/pelvis exams, respectively. However, the AP/lateral KAP ratios were 1.12, 1.08, and 1.07, respectively. Conclusion: Calculation of KAP in CT localizers is complicated by the non-uniform intensity profile and z-axis beam width. KAP values are similar to those for simple radiographic exams such as a chest radiograph and represent a small fraction of the x-ray exposure at CT. However, as CT doses are reduced the localizer contribution will be a more significant fraction of the total exposure

  2. Air quality standards must protect public health

    Energy Technology Data Exchange (ETDEWEB)

    Norman Edelman [American Lung Association (ALA) (United States)

    2006-06-15

    Leading medical and public health organizations are deeply concerned about the proposed revisions to the National Ambient Air Quality Standard (NAAQS) that the US Environmental Protection Agency (EPA) announced in December 2005. Led by the American Lung Association (ALA), these groups are fighting to force EPA to finalize stricter standards for fine and coarse particles when the final decision is announced in September 2006. The ALA disagrees strongly with the proposal to exempt coarse particles from agriculture and mining sources, and to exclude communities with populations fewer than 100,000 from protection and monitoring requirements. ALA urges EPA to set the following health-based NAAQS for PM: Annual average PM2.5 standard of 12 {mu}mg/m{sup 3}; 24 hour average PM2.5 standard of 25 {mu}mg.m{sup 3} (99th percentile); 24-hour average PM10-2.5 standard of 25-30 {mu}g/m{sup 3} (99th percentile), applied equally to all areas of the country and to all types of particles. 72 refs., 2 figs., 1 tab.

  3. 77 FR 30087 - Air Quality Designations for the 2008 Ozone National Ambient Air Quality Standards

    Science.gov (United States)

    2012-05-21

    ... for the 2008 Ozone National Ambient Air Quality Standards; Implementation of the 2008 National Ambient Air Quality Standards for Ozone: Nonattainment Area Classifications Approach, Attainment Deadlines and... Quality Standards AGENCY: Environmental Protection Agency (EPA). ACTION: Final rule. SUMMARY: This...

  4. 75 FR 2938 - National Ambient Air Quality Standards for Ozone

    Science.gov (United States)

    2010-01-19

    ... the air quality criteria and standards for O 3 in September 2000 with a call for information (65 FR... CFR Parts 50 and 58 RIN 2060-AP98 National Ambient Air Quality Standards for Ozone AGENCY... primary and secondary national ambient air quality standards (NAAQS) for ozone (O 3 ) set in March...

  5. Measurement of the ambient gamma dose equivalent and kerma from the small 252Cf source at 1 meter and the small 60Co source at 2 meters

    Energy Technology Data Exchange (ETDEWEB)

    Carl, W. F. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-07-30

    NASA Langley Research Center requested a measurement and determination of the ambient gamma dose equivalent rate and kerma at 100 cm from the 252Cf source and determination of the ambient gamma dose equivalent rate and kerma at 200 cm from the 60Co source for the Radiation Budget Instrument Experiment (Rad-X). An Exradin A6 ion chamber with Shonka air-equivalent plastic walls in combination with a Supermax electrometer were used to measure the exposure rate and free-in-air kerma rate of the two sources at the requested distances. The measured gamma exposure, kerma, and dose equivalent rates are tabulated.

  6. 40 CFR 52.14 - State ambient air quality standards.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 3 2010-07-01 2010-07-01 false State ambient air quality standards. 52... quality standards. Any ambient air quality standard submitted with a plan which is less stringent than a national standard is not considered part of the plan....

  7. Tissue kerma vs distance relationships for initial nuclear radiation from the atomic bombs Hiroshima and Nagasaki

    International Nuclear Information System (INIS)

    Initial nuclear radiation is comprised of prompt neutrons and prompt primary gamma rays from an exploding nuclear device, prompt secondary gamma rays produced by neutron interactions in the environment, and delayed neutrons and delayed fission-product gamma rays from the fireball formed after the nuclear device explodes. These various components must all be considered in establishing tissue kerma vs distance relationships which describe the decrease of initial nuclear radiation with distance in Hiroshima and Nagasaki. An interest in initial nuclear radiation at distances of as much as 2000 m from the hypocenter demands the use of discrete ordinates transport (DOT) techniques. The two-dimensional (2D) DOT-IV code developed at Oak Ridge National Laboratory (ORNL) was used to calculate the tissue kerma in an air-over-ground geometry from prompt neutrons and prompt primary gamma rays and from prompt secondary gamma rays produced in air and in soil. Data from the Los Alamos National Laboratory (LANL) were used as the source terms. The tissue kerma at ground level from delayed fission-product gamma rays and delayed neutrons, was investigated using the NUIDEA code developed by Science Applications, Inc., (SAI). This code incorporates very detailed models which can take into account such features as the immediate rise of the fireball, the rapid radioactive decay of fission-products in it, and the perturbation of the atmosphere by the explosion. Tissue kerma vs distance relationships obtained by summing results of these current state-of-the-art calculations will be discussed. Our results clearly show that the prompt secondary gamma rays and delayed fission-product gamma rays are the dominant components of the total tissue kerma from initial nuclear radiation of the atomic (or pure-fission) devices detonated over Hiroshima and Nagasaki. (author)

  8. Survivor dosimetry. Part A. Fluence-to-kerma conversion coefficients

    International Nuclear Information System (INIS)

    An important step in the dosimetry evaluation is to relate the radiation passing through a unit volume of a material of interest (fluence) to the energy release (kerma) in the material, which determines the absorbed dose. The fluence-to-kerma conversion coefficients or 'kerma coefficients' used in the Dosimetry System 1986 (DS86) are taken from Kerr (1982). These kerma coefficients are based on body tissue compositions for Reference Man from the International Commission on Radiological Protection (1975) and Kerr (1982), the mass energy-absorption coefficients for photons from Hubbell (1982), and the elemental kerma coefficients for neutrons from Caswell et al. (1980). Hence, the kerma coefficients used in DS86 are approximately 20 years old. In order to provide an updated set of kerma coefficients for use in the Dosimetry System 2002 (DS02), a new evaluation has been completed. This new evaluation considered recently suggested changes in the composition of soft tissues of the body in ICRU Report 44 (International Commission on Radiation Units and Measurements 1989), the mass energy-absorption coefficients for photons by Hubbell and Seltzer (1996), and the elemental kerma coefficients for neutrons in ICRU Report 63 (International Commission on Radiation Units and Measurements 2000). The new DS02 kerma coefficients for soft tissue are presented as both point-wise data for use in Monte Carlo radiation transport calculations and multigroup data for use in discrete ordinates radiation transport calculations. (author)

  9. Calibration of the indicators of the product KERMa-AREA in radiodiagnostic equipment; Calibracion de los indicadores del producto KERMA-AREA en los equipos de radiodiagnostico

    Energy Technology Data Exchange (ETDEWEB)

    Ginjaume, M.; Jarvinen, H.; Turak, O.

    2013-07-01

    Currently the IAEA proposes two procedures for the calibration of the determination of the PKA systems integrated in the x-ray equipment. The traditional method is to measure air kerma at a certain distance from the focus through an ionization chamber reference and then the area of the field of radiation in that position. The alternative method is based on measuring directly the product kerma-area using equipment calibrated in this magnitude. In both cases the calibration procedure takes into account the position of the tube on the stretcher of the patient. The objective of this study was to compare the practical application of both calibration procedures as well as assess the accuracy of indication of the PKA in the consoles of the radiology equipment. (Author)

  10. 78 FR 30829 - Approval and Promulgation of Air Quality Implementation Plans; Illinois; Air Quality Standards...

    Science.gov (United States)

    2013-05-23

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of Air Quality Implementation Plans; Illinois; Air Quality Standards Revision AGENCY: Environmental Protection Agency (EPA). ACTION: Proposed rule. SUMMARY... current national ambient air quality standards (NAAQS) for ozone, lead, and particulate matter. EPA...

  11. Photon and neutron kerma coefficients for polymer gel dosimeters

    Energy Technology Data Exchange (ETDEWEB)

    El-Khayatt, A.M., E-mail: Ahmed_el_khayatt@yahoo.com [Physics Department, College of Science, Al Imam Mohammad Ibn Saud Islamic University (IMSIU) (Saudi Arabia); Reactor Physics Department, Nuclear Research Centre, Atomic Energy Authority, 13759 Cairo (Egypt); Vega-Carrillo, Hector Rene [Unidad Academica de Estudios Nucleares, Universidad Autonoma de Zacatecas, C. Cipres 10, Fracc. La Peñuela, 98068 Zacatecas, Zac. (Mexico)

    2015-08-21

    Neutron and gamma ray kerma coefficients were calculated for 17 3D dosimeters, for the neutron and gamma ray energy ranges extend from 2.53×10{sup −8} to 29 MeV and from 1.0×10{sup −3} to 20 MeV, respectively. The calculated kermas given here for discrete energies and the kerma coefficients are referred to as “point-wise data”. Curves of gamma ray kermas showed slight dips at about 60 keV for most 3D dosimeters. Also, a noticeable departure between thermal and epithermal neutrons kerma sets for water and polymers has been observed. Finally, the obtained results could be useful for dose estimation in the studied 3D dosimeters. - Highlights: • Neutron and gamma ray kerma coefficients were calculated in 17 3D dosimeters. • Curves of gamma-ray kermas showed slight dips at about 60 keV. • Disagreement between neutron kermas for water and polymers has been observed. • The obtained results could be useful for dose estimation in the studied dosimeters.

  12. Norma Primaria de calidad del aire AIR QUALITY STANDARD

    OpenAIRE

    PATRICIA MATUS C.; RODRIGO LUCERO CH.

    2002-01-01

    Las normas primarias de calidad del aire tienen por finalidad proteger la salud de la población de la contaminación atmosférica. Ellas establecen un nivel de riesgo socialmente aceptado. Este artículo describe los antecedentes considerados durante el proceso de actualización de la regulación vigente en Chile. Detalla conceptos sobre la calidad del aire, describe los efectos en la salud de los contaminantes, y el procedimiento seguido para fijar los nuevos estándares Finaliza enumerando la nor...

  13. 78 FR 30770 - Approval and Promulgation of Air Quality Implementation Plans; Illinois; Air Quality Standards...

    Science.gov (United States)

    2013-05-23

    ... Quality Standards Revision AGENCY: Environmental Protection Agency (EPA). ACTION: Direct final rule... National Ambient Air Quality Standards (NAAQS) for ozone and particulate matter (PM). EPA is approving a... Pollution; Chapter I: Pollution Control Board; Subchapter l: Air Quality Standards And Episodes; Part...

  14. Preparation and determination of kerma for Iridium 192 sources of low dose rate for brachytherapy

    International Nuclear Information System (INIS)

    The practice of Brachytherapy with Iridium-192 sources of low dose rate (0.4 - 0.8 Gy/h) is a technique used in the treatment of diverse illnesses. in this work the preparation, quality control and calibration are presented in terms of kerma in air of Iridium-192 using as target these recycled Iridium-Platinum wires. The targets were obtained as decayed sources of different radio therapeutical centers in the country and they were characterized by Scanning electron microscopy in order to determine their chemical composition. Subsequently it was developed an experimental design to establish the effect of neutron flux, geometrical array and irradiation time over the activity and percentage of the sources homogeneity. The homogeneity was determined by auto radiography and by Gamma spectroscopy. Once the optimal irradiation conditions were established, it is determined the apparent activity and kerma in air using a well type ionization chamber with traceability to a primary laboratory. Iridium-192 sources were obtained with an average homogeneity 96 %, apparent activity 282.129 ± 0.531 M Bq and kerma in air 0.03200 ± 0.00006 m Gy m/h A. (Author)

  15. 78 FR 925 - Air Quality Designations for the 2008 Ozone National Ambient Air Quality Standards: Notice of...

    Science.gov (United States)

    2013-01-07

    ... AGENCY 40 CFR Part 81 Air Quality Designations for the 2008 Ozone National Ambient Air Quality Standards... air quality designations for the 2008 ozone national ambient air quality standards for all areas in... Ambient Air Quality Standards,'' and ``Air Quality Designations for the 2008 Ozone National Ambient...

  16. Aqua AIRS Level 3 8-day Standard Physical Retrieval (AIRS-only) V006

    Data.gov (United States)

    National Aeronautics and Space Administration — The AIRS Only Level 3 8-Day Gridded Retrieval Product contains standard retrieval means, standard deviations and input counts. Each file covers an 8-day period, or...

  17. Design of wind turbines for non-standard air density

    DEFF Research Database (Denmark)

    Soraperra, Giusepe

    2005-01-01

    New site typologies characterized by non-standard air density have been recently considered for wind energy exploitation. The work attempts to assess the effect of air density on turbine performance, whether with variable or fixed speed. Since the power density of the sites with non-standard dens......New site typologies characterized by non-standard air density have been recently considered for wind energy exploitation. The work attempts to assess the effect of air density on turbine performance, whether with variable or fixed speed. Since the power density of the sites with non......-standard density is intrinsically different, it is impossible to reach the standard rated power at the standard rated speed. Three scenarios are possible (i) to keep the standard rated speed of the turbine by changing the size of the electric generator; (ii) to change the rated speed of the turbine by adopting...... a different pitch angel setting; (iii) adoption of extendeders to the blades can also help in restraining the standard rated power at the standard rated speed for p less than pst. The power curves for the three turbine configurations, each in three different air density conformations, have been calculated...

  18. Scattering study at free air ionization chamber diaphragm; Estudo do espalhamento no diafragma da camara de ionizacao de ar livre

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Alexandre Lo Bianco dos

    2011-07-01

    The maim of this work consisted in the assessment of the correction factor for air kerma, due to scattered radiation in the diaphragm of the free-air ionization chamber model 481. LNMRl measurements were made to acquire x-ray spectra corresponding to the Qualities RQR-M, described in IEC 61627 standards (2005). These spectra were used as input data in the MC simulations. The operational range of energy spectra provide up to 35 keV. This energy range is typically used in diagnostic radiology, although there is not primary standard for air kerma. The determination of this factor is a fundamental process in the primary standardization of the air kerma. These factors were obtained by computer simulation using the Penelope code. The results are k{sub RQR-M1}=0,9946, k{sub RQR} {sub -M2}=0,9932, k{sub RQR-M3}=0,9978 and k{sub RQR-M4}=0,9885; with uncertainties of 0,007 and coverage factor equal to 2. lt can be concluded that, with respect to the diaphragm, the chamber can be used in the primary standard of air kerma. (author)

  19. Air Quality of Beijing and Impacts of the New Ambient Air Quality Standard

    Directory of Open Access Journals (Sweden)

    Wei Chen

    2015-08-01

    Full Text Available Beijing has been publishing daily reports on its air quality since 2000, and while the air pollution index (API shows that the air quality has improved greatly since 2000, this is not the perception of Beijing’s residents. The new national ambient air quality standard (NAAQS-2012, which includes the monitoring of PM2.5, has posed stricter standards for evaluating air quality. With the new national standard, the air quality in Beijing is calculated using both NAAQS-2012 and the previous standard. The annual attainment rate has dropped from 75.5% to 50.7%. The spatial analysis of air quality shows that only a background station could attain the national standard, while urban and suburban stations exceed the national standard. Among the six pollutants included in the NAAQS-2012, PM2.5 is the major contributor to the air quality index (AQI comparing with the five other pollutants. The results indicate that under previous NAAQS without PM2.5 monitoring, the air quality has improved greatly in the past decade.  By considering PM2.5, the air quality attainment has dropped greatly. Furthermore, a great effort is needed for local government to bring down the PM2.5 concentration.

  20. 75 FR 521 - National Emission Standards for Hazardous Air Pollutants: Area Source Standards for Prepared...

    Science.gov (United States)

    2010-01-05

    ... provision in 1999 in the Integrated Urban Air Toxics Strategy, (64 FR 38715, July 19, 1999). Specifically... the Integrated Urban Air Toxics Strategy (64 FR 38715, July 19, 1999). A primary goal of the Strategy... Protection Agency 40 CFR Part 63 National Emission Standards for Hazardous Air Pollutants: Area...

  1. State Skill Standards: Heating, Ventilation, Air Conditioning, and Refrigeration

    Science.gov (United States)

    Ball, Larry; Soukup, Dennis

    2006-01-01

    The Department of Education has undertaken an ambitious effort to develop statewide career and technical education skill standards. The standards in this document are for Heating, Ventilation, Air Conditioning and Refrigeration (HVAC&R) programs and are designed to clearly state what the student should know and be able to do upon completion of an…

  2. 78 FR 34177 - Implementation of the 2008 National Ambient Air Quality Standards for Ozone: State Implementation...

    Science.gov (United States)

    2013-06-06

    ... the 2008 National Ambient Air Quality Standards for Ozone: State Implementation Plan Requirements... Ambient Air Quality Standards for Ozone: State Implementation Plan Requirements AGENCY: Environmental... 2008 ozone national ambient air quality standards (NAAQS) (the ``2008 ozone NAAQS'') that...

  3. The use of scientific information in setting ambient air standards.

    OpenAIRE

    Jordan, B C; Richmond, H M; McCurdy, T

    1983-01-01

    The Clean Air Act, as amended in 1977, requires periodic review and revision of all national ambient air quality standards (NAAQS) to insure that they are based on the latest scientific information. This article presents an overview of how EPA currently reviews and establishes NAAQS. The role of scientific information and expertise in the process is illustrated by a review of several key issues faced in the development of the proposed revisions to the carbon monoxide NAAQS. Finally, a risk an...

  4. 76 FR 76048 - Air Quality Designations for the 2008 Lead (Pb) National Ambient Air Quality Standards

    Science.gov (United States)

    2011-12-06

    ... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 81 RIN 2060-AR17 Air Quality Designations for the 2008 Lead (Pb) National Ambient Air Quality Standards Correction In rule document 2011-29460 appearing on pages 72097-72120 in the issues...

  5. MACK, Fluence to Kerma Generator from ENDF/B

    International Nuclear Information System (INIS)

    1 - Nature of physical problem solved: The principal purpose of the program is in calculating pointwise neutron energy release parameters (fluence-to-kerma factors) at an arbitrary energy mesh from nuclear data in ENDF/B format (2). The kerma factors are of prime importance for calculating heating and dose rates in any nuclear system. The program processes all reactions significant to energy deposition. In addition, the program calculates energy group kerma factors and group cross sections by reactions (group constants not transfer matrices) averaged over an arbitrary input weighting function or any of the 'built-in' functions. When resonance data is available, the code calculates the contribution from the resolved and unresolved resonance parameters. The pointwise cross sections, pointwise kerma factors, energy group cross sections and energy group kerma factors can be printed, punched, and/or saved on tape for all reactions and the sum as selected by input. The pointwise kerma factors can be saved for later use (3) to generate group kerma factors for a different energy group structure or possibly for inclusion in the ENDF/B evaluation for the nuclide with the appropriate MT numbers in the 300's series (2). 2 - Method of solution: The expressions for the energy release per reaction are obtained from a solution of the kinematics of nuclear reactions. The anisotropy of elastic and inelastic scattering is considered. The contribution to energy deposition from radioactive decay of the residual nucleus can be added by reaction and is calculated using Fermi theory in the case of beta decay. In the resolved resonance region, MACK accepts either single or multi level Breit-Wigner parameters. Doppler broadening is performed at an arbitrary input temperature. The unresolved resonance treatment includes some shielding effects through a 1/sigma t weighting. The energy group kerma factors and cross sections are calculated by averaging the pointwise data over either a user

  6. 40 CFR 50.8 - National primary ambient air quality standards for carbon monoxide.

    Science.gov (United States)

    2010-07-01

    ... (CONTINUED) AIR PROGRAMS NATIONAL PRIMARY AND SECONDARY AMBIENT AIR QUALITY STANDARDS § 50.8 National primary ambient air quality standards for carbon monoxide. (a) The national primary ambient air quality standards... 40 Protection of Environment 2 2010-07-01 2010-07-01 false National primary ambient air...

  7. Characterization of a free-air ionization chamber in direct X-ray beams as used in mammography

    International Nuclear Information System (INIS)

    At this work stability and characterization tests were undertaken on a Victoreen free-air ionization chamber, model 481. The tests were realized using direct X-ray beams as a contribution for its establishment as a primary standard system of the quantity air kerma. The characterization tests were: saturation curve, ion collection efficiency, polarity effect, response linearity with the air kerma rate and response linearity with the chamber volume variation. The ion collection efficiency allowed the determination of the ion recombination factor. Most of the test results showed agreement with the limits established by international standards. Furthermore, the air attenuation factors for the mammography beams with aluminum and molybdenum filters were obtained. The factors for photon transmission and scattering at the diaphragm edges were also determined for mammography beams with aluminum filter and for the standard beam with molybdenum filter. (author)

  8. The air we breathe : an international comparison of air quality standards and guidelines

    Energy Technology Data Exchange (ETDEWEB)

    Boyd, D.R. [British Columbia Univ., Vancouver, BC (Canada). Inst. for Resources, Environment and Sustainability]|[Simon Fraser Univ., Burnaby, BC (Canada). School of Resource and Environmental Management]|[Victoria Univ., BC (Canada). POLIS Project on Ecological Governance

    2006-08-15

    This document compared Canada's voluntary air quality guidelines with the legally binding national standards in the United States, Europe and Australia, as well as guidelines of the World Health Organization. It was prepared in response to Canada's need for strong national standards for air quality and long-term targets for reducing air pollution to prevent negative health effects. Even low-level contamination of food, drinking water and outdoor air presents a chemical stress to which all people are vulnerable. Adequate laws, policies and commitments by government are needed to guarantee a healthy environment. This comparison revealed that Canada's voluntary guidelines lag behind most western industrialized nations including the United States, Australia, and all members of the European Union. Studies have shown that Canada ranks among the 3 worst industrialized nations for per capita sulphur dioxide and nitrogen dioxide emissions as well as emissions of volatile organic compounds, carbon monoxide and greenhouse gases. The author argued that the key reason for why these emissions continue to be a problem can be attributed to weak laws and guidelines. He argued that unless laws and regulations are strengthened and additional actions taken, pressures from population and economic growth will result in increasing hazardous air emissions. According to the Ontario Medical Association, the direct and indirect costs of air pollution on the health of Canadians are estimated to be in the billions of dollars in lost productivity and work time; direct health care costs; pain and suffering due to non-fatal illness; and, social welfare loss due to premature death. The comparison of air quality standards and guidelines focused on the health effects and sources of ozone, particulate matter, sulphur oxides, nitrogen oxides, carbon monoxide, and lead. The author suggested that in order to provide an adequate level of health protection for Canadians, the federal

  9. Preparation and determination of kerma for Iridium 192 sources of low dose rate for brachytherapy; Preparacion y determinacion del kerma de fuentes de iridio-192 de baja tasa de dosis para braquiterapia

    Energy Technology Data Exchange (ETDEWEB)

    Tendilla, J.I.; Tovar M, V.; Mitsoura, E.; Aguilar H, F.; Alanis M, J. [Instituto Nacional de Investigaciones Nucleares, C.P. 52045-1, Salazar, Esrado de Mexico, D.F. (Mexico)

    2000-07-01

    The practice of Brachytherapy with Iridium-192 sources of low dose rate (0.4 - 0.8 Gy/h) is a technique used in the treatment of diverse illnesses. in this work the preparation, quality control and calibration are presented in terms of kerma in air of Iridium-192 using as target these recycled Iridium-Platinum wires. The targets were obtained as decayed sources of different radio therapeutical centers in the country and they were characterized by Scanning electron microscopy in order to determine their chemical composition. Subsequently it was developed an experimental design to establish the effect of neutron flux, geometrical array and irradiation time over the activity and percentage of the sources homogeneity. The homogeneity was determined by auto radiography and by Gamma spectroscopy. Once the optimal irradiation conditions were established, it is determined the apparent activity and kerma in air using a well type ionization chamber with traceability to a primary laboratory. Iridium-192 sources were obtained with an average homogeneity 96 %, apparent activity 282.129 {+-} 0.531 M Bq and kerma in air 0.03200 {+-} 0.00006 m Gy m/h A. (Author)

  10. Determination and comparison of computed tomography quantities in standard beams using standard adult and pediatric phantoms

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Elaine Wirney; Potiens, Maria da Penha A., E-mail: ewmartins@ipen.br, E-mail: mppalbu@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    The computed tomography (CT) is a segment of diagnostic radiology that uses higher radiation dose comparing to others fields of conventional radiology. In 2011, for decreasing the uncertainty in the diagnostic radiology beams dosimetry, the International Atomic Energy Agency (IAEA) published an implementation on the Technical Reports Series no. 457 from 2007, which is a code of practice recommending procedures for calibration and dosimetry in diagnostic radiology field. The objective of this study was to compare CT measurements on standards beams using adult and pediatric phantoms. The same procedure was used for two types of phantoms. Measurements were performed on the surface of the phantoms obtaining values of entrance surface air kerma (K{sub e}). Measurements were taken from 100 to 150 kV (RQT 8, 9 and RQT 10), with the center of the simulators positioned at a distance of 100 cm from the focal spot. The values for the CT quantities air kerma index (in free air, C{sub K}, and in phantom, C{sub PMMA,C} / C{sub PMMA,P}) and air kerma length product (P{sub KA}) were found. The results were significant and the largest difference between the two phantoms was found for the radiation quality RQT 10. (author)

  11. 40 CFR 50.15 - National primary and secondary ambient air quality standards for ozone.

    Science.gov (United States)

    2010-07-01

    ... air quality standards for ozone. 50.15 Section 50.15 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS NATIONAL PRIMARY AND SECONDARY AMBIENT AIR QUALITY STANDARDS § 50.15 National primary and secondary ambient air quality standards for ozone. (a) The level of...

  12. 40 CFR 50.6 - National primary and secondary ambient air quality standards for PM10.

    Science.gov (United States)

    2010-07-01

    ... air quality standards for PM10. 50.6 Section 50.6 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS NATIONAL PRIMARY AND SECONDARY AMBIENT AIR QUALITY STANDARDS § 50.6 National primary and secondary ambient air quality standards for PM10. (a) The level of the...

  13. 40 CFR 50.12 - National primary and secondary ambient air quality standards for lead.

    Science.gov (United States)

    2010-07-01

    ... air quality standards for lead. 50.12 Section 50.12 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS NATIONAL PRIMARY AND SECONDARY AMBIENT AIR QUALITY STANDARDS § 50.12 National primary and secondary ambient air quality standards for lead. (a) National primary and...

  14. 40 CFR 50.4 - National primary ambient air quality standards for sulfur oxides (sulfur dioxide).

    Science.gov (United States)

    2010-07-01

    ... PROTECTION AGENCY (CONTINUED) AIR PROGRAMS NATIONAL PRIMARY AND SECONDARY AMBIENT AIR QUALITY STANDARDS § 50.4 National primary ambient air quality standards for sulfur oxides (sulfur dioxide). Link to an... applicable to all areas notwithstanding the promulgation of SO2 national ambient air quality standards...

  15. 40 CFR 50.16 - National primary and secondary ambient air quality standards for lead.

    Science.gov (United States)

    2010-07-01

    ... air quality standards for lead. 50.16 Section 50.16 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS NATIONAL PRIMARY AND SECONDARY AMBIENT AIR QUALITY STANDARDS § 50.16 National primary and secondary ambient air quality standards for lead. (a) The national primary...

  16. Establishment of a primary standard system for low energy X-rays using a free air ionization chamber; Estabelecimento de um sistema padrao primario para raios-X de energias baixas com uma camara de ionizacao de ar livre

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Natalia Fiorini da

    2016-08-01

    In this work a primary standard system was established for low energy X-rays (10 kV to 50 kV), using a free air ionization chamber with concentric cylinders, Victoreen (Model 481-5), at the Calibration Laboratory of Instruments (LCI) of the Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP). For this, a new ionization chamber alignment protocol was developed for the radiation system and a modification on the micrometer housing used for the movement of the internal cylinders was ma de. The results obtained for the stability and characterization tests showed to be within the limits established by the standards IEC 61674 and IEC 60731. The correction factors for photon attenuation in the air, transmission and scattering in the diaphragm, scattering and fluorescence and ion recombination were also determined. These values were compared with those obtained by the German primary standard laboratory, Physikalisch-Technische Bundesanstalt (PTB), showing good agreement. Finally, the absolute values of the quantity air kerma rate for the standard qualities direct beams MWV28 and WMV35 and the attenuated beams WMH28 and WMH35 were determined; the results are in agreement, with a maximum difference of 3,8% with the values obtained using the secondary standard system of LCI. (author)

  17. An empirical bayes method for comparing air pollution data to air quality standards

    Science.gov (United States)

    Suggs, Jack C.; Curran, Thomas C.

    Air pollution concentrations are often characterized by skewed distributions. For example, 24-h suspended particulate mass concentrations have historically been characterized by a 2-parameter lognormal distribution (Larsen, 1969, J. Air. Pollut. Control. Ass.19, 24-30). The error in making measurements of these concentrations also conforms to a distribution that is more symmetric and can usually be approximated by the normal distribution, often with the added feature that the error variation is a function of concentration level. Air pollution measurements are often used to determine status with respect to legal standards such as the National Ambient Air Quality Standards (NAAQS) (Fed. Reg. 36, 8186, 1971; 44, 8202, 1979). In general, these standards do not explicitly account for measurement error. Using Bayesian mathematics, a model is developed which deals with the probability of the "true" concentration exceeding the NAAQS given a measurement above the NAAQS. Several hypothetical examples are used to demonstrate that Bayesian techniques can combine both pollution history and instrument precision into a probablistic model for comparing air pollution data to NAAQS.

  18. PTRAC File Utilization for Calculation of Free-Air Ionization Chamber Correction Factors by MCNPX

    Science.gov (United States)

    Šolc, Jaroslav; Sochor, Vladimír

    2014-06-01

    A free-air ionization chamber is used as a standard of photon air-kerma. Several correction factors are applied to the air-kerma value. Correction factors for electron loss (kloss) and for additional ionization current caused by photon scatter (ksc), photon fluorescence (kfl), photon transmission through diaphragm edge (kdtr), and photon scatter from the surface of the diaphragm aperture (kdsc) were determined by the MCNPX code utilizing information stored in Particle Track (PTRAC) output files. Individual steps of the procedure are described and the calculated values of the correction factors are presented. The values are in agreement with the correction factors published in a literature for similar free-air chambers.

  19. Information draft on the development of air standards for chloroform

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-01-01

    Chloroform is used as a grain fumigant and a solvent for pesticides, adhesives, fats, oils, rubbers, alkaloids and waxes. It is also a chemical intermediate for dyes and pesticides, a component of cough syrups, toothpastes, and liniments. It is used in fire extinguishers, in the manufacture of refrigerants, propellants, plastics, anesthetics and pharmaceuticals. Of the releases into the air in 1996 in Ontario (36.7 tonnes), over 96 per cent was attributed to the pulp and paper industry. Chloroform is well absorbed in exposed animals and humans through ingestion, inhalation, and dermal contact. Once absorbed, the chloroform distributes throughout the entire body. Metabolism of chloroform involves cytochrome P-450 in an oxidative biotransformation to produce trichloromethanol with phosgene as its intermediate product and finally hydrochloric acid and carbon dioxide. Chloroform is a central nervous system depressant and a gastrointestinal irritant. Exposure to chloroform can cause fainting, vomiting, dizziness, nausea, fatique and headache. Its most universally observed toxic effect is liver damage. Chloroform is not known to be carcinogenic in humans, but there is sufficient evidence to suggest that it is an animal carcinogen. The current Ontario air quality standard and criterion for chloroform was established in 1979. The half-hour interim POI standard is 1,500 microgram/cubic meter, and the 24-hour AAQC is 500 microgram/cubic meter. This document reviews the scientific and technical information relevant to setting an ambient air quality standard for chloroform in Ontario. The information is gathered from standards and guidelines developed by the federal government, the US Environmental Protection Agency, the World Health Organization, Scandinavia, the Netherlands, and various American states. 59 refs., 1 tab., appendix.

  20. 77 FR 16547 - Radionuclide National Emission Standards for Hazardous Air Pollutants; Notice of Construction...

    Science.gov (United States)

    2012-03-21

    ... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION AGENCY Radionuclide National Emission Standards for Hazardous Air Pollutants; Notice of Construction... modification of sources subject to the Radionuclide National Emission Standards for Hazardous Air...

  1. 76 FR 15266 - National Emission Standards for Hazardous Air Pollutants; Notice of Reconsideration

    Science.gov (United States)

    2011-03-21

    ... Pollutants; Notice of Reconsideration AGENCY: Environmental Protection Agency (EPA). ACTION: Notice of... aspects of the national emission standards for hazardous air pollutants (NESHAP) for new and existing... Standards for Hazardous Air Pollutants for Major Sources: Industrial, Commercial, and Institutional...

  2. Characterization of a free-air ionization chamber in direct X-ray beams as used in mammography; Caracterizacao de uma camara de ionizacao de ar-livre em feixes diretos de raios X utilizados em mamografia

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Mateus Hilario de

    2014-08-01

    At this work stability and characterization tests were undertaken on a Victoreen free-air ionization chamber, model 481. The tests were realized using direct X-ray beams as a contribution for its establishment as a primary standard system of the quantity air kerma. The characterization tests were: saturation curve, ion collection efficiency, polarity effect, response linearity with the air kerma rate and response linearity with the chamber volume variation. The ion collection efficiency allowed the determination of the ion recombination factor. Most of the test results showed agreement with the limits established by international standards. Furthermore, the air attenuation factors for the mammography beams with aluminum and molybdenum filters were obtained. The factors for photon transmission and scattering at the diaphragm edges were also determined for mammography beams with aluminum filter and for the standard beam with molybdenum filter. (author)

  3. New ICRU quantities for the environmental and individual monitoring. Standardization of individual dosemeters by using external beams of photon radiation

    International Nuclear Information System (INIS)

    The quantities introduced by ICRU for the radiological monitoring are commented, specially those implied in individual protection against external photons. A procedure is proposed in order to standardize the individual dosemeters by using the kerma in air references of CIEMAT-JEN. The reference radiation beams are described in connection with ISO standards. Provisional values are selected for the appropriate conversion and correction factors. (Author) 23 refs

  4. Validation testing of ANSI/IEEE n42.49 standard requirements for personal emergency radiation detectors.

    Science.gov (United States)

    Pibida, L; Minniti, R; O'Brien, M

    2010-04-01

    Various radiation detectors including electronic personal emergency radiation detectors (PERDs), radiochromic film cards and thermoluminescent dosimeters (TLDs) were used to validate a subset of the radiological test requirements listed in the American National Standards Institute/The Institute of Electrical and Electronic Engineers (ANSI/IEEE) N42.49 standard. The subset of tests included the following: comparing the readout of the detectors with the value given at the National Institute of Standards and Technology (NIST); testing of the alarm settings (when applicable) in air-kerma (or exposure) and air-kerma rate (or exposure rate) mode; and investigating the effect of testing the detectors mounted on a phantom and free in air. The purpose of this work was not to test the performance of the sample of detectors used. Instead, the detectors were used to validate the requirements of the written standard being developed. For this purpose, the performance and response of these instruments were recorded when placed in (137)Cs, and x-ray beams at different air-kerma rates and test conditions. The measurements described in this report were performed at the NIST x-ray and gamma-ray radiation calibration facilities. The data in this report provide a benchmark in support of the development of the ANSI/IEEE N42.49 standard.

  5. Reduction of air ion mobility to standard conditions

    Science.gov (United States)

    Tammet, H.

    1998-06-01

    The Langevin rule of the reduction of air ion mobility is adequate in case of zero-size ions. An alternative is the Stokes-Millikan equation that is adequate in the limit of macroscopic charged particles. The temperature variation of air ion mobility predicted by the Stokes-Millikan equation radically contradicts the Langevin rule. The temperature and pressure variation of air ion mobility is examined by using a new semiempirical model that describes the transition from the kinetic theory to the Stokes-Millikan equation. The model is valid in full mobility range. It allows to calculate at first the size of an ion according to the measured mobility and then the standard mobility according to the size. The ascent of the temperature-mobility curve on a logarithmic chart approaches the Langevin value of 1 only at very high mobilities not found in the atmosphere. The value of the ascent is 0.6 in the case of small ions of the mobility of 1.5 cm2 V-1 s-1 which brings about a considerable error when using the Langevin rule. It is recommended to store the natural values of the mobility in databases together with the values of temperature and pressure and to definitely indicate the method when the reduced mobilities are presented in publications.

  6. National Emission Standards for Hazardous Air Pollutants submittal -- 1994

    Energy Technology Data Exchange (ETDEWEB)

    Townsend, Y.E. [ed.; Black, S.C.

    1995-06-01

    This report focuses on air quality at the Nevada Test Site (NTS) for 1994. A general description of the effluent sources are presented. Each potential source of NTS emissions was characterized by one of the following: (1) by monitoring methods and procedures previously developed at NTS; (2) by a yearly radionuclide inventory of the source, assuming that volatile radionuclides are released to the environment; (3) by the measurement of tritiated water concentration in liquid effluents discharged to containment ponds and assuming all the effluent evaporates over the course of the year to become an air emission; or (4) by using a combination of environmental measurements and CAP88-PC to calculate emissions. Appendices A through J describe the methods used to determine the emissions from the sources. These National Emission Standards for Hazardous Air Pollutants (NESHAP) emissions are very conservative, are used to calculate the effective dose equivalent to the Maximally Exposed Individual offsite, and exceed, in some cases, those reported in DOE`s Effluent Information System (EIS). The NESHAP`s worst-case emissions that exceed the EIS reported emissions are noted. Offsite environmental surveillance data are used to confirm that calculated emissions are, indeed, conservative.

  7. 78 FR 34964 - Implementation of the 2008 National Ambient Air Quality Standards for Ozone: State Implementation...

    Science.gov (United States)

    2013-06-11

    ... AGENCY 40 CFR Parts 50, 51, 70 and 71 Implementation of the 2008 National Ambient Air Quality Standards... proposed rule ``Implementation of the 2008 National Ambient Air Quality Standards for Ozone: State... proposed rulemaking proposes to implement the 2008 ozone national ambient air quality standards...

  8. 76 FR 54293 - Review of National Ambient Air Quality Standards for Carbon Monoxide

    Science.gov (United States)

    2011-08-31

    ... Ambient Air Quality Standards for Carbon Monoxide; Final Rule #0;#0;Federal Register / Vol. 76 , No. 169..., 53 and 58 RIN 2060-AI43 Review of National Ambient Air Quality Standards for Carbon Monoxide AGENCY... and the national ambient air quality standards (NAAQS) for carbon monoxide (CO). Based on its...

  9. 77 FR 38760 - National Ambient Air Quality Standards for Particulate Matter; Correction

    Science.gov (United States)

    2012-06-29

    ... AGENCY 40 CFR Parts 50, 51, 52, 53, and 58 RIN 2060-AO47 National Ambient Air Quality Standards for... revise the national ambient air quality standards (NAAQS) for particulate matter (PM). This action...: Questions concerning the ``National Ambient Air Quality Standards for Particulate Matter'' proposed...

  10. 78 FR 44485 - Implementation of the 2008 National Ambient Air Quality Standards for Ozone: State Implementation...

    Science.gov (United States)

    2013-07-24

    ... AGENCY 40 CFR Parts 50, 51, 70 and 71 Implementation of the 2008 National Ambient Air Quality Standards... on this rulemaking, contact Dr. Karl Pepple, Office of Air Quality Planning and Standards, U.S... Stackhouse, Office of Air Quality Planning and Standards, U.S. Environmental Protection Agency, by phone...

  11. 78 FR 3085 - National Ambient Air Quality Standards for Particulate Matter

    Science.gov (United States)

    2013-01-15

    ... Air Quality Standards for Particulate Matter; Final Rule #0;#0;Federal Register / Vol. 78 , No. 10..., 51, 52, 53 and 58 RIN 2060-AO47 National Ambient Air Quality Standards for Particulate Matter AGENCY... criteria and the national ambient air quality standards (NAAQS) for particulate matter (PM), the EPA...

  12. Development of a calibration methodology and tests of kerma area product meters; Desenvolvimento de uma metodologia de calibracao e testes de medidores de produto Kerma-Area

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Nathalia Almeida

    2013-07-01

    The quantity kerma area product (PKA) is important to establish reference levels in diagnostic radiology exams. This quantity can be obtained using a PKA meter. The use of such meters is essential to evaluate the radiation dose in radiological procedures and is a good indicator to make sure that the dose limit to the patient's skin doesn't exceed. Sometimes, these meters come fixed to X radiation equipment, which makes its calibration difficult. In this work, it was developed a methodology for calibration of PKA meters. The instrument used for this purpose was the Patient Dose Calibrator (PDC). It was developed to be used as a reference to check the calibration of PKA and air kerma meters that are used for dosimetry in patients and to verify the consistency and behavior of systems of automatic exposure control. Because it is a new equipment, which, in Brazil, is not yet used as reference equipment for calibration, it was also performed the quality control of this equipment with characterization tests, the calibration and an evaluation of the energy dependence. After the tests, it was proved that the PDC can be used as a reference instrument and that the calibration must be performed in situ, so that the characteristics of each X-ray equipment, where the PKA meters are used, are considered. The calibration was then performed with portable PKA meters and in an interventional radiology equipment that has a PKA meter fixed. The results were good and it was proved the need for calibration of these meters and the importance of in situ calibration with a reference meter. (author)

  13. Characterization of a free air ionization chamber for low energies

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Natalia F.; Xavier, Marcos; Vivolo, Vitor; Caldas, Linda V.E., E-mail: nsilva@ipen.br, E-mail: mxavier@ipen.br, E-mail: vivolo@ipen.br, E-mail: lcaldas@ipen.br [Instituto de Pesquisas Energeticas e Nucleres (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    Free air ionization chambers are used by most primary metrology laboratories as primary standards of the quantities air kerma and exposure in X-ray beams. The free air ionization chamber for low energies of the Calibration Laboratory (LCI) of IPEN showed in a characterization test a problem in the set responsible for the variation of its sensitive volume. After a modification in the support of the micrometers used for the movement of the internal cylinder and the establishment of a new alignment system protocol, the tests were redone. The objective of this work was to present the results obtained in the new condition. (author)

  14. Characterization of a free air ionization chamber for low energies

    International Nuclear Information System (INIS)

    Free air ionization chambers are used by most primary metrology laboratories as primary standards of the quantities air kerma and exposure in X-ray beams. The free air ionization chamber for low energies of the Calibration Laboratory (LCI) of IPEN showed in a characterization test a problem in the set responsible for the variation of its sensitive volume. After a modification in the support of the micrometers used for the movement of the internal cylinder and the establishment of a new alignment system protocol, the tests were redone. The objective of this work was to present the results obtained in the new condition. (author)

  15. Information draft on the development of air standards for methanol

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-01-01

    Methanol is a clear, colourless. very mobile liquid with a slightly alcoholic odour in pure form, but a repulsive pungent odour in crude form. Methanol is the raw material in the production of many gasoline additives, is used as a solvent or antifreeze in paint strippers, aerosol spray paints, wall paints, carburetor cleaners, and car windshield washer compounds. Methanol is one of the top pollutants by release quantities in Ontario, the highest release being generated by the pulp and paper industry. Other large emissions come from the plastics and synthetic resin industry. Total release to the air in Canada was 3,668 tonnes in 1996 and the top ten methanol emitting facilities were in Ontario. Methanol is readily absorbed through inhalation, ingestion and skin exposures. Once absorbed, it is oxidized to formaldehyde and then to formic acid. Common symptoms of exposure are visual disturbances, dizziness, nausea, vertigo, pain in the extremities, and headaches. No information was found as to the carcinogenicity of methanol to humans or animals. Current Ontario half-hour POI standard for methanol is 84,000 microgram/cubic meter and the 24-hour AAQC is 28,000 microgram/cubic meter. Both values were established more than 20 years ago. Review of relevant literature, summarized in this report, indicates that five US states have promulgated air quality guidelines or reference exposure levels for methanol, based on occupational exposure limits. The US Environmental Protection Agency is currently reviewing its reference concentration value for methanol. The World Health Organization and the Canadian federal government have not set air quality guidelines for methanol. 37 refs., 1 tab., appendix.

  16. Acidic precipitation: considerations for an air-quality standard

    Energy Technology Data Exchange (ETDEWEB)

    Evans, L.S.; Hendrey, G.R.; Stensland, G.J.; Johnson, D.W.; Francis, A.J.

    1980-01-01

    Acidic precipitation, wet or frozen deposition with a hydrogen ion concentration greatern than 2.5 ..mu..eq l/sup -1/ is a significant air pollution problem in the United States. The chief anions accounting for the hydrogen ions in rainfall are nitrate and sulfate. Agricultural systems are more likely to derive net nutritional benefits from increasing inputs of acidic rain than are forest systems when soils alone are considered. Agricultural soils may benefit because of the high N and S requirements of agricultural plants. Detrimental effects to forest soils may result if atmospheric H/sup +/ inputs significantly add to or exceed H/sup +/ production by soils. Acidification of fresh waters of southern Scandinavia, southwestern Scotland, southeastern Canada, and northeastern United States is caused by acid deposition. Areas of these regions in which this acidification occurs have in common, highly acidic precipitation with volume weighted mean annual H/sup +/ concentrations of 25 ..mu..eq l/sup -1/ or higher and slow weathering granitic or precambrian bedrock with thin soils deficient in minerals which would provide buffer capacity. Biological effects of acidification of fresh waters are detectable below pH 6.0. As lake and stream pH levels decrease below pH. 6.0, many species of plants, invertebrates, and vertebrates are progressively eliminated. Generally, fisheries are impacted below pH 5.0 and are completely destroyed below pH 4.8. There are few studies that document effects of acidic precipitation on terrestrial vegetation to establish an air quality standard. It must be demonstrated that current levels of precipitation acidity alone significantly injure terrestrial vegetation. In terms of documented damanges, current research indicates that establishing a standard for precipitation for the volume weighted annual H/sup +/ concentration at 25 ..mu..eq l/sup -1/ may protect the most sensitive areas from permanent lake acidification.

  17. Project, construction and characterization of ionization chambers for use as standard systems in X and gamma radiation beams

    International Nuclear Information System (INIS)

    Ionization chambers present some advantages in relation to other dosimeters: easiness of handling, low energy dependence and high precision. The advantages associated to ionization chambers and the large number of diagnostic radiology exams and therapeutic treatments motivated the development of this PhD program. In this project ionization chambers were developed and characterized to be applied in diagnostic radiology and therapy beam dosimetry, with high precision and performance, in compliance with international recommendations. They were assembled in a simple way, utilizing low-cost national materials, so they can be reproduced and applied at calibration laboratories. The project of these ionization chambers presents some differences in relation to commercial ionization chambers, as the materials utilized and geometrical arrangements. Besides the development of the ionization chambers to be utilized in standard X-ray beam dosimetry as work standard systems, two graphite parallel-plate ionization chambers were developed and characterized to be applied as reference standard systems for determining the air kerma rates of gamma radiation sources. Comparing the air kerma rates determined with the reference standard of the Calibration Laboratory of IPEN, a Farmer ionization chamber, with the values of the air kerma rates obtained with the graphite ionization chambers, the maximum differences obtained were only 1.7% and 1.2% for the G1 and G2 graphite ionization chambers, respectively. Moreover, these ionization chambers presented correction factors close to 1.000, which is ideal for an ionization chamber be characterized as a reference standard system. (author)

  18. National Emission Standards for Hazardous Air Pollutants Calendar Year 2005

    International Nuclear Information System (INIS)

    The Nevada Test Site (NTS) is operated by the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office (NNSA/NSO). From 1951 through 1992, the NTS was operated as the nation's site for nuclear weapons testing. The release of man-made radionuclides from the NTS as a result of testing activities has been monitored since the first decade of atmospheric testing. After 1962, when nuclear tests were conducted only underground, the radiation exposure to the public surrounding the NTS was greatly reduced. After the 1992 moratorium on nuclear testing, radiation monitoring on the NTS focused on detecting airborne radionuclides that are resuspended into the air (e.g., by winds, dust-devils) along with historically-contaminated soils on the NTS. To protect the public from harmful levels of man-made radiation, the Clean Air Act, National Emission Standards for Hazardous Air Pollutants (NESHAP) (40 Code of Federal Regulations 61 Subpart H) limits the release of radioactivity from a U. S. Department of Energy (DOE) facility (e.g., the NTS) to 10 millirem per year (mrem/yr) effective dose equivalent (EDE) to any member of the public. This is the dose limit established for someone living off of the NTS for inhaling radioactive particles that may be carried by wind off of the NTS. This limit assumes that members of the public surrounding the NTS may also inhale 'background levels' or radioactive particles unrelated to NTS activities that come from naturally-occurring elements in the environment (e.g., radon gas from the earth or natural building materials) or from other man-made sources (e.g., cigarette smoke). The U. S. Environmental Protection Agency (EPA) requires DOE facilities (e.g., the NTS) to demonstrate compliance with the NESHAP dose limit by annually estimating the dose to a hypothetical member of the public, referred to as the maximally exposed individual (MEI), or the member of the public who resides within an 80-kilometer (50-mile) radius

  19. 76 FR 80727 - Flexible Implementation of the Mercury and Air Toxics Standards Rule

    Science.gov (United States)

    2011-12-27

    ... Documents#0;#0; ] Memorandum of December 21, 2011 Flexible Implementation of the Mercury and Air Toxics... the Environmental Protection Agency (EPA), of the final Mercury and Air Toxics Standards rule for... comments, prescribes standards under section 112 of the Clean Air Act to control emissions of mercury...

  20. The role of constitution's standards as the integration part of forming of Ukrainian Air law system

    OpenAIRE

    Шереметьєва, Ольга Юріївна; Інститут повітряного і космічного права та масових комунікацій, Національний авіаційний університет

    2015-01-01

    The role and meaning of constitution's standards as the integration part of forming of Air law system are investigatedat the article and also the status of Ukrainian legislation about the air area using.

  1. 40 CFR 50.17 - National primary ambient air quality standards for sulfur oxides (sulfur dioxide).

    Science.gov (United States)

    2010-07-01

    ... standards for sulfur oxides (sulfur dioxide). 50.17 Section 50.17 Protection of Environment ENVIRONMENTAL....17 National primary ambient air quality standards for sulfur oxides (sulfur dioxide). (a) The level of the national primary 1-hour annual ambient air quality standard for oxides of sulfur is 75...

  2. 76 FR 8157 - National Ambient Air Quality Standards for Carbon Monoxide

    Science.gov (United States)

    2011-02-11

    ... be effectively mitigated by setting more stringent ambient air quality standards (59 FR 38914). Apart... Quality Standards for Carbon Monoxide; Proposed Rule #0;#0;Federal Register / Vol. 76, No. 29 / Friday... National Ambient Air Quality Standards for Carbon Monoxide AGENCY: Environmental Protection Agency...

  3. Evaluation of skin entry kerma in radiological examinations at the Hospital de Clinicas, Parana, Brazil

    International Nuclear Information System (INIS)

    This paper evaluates the skin entry dose of pediatric and adults patients when submitted to radiological examinations at the Hospital de Clinicas do Parana, Brazil, as part integrate of the data assessment of International Atomic Energy Agency (IAEA) for Latin America. It was performed measurements of dose for evaluation of skin entry kerma in pediatric patients in thorax AP/PA examinations, adults of thorax in AP/PA, cranio caudal mammography and median lateral and patients of computerized tomography in examination of head, thorax and abdomen. The obtained data demonstrate the necessity of verification of diagnostic analysis standards. The great value amplitudes demonstrate the incompatibility of examination executions with those recommended by the literature. The dose values presented partially inside the range recommended and the other over the expected for the due examination when compared with the literature

  4. Development of a calibration methodology and tests of kerma area product meters

    International Nuclear Information System (INIS)

    The quantity kerma area product (PKA) is important to establish reference levels in diagnostic radiology exams. This quantity can be obtained using a PKA meter. The use of such meters is essential to evaluate the radiation dose in radiological procedures and is a good indicator to make sure that the dose limit to the patient's skin doesn't exceed. Sometimes, these meters come fixed to X radiation equipment, which makes its calibration difficult. In this work, it was developed a methodology for calibration of PKA meters. The instrument used for this purpose was the Patient Dose Calibrator (PDC). It was developed to be used as a reference to check the calibration of PKA and air kerma meters that are used for dosimetry in patients and to verify the consistency and behavior of systems of automatic exposure control. Because it is a new equipment, which, in Brazil, is not yet used as reference equipment for calibration, it was also performed the quality control of this equipment with characterization tests, the calibration and an evaluation of the energy dependence. After the tests, it was proved that the PDC can be used as a reference instrument and that the calibration must be performed in situ, so that the characteristics of each X-ray equipment, where the PKA meters are used, are considered. The calibration was then performed with portable PKA meters and in an interventional radiology equipment that has a PKA meter fixed. The results were good and it was proved the need for calibration of these meters and the importance of in situ calibration with a reference meter. (author)

  5. The 1997 determination of the Australian standards of exposure and absorbed dose at {sup 60}Co

    Energy Technology Data Exchange (ETDEWEB)

    Huntley, R.B.; Boas, J.F. [Australian Radiation Laboratory, Yallambie, VIC (Australia); Van der Gaast, H. [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia)

    1998-05-01

    The arrangements for the maintenance of the Australian standards for {sup 60}Co are described in detail. The primary standards are a graphite cavity chamber for exposure/air kerma and a graphite calorimeter for absorbed dose. These secondary standards are described and their responses in corresponding {sup 90}Sr reference sources are reported. Accurate ratios between the Australian Radiation Laboratory (ARL) and Australian Nuclear Science and Technology (ANSTO) {sup 90}Sr reference sources are derived for use in future calibrations. The value of 28.8 years for the half-life of {sup 90}Sr is confirmed. The usefulness of {sup 90}Sr reference source measurements in quality assurance is discussed. The charge sensitivity and linearity of the ANSTO electrometers are reported by two different methods and are compared with previous results. Calibration factors for all the secondary standard ionization chambers are given, in terms of exposure, air kerma and absorbed dose to water. Calibration factors are also given for most of the chambers in terms of absorbed dose to graphite. The methods of deriving the calibration factors are explained in detail, including all the corrections applied to both the primary and secondary standard measurements. Three alternative methods of deriving the absorbed dose to water calibration factors are compared. The reported calibration factors are compared with previous results. Changes in the Australian units of exposure, air kerma and absorbed dose to graphite and water are derived from changes in the corresponding calibration factors. The Australian units of exposure and air kerma have not changed significantly since 1990. The Australian unit of absorbed dose to graphite is now 1.1 % smaller than in 1993 and 1.3 % smaller than in 1990. The Australian unit of absorbed dose to water is now 1.4 % smaller than in 1993, but is only 0.9 % smaller than in 1990. Comparisons of the Australian standards of exposure/air kerma and absorbed dose with

  6. Canada-wide standards and innovative transboundary air quality initiatives.

    Science.gov (United States)

    Barton, Jane

    2008-01-01

    Canada's approach to air quality management is one that has brought with it opportunities for the development of unique approaches to risk management. Even with Canada's relatively low levels of pollution, science has demonstrated clearly that air quality and ecosystem improvements are worthwhile. To achieve change and address air quality in Canada, Canadian governments work together since, under the constitution, they share responsibility for the environment. At the same time, because air pollution knows no boundaries, working with the governments of other nations is essential to get results. International cooperation at all levels provides opportunities with potential for real change. Cooperation within transboundary airsheds is proving a fruitful source of innovative opportunities to reduce cross-border barriers to air quality improvements. In relation to the NERAM Colloquium objective to establish principles for air quality management based on the identification of international best practice in air quality policy development and implementation, Canada has developed, both at home and with the United States, interesting air management strategies and initiatives from which certain lessons may be taken that could be useful in other countries with similar situations. In particular, the Canada-wide strategies for smog and acid rain were developed by Canadian governments, strategies that improve and protect air quality at home, while Canada-U.S. transboundary airshed projects provide examples of international initiatives to improve air quality. PMID:18080897

  7. New ICRU quantities for the environmental and individual monitoring. Standardization of individual dosemeters by using external beams of photon radiation; Nuevas magnitudes ICRU para la vigilancia radiologica ambiental e individual. Calibracion de dosimetros personales usando haces externos de fotones

    Energy Technology Data Exchange (ETDEWEB)

    Brosed, A.; Delgado, A.; Granados, C. E.

    1987-07-01

    The quantities introduced by ICRU for the radiological monitoring are commented, specially those implied in individual protection against external photons. A procedure is proposed in order to standardize the individual dosemeters by using the kerma in air references of CIEMAT-JEN. The reference radiation beams are described in connection with ISO standards. Provisional values are selected for the appropriate conversion and correction factors. (Author) 23 refs.

  8. A proposed risk management framework for the air standard setting process in Ontario : a discussion paper

    International Nuclear Information System (INIS)

    This paper described the implementation of Ontario's new or revised air quality standards relating to Ontario Regulation 346 under the Environmental Protection Act. With clean air as a high priority, the Ontario Ministry of the Environment is striving to find solutions to problems that pose the greatest risk to human health and the environment. Their most recent initiatives in the development of better air quality standards have included the use of the latest scientific information to develop protective, effects-based air standards and the development of a risk management framework to implement the new standards while allowing for time, technology and economic issues to be considered. An update of Regulation 346 air dispersion models ensures that the latest scientific tools are being used to asses compliance with air standards. The phasing out of the existing air dispersion models means that they will be replaced by a series of models from the United States Environmental Protection Agency (in particular AERMOD and ISC-PRIME). This will promote the use of the most modern scientific tools available to assess compliance with air quality standards. The major advantage of introducing new air dispersion models is the ability to use effects-based standards with appropriate averaging times to assess compliance. This makes it possible to better assess the health and environmental impacts from air emissions. 3 tabs., 3 figs

  9. The role of Health Impact Assessment in the setting of air quality standards: An Australian perspective

    Energy Technology Data Exchange (ETDEWEB)

    Spickett, Jeffery, E-mail: J.Spickett@curtin.edu.au [WHO Collaborating Centre for Environmental Health Impact Assessment (Australia); Faculty of Health Sciences, School of Public Health, Curtin University, Perth, Western Australia (Australia); Katscherian, Dianne [WHO Collaborating Centre for Environmental Health Impact Assessment (Australia); Faculty of Health Sciences, School of Public Health, Curtin University, Perth, Western Australia (Australia); Harris, Patrick [CHETRE — UNSW Research Centre for Primary Health Care and Equity, University of New South Wales (Australia)

    2013-11-15

    The approaches used for setting or reviewing air quality standards vary from country to country. The purpose of this research was to consider the potential to improve decision-making through integration of HIA into the processes to review and set air quality standards used in Australia. To assess the value of HIA in this policy process, its strengths and weaknesses were evaluated aligned with review of international processes for setting air quality standards. Air quality standard setting programmes elsewhere have either used HIA or have amalgamated and incorporated factors normally found within HIA frameworks. They clearly demonstrate the value of a formalised HIA process for setting air quality standards in Australia. The following elements should be taken into consideration when using HIA in standard setting. (a) The adequacy of a mainly technical approach in current standard setting procedures to consider social determinants of health. (b) The importance of risk assessment criteria and information within the HIA process. The assessment of risk should consider equity, the distribution of variations in air quality in different locations and the potential impacts on health. (c) The uncertainties in extrapolating evidence from one population to another or to subpopulations, especially the more vulnerable, due to differing environmental factors and population variables. (d) The significance of communication with all potential stakeholders on issues associated with the management of air quality. In Australia there is also an opportunity for HIA to be used in conjunction with the NEPM to develop local air quality standard measures. The outcomes of this research indicated that the use of HIA for air quality standard setting at the national and local levels would prove advantageous. -- Highlights: • Health Impact Assessment framework has been applied to a policy development process. • HIA process was evaluated for application in air quality standard setting.

  10. Characterization of a free air ionization chamber for low energy X-rays

    Science.gov (United States)

    Silva, N. F.; Xavier, M.; Vivolo, V.; Caldas, L. V. E.

    2016-07-01

    Free air ionization chambers are used by most primary metrology laboratories as primary standards of the quantities air kerma and exposure in X-ray beams. The free air ionization chamber for low energies of the Calibration Laboratory (LCI) of IPEN showed in a characterization test a problem in the set responsible for the variation of its sensitive volume. After a modification in the support of the micrometers used for the movement of the internal cylinder and the establishment of a new alignment system protocol, the tests were redone. The objective of this work was to present the results obtained in the new condition.

  11. 76 FR 74708 - National Emission Standards for Hazardous Air Pollutants for Source Categories

    Science.gov (United States)

    2011-12-01

    ... AGENCY 40 CFR Part 63 National Emission Standards for Hazardous Air Pollutants for Source Categories CFR... means mineral wool to which a hazardous air pollutant-based binder (containing such hazardous air pollutants as phenol or formaldehyde) has been applied. CO means, for the purposes of this subpart,...

  12. 49 CFR 571.121 - Standard No. 121; Air brake systems.

    Science.gov (United States)

    2010-10-01

    ... Motor Vehicle Safety Standards § 571.121 Standard No. 121; Air brake systems. S1. Scope. This standard... emergency conditions. S3. Application. This standard applies to trucks, buses, and trailers equipped with... definition of heavy hauler trailer set forth in S4; (f) Any trailer that has an unloaded vehicle weight...

  13. 77 FR 39205 - Public Hearings for Proposed Rules-National Ambient Air Quality Standards for Particulate Matter

    Science.gov (United States)

    2012-07-02

    ... Quality Standards for Particulate Matter AGENCY: Environmental Protection Agency (EPA). ACTION... titled, ``National Ambient Air Quality Standards for Particulate Matter,'' that is scheduled to be... and secondary national ambient air quality standards (NAAQS) for particulate matter (PM) to...

  14. 40 CFR 50.5 - National secondary ambient air quality standard for sulfur oxides (sulfur dioxide).

    Science.gov (United States)

    2010-07-01

    ... standard for sulfur oxides (sulfur dioxide). 50.5 Section 50.5 Protection of Environment ENVIRONMENTAL....5 National secondary ambient air quality standard for sulfur oxides (sulfur dioxide). (a) The level... than 0.05 ppm shall be rounded up). (b) Sulfur oxides shall be measured in the ambient air as...

  15. 77 FR 2677 - National Emission Standards for Hazardous Air Pollutants: Primary Aluminum Reduction Plants...

    Science.gov (United States)

    2012-01-19

    ... Standards for Hazardous Air Pollutants: Primary Aluminum Reduction Plants'' is being extended for 12 days. DATES: Comments. The public comment period for the proposed rule published December 6, 2011, (76 FR... AGENCY 40 CFR Part 63 RIN 2060-AQ-92 National Emission Standards for Hazardous Air Pollutants:...

  16. 77 FR 41146 - Delegation of National Emission Standards for Hazardous Air Pollutants for Source Categories...

    Science.gov (United States)

    2012-07-12

    ... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 63 Delegation of National Emission Standards for Hazardous Air Pollutants for Source... delegation of specific national emission standards for hazardous air pollutants (NESHAP) to the Gila...

  17. 76 FR 38591 - National Emission Standards for Hazardous Air Pollutants: Secondary Lead Smelting; Extension of...

    Science.gov (United States)

    2011-07-01

    ... the National Emissions Standards for Hazardous Air Pollutants for Secondary Lead Smelting (76 FR 29032... Standards for Hazardous Air Pollutants: Secondary Lead Smelting, was published May 19, 2011 (76 FR 29032... current rule. DATES: Comments on the proposed rule published May 19, 2011 (76 FR 29032) must be...

  18. 40 CFR 50.9 - National 1-hour primary and secondary ambient air quality standards for ozone.

    Science.gov (United States)

    2010-07-01

    ... ambient air quality standards for ozone. 50.9 Section 50.9 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS NATIONAL PRIMARY AND SECONDARY AMBIENT AIR QUALITY STANDARDS § 50.9 National 1-hour primary and secondary ambient air quality standards for ozone. (a) The level...

  19. 76 FR 76972 - Release of Final Integrated Review Plan for the National Ambient Air Quality Standards for Lead

    Science.gov (United States)

    2011-12-09

    ... AGENCY Release of Final Integrated Review Plan for the National Ambient Air Quality Standards for Lead... the National Ambient Air Quality Standards for Lead. This document contains the plans for the review of the air quality criteria and national ambient air quality standards (NAAQS) for lead (Pb). The...

  20. 76 FR 20347 - Release of Draft Integrated Review Plan for the National Ambient Air Quality Standards for Lead

    Science.gov (United States)

    2011-04-12

    ... AGENCY Release of Draft Integrated Review Plan for the National Ambient Air Quality Standards for Lead... National Ambient Air Quality Standards for Lead (draft IRP). This document contains the plans for the review of the air quality criteria and national ambient air quality standards (NAAQS) for lead (Pb)....

  1. 40 CFR 50.7 - National primary and secondary ambient air quality standards for PM2.5.

    Science.gov (United States)

    2010-07-01

    ... air quality standards for PM2.5. 50.7 Section 50.7 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS NATIONAL PRIMARY AND SECONDARY AMBIENT AIR QUALITY STANDARDS § 50.7 National primary and secondary ambient air quality standards for PM2.5. (a) The national primary...

  2. 40 CFR Appendix R to Part 50 - Interpretation of the National Ambient Air Quality Standards for Lead

    Science.gov (United States)

    2010-07-01

    ... Air Quality Standards for Lead R Appendix R to Part 50 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS NATIONAL PRIMARY AND SECONDARY AMBIENT AIR QUALITY STANDARDS Pt. 50, App. R Appendix R to Part 50—Interpretation of the National Ambient Air Quality Standards...

  3. 40 CFR 50.10 - National 8-hour primary and secondary ambient air quality standards for ozone.

    Science.gov (United States)

    2010-07-01

    ... ambient air quality standards for ozone. 50.10 Section 50.10 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS NATIONAL PRIMARY AND SECONDARY AMBIENT AIR QUALITY STANDARDS § 50.10 National 8-hour primary and secondary ambient air quality standards for ozone. (a) The level...

  4. 40 CFR Appendix P to Part 50 - Interpretation of the Primary and Secondary National Ambient Air Quality Standards for Ozone

    Science.gov (United States)

    2010-07-01

    ... Secondary National Ambient Air Quality Standards for Ozone P Appendix P to Part 50 Protection of Environment... Air Quality Standards for Ozone 1. General (a) This appendix explains the data handling conventions... air quality standards for ozone (O3) specified in § 50.15 are met at an ambient O3 air...

  5. 40 CFR 50.13 - National primary and secondary ambient air quality standards for PM2.5.

    Science.gov (United States)

    2010-07-01

    ... air quality standards for PM2.5. 50.13 Section 50.13 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS NATIONAL PRIMARY AND SECONDARY AMBIENT AIR QUALITY STANDARDS § 50.13 National primary and secondary ambient air quality standards for PM2.5. (a) The national...

  6. 40 CFR Appendix N to Part 50 - Interpretation of the National Ambient Air Quality Standards for PM2.5

    Science.gov (United States)

    2010-07-01

    ... Air Quality Standards for PM2.5 N Appendix N to Part 50 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS NATIONAL PRIMARY AND SECONDARY AMBIENT AIR QUALITY STANDARDS Pt. 50, App. N Appendix N to Part 50—Interpretation of the National Ambient Air Quality Standards for...

  7. Project, construction and characterization of ionization chambers for use as standard systems in X and gamma radiation beams; Projeto, construcao e caracterizacao de camaras de ionizacao para utilizacao como sistemas padroes em feixes de radiacao X e gama

    Energy Technology Data Exchange (ETDEWEB)

    Perini, Ana Paula

    2013-07-01

    Ionization chambers present some advantages in relation to other dosimeters: easiness of handling, low energy dependence and high precision. The advantages associated to ionization chambers and the large number of diagnostic radiology exams and therapeutic treatments motivated the development of this PhD program. In this project ionization chambers were developed and characterized to be applied in diagnostic radiology and therapy beam dosimetry, with high precision and performance, in compliance with international recommendations. They were assembled in a simple way, utilizing low-cost national materials, so they can be reproduced and applied at calibration laboratories. The project of these ionization chambers presents some differences in relation to commercial ionization chambers, as the materials utilized and geometrical arrangements. Besides the development of the ionization chambers to be utilized in standard X-ray beam dosimetry as work standard systems, two graphite parallel-plate ionization chambers were developed and characterized to be applied as reference standard systems for determining the air kerma rates of gamma radiation sources. Comparing the air kerma rates determined with the reference standard of the Calibration Laboratory of IPEN, a Farmer ionization chamber, with the values of the air kerma rates obtained with the graphite ionization chambers, the maximum differences obtained were only 1.7% and 1.2% for the G1 and G2 graphite ionization chambers, respectively. Moreover, these ionization chambers presented correction factors close to 1.000, which is ideal for an ionization chamber be characterized as a reference standard system. (author)

  8. Secondary bremsstrahlung and the energy-conservation aspects of kerma in photon-irradiated media

    Science.gov (United States)

    Kumar, Sudhir; Nahum, Alan E.

    2016-02-01

    Kerma, collision kerma and absorbed dose in media irradiated by megavoltage photons are analysed with respect to energy conservation. The user-code DOSRZnrc was employed to compute absorbed dose D, kerma K and a special form of kerma, K ncpt, obtained by setting the charged-particle transport energy cut-off very high, thereby preventing the generation of ‘secondary bremsstrahlung’ along the charged-particle paths. The user-code FLURZnrc was employed to compute photon fluence, differential in energy, from which collision kerma, K col and K were derived. The ratios K/D, K ncpt/D and K col/D have thereby been determined over a very large volumes of water, aluminium and copper irradiated by broad, parallel beams of 0.1 to 25 MeV monoenergetic photons, and 6, 10 and 15 MV ‘clinical’ radiotherapy qualities. Concerning depth-dependence, the ‘area under the kerma, K, curve’ exceeded that under the dose curve, demonstrating that kerma does not conserve energy when computed over a large volume. This is due to the ‘double counting’ of the energy of the secondary bremsstrahlung photons, this energy being (implicitly) included in the kerma ‘liberated’ in the irradiated medium, at the same time as this secondary bremsstrahlung is included in the photon fluence which gives rise to kerma elsewhere in the medium. For 25 MeV photons this ‘violation’ amounts to 8.6%, 14.2% and 25.5% in large volumes of water, aluminium and copper respectively but only 0.6% for a ‘clinical’ 6 MV beam in water. By contrast, K col/D and K ncpt/D, also computed over very large phantoms of the same three media, for the same beam qualities, are equal to unity within (very low) statistical uncertainties, demonstrating that collision kerma and the special type of kerma, K ncpt, do conserve energy over a large volume. A comparison of photon fluence spectra for the 25 MeV beam at a depth of  ≈51 g cm-2 for both very high and very low charged-particle transport cut

  9. Heating, Air-Conditioning, and Refrigeration Technician. National Skill Standards.

    Science.gov (United States)

    Vocational Technical Education Consortium of States, Decatur, GA.

    This guide contains information on the knowledge and skills identified by industry as essential to the job performance of heating, air-conditioning, and refrigeration technicians. It is intended to assist training providers in public and private institutions, as well as in industry, to develop and implement training that will provide workers with…

  10. Dosimetry and kVp standardization for quality assurance of mammography

    International Nuclear Information System (INIS)

    Breast cancer mortality rates were significantly reduced in Taiwan after achieving early-stage monitoring with mammography screening. This study establishes an appropriate and traceable calibration infrastructure, which offers calibration services for mammography X-ray quality assurance instrumentation, which is performed clinically on a regular basis. The entrance air kerma, HVL, and kVp of mammography equipment with five different target/filter combinations can be taken as adequate indicators for the level of average glandular dose (AGD). The primary dose standard in mammography uses a free-air ionization chamber to estimate the rate of air kerma. Several correction factors were determined by Monte Carlo simulations and experiments. A secondary kVp standard in mammography is in accordance with the IEC 61676 recommendations. The calibration system of kVp meter uses a high-voltage divider, which is traceable to ITRI primary standard in Taiwan. Dose and kVp verifications were conducted by mammography instruments, which were previously calibrated by NIST and PTB. The evaluation results indicate that the capabilities of this irradiation system met the ISO 4037-1 requirements. The expanded uncertainties (k=2) were 1.03% and 1.6% when the mammography X-ray air kerma rate and kVp meter calibration factors were evaluated using ISO GUM. Experimental verification and a comparison with NIST using transfer ionization chambers yielded differences in calibration factors. Comparison with the PTB using kVp meter indicated a less than 1% difference. The results showed that dose and kVp standards were in reasonable agreement with standard uncertainty. The low uncertainties associated with the obtained results in this work show that the standardization employed can be accurately used for calibration of instrument in mammography in Taiwan. - Highlights: • We established calibration infrastructure for mammography X-ray quality assurance. • The expanded uncertainty of calibration

  11. National Emission Standards for Hazardous Air Pollutants Calendar Year 2006

    Energy Technology Data Exchange (ETDEWEB)

    NSTec Environmental Technical Services

    2007-06-01

    The Nevada Test Site (NTS) is operated by the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office (NNSA/NSO). From 1951 through 1992, the NTS was operated as the nation's site for nuclear weapons testing. The release of man-made radionuclides from the NTS as a result of testing activities has been monitored since the first decade of atmospheric testing. After 1962, when nuclear tests were conducted only underground, the radiation exposure to the public surrounding the NTS was greatly reduced. After the 1992 moratorium on nuclear testing, radiation monitoring on the NTS focused on detecting airborne radionuclides which come from historically-contaminated soils resuspended into the air (e.g., by winds) and tritium-contaminated soil moisture emitted to the air from soils through evapotranspiration.

  12. 76 FR 21692 - National Emission Standards for Hazardous Air Pollutants: Primary Lead Smelting

    Science.gov (United States)

    2011-04-18

    ... Air Pollutants for Primary Lead Smelting (76 FR 9410). The EPA is extending the deadline for written... Pollutants: Primary Lead Smelting, was published February 17, 2011 (76 FR 9410). EPA has established the... AGENCY 40 CFR Part 63 RIN 2060-AQ43 National Emission Standards for Hazardous Air Pollutants:...

  13. 77 FR 11476 - Delegation of National Emission Standards for Hazardous Air Pollutants for Source Categories; Nevada

    Science.gov (United States)

    2012-02-27

    ... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 63 Delegation of National Emission Standards for Hazardous Air Pollutants for Source... for hazardous air pollutants (NESHAP) to the Nevada Division of Environmental Protection on October...

  14. 77 FR 1267 - National Emission Standards for Hazardous Air Pollutant Emissions: Group IV Polymers and Resins...

    Science.gov (United States)

    2012-01-09

    ... Polymers and Resins were promulgated on September 12, 1996 (61 FR 48208), and codified at 40 CFR part 63... Hazardous Air Pollutant Emissions: Group IV Polymers and Resins; Pesticide Active Ingredient Production; and... Emission Standards for Hazardous Air Pollutant Emissions: Group IV Polymers and Resins; Pesticide...

  15. 76 FR 29527 - National Emission Standards for Hazardous Air Pollutants for Polyvinyl Chloride and Copolymers...

    Science.gov (United States)

    2011-05-20

    ... Hazardous Air Pollutants for Polyvinyl Chloride and Copolymers Production; Proposed Rule #0;#0;Federal.... SUMMARY: EPA is proposing National Emission Standards for Hazardous Air Pollutants for Polyvinyl Chloride... pollutants from polyvinyl chloride and copolymers production located at major and area sources. The...

  16. 40 CFR 50.11 - National primary and secondary ambient air quality standards for oxides of nitrogen (with...

    Science.gov (United States)

    2010-07-01

    ... air quality standards for oxides of nitrogen (with nitrogen dioxide as the indicator). 50.11 Section... PRIMARY AND SECONDARY AMBIENT AIR QUALITY STANDARDS § 50.11 National primary and secondary ambient air quality standards for oxides of nitrogen (with nitrogen dioxide as the indicator). (a) The level of...

  17. 77 FR 51798 - First Draft Documents Related to the Review of the National Ambient Air Quality Standards for Ozone

    Science.gov (United States)

    2012-08-27

    ... AGENCY First Draft Documents Related to the Review of the National Ambient Air Quality Standards for... of the Ozone National Ambient Air Quality Standards: First External Review Draft. The Agency is...-001; July 2012), please contact Ms. Karen Wesson, Office of Air Quality Planning and Standards...

  18. 75 FR 16459 - Draft Document Related to the Review of the National Ambient Air Quality Standards for...

    Science.gov (United States)

    2010-04-01

    ... AGENCY Draft Document Related to the Review of the National Ambient Air Quality Standards for Particulate... titled, Policy Assessment for the Review of the Particulate Matter National Ambient Air Quality Standards... Particulate Matter National Ambient Air Quality Standards--First External Review Draft (March 2010),...

  19. Environmental Monitoring, Air Quality - MO 2011 Air Quality Standards Nonattainment Areas (SHP)

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — The St. Louis air quality nonattainment areas geospatial data layer contains regions representing the geographic extent of areas that are estimated to be out of...

  20. National Emission Standards for Hazardous Air Pollutants, June 2005

    Energy Technology Data Exchange (ETDEWEB)

    Robert F. Grossman

    2005-06-01

    The sources of radionuclides include current and previous activities conducted on the NTS. The NTS was the primary location for testing of nuclear explosives in the Continental U.S. between 1951 and 1992. Historical testing has included (1) atmospheric testing in the 1950s and early 1960s, (2) underground testing between 1951 and 1992, and (3) open-air nuclear reactor and rocket engine testing (DOE, 1996a). No nuclear tests have been conducted since September 23,1992 (DOE, 2000), however; radionuclides remaining on the soil surface in many NTS areas after several decades of radioactive decay are re-suspended into the atmosphere at concentrations that can be detected by air sampling. Limited non-nuclear testing includes spills of hazardous materials at the Non-Proliferation Test and Evaluation Complex (formerly called the Hazardous Materials Spill Center), private technology development, aerospace and demilitarization activities, and site remediating activities. Processing of radioactive materials is limited to laboratory analyses; handling, transport, storage, and assembly of nuclear explosive devices or radioactive targets for the Joint Actinide Shock Physics Experimental Research (JASPER) gas gun; and operation of radioactive waste management sites (RWMSs) for low-level radioactive and mixed waste (DOE, 1996a). Monitoring and evaluation of the various activities conducted onsite indicate that the potential sources of offsite radiation exposure in calendar year (CY) 2004 were releases from (1) evaporation of tritiated water (HTO) from containment ponds that receive drainage water from E Tunnel in Area 12 and water pumped from wells used to characterize the aquifers at the sites of past underground nuclear tests, (2) onsite radioanalytical laboratories, (3) the Area 3 and Area 5 RWMS facilities, and (4) diffuse sources of tritium (H{sup 3}) and re-suspension of plutonium ({sup 239+240}Pu) and americium ({sup 241}Am) at the sites of past nuclear tests. The following

  1. Laboratory Evaluation of Air Flow Measurement Methods for Residential HVAC Returns for New Instrument Standards

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Iain [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Stratton, Chris [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2015-08-01

    This project improved the accuracy of air flow measurements used in commissioning California heating and air conditioning systems in Title 24 (Building and Appliance Efficiency Standards), thereby improving system performance and efficiency of California residences. The research team at Lawrence Berkeley National Laboratory addressed the issue that typical tools used by contractors in the field to test air flows may not be accurate enough to measure return flows used in Title 24 applications. The team developed guidance on performance of current diagnostics as well as a draft test method for use in future evaluations. The study team prepared a draft test method through ASTM International to determine the uncertainty of air flow measurements at residential heating ventilation and air conditioning returns and other terminals. This test method, when finalized, can be used by the Energy Commission and other entities to specify required accuracy of measurement devices used to show compliance with standards.

  2. Standards for securing adequate indoor air quality across Europe

    DEFF Research Database (Denmark)

    Wargocki, Pawel; Carrer, P.; de Oliveira Fernandes, E.;

    2013-01-01

    of diseases and mortality was used in risk analysis. Ventilation rate was defined as volume of fresh air introduced into the space per person (L/sp). Results: The data in the reviewed studies on ventilation and health were found inadequate to set the health-based ventilation rates mainly because the studies...... sources of pollution. Ventilation is one of many factors determining IAQ. The aim of DG SANCO funded HealthVent project was to assess how ventilation should be defined in terms of achieving conditions for securing health. Methods: Review of the available literature was made so as to break down the health...... to be efficient. As a consequence HealthVent proposed that source control is a key strategy for IAQ and that ventilation should be an ultimate measure. HealthVent defined the minimum reference ventilation rate to reduce risk of health to be set at 4 L/s per person. This rate is only to handle human bioeffluents...

  3. National Emission Standards for Hazardous Air Pollutants Submittal - 1998; TOPICAL

    International Nuclear Information System (INIS)

    The Nevada Test Site (NTS) is operated by the U.S. Department of Energy Nevada Operations Office (DOE/NV) as the site for nuclear weapons testing, now limited to readiness activities and experiments in support of the national Stockpile Stewardship Management Program. It is located in Nye County, Nevada, with the southeast corner about 105 km (65 mi) northwest of Las Vegas, Nevada. The NTS covers about 3,500 km2 (1,350 mi2), an area larger than Rhode Island. Its size is about 46 to 56 km (28 to 35 mi) east to west and from 64 to 88 km (40 to 55 mi)north to south. The NTS is surrounded, except on the south side, by public exclusion areas (Nellis Air Force Range) that provide another 24 to 104 km (15 to 65 mi) between the NTS and public lands. The NTS is characterized by desert valley and Great Basin mountain topography, with a climate, flora, and fauna typical of the southwest deserts. Surface waters are scarce on the NTS and there is great depth to slow-moving groundwater

  4. National Emission Standards for Hazardous Air Pollutants Calendar Year 2001

    International Nuclear Information System (INIS)

    The Nevada Test Site (NTS) is operated by the U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Operations Office (NNSA/NV) as the site for nuclear weapons testing, now limited to readiness activities, experiments in support of the national Stockpile Stewardship Program, and the activities listed below. Located in Nye County, Nevada, the site's southeast corner is about 88 km (55 mi) northwest of the major population center, Las Vegas, Nevada. The NTS covers about 3,561 km2 (1,375 mi2), an area larger than Rhode Island. Its size is 46 to 56 km (28 to 35 mi) east to west and from 64 to 88 km (40 to 55 mi) north to south. The NTS is surrounded, except on the south side, by public exclusion areas (Nellis Air Force Range [NAFR]) that provide another 24 to 104 km (15 to 65 mi) between the NTS and public lands (Figure 1.0). The NTS is characterized by desert valley and Great Basin mountain topography, with a climate, flora, and fauna typical of the southwest deserts. Population density within 150 km (93 mi) of the NTS is only about 0.2 persons per square kilometer, excluding the Las Vegas area. Restricted access, low population density in the surrounding area, and extended wind transport times are advantageous factors for the activities conducted at the NTS. Surface waters are scarce on the NTS, and slow-moving groundwater is present hundreds to thousands of feet below the land surface. The sources of radionuclides include current and previous activities conducted on the NTS (Figure 2.0). The NTS was the primary location for testing of nuclear explosives in the Continental U.S. between 1951 and 1992. Historical testing above or at ground surface has included (1) atmospheric testing in the 1950s and early 1960s, (2) earth-cratering experiments, and (3) open-air nuclear reactor and rocket engine testing. Since the mid-1950s, testing of nuclear explosive devices has occurred underground in drilled vertical holes or in mined tunnels (DOE 1996a

  5. National Emission Standards for Hazardous Air Pollutants Calendar Year 2001

    Energy Technology Data Exchange (ETDEWEB)

    Y. E. Townsend

    2002-06-01

    The Nevada Test Site (NTS) is operated by the U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Operations Office (NNSA/NV) as the site for nuclear weapons testing, now limited to readiness activities, experiments in support of the national Stockpile Stewardship Program, and the activities listed below. Located in Nye County, Nevada, the site's southeast corner is about 88 km (55 mi) northwest of the major population center, Las Vegas, Nevada. The NTS covers about 3,561 km2 (1,375 mi2), an area larger than Rhode Island. Its size is 46 to 56 km (28 to 35 mi) east to west and from 64 to 88 km (40 to 55 mi) north to south. The NTS is surrounded, except on the south side, by public exclusion areas (Nellis Air Force Range [NAFR]) that provide another 24 to 104 km (15 to 65 mi) between the NTS and public lands (Figure 1.0). The NTS is characterized by desert valley and Great Basin mountain topography, with a climate, flora, and fauna typical of the southwest deserts. Population density within 150 km (93 mi) of the NTS is only about 0.2 persons per square kilometer, excluding the Las Vegas area. Restricted access, low population density in the surrounding area, and extended wind transport times are advantageous factors for the activities conducted at the NTS. Surface waters are scarce on the NTS, and slow-moving groundwater is present hundreds to thousands of feet below the land surface. The sources of radionuclides include current and previous activities conducted on the NTS (Figure 2.0). The NTS was the primary location for testing of nuclear explosives in the Continental U.S. between 1951 and 1992. Historical testing above or at ground surface has included (1) atmospheric testing in the 1950s and early 1960s, (2) earth-cratering experiments, and (3) open-air nuclear reactor and rocket engine testing. Since the mid-1950s, testing of nuclear explosive devices has occurred underground in drilled vertical holes or in mined tunnels (DOE

  6. Source geometry factors for HDR 192Ir brachytherapy secondary standard well-type ionization chamber calibrations

    Science.gov (United States)

    Shipley, D. R.; Sander, T.; Nutbrown, R. F.

    2015-03-01

    Well-type ionization chambers are used for measuring the source strength of radioactive brachytherapy sources before clinical use. Initially, the well chambers are calibrated against a suitable national standard. For high dose rate (HDR) 192Ir, this calibration is usually a two-step process. Firstly, the calibration source is traceably calibrated against an air kerma primary standard in terms of either reference air kerma rate or air kerma strength. The calibrated 192Ir source is then used to calibrate the secondary standard well-type ionization chamber. Calibration laboratories are usually only equipped with one type of HDR 192Ir source. If the clinical source type is different from that used for the calibration of the well chamber at the standards laboratory, a source geometry factor, ksg, is required to correct the calibration coefficient for any change of the well chamber response due to geometric differences between the sources. In this work we present source geometry factors for six different HDR 192Ir brachytherapy sources which have been determined using Monte Carlo techniques for a specific ionization chamber, the Standard Imaging HDR 1000 Plus well chamber with a type 70010 HDR iridium source holder. The calculated correction factors were normalized to the old and new type of calibration source used at the National Physical Laboratory. With the old Nucletron microSelectron-v1 (classic) HDR 192Ir calibration source, ksg was found to be in the range 0.983 to 0.999 and with the new Isodose Control HDR 192Ir Flexisource ksg was found to be in the range 0.987 to 1.004 with a relative uncertainty of 0.4% (k = 2). Source geometry factors for different combinations of calibration sources, clinical sources, well chambers and associated source holders, can be calculated with the formalism discussed in this paper.

  7. 40 CFR Appendix K to Part 50 - Interpretation of the National Ambient Air Quality Standards for Particulate Matter

    Science.gov (United States)

    2010-07-01

    ... Air Quality Standards for Particulate Matter K Appendix K to Part 50 Protection of Environment... STANDARDS Pt. 50, App. K Appendix K to Part 50—Interpretation of the National Ambient Air Quality Standards... particulate matter data to determine attainment of the 24-hour standards specified in 40 CFR 50.6. For...

  8. 76 FR 80261 - National Emission Standards for Hazardous Air Pollutants: Area Source Standards for Prepared...

    Science.gov (United States)

    2011-12-23

    ... Air Pollutant (HAP) emissions control (75 FR 533). We added the 95-percent design efficiency... published on January 5, 2010, (75 FR 522) if adverse comments are received on this direct final rule. If we.... V. What amendments are being made to this rule? On January 5, 2010 (75 FR 522), the EPA...

  9. 75 FR 71033 - Air Quality Designations for the 2008 Lead (Pb) National Ambient Air Quality Standards

    Science.gov (United States)

    2010-11-22

    ... Linden (215) 814-2096, Region IV--Lynorae Benjamin (404) 562-9040, Region V--Andy Chang (312) 886-0258.... 2023, (617) 918-1661. Raymond Werner, Chief, Air Programs New Jersey, New York, Puerto Branch, EPA... Agency FR Federal Register FRM Federal Reference Method IQ Intelligence Quotient NAAQS National...

  10. 76 FR 72097 - Air Quality Designations for the 2008 Lead (Pb) National Ambient Air Quality Standards

    Science.gov (United States)

    2011-11-22

    ..., Region 3--Melissa Linden (215) 814-2096, Region 4--Steve Scofield (404) 562-9034, Region 5--Andy Chang..., Boston, MA 02114- Rhode Island, and Vermont. 2023, (617) 918-1661. Raymond Werner, Chief, Air Programs... Environmental Protection Agency FR Federal Register FEM Federal Equivalent Method FRM Federal Reference...

  11. Design and preliminary test of a free-air ionization chamber for low-energy X-ray

    Institute of Scientific and Technical Information of China (English)

    WU Jin-Jie; YANG Yuan-Di; WANG Pei-Wei; CHEN Jing; LIU Jia-Cheng

    2011-01-01

    A free-air ionization chamber in low-energy X-ray has been designed and manufactured at theNational Institute of Metrology (NIM, China) according to the defination of alr-kerma. The results of a preliminary test show that the leakage current of ionization chamber is around 2×10A, and the correction factor of ion recombination for the ionization chamber is also obtained. The free-air ionization chamber is suitable for the primary standard in low-energy X-rays.

  12. Evaluation of skin entry kerma in radiological examinations at the Hospital de Clinicas, Parana, Brazil; Avaliacao de kerma de entrada na pele em exames radiologicos no Hospital de Clinicas do Parana, Brasil

    Energy Technology Data Exchange (ETDEWEB)

    Porto, Lorena E.; Schelin, Hugo R.; Santos, Amanda C. dos; Bunick, Ana Paula; Paschuk, Sergei; Denyak, Valeriy [Universidade Tecnologica Federal do Parana (UTFPR), Curitiba, PR (Brazil); Tilly Junior, Joao G. [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Hospital de Clinicas; Khoury, Helen J., E-mail: khoury@ufpe.b [Universidade Federal de Pernambuco (UFPE/DEN), Recife, PE (Brazil). Dept. de Energia Nuclear

    2011-10-26

    This paper evaluates the skin entry dose of pediatric and adults patients when submitted to radiological examinations at the Hospital de Clinicas do Parana, Brazil, as part integrate of the data assessment of International Atomic Energy Agency (IAEA) for Latin America. It was performed measurements of dose for evaluation of skin entry kerma in pediatric patients in thorax AP/PA examinations, adults of thorax in AP/PA, cranio caudal mammography and median lateral and patients of computerized tomography in examination of head, thorax and abdomen. The obtained data demonstrate the necessity of verification of diagnostic analysis standards. The great value amplitudes demonstrate the incompatibility of examination executions with those recommended by the literature. The dose values presented partially inside the range recommended and the other over the expected for the due examination when compared with the literature

  13. 75 FR 67361 - Release of Final Document Related to the Review of the National Ambient Air Quality Standards for...

    Science.gov (United States)

    2010-11-02

    ... final document titled Policy Assessment for the Review of the Carbon Monoxide National Ambient Air... the Plan for Review of the National Ambient Air Quality Standards for Carbon Monoxide (EPA 452R-08-005... AGENCY Release of Final Document Related to the Review of the National Ambient Air Quality Standards...

  14. 40 CFR Appendix S to Part 50 - Interpretation of the Primary National Ambient Air Quality Standards for Oxides of Nitrogen...

    Science.gov (United States)

    2010-07-01

    ... Ambient Air Quality Standards for Oxides of Nitrogen (Nitrogen Dioxide) S Appendix S to Part 50 Protection... SECONDARY AMBIENT AIR QUALITY STANDARDS Pt. 50, App. S Appendix S to Part 50—Interpretation of the Primary... be submitted to EPA's Air Quality System (AQS), or otherwise available to EPA, meeting...

  15. IMT-2000 Satellite Standards with Applications to Mobile Air Traffic Communications Networks

    Science.gov (United States)

    Shamma, Mohammed A.

    2004-01-01

    The International Mobile Telecommunications - 2000 (IMT-2000) standard and more specifically the Satellite component of it, is investigated as a potential alternative for communications to aircraft mobile users en-route and in terminal area. Its application to Air Traffic Management (ATM) communication needs is considered. A summary of the specifications of IMT-2000 satellite standards are outlined. It is shown via a system research analysis that it is possible to support most air traffic communication needs via an IMT-2000 infrastructure. This technology can compliment existing, or future digital aeronautical communications technologies such as VDL2, VDL3, Mode S, and UAT.

  16. National Emission Standards for Hazardous Air Pollutants—Calendar Year 2010 INL Report for Radionuclides (2011)

    Energy Technology Data Exchange (ETDEWEB)

    Mark Verdoorn; Tom Haney

    2011-06-01

    This report documents the calendar Year 2010 radionuclide air emissions and resulting effective dose equivalent to the maximally exposed individual member of the public from operations at the Department of Energy's Idaho National Laboratory Site. This report was prepared in accordance with the Code of Federal Regulations, Title 40, 'Protection of the Environment,' Part 61, 'National Emission Standards for Hazardous Air Pollutants,' Subpart H, 'National Emission Standards for Emissions of Radionuclides Other than Radon from Department of Energy Facilities.'

  17. 75 FR 1566 - Public Hearings for Reconsideration of the 2008 National Ambient Air Quality Standards for Ozone

    Science.gov (United States)

    2010-01-12

    ... Ambient Air Quality Standards for Ozone AGENCY: Environmental Protection Agency (EPA). ACTION... proposed rule, ``Reconsideration of the 2008 National Ambient Air Quality Standards for Ozone,'' which was... the following Web site: http://www.epa.gov/ttn/naaqs/standards/ozone/s_o3_cr_fr.html for the...

  18. 76 FR 48073 - Public Hearing for Secondary National Ambient Air Quality Standards for Oxides of Nitrogen and...

    Science.gov (United States)

    2011-08-08

    ... AGENCY 40 CFR Part 50 RIN 2060-AO72 Public Hearing for Secondary National Ambient Air Quality Standards... titled ``Secondary National Ambient Air Quality Standards for Oxides of Nitrogen and Sulfur'' which was....epa.gov/ttn/naaqs/standards/no2so2sec/cr_fr.html . FOR FURTHER INFORMATION CONTACT: If you would...

  19. Source geometry factors for HDR ¹⁹²Ir brachytherapy secondary standard well-type ionization chamber calibrations.

    Science.gov (United States)

    Shipley, D R; Sander, T; Nutbrown, R F

    2015-03-21

    Well-type ionization chambers are used for measuring the source strength of radioactive brachytherapy sources before clinical use. Initially, the well chambers are calibrated against a suitable national standard. For high dose rate (HDR) (192)Ir, this calibration is usually a two-step process. Firstly, the calibration source is traceably calibrated against an air kerma primary standard in terms of either reference air kerma rate or air kerma strength. The calibrated (192)Ir source is then used to calibrate the secondary standard well-type ionization chamber. Calibration laboratories are usually only equipped with one type of HDR (192)Ir source. If the clinical source type is different from that used for the calibration of the well chamber at the standards laboratory, a source geometry factor, k(sg), is required to correct the calibration coefficient for any change of the well chamber response due to geometric differences between the sources. In this work we present source geometry factors for six different HDR (192)Ir brachytherapy sources which have been determined using Monte Carlo techniques for a specific ionization chamber, the Standard Imaging HDR 1000 Plus well chamber with a type 70010 HDR iridium source holder. The calculated correction factors were normalized to the old and new type of calibration source used at the National Physical Laboratory. With the old Nucletron microSelectron-v1 (classic) HDR (192)Ir calibration source, ksg was found to be in the range 0.983 to 0.999 and with the new Isodose Control HDR (192)Ir Flexisource k(sg) was found to be in the range 0.987 to 1.004 with a relative uncertainty of 0.4% (k = 2). Source geometry factors for different combinations of calibration sources, clinical sources, well chambers and associated source holders, can be calculated with the formalism discussed in this paper.

  20. A primary standard for activity concentration of {sup 220}Rn (thoron) in air

    Energy Technology Data Exchange (ETDEWEB)

    Roettger, Annette, E-mail: Annette.roettger@ptb.d [Physikalisch-Technische Bundesanstalt, Bundesallee 100, D-38116 Braunschweig (Germany); Honig, Anja; Dersch, Rainer; Ott, Oliver; Arnold, Dirk [Physikalisch-Technische Bundesanstalt, Bundesallee 100, D-38116 Braunschweig (Germany)

    2010-07-15

    Due to the short half-life of Rn-220, a primary standard for activity concentration of Rn-220 (thoron) in air (i.e. a homogeneous reference atmosphere consisting of a certified activity in a certified volume) has been considered unachievable in the past. Traceability of Rn-222 reference atmospheres is achievable using radon gas activity standards (; ) and standard volumes, and is an established method. For the short-lived radionuclide Rn-220 this procedure is not feasible, since no Rn-220 gas activity standard with a reasonable activity can be produced. This leads to a lack of traceability for measurements of Rn-220 activity concentration: only atmospheres monitored by reference instruments (i.e. secondary standards) are available. The new primary standard for the activity concentration of {sup 220}Rn developed by PTB now closes this gap in radon metrology.

  1. 77 FR 46371 - National Emission Standards for Hazardous Air Pollutants for the Portland Cement Manufacturing...

    Science.gov (United States)

    2012-08-03

    ... rule (77 FR 42368, July 18, 2012) should be addressed to Ms. Sharon Nizich, Office of Air Quality... Register on July 18, 2012, and is available at: http://www.gpo.gov/fdsys/pkg/FR-2012-07-18/pdf/2012-16166... the Portland Cement Manufacturing Industry and Standards of Performance for Portland Cement...

  2. 75 FR 75937 - National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion...

    Science.gov (United States)

    2010-12-07

    ... unusually low frequency, equipment overload, capacity or energy deficiency, or unacceptable voltage level..., or to prevent the occurrence of, unusually low frequency, equipment overload, capacity or energy... AGENCY 40 CFR Part 63 RIN 2060-AP36 National Emission Standards for Hazardous Air Pollutants...

  3. 76 FR 44829 - Federal Motor Vehicle Safety Standards; Air Brake Systems

    Science.gov (United States)

    2011-07-27

    ... 6x4 tractor with a 190-inch wheelbase, equipped with a hybrid disc brake configuration. The vehicle... National Highway Traffic Safety Administration 49 CFR Part 571 RIN 2127-AK84 Federal Motor Vehicle Safety... published a final rule that amended the Federal motor vehicle safety standard for air brake systems...

  4. 75 FR 9647 - National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion...

    Science.gov (United States)

    2010-03-03

    ... non-emergency two-stroke lean burn (2SLB) >500 HP located at a major source of HAP emissions, New or... Internal Combustion Engines; Final Rule #0;#0;Federal Register / Vol. 75, No. 41 / Wednesday, March 3, 2010... Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines...

  5. 77 FR 16508 - National Emission Standards for Hazardous Air Pollutant Emissions: Group IV Polymers and Resins...

    Science.gov (United States)

    2012-03-21

    ..., was published on January 9, 2012 (77 FR 1268). EPA has established the public docket for the proposed...: Group IV Polymers and Resins; Pesticide Active Ingredient Production; and Polyether Polyols Production... pollutants: National Emission Standards for Hazardous Air Pollutant Emissions: Group IV Polymers and...

  6. 75 FR 65594 - Approval and Promulgation of Air Quality Implementation Plans; Ohio; Particulate Matter Standards

    Science.gov (United States)

    2010-10-26

    .... Hand Delivery: Jay Bortzer, Chief, Air Programs Branch (AR-18J), U.S. Environmental Protection Agency... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION... Matter Standards AGENCY: Environmental Protection Agency (EPA). ACTION: Proposed rule. SUMMARY: EPA...

  7. 76 FR 81903 - National Emission Standards for Hazardous Air Pollutants: Ferroalloys Production; Extension of...

    Science.gov (United States)

    2011-12-29

    ... Pollutants: Ferroalloys Production'' is being extended for 22 days. DATES: Comments. The public comment period for the proposed rule published November 23, 2011 (76 FR 72508), is being extended for 22 days to... AGENCY 40 CFR Part 63 RIN 2060-AQ11 National Emission Standards for Hazardous Air Pollutants:...

  8. 75 FR 32682 - National Emission Standards for Hazardous Air Pollutants for Major Sources: Industrial...

    Science.gov (United States)

    2010-06-09

    ... the deadline for written comments on the proposed rules (75 FR 32006 (major source boilers), 75 FR 31896 (area source boilers), 75 FR 31938 (CISWI), and 75 FR 31844 (waste definition)) to August 3, 2010... 2050-AG44 National Emission Standards for Hazardous Air Pollutants for Major Sources:...

  9. 78 FR 10005 - National Emission Standards for Hazardous Air Pollutants for the Portland Cement Manufacturing...

    Science.gov (United States)

    2013-02-12

    ... A. PM Parametric Monitoring B. Scaling for Continuous Parametric Monitoring of THC for Alternative... continuous opacity monitoring system CO 2 carbon dioxide CPMS continuous parametric monitoring system D/F... Reporting Tool FR Federal Register gr/dscf grains per dry standard cubic foot HAP hazardous air...

  10. 76 FR 72507 - National Emissions Standards for Hazardous Air Pollutants: Ferroalloys Production

    Science.gov (United States)

    2011-11-23

    ...-Product Recovery Plants (Benzene NESHAP) (54 Federal Register (FR) 38044, September 14, 1989). The first... Reporting Tool FR Federal Register gr/dscf grains per dry standard cubic foot HAP hazardous air pollutants... (PAH), Chromium, Arsenic, Nickel, and Mercury. a All estimates are for implementation year 2015...

  11. 76 FR 29031 - National Emissions Standards for Hazardous Air Pollutants: Secondary Lead Smelting

    Science.gov (United States)

    2011-05-19

    ... and maintenance OAQPS Office of Air Quality Planning and Standards ODW Office of Drinking Water OECA... Substances and Disease Registry BACT best available control technology BLDS bag leak detection system CAA... System TTN Technology Transfer Network UF uncertainty factor /m\\3\\ microgram per cubic meter UL...

  12. 76 FR 13514 - National Emission Standards for Hazardous Air Pollutants for Chemical Manufacturing Area Sources

    Science.gov (United States)

    2011-03-14

    ... Manufacturing Area Sources AGENCY: Environmental Protection Agency (EPA). ACTION: Final rule. SUMMARY: EPA is... Manufacturing Area Sources. Among the provisions EPA is reconsidering is a requirement that certain affected... published final National Emission Standards for Hazardous Air Pollutants for Chemical Manufacturing...

  13. 77 FR 22847 - National Emission Standards for Hazardous Air Pollutants for Polyvinyl Chloride and Copolymers...

    Science.gov (United States)

    2012-04-17

    ... Hazardous Air Pollutants for Polyvinyl Chloride and Copolymers Production; Final Rule #0;#0;Federal Register... Polyvinyl Chloride and Copolymers Production AGENCY: Environmental Protection Agency (EPA). ACTION: Final... Polyvinyl Chloride and Copolymers Production. The final rules establish emission standards that apply at...

  14. 76 FR 30604 - National Emission Standards for Hazardous Air Pollutants for Polyvinyl Chloride and Copolymers...

    Science.gov (United States)

    2011-05-26

    ... Polyvinyl Chloride and Copolymers Production AGENCY: Environmental Protection Agency (EPA). ACTION: Proposed..., the proposed rule, National Emission Standards for Hazardous Air Pollutants for Polyvinyl Chloride and... Polyvinyl Chloride and Copolymers Production, under Docket ID No. EPA-HQ-OAR-2002-0037 (available at...

  15. National Emission Standards for Hazardous Air Pollutants—Calendar Year 2011 INL Report for Radionuclides (2012)

    Energy Technology Data Exchange (ETDEWEB)

    Mark Verdoorn; Tom Haney

    2012-06-01

    This report documents the calendar year 2011 radionuclide air emissions and resulting effective dose equivalent to the maximally exposed individual member of the public from operations at the Department of Energy's Idaho National Laboratory Site. This report was prepared in accordance with the Code of Federal Regulations, Title 40, 'Protection of the Environment,' Part 61, 'National Emission Standards for Hazardous Air Pollutants,' Subpart H, 'National Emission Standards for Emissions of Radionuclides Other than Radon from Department of Energy Facilities.' The effective dose equivalent to the maximally exposed individual member of the public was 4.58E-02 mrem per year, 0.46 percent of the 10 mrem standard.

  16. National Emission Standards for Hazardous Air Pollutants. Calendar Year 2012 INL Report for Radionuclides (2013)

    Energy Technology Data Exchange (ETDEWEB)

    Verdoorn, Mark; Haney, Tom

    2013-06-01

    This report documents the calendar year 2011 radionuclide air emissions and resulting effective dose equivalent to the maximally exposed individual member of the public from operations at the Department of Energy’s Idaho National Laboratory Site. This report was prepared in accordance with the Code of Federal Regulations, Title 40, ''Protection of the Environment,'' Part 61, ''National Emission Standards for Hazardous Air Pollutants,'' Subpart H, ''National Emission Standards for Emissions of Radionuclides Other than Radon from Department of Energy Facilities.'' The effective dose equivalent to the maximally exposed individual member of the public was 4.58E-02 mrem per year, 0.46 percent of the 10 mrem standard.

  17. National Emission Standards for Hazardous Air Pollutants. Calendar Year 2013 INL Report for Radionuclides [2014

    Energy Technology Data Exchange (ETDEWEB)

    Verdoorn, Mark; Haney, Tom

    2014-06-01

    This report documents the calendar year 2013 radionuclide air emissions and resulting effective dose equivalent to the maximally exposed individual member of the public from operations at the Department of Energy’s Idaho National Laboratory Site. This report was prepared in accordance with the Code of Federal Regulations, Title 40, ''Protection of the Environment,'' Part 61, ''National Emission Standards for Hazardous Air Pollutants,'' Subpart H, ''National Emission Standards for Emissions of Radionuclides Other than Radon from Department of Energy Facilities.'' The effective dose equivalent to the maximally exposed individual member of the public was 3.02 E-02 mrem per year, 0.30 percent of the 10 mrem standard.

  18. KERMA-based radiation dose management system for real-time patient dose measurement

    Science.gov (United States)

    Kim, Kyo-Tae; Heo, Ye-Ji; Oh, Kyung-Min; Nam, Sang-Hee; Kang, Sang-Sik; Park, Ji-Koon; Song, Yong-Keun; Park, Sung-Kwang

    2016-07-01

    Because systems that reduce radiation exposure during diagnostic procedures must be developed, significant time and financial resources have been invested in constructing radiation dose management systems. In the present study, the characteristics of an existing ionization-based system were compared to those of a system based on the kinetic energy released per unit mass (KERMA). Furthermore, the feasibility of using the KERMA-based system for patient radiation dose management was verified. The ionization-based system corrected the effects resulting from radiation parameter perturbations in general radiography whereas the KERMA-based system did not. Because of this difference, the KERMA-based radiation dose management system might overestimate the patient's radiation dose due to changes in the radiation conditions. Therefore, if a correction factor describing the correlation between the systems is applied to resolve this issue, then a radiation dose management system can be developed that will enable real-time measurement of the patient's radiation exposure and acquisition of diagnostic images.

  19. 75 FR 32178 - Release of Final Document Related to the Review of the National Ambient Air Quality Standards for...

    Science.gov (United States)

    2010-06-07

    ... titled, Carbon Monoxide National Ambient Air Quality Standards: Scope and Methods Plan for Health Risk... AGENCY Release of Final Document Related to the Review of the National Ambient Air Quality Standards for... describes ] quantitative analyses that have been conducted as part of the review of the National Ambient...

  20. SU-E-I-53: Comparison of Kerma-Area-Product Between the Micro-Angiographic Fluoroscope (MAF) and a Flat Panel Detector (FPD) as Used in Neuro-Endovascular Procedures

    Energy Technology Data Exchange (ETDEWEB)

    Vijayan, S; Rana, V; Nagesh, S Setlur; Xiong, Z; Rudin, S; Bednarek, D [Toshiba Stroke and Vascular Research Center, University at Buffalo, Buffalo, NY (United States)

    2015-06-15

    Purpose: To determine the reduction of integral dose to the patient when using the micro-angiographic fluoroscope (MAF) compared to when using the standard flat-panel detector (FPD) for the techniques used during neurointerventional procedures. Methods: The MAF is a small field-of-view, high resolution x-ray detector which captures 1024 x 1024 pixels with an effective pixel size of 35μm and is capable of real-time imaging up to 30 frames per second. The MAF was used in neuro-interventions during those parts of the procedure when high resolution was needed and the FPD was used otherwise. The technique parameters were recorded when each detector was used and the kerma-area-product (KAP) per image frame was determined. KAP values were calculated for seven neuro interventions using premeasured calibration files of output as a function of kVp and beam filtration and included the attenuation of the patient table for the frontal projections to be more representative of integral patient dose. The air kerma at the patient entrance was multiplied by the beam area at that point to obtain the KAP values. The ranges of KAP values per frame were determined for the range of technique parameters used during the clinical procedures. To appreciate the benefit of the higher MAF resolution in the region of interventional activity, DA technique parameters were generally used with the MAF. Results: The lowest and highest values of KAP per frame for the MAF in DA mode were 4 and 50 times lower, respectively, compared to those of the FPD in pulsed fluoroscopy mode. Conclusion: The MAF was used in those parts of the clinical procedures when high resolution and image quality was essential. The integral patient dose as represented by the KAP value was substantially lower when using the MAF than when using the FPD due to the much smaller volume of tissue irradiated. This research was supported in part by Toshiba Medical Systems Corporation and NIH Grant R01EB002873.

  1. Air

    International Nuclear Information System (INIS)

    In recent years several regulations and standards for air quality and limits for air pollution were issued or are in preparation by the European Union, which have severe influence on the environmental monitoring and legislation in Austria. This chapter of the environmental control report of Austria gives an overview about the legal situation of air pollution control in the European Union and in specific the legal situation in Austria. It gives a comprehensive inventory of air pollution measurements for the whole area of Austria of total suspended particulates, ozone, volatile organic compounds, nitrogen oxides, sulfur dioxide, carbon monoxide, heavy metals, benzene, dioxin, polycyclic aromatic hydrocarbons and eutrophication. For each of these pollutants the measured emission values throughout Austria are given in tables and geographical charts, the environmental impact is discussed, statistical data and time series of the emission sources are given and legal regulations and measures for an effective environmental pollution control are discussed. In particular the impact of fossil-fuel power plants on the air pollution is analyzed. (a.n.)

  2. Dose assessment in contrast enhanced digital mammography using simple phantoms simulating standard model breasts

    Science.gov (United States)

    Bouwman, R. W.; van Engen, R. E.; Young, K. C.; Veldkamp, W. J. H.; Dance, D. R.

    2015-01-01

    Slabs of polymethyl methacrylate (PMMA) or a combination of PMMA and polyethylene (PE) slabs are used to simulate standard model breasts for the evaluation of the average glandular dose (AGD) in digital mammography (DM) and digital breast tomosynthesis (DBT). These phantoms are optimized for the energy spectra used in DM and DBT, which normally have a lower average energy than used in contrast enhanced digital mammography (CEDM). In this study we have investigated whether these phantoms can be used for the evaluation of AGD with the high energy x-ray spectra used in CEDM. For this purpose the calculated values of the incident air kerma for dosimetry phantoms and standard model breasts were compared in a zero degree projection with the use of an anti scatter grid. It was found that the difference in incident air kerma compared to standard model breasts ranges between -10% to +4% for PMMA slabs and between 6% and 15% for PMMA-PE slabs. The estimated systematic error in the measured AGD for both sets of phantoms were considered to be sufficiently small for the evaluation of AGD in quality control procedures for CEDM. However, the systematic error can be substantial if AGD values from different phantoms are compared.

  3. Characterization of a 137Cs standard source for calibration purposes ar CRCN-NE

    International Nuclear Information System (INIS)

    Radiation protection monitoring instruments should be calibrated by accredited calibration laboratories. To offer calibration services, a laboratory must accomplish all requirements established by the national regulatory agency. The Calibration Service of the Centro Regional de Ciencias Nucleares (CRCN-NE), Comissao Nacional de Energia Nuclear, Recife, Brazil, is trying to achieve this accreditation. In the present work, a 137Cs standard source was characterized following the national and international recommendations and the results are presented. This source is a commercially available single source irradiator model 28-8A, manufactured by JLShepherd and Associates, with initial activity of 444 GBq (05/13/03). To provide different air kerma rates, as required for the calibration of portable radiation monitors, this irradiator have a set of four lead attenuators with different thickness, providing attenuation factors equal to 2, 4, 10 and 100 times (nominally). The performed tests included: size and uniformity of the radiation standard field at calibration reference position, variation of the air kerma rate for different lead attenuators, determination of attenuation factors for each lead attenuator configuration, and determination of the radiation scattering at the calibration reference position. The results showed the usefulness of the 137Cs standard source for the calibration of radiation protection monitoring detectors. (author)

  4. Establishment of soft x-ray reference fields for performance tests of radiation measuring instruments based on national standard

    International Nuclear Information System (INIS)

    In the Japanese Industrial Standard, JIS Z 4511 sets the condition of X-ray reference fields to be used for the performance test of radiation measuring instruments for radiation protection. With the soft X-ray generator installed in the Facility of Radiation Standards in Nuclear Science Research Institute, we have established four series of soft X-ray reference fields with quality index of 0.6, 0.7, 0.8 and 0.9 based on JIS Z 4511. In this article, quality of the X-ray fields, X-ray spectra, conversion coefficients to the dose equivalents from Air-Kerma were evaluated in the soft X-ray fields produced with X-ray tube voltage ranging from 6 kV to 100 kV, and set soft X-ray reference fields based on Japanese Industrial Standard about 42 qualities. As a result, this X-ray reference fields met a domestic setting condition well and precision was good for conversion factors to various dose equivalents from Air- Kerma and we confirmed the soundness of the spectrum of each X-ray quality. By this, it is found that dose equivalent standard with good precision and wide range of test energy points and dose rates can be provided, for the performance tests such as the energy characteristic and the direction characteristic for various radiation instruments. (author)

  5. A simple device for the measurement of kerma based on commercial PIN photo diodes

    Science.gov (United States)

    Kushpil, V.; Kushpil, S.; Huna, Z.

    2012-04-01

    The development of a dose reader for the measurement of the radiation dose from neutron and ionizing radiation is presented. The dose reader (kerma meter) is using as active element commercial PIN diodes with long base, which can provide a maximal dependence of the lifetime of minority carriers from the absorbed dose. We consider a simple theory of PIN diodes for the role of the kerma meter and discuss the idea for optimization of the calibration procedure. The characteristics of the dosimeter were measured for a few types of commercial diodes. The device can be useful for many practical tasks of control for radiation environments in the environment, nuclear physics and for industrial application.

  6. Calculated neutron KERMA factors based on the LLNL ENDL data file. Volume 27

    International Nuclear Information System (INIS)

    Neutron KERMA factors calculated from the LLNL ENDL data file are tabulated for 15 composite materials and for the isotopes or elements in the ENDL file from Z = 1 to Z = 29. The incident neutron energies range from 1.882 x 10-5 to 20. MeV for the composite materials and from 1.30 x 10-9 to 20. MeV for the isotopes and elements

  7. Studies on effective atomic number, electron density and kerma for some fatty acids and carbohydrates

    DEFF Research Database (Denmark)

    Manohara, S.R.; Hanagodimath, S.M.; Gerward, Leif

    2008-01-01

    The effective atomic number, Z(eff), the effective electron density, N-el, and kerma have been calculated for some fatty acids and carbohydrates for photon interaction in the extended energy range from 1 keV to 100 GeV using an accurate database of photon-interaction cross sections and the Win......XCom program. The significant variation of Z(eff) and N-el is due to the variations in the dominance of different interaction processes in different energy regions. The maximum values of Z(eff) and N-el are found in the low-energy range, where photoelectric absorption is the main interaction process...... is also made with the single values of the Z(eff) and N-el provided by the program XMuDat. It is also observed that carbohydrates have a larger kerma than fatty acids in the low-energy region, where photoelectric absorption dominates. In contrast, fatty acids have a larger kerma than carbohydrates...

  8. Technology development for evaluation of operational quantities and measurement standard in radiation protection

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Si Young; Lee, T. Y.; Kim, J. L.; Kim, B. H.; Chung, K. K.; Lee, J. I.; Park, T. S.; Ha, S. H.; Oh, P. J.; Jun, K. J

    1999-03-01

    A study on the fabrication of a new personal thermo-luminescence dosimeter, which can evaluate the personal dose equivalent H{sub p}(d), has been performed. Optimum conditions for fabrications of a LiF:Mg, Cu, Na, Si TL phosphor powder has been determined and a disc type TL pellet has been fabricated from this TL powder. Another type of CaSO{sub 4}:Dy, Mo TL material has been also fabricated. These two TL materials have shown greater TL sensitivity than the foreign-made commercial TL materials. Mono-energetic florescence X-rays from 8.6 response have been constructed and evaluated for the performance of the purity, air kerma, beam uniformity and distribution,and scattered fraction of X-rays.A free-air ionization chamber for the absolute measurement of air kerma in medium X-ray has been designed and constructed. Experimental results showed that the homemade chamber leaves nothing to be desired, compared with the national standard chambers in other advanced countries. Gas proportional counting system has been designed and constructed for absolute activity measurements of gaseous radionuclides. Unattached fractions of radon progeny were evaluated in the characteristic study on the detection of radon progeny.

  9. Study on an air quality evaluation model for Beijing City under haze-fog pollution based on new ambient air quality standards.

    Science.gov (United States)

    Li, Li; Liu, Dong-Jun

    2014-08-28

    Since 2012, China has been facing haze-fog weather conditions, and haze-fog pollution and PM2.5 have become hot topics. It is very necessary to evaluate and analyze the ecological status of the air environment of China, which is of great significance for environmental protection measures. In this study the current situation of haze-fog pollution in China was analyzed first, and the new Ambient Air Quality Standards were introduced. For the issue of air quality evaluation, a comprehensive evaluation model based on an entropy weighting method and nearest neighbor method was developed. The entropy weighting method was used to determine the weights of indicators, and the nearest neighbor method was utilized to evaluate the air quality levels. Then the comprehensive evaluation model was applied into the practical evaluation problems of air quality in Beijing to analyze the haze-fog pollution. Two simulation experiments were implemented in this study. One experiment included the indicator of PM2.5 and was carried out based on the new Ambient Air Quality Standards (GB 3095-2012); the other experiment excluded PM2.5 and was carried out based on the old Ambient Air Quality Standards (GB 3095-1996). Their results were compared, and the simulation results showed that PM2.5 was an important indicator for air quality and the evaluation results of the new Air Quality Standards were more scientific than the old ones. The haze-fog pollution situation in Beijing City was also analyzed based on these results, and the corresponding management measures were suggested.

  10. Hospital ventilation standards and energy conservation: chemical contamination of hospital air. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Rainer, D.; Michaelsen, G.S.

    1980-03-01

    In an era of increasing energy conservation consciousness, a critical reassessment of the validity of hospital ventilation and thermal standards is made. If current standards are found to be excessively conservative, major energy conservation measures could be undertaken by rebalancing and/or modification of current HVAC systems. To establish whether or not reducing ventilation rates would increase airborne chemical contamination to unacceptable levels, a field survey was conducted to develop an inventory and dosage estimates of hospital generated airborne chemical contaminants to which patients, staff, and visitors are exposed. The results of the study are presented. Emphasis is on patient exposure, but an examination of occupational exposure was also made. An in-depth assessment of the laboratory air environment is documented. Housekeeping products used in survey hospitals, hazardous properties of housekeeping chemicals and probable product composition are discussed in the appendices.

  11. Role of science and judgment in setting national ambient air quality standards: how low is low enough?

    OpenAIRE

    McClellan, Roger O.

    2011-01-01

    The Clean Air Act (CAA) requires listing as criteria air pollutants those pollutants that arise from multiple sources and are found across the United States. The original list included carbon monoxide, nitrogen oxides, sulfur oxides, particulate matter, photochemical oxidants (later regulated as ozone), and hydrocarbons. Later, the listing of hydrocarbons was revoked and lead was listed. The CAA requires the EPA Administrator to set National Ambient Air Quality Standards (NAAQS) for these pol...

  12. 78 FR 29815 - Control of Air Pollution From Motor Vehicles: Tier 3 Motor Vehicle Emission and Fuel Standards

    Science.gov (United States)

    2013-05-21

    ... Standard 3. Per-Gallon Sulfur Caps B. Refinery Air Permitting Interactions 1. Background on New Source... Rules 8. Summary of SBREFA Panel Process and Panel Outreach D. Unfunded Mandates Reform Act E. Executive... from inventories developed for the Final Cross-State Air Pollution Rule (76 FR 48208, August 8,...

  13. 78 FR 20881 - Control of Air Pollution From Motor Vehicles: Tier 3 Motor Vehicle Emission and Fuel Standards...

    Science.gov (United States)

    2013-04-08

    ... period will end on June 13, 2013. ADDRESSES: The hearings will be held at the following locations: The April 24, 2013 hearing will be held at the Sonesta Hotel Philadelphia, 1800 Market Street, Philadelphia... National Ambient Air Quality Standards. Motor vehicles are an important source of exposure to air...

  14. Development, enhancement, and evaluation of aircraft measurement techniques for national ambient air quality standard criteria pollutants

    Science.gov (United States)

    Brent, Lacey Cluff

    The atmospheric contaminants most harmful to human health are designated Criteria Pollutants. To help Maryland attain the national ambient air quality standards (NAAQS) for Criteria Pollutants, and to improve our fundamental understanding of atmospheric chemistry, I conducted aircraft measurements in the Regional Atmospheric Measurement Modeling Prediction Program (RAMMPP). These data are used to evaluate model simulations and satellite observations. I developed techniques for improving airborne observation of two NAAQS pollutants, particulate matter (PM) and nitrogen dioxide (NO2). While structure and composition of organic aerosol are important for understanding PM formation, the molecular speciation of organic ambient aerosol remains largely unknown. The spatial distribution of reactive nitrogen is likewise poorly constrained. To examine water-soluble organic aerosol (WSOA) during an air pollution episode, I designed and implemented a shrouded aerosol inlet system to collect PM onto quartz fiber filters from a Cessna 402 research aircraft. Inlet evaluation conducted during a side-by-side flight with the NASA P3 demonstrated agreement to within 30%. An ion chromatographic mass spectrometric method developed using the NIST Standard Reference Material (SRM) 1649b Urban Dust, as a surrogate material resulted in acidic class separation and resolution of at least 34 organic acids; detection limits approach pg/g concentrations. Analysis of aircraft filter samples resulted in detection of 8 inorganic species and 16 organic acids of which 12 were quantified. Aged, re-circulated metropolitan air showed a greater number of dicarboxylic acids compared to air recently transported from the west. While the NAAQS for NO2 is rarely exceeded, it is a precursor molecule for ozone, America's most recalcitrant pollutant. Using cavity ringdown spectroscopy employing a light emitting diode (LED), I measured vertical profiles of NO2 (surface to 2.5 km) west (upwind) of the Baltimore

  15. 40 CFR Appendix T to Part 50 - Interpretation of the Primary National Ambient Air Quality Standards for Oxides of Sulfur (Sulfur...

    Science.gov (United States)

    2010-07-01

    ... Ambient Air Quality Standards for Oxides of Sulfur (Sulfur Dioxide) T Appendix T to Part 50 Protection of... AIR QUALITY STANDARDS Pt. 50, App. T Appendix T to Part 50—Interpretation of the Primary National Ambient Air Quality Standards for Oxides of Sulfur (Sulfur Dioxide) 1. General (a) This appendix...

  16. 40 CFR Appendix H to Part 50 - Interpretation of the 1-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone

    Science.gov (United States)

    2010-07-01

    ... and Secondary National Ambient Air Quality Standards for Ozone H Appendix H to Part 50 Protection of... AIR QUALITY STANDARDS Pt. 50, App. H Appendix H to Part 50—Interpretation of the 1-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone 1. General This appendix explains how...

  17. 40 CFR Appendix I to Part 50 - Interpretation of the 8-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone

    Science.gov (United States)

    2010-07-01

    ... and Secondary National Ambient Air Quality Standards for Ozone I Appendix I to Part 50 Protection of... AIR QUALITY STANDARDS Pt. 50, App. I Appendix I to Part 50—Interpretation of the 8-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone 1. General. This appendix explains the...

  18. Comparison between calibration methods of kerma-area product (P{sub KA}); Comparacao entre metodos de calibracao do produto kerma-area (P{sub KA})

    Energy Technology Data Exchange (ETDEWEB)

    Navarro, V.C.C.; Macedo, E.M.; Pereira, L.C.S.; Modesto, I.F.; Ferreira, M.; Navarro, M.V.T., E-mail: valeria@ifba.edu.br [Instituto Federal da Bahia (LABPROSAUD/IFBA), Salvador, BA (Brazil). Laboratorio de Produtos para a Saude

    2015-07-01

    P{sub KA} is a relevant dosimetric quantity utilized mainly in interventional radiology procedures, and it's calibration essential for maintenance of the metrological reliability in measurements. As there are two methods to calibrate this kind of meters (substitution method and directly measuring kerma and area), the goal of this study was to compare them, in order to indicate which is the better option to be implanted at Calibration Laboratory Labprosaud/IFBA. The results showed a good equivalence between two methods, with minimal concordance of 99,2% between calibration factors. However, the substitution method ensure higher metrological reliability with uncertainties 60% lower. This method was implanted at Labprosaud. (author)

  19. National Emission Standards for Hazardous Air Pollutants - Radionuclide Emissions, Calendar Year 2010

    Energy Technology Data Exchange (ETDEWEB)

    NSTec Ecological and Environmental Monitoring

    2011-06-30

    The U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office operates the Nevada National Security Site (NNSS, formerly the Nevada Test Site) and North Las Vegas Facility (NLVF). From 1951 through 1992, the NNSS was the continental testing location for U.S. nuclear weapons. The release of radionuclides from NNSS activities has been monitored since the initiation of atmospheric testing. Limitation to underground detonations after 1962 greatly reduced radiation exposure to the public surrounding the NNSS. After nuclear testing ended in 1992, NNSS radiation monitoring focused on detecting airborne radionuclides from historically contaminated soils. These radionuclides are derived from re-suspension of soil (primarily by wind) and emission of tritium-contaminated soil moisture through evapotranspiration. Low amounts of tritium are also emitted to air at the NLVF, an NNSS support complex in North Las Vegas. To protect the public from harmful levels of man-made radiation, the Clean Air Act, National Emission Standards for Hazardous Air Pollutants (NESHAP) (Title 40 Code of Federal Regulations [CFR] Part 61 Subpart H) (CFR, 2010a) limits the release of radioactivity from a U.S. Department of Energy (DOE) facility to that which would cause 10 millirem per year (mrem/yr) effective dose equivalent to any member of the public. This limit does not include radiation unrelated to NNSS activities. Unrelated doses could come from naturally occurring radioactive elements, from sources such as medically or commercially used radionuclides, or from sources outside of the United States, such as those from the damaged Fukushima nuclear power plant in Japan. Because this report is intended to discuss radioactive air emissions during calendar year 2010, data on radionuclides in air from the 2011 Fukushima nuclear power plant releases are not presented but will be included in the report for calendar year 2011. The NNSS demonstrates compliance with the NESHAP

  20. Nonattainment of national ambient air quality standards: implications for energy policy

    Energy Technology Data Exchange (ETDEWEB)

    Garvey, D.B.; Streets, D.G.; Kotecki, R.; Senew, M.

    1979-10-01

    In accordance with the 1977 Clean Air Act Amendments, EPA established regulations governing new and existing sources of emissions in areas where the NAAQS are being exceeded. These requirements may constrain the implementation of a national energy policy to increase the use of coal in utilities and industries. The states designated the nonattainment areas and prepared State Implementation Plans, outlining strategies for attaining the standards by the deadline of December 31, 1982. This report contains maps of nonattainment areas for all pollutants and summaries of the attainment strategies for those pollutants most likely to affect fossil-fueled energy development - SO/sub 2/, TSP, and NO/sub x/. The review of SIPs indicates that attainment of SO/sub 2/ standards should be relatively easy. Attainment of TSP standards may be more difficult since point sources are already well controlled and further reductions in emissions will require controls on fugitive sources. NO/sub x/ nonattainment is currently limited to three small areas. The report also contains an examination of emission limitations in nonattainment areas and a national assessment of the potential constraints of nonattainment on energy development in 1985 to 1990. The assessment concludes that constraints on projected new coal-fired utilities should not be significant. Constraints on expanded industrial coal use from TSP nonattainment may be significant but the effects of SO/sub 2/ nonattainment should be limited.

  1. ASME N511-19XX, Standard for periodic in-service testing of nuclear air treatment, heating, ventilating and air conditioning systems

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-08-01

    A draft version of the Standard is presented in this document. The Standard covers the requirements for periodic in-service testing of nuclear safety-related air treatment, heating, ventilating, and air conditioning systems in nuclear facilities. The Standard provides a basis for the development of test programs and does not include acceptance criteria, except in cases where the results of one test influence the performance of other tests. The Standard covers general inspection and test requirements, reference values, inspection and test requirements, generic tests, acceptance criteria, in-service test requirements, testing following an abnormal incident, corrective action requirements, and quality assurance. Mandatory appendices provide a visual inspection checklist and four test procedures. Non-mandatory appendices provide additional information and guidance on mounting frame pressure leak test procedure, corrective action, challenge gas substitute selection criteria, and test program development. 8 refs., 10 tabs.

  2. Nevada Test Site National Emission Standards for Hazardous Air Pollutants Calendar Year 2007

    Energy Technology Data Exchange (ETDEWEB)

    Robert Grossman; Ronald Warren

    2008-06-01

    The Nevada Test Site (NTS) is operated by the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office. From 1951 through 1992, the NTS was operated as the nation's site for nuclear weapons testing. The release of man-made radionuclides from the NTS as a result of testing activities has been monitored since the first decade of atmospheric testing. After 1962, when nuclear tests were conducted only underground, the radiation exposure to the public surrounding the NTS was greatly reduced. After the 1992 moratorium on nuclear testing, radiation monitoring on the NTS focused on detecting airborne radionuclides which come from historically contaminated soils resuspended into the air (e.g., by winds) and tritium-contaminated soil moisture emitted to the air from soils through evapotranspiration. To protect the public from harmful levels of man-made radiation, the Clean Air Act, National Emission Standards for Hazardous Air Pollutants (NESHAP) (Title 40 Code of Federal Regulations [CFR] Part 61 Subpart H) limits the release of radioactivity from a U.S. Department of Energy facility (e.g., the NTS) to 10 millirem per year (mrem/yr) effective dose equivalent to any member of the public. This is the dose limit established for someone living off of the NTS from radionuclides emitted to air from the NTS. This limit does not include the radiation doses that members of the public may receive through the intake of radioactive particles unrelated to NTS activities, such as those that come from naturally occurring elements in the environment (e.g., naturally occurring radionuclides in soil or radon gas from the earth or natural building materials), or from other man-made sources (e.g., medical treatments). The NTS demonstrates compliance using environmental measurements of radionuclide air concentrations at critical receptor locations. This method was approved by the U.S. Environmental Protection Agency for use on the NTS in 2001 and has been the

  3. Inter-laboratory comparison study on measuring semi-volatile organic chemicals in standards and air samples.

    Science.gov (United States)

    Su, Yushan; Hung, Hayley

    2010-11-01

    Measurements of semi-volatile organic chemicals (SVOCs) were compared among 21 laboratories from 7 countries through the analysis of standards, a blind sample, an air extract, and an atmospheric dust sample. Measurement accuracy strongly depended on analytes, laboratories, and types of standards and samples. Intra-laboratory precision was generally good with relative standard deviations (RSDs) of triplicate injections laboratory variability, measured by RSDs of all measurements, was in the range of 2.8-58% in analyzing standards, and 6.9-190% in analyzing blind sample and air extract. Inter-laboratory precision was poorer when samples were subject to cleanup processes, or when SVOCs were quantified at low concentrations. In general, inter-laboratory differences up to a factor of 2 can be expected to analyze atmospheric SVOCs. When comparing air measurements from different laboratories, caution should be exercised if the data variability is less than the inter-laboratory differences.

  4. Air index compensated interferometer as a prospective novel primary standard for baseline calibrations

    International Nuclear Information System (INIS)

    We describe the status of the development of an interferometer for absolute distance measurements with an intrinsic compensation of the refractive index of air, intended as a primary standard for the calibration of geodetic baselines. Two frequency-doubled Nd:YAG lasers are offset locked with a frequency difference of ≈20 GHz at the infrared 1064 nm fundamental wavelength. The resulting synthetic wavelengths of 15 mm for the infrared and 7.5 mm for the frequency-doubled green light are used as the scale for the measurements. Longer synthetic wavelengths are generated by acousto-optic frequency shifters. Based on the dispersion in air between green and infrared light the refractive index can be compensated. The attempt is demanding since uncertainties of the interferometric measurements for the optical wavelengths are scaled by a factor of nearly 300 000 in the refractive index compensated result. First comparisons up to 50 m length between this interferometer and a HeNe reference are presented. The deviations are smaller than ± 200 µm and dominated by a non-linearity from problems in the collimation of the measurement beams. In the linear parts the deviations are below ± 100 µm. (paper)

  5. National Emission Standards for Hazardous Air Pollutants - Radionuclide Emissions Calendar Year 2012

    Energy Technology Data Exchange (ETDEWEB)

    Warren, R.

    2013-06-10

    The U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office (NNSA/NFO) operates the Nevada National Security Site (NNSS) and North Las Vegas Facility (NLVF). From 1951 through 1992, the NNSS was the continental testing location for U.S. nuclear weapons. The release of radionuclides from NNSS activities has been monitored since the initiation of atmospheric testing. Limitation to underground detonations after 1962 greatly reduced radiation exposure to the public surrounding the NNSS. After nuclear testing ended in 1992, NNSS radiation monitoring focused on detecting airborne radionuclides from historically contaminated soils. These radionuclides are derived from re-suspension of soil (primarily by wind) and emission of tritium-contaminated soil moisture through evapotranspiration. Low amounts of legacy-related tritium are also emitted to air at the NLVF, an NNSS support complex in North Las Vegas. To protect the public from harmful levels of man-made radiation, the Clean Air Act, National Emission Standards for Hazardous Air Pollutants (NESHAP) (Title 40 Code of Federal Regulations [CFR] Part 61 Subpart H) (CFR 2010a) limits the release of radioactivity from a U.S. Department of Energy (DOE) facility to that which would cause 10 millirem per year (mrem/yr) effective dose equivalent to any member of the public. This limit does not include radiation unrelated to NNSS activities. Unrelated doses could come from naturally occurring radioactive elements, from sources such as medically or commercially used radionuclides, or from sources outside of the United States, such as the damaged Fukushima nuclear power plant in Japan in 2011. NNSA/NFO demonstrates compliance with the NESHAP limit by using environmental measurements of radionuclide air concentrations at critical receptor locations on the NNSS (U.S. Environmental Protection Agency [EPA] and DOE 1995). This method was approved by the EPA for use on the NNSS in 2001 (EPA 2001a) and has

  6. National Emission Standards for Hazardous Air Pollutants - Radionuclide Emissions, Calendar Year 2011

    Energy Technology Data Exchange (ETDEWEB)

    NSTec Ecological and Environmental Monitoring

    2012-06-19

    The U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office operates the Nevada National Security Site (NNSS) and North Las Vegas Facility (NLVF). From 1951 through 1992, the NNSS was the continental testing location for U.S. nuclear weapons. The release of radionuclides from NNSS activities has been monitored since the initiation of atmospheric testing. Limitation to underground detonations after 1962 greatly reduced radiation exposure to the public surrounding the NNSS. After nuclear testing ended in 1992, NNSS radiation monitoring focused on detecting airborne radionuclides from historically contaminated soils. These radionuclides are derived from re-suspension of soil (primarily by wind) and emission of tritium-contaminated soil moisture through evapotranspiration. Low amounts of legacy-related tritium are also emitted to air at the NLVF, an NNSS support complex in North Las Vegas. To protect the public from harmful levels of man-made radiation, the Clean Air Act, National Emission Standards for Hazardous Air Pollutants (NESHAP) (Title 40 Code of Federal Regulations [CFR] Part 61 Subpart H) limits the release of radioactivity from a U.S. Department of Energy (DOE) facility to that which would cause 10 millirem per year (mrem/yr) effective dose equivalent to any member of the public. This limit does not include radiation unrelated to NNSS activities. Unrelated doses could come from naturally occurring radioactive elements, from sources such as medically or commercially used radionuclides, or from sources outside of the United States, such as the damaged Fukushima nuclear power plant in Japan. Radionuclides from the Fukushima nuclear power plant were detected at the NNSS in March 2011 and are discussed further in Section III. The NNSS demonstrates compliance with the NESHAP limit by using environmental measurements of radionuclide air concentrations at critical receptor locations. This method was approved by the EPA for use on the

  7. National Emission Standards for Hazardous Air Pollutants - Radionuclide Emissions Calendar Year 2013

    Energy Technology Data Exchange (ETDEWEB)

    Warren, R.

    2014-06-04

    The U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office (NNSA/NFO) operates the Nevada National Security Site (NNSS) and North Las Vegas Facility (NLVF). From 1951 through 1992, the NNSS was the continental testing location for U.S. nuclear weapons. The release of radionuclides from NNSS activities has been monitored since the initiation of atmospheric testing. Limitations to underground detonations after 1962 greatly reduced radiation exposure to the public surrounding the NNSS. After nuclear testing ended in 1992, NNSS radiation monitoring focused on detecting airborne radionuclides from historically contaminated soils. These radionuclides are derived from re-suspension of soil (primarily by wind) and emission of tritium-contaminated soil moisture through evapotranspiration. Low amounts of legacy-related tritium are also emitted to air at the NLVF, an NNSS support complex in North Las Vegas. To protect the public from harmful levels of man-made radiation, the Clean Air Act, National Emission Standards for Hazardous Air Pollutants (NESHAP) (Title 40 Code of Federal Regulations [CFR] Part 61 Subpart H) (CFR 2010a) limits the release of radioactivity from a U.S. Department of Energy (DOE) facility to that which would cause 10 millirem per year (mrem/yr) effective dose equivalent to any member of the public. This limit does not include radiation unrelated to NNSS activities. Unrelated doses could come from naturally occurring radioactive elements, from sources such as medically or commercially used radionuclides, or from sources outside of the United States, such as the damaged Fukushima nuclear power plant in Japan in 2011. NNSA/NFO demonstrates compliance with the NESHAP limit by using environmental measurements of radionuclide air concentrations at critical receptor locations on the NNSS (U.S. Environmental Protection Agency [EPA] and DOE 1995). This method was approved by the EPA for use on the NNSS in 2001 (EPA 2001a) and has

  8. National Emission Standards for Hazardous Air Pollutants - Radionuclide Emissions Calendar Year 2009

    International Nuclear Information System (INIS)

    The U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office operates the Nevada Test Site (NTS) and North Las Vegas Facility (NLVF). From 1951 through 1992, the NTS was the continental testing location for U.S. nuclear weapons. The release of radionuclides from NTS activities has been monitored since the initiation of atmospheric testing. Limitation to underground detonations after 1962 greatly reduced radiation exposure to the public surrounding the NTS. After nuclear testing ended in 1992, NTS radiation monitoring focused on detecting airborne radionuclides from historically contaminated soils. These radionuclides are derived from re-suspension of soil (primarily by wind) and emission of tritium-contaminated soil moisture through evapotranspiration. Low amounts of tritium were also emitted to air at the NLVF, an NTS support complex in North Las Vegas. To protect the public from harmful levels of man-made radiation, the Clean Air Act, National Emission Standards for Hazardous Air Pollutants (NESHAP) (Title 40 Code of Federal Regulations (CFR) Part 61 Subpart H) limits the release of radioactivity from a U.S. Department of Energy facility to 10 millirem per year (mrem/yr) effective dose equivalent to any member of the public. This limit does not include radiation not related to NTS activities. Unrelated doses could come from naturally occurring radioactive elements or from sources such as medically or commercially used radionuclides. The NTS demonstrates compliance with the NESHAP limit by using environmental measurements of radionuclide air concentrations at critical receptor locations. This method was approved by the U.S. Environmental Protection Agency for use on the NTS in 2001 and has been the sole method used since 2005. Six locations on the NTS have been established to act as critical receptor locations to demonstrate compliance with the NESHAP limit. These locations are actually pseudo-critical receptor stations, because no

  9. Nevada Test Site National Emission Standards for Hazardous Air Pollutants Calendar Year 2008

    Energy Technology Data Exchange (ETDEWEB)

    Ronald Warren and Robert F. Grossman

    2009-06-30

    The Nevada Test Site (NTS) is operated by the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office. From 1951 through 1992, the NTS was the continental testing location for U.S. nuclear weapons. The release of radionuclides from NTS activities has been monitored since the initiation of atmospheric testing. Limitation to under-ground detonations after 1962 greatly reduced radiation exposure to the public surrounding the NTS. After nuclear testing ended in 1992, NTS radiation monitoring focused on detecting airborne radionuclides from historically contaminated soils. These radionuclides are derived from re-suspension of soil (primarily by winds) and emission of tritium-contaminated soil moisture through evapotranspiration. Low amounts of tritium were also emitted to air at the North Las Vegas Facility (NLVF), an NTS support complex in the city of North Las Vegas. To protect the public from harmful levels of man-made radiation, the Clean Air Act, National Emission Standards for Hazardous Air Pollutants (NESHAP) (Title 40 Code of Federal Regulations [CFR] Part 61 Subpart H) (CFR, 2008a) limits the release of radioactivity from a U.S. Department of Energy facility (e.g., the NTS) to 10 millirem per year (mrem/yr) effective dose equivalent to any member of the public. This limit does not include radiation not related to NTS activities. Unrelated doses could come from naturally occurring radioactive elements or from other man-made sources such as medical treatments. The NTS demonstrates compliance with the NESHAP limit by using environmental measurements of radionuclide air concentrations at critical receptor locations. This method was approved by the U.S. Environmental Protection Agency for use on the NTS in 2001 and has been the sole method used since 2005. Six locations on the NTS have been established to act as critical receptor locations to demonstrate compliance with the NESHAP limit. These locations are actually pseudo

  10. CITY DEVELOPMENT FOR KEEPING POLLUTANT CONCENTRATIONS FROM MOTOR VEHICLES IN RESIDENTIAL AREAS IN ACCORDANCE WITH AIR QUALITY STANDARDS

    OpenAIRE

    Владимир Васильевич Балакин

    2016-01-01

    The dependency of carbon monoxide concentrations on wind speed has been obtained in the field studies. It is used in determining optimum ventilation modes for street space to ensure keeping the content of the toxic components from automobile exhaust in accordance with public health standards.Environmental basis for development optimization for busy primary streets has been provided to avoid dangerous levels of ambient air pollution with automobile emissions.Positive effect on air quality from...

  11. Exceedances of air quality standard level of PM2.5 in Japan caused by Siberian wildfires

    International Nuclear Information System (INIS)

    We revisited long-term observations of PM2.5 at ground-based stations in Japan during 2001–2012 to examine possible impacts of Siberian wildfires on regional air quality. Exceedances of Japan’s air quality standard for daily mean concentration (35 μg m−3) were observed several times at Rishiri Island in northern Japan in the spring of 2003 and 2008 when intense wildfires occurred in Siberia. Satellite observations showed that aerosols and CO originating from biomass burning were transported from Siberia toward Japan. The regional chemical transport model also demonstrated that the PM2.5 enhancements during high PM2.5 days (>35 μg m−3) were attributed to Siberian wildfires, suggesting that the contribution from Siberian biomass burning had a critical impact on exceedances of air quality standard level. The monthly (May) and annual mean PM2.5 concentrations in 2003 were about twice and 20% higher, respectively, than those of the long-term average at Rishiri Island, where the influence of Siberian wildfires was the largest in Japan. Except for 2003 and 2008, a high PM2.5 day due to Siberian wildfires was not identified. Although Siberian biomass burning does not affect the air quality standard of PM2.5 for the years without strong fires, it causes exceedance of the air quality standard level when intense fires occur. (letter)

  12. Reference and Equivalent Methods Used to Measure National Ambient Air Quality Standards (NAAQS) Criteria Air Pollutants - Volume I

    Science.gov (United States)

    There are a number of Federal Reference Method (FRM) and Federal Equivalent Method (FEM) systems used to monitor the six criteria air pollutants (Lead [Pb], Carbon Monoxide [CO], Sulfur Dioxide [SO2], Nitrogen Dioxide [NO2], Ozone [O3], Particulate Matter [PM]) to determine if an...

  13. Considerations of an air-quality standard to protect terrestrial vegetation from acidic precipitation

    Energy Technology Data Exchange (ETDEWEB)

    Evans, L.S.

    1981-01-01

    Studies on the effects of acidic precipitation which is here defined as wet or frozen deposition with a hydrogen ion concentration greater than 2.5 ..mu..eq 1/sup -1/, are reviewed. At the present time there is an inadequate amount of information that shows decreases in crop growth except for one field study. Most studies with plants (crops and forests) are inadequate for standard setting because they are not conducted in the field with adequate randomization of plots coupled with rigorous statistical analyses. Although visible injury to foliage has been documented in a variety of greenhouse studies, no experimental evidence demonstrates loss of field crop value or reduction in plant productivity due to visible foliar injury. Acidic precipitation can contribute nutrients to vegetation and could also influence leaching rates of nutrients from vegetation. Although these processes occur, there are no data that show changes in nutrient levels in foliage that relate to crop or natural ecosystem productivity. Experimental results show that fertilization of ferns is inhibited by current levels of acidic precipitation in the northeastern United States. However, the overall impacts of inhibited fertilization on perpetuation of the species or ecosystem productivity have not been evaluated. Simulated acidic precipitation has been shown to effect plant pathogens in greenhouse and field experiments. Simulated acidic precipitation inhibited pathogen activities under some circumstances and promoted pathogen activities under other circumstances. No conclusion can be drawn about the effects of current levels of precipitation acidity on plant pathogen-host interactions. From these data it must be concluded that research on the effects of acidic precipitation on terrestrial vegetation is too meager to draw any conclusions with regard to an air quality standard.

  14. The Ontario Energy Board`s draft standard supply service code: effects on air quality

    Energy Technology Data Exchange (ETDEWEB)

    Gibbons, J.; Bjorkquist, S. [Ontario Clean Air Alliance, Toronto, ON (Canada)

    1999-06-29

    The Ontario Clean Air Alliance (OCAA), a coalition of 67 organizations, takes issue with the Ontario Energy Board`s draft document `Standard Supply Service Code`, particularly sections 2.2.2. and 2.5.2 which they claim are not in the public interest unless the Ontario government implements the OCAA`s recommended emission caps. The alliance is of the view that without strict new environmental regulations the proposed Code would encourage the use of coal for electricity generation. Public health, the environment, consumer interests, job creation and promotion of a competitive electricity market would all be jeopardized by this development, the alliance states. The argument is supported by extensive reference to the Final Report of the Ontario Market Design Committee (MDC) which also emphasized the importance of combining the introduction of competition with appropriate environmental regulations, singling out the emission cap and trade program, and recommending that it be launched concurrently with the electricity market opening for competition. The view of the MDC was that public support for restructuring would not be forthcoming in the absence of regulatory measures to control power plant emissions. 25 refs.

  15. 77 FR 65823 - Control of Air Pollution From Aircraft and Aircraft Engines; Emission Standards and Test Procedures

    Science.gov (United States)

    2012-10-31

    ... AGENCY 40 CFR Parts 87 RIN 2060-AO70 Control of Air Pollution From Aircraft and Aircraft Engines... Turbofan or Turbojet Engines with Rated Output Above 26.7 kN'' should read as set forth below: Table 3 to Sec. 87.23--Tier 6 NOX Standards for New Subsonic Turbofan or Turbojet Engines With Rated Output...

  16. Microbial air-sampling equipment, part 1: meeting United States pharmacopeia chapter 797 standards.

    Science.gov (United States)

    Kastango, Eric S

    2008-01-01

    The most recent changes to Chapter 797 of the United States Pharmcopeia-National Formulary initiated an intense controversy about the frequency of cleanroom air sampling that is required to prevent the contamination of sterile preparations. For compounders who must purchase an air sampler to use in the cleanroom, choices abound. Included in this article are a review of United States Pharmacopeia-National Formulary requirements that pertain to air sampling, a discussion of how recent revision to Chapter 797 affect air sampling and patient safety, and, for easy reference, a table that features specifications for various models of microbial air samplers.

  17. Tissue kerma vs distance relationships for initial nuclear radiation from the atomic devices detonated over Hiroshima and Nagasaki

    International Nuclear Information System (INIS)

    Initial nuclear radiation is comprised of prompt neutrons and prompt primary gammas from an exploding nuclear device, prompt secondary gammas produced by neutron interactions in the environment, and delayed neutrons and delayed fission-product gammas from the fireball formed after the nuclear device explodes. These various components must all be considered in establishing tissue kerma vs distance relationships which describe the decrease of initial nuclear radiation with distance in Hiroshima and in Nagasaki. The tissue kerma at ground evel from delayed fission-product gammas and delayed neutrons was investigated using the NUIDEA code developed by Science Applications, Inc. This code incorporates very detailed models which can take into account such features as the rise of the fireball, the rapid radioactive decay of fission products in it, and the perturbation of the atmosphere by the explosion. Tissue kerma vs distance relationships obtained by summing results of these current state-of-the-art calculations will be discussed. Our results clearly show that the prompt secondary gammas and delayed fission-product gammas are the dominant components of total tissue kerma from initial nuclear radiation in the cases of the atomic (or pure-fission) devices detonated over Hiroshima and Nagasaki

  18. Basis to demonstrate compliance with the National Emission Standards for Hazardous Air Pollutants for the Stand-off Experiments Range

    Energy Technology Data Exchange (ETDEWEB)

    Michael Sandvig

    2011-01-01

    The purpose of this report is to provide the basis and the documentation to demonstrate general compliance with the National Emission Standard for Hazardous Air Pollutants (NESHAPS) 40 CFR 61 Subpart H, “National Emission Standards for Emissions of Radionuclides Other Than Radon from Department of Energy Facilities,” (the Standard) for outdoor linear accelerator operations at the Idaho National Laboratory (INL) Stand-off Experiments Range (SOX). The intent of this report is to inform and gain acceptance of this methodology from the governmental bodies regulating the INL.

  19. Analysis of chemistry textbook content and national science education standards in terms of air quality-related learning goals

    Science.gov (United States)

    Naughton, Wendy

    In this study's Phase One, representatives of nine municipal agencies involved in air quality education were interviewed and interview transcripts were analyzed for themes related to what citizens need to know or be able to do regarding air quality concerns. Based on these themes, eight air quality Learning Goal Sets were generated and validated via peer and member checks. In Phase Two, six college-level, liberal-arts chemistry textbooks and the National Science Education Standards (NSES) were analyzed for congruence with Phase One learning goals. Major categories of desired citizen understandings highlighted in agency interviews concerned air pollution sources, impact, detection, and transport. Identified cognitive skills focused on information-gathering and -evaluating skills, enabling informed decision-making. A content match was found between textbooks and air quality learning goals, but most textbooks fail to address learning goals that remediate citizen misconceptions and inabilities---particularly those with a "personal experience" focus. A partial match between NSES and air quality learning goals was attributed to differing foci: Researcher-derived learning goals deal specifically with air quality, while NSES focus is on "fundamental science concepts," not "many science topics." Analysis of findings within a situated cognition framework suggests implications for instruction and NSES revision.

  20. Characterization tests of a homemade ionization chamber in mammography standard radiation beams

    International Nuclear Information System (INIS)

    A mammography homemade ionization chamber was developed to be applied for mammography energy range dosimetry. This chamber has a sensitive volume of 6 cm3 and is made of a Lucite body and graphite coated collecting electrode. Characteristics such as saturation, ion collection efficiency, linearity of chamber response versus air kerma rate and energy dependence were determined. The results obtained with the mammography homemade ionization chamber are within the limits stated in international recommendations. This chamber can be used in quality control programs in the diagnostic radiology area. All measurements were carried out at the Calibration Laboratory of IPEN. - Highlights: • We constructed a mammography homemade ionization chamber. It was submitted to standard mammography X-rays beam qualities. • The results obtained showed good agreement with international standards. • This chamber can be used in quality control programs of diagnostic radiology area

  1. Technical comments on EPA`s proposed revisions to the National Ambient Air Quality Standard for particulate matter

    Energy Technology Data Exchange (ETDEWEB)

    Lipfert, F.W.

    1997-03-01

    The US Environmental Protection Agency (EPA) has proposed new ambient air quality standards specifically for fine particulate matter, regulating concentrations of particles with median aerodynamic diameters less than 2.5 {mu}m (PM{sub 2.5}). Two new standards have been proposed: a maximum 24-hr concentration that is intended to protect against acute health effects, and an annual concentration limit that is intended to protect against longer-term health effects. EPA has also proposed a slight relaxation of the 24-hr standard for inhalable particles (PM{sub 10}), by allowing additional exceedances each year. Fine particles are currently being indirectly controlled by means of regulations for PM{sub 10} and TSP, under the Clean Air Act of 1970 and subsequent amendments. Although routine monitoring of PM{sub 2.5} is rare and data are sparse, the available data indicate that ambient concentrations have been declining at about 6% per year under existing regulations.

  2. A new standard cylindrical graphite-walled ionization chamber for dosimetry in 60Co beams at calibration laboratories

    Science.gov (United States)

    Neves, Lucio P.; Perini, Ana P.; Caldas, Linda V. E.

    2014-11-01

    60Co sources are used mostly at dosimetry laboratories for calibration of ionization chambers utilized for radiotherapy dosimetry, mainly in those laboratories where there is no linear accelerator available. In this work, a new cylindrical ionization chamber was developed and characterized to be used as a reference dosimeter at the Calibration Laboratory of the IPEN. The characterization tests were performed according to the IEC 60731 standard, and all tests presented results within its recommended limits. Furthermore, the correction factors for the wall, stem, central collecting electrode, nonaxial uniformity and the mass-energy absorption coefficient were determined using the EGSnrc Monte Carlo code. The air kerma rate determined with this new dosimeter was compared to the one obtained with the IPEN standard, presenting a difference of 1.5%. Therefore, the new ionization chamber prototype developed and characterized in this work presents potential use as a primary standard dosimeter at radiation metrology laboratories.

  3. Effective atomic number, electron density and kerma of gamma radiation for oxides of lanthanides

    Indian Academy of Sciences (India)

    R S Niranjan; B Rudraswamy; N Dhananjaya

    2012-03-01

    An attempt has been made to estimate the effective atomic number, electron density (0.001 to 105 MeV) and kerma (0.001 to 20 MeV) of gamma radiation for a wide range of oxides of lanthanides using mass attenuation coefficient from WinXCom and mass energy absorption coefficient from Hubbell and Seltzer. The values of these parameters have been found to change with energy for different oxides of lanthanides. The lanthanide oxides find remarkable applications in the field of medicine, biology, nuclear engineering and space technology. Nano-oxides of lanthanide find applications in display and lighting industry.

  4. OpenAIRE Guidelines for CRIS Managers: Supporting Interoperability of Open Research Information through Established Standards

    DEFF Research Database (Denmark)

    Houssos, Nikos; Jörg, Brigitte; Dvořák, Jan;

    2014-01-01

    OpenAIRE is the European infrastructure enabling researchers to comply with the European Union requirements for Open Access to research results. OpenAIRE collects metadata from data sources across Europe and beyond and defines interoperability guidelines to assist providers in exposing their...... information in a way that is compatible with OpenAIRE. This contribution focuses on a specific type of data source, CRIS systems, and the respective OpenAIRE guidelines, based on CERIF XML. A range of issues, spanning different aspects of information representation and exchange, needed to be addressed by the...

  5. CITY DEVELOPMENT FOR KEEPING POLLUTANT CONCENTRATIONS FROM MOTOR VEHICLES IN RESIDENTIAL AREAS IN ACCORDANCE WITH AIR QUALITY STANDARDS

    Directory of Open Access Journals (Sweden)

    Владимир Васильевич Балакин

    2016-02-01

    Full Text Available The dependency of carbon monoxide concentrations on wind speed has been obtained in the field studies. It is used in determining optimum ventilation modes for street space to ensure keeping the content of the toxic components from automobile exhaust in accordance with public health standards.Environmental basis for development optimization for busy primary streets has been provided to avoid dangerous levels of ambient air pollution with automobile emissions.Positive effect on air quality from belt roads, bypass roads and pedestrian areas situated in city centers is noted.

  6. Addition of PM2.5 into the National Ambient Air Quality Standards of China and the Contribution to Air Pollution Control: The Case Study of Wuhan, China

    Directory of Open Access Journals (Sweden)

    Mingqing You

    2014-01-01

    Full Text Available PM2.5 has gradually become a major environmental problem of China with its rapid economic development, urbanization, and increasing of motor vehicles. Findings and awareness of serious PM2.5 pollution make the PM2.5 a new criterion pollutant of the Chinese National Ambient Air Quality Standard (NAAQS revised in 2012. The 2012 NAAQS sets the PM2.5 concentrate limitation with the 24-hour average value and the annual mean value. Wuhan is quite typical among central and southern China in climate, economy, development level, and energy consumption. The data are cited from the official website of Wuhan Environmental Protection Bureau and cover the period from 1 January to 30 June 2013. The data definitely confirm the existence of serious PM2.5 pollution in Wuhan and indicate that the addition of PM2.5 as a criterion pollutant significantly brings down the attainment rate of air quality. The example of Wuhan reveals that local governments should take measures to reduce the emission of PM2.5 if it affects the attainment rate and the performance evaluation value of air quality. The main contribution of 2012 NAAQS is that it brings down the attainment rate of the air quality and forces local governmental officials to take the measures accordingly.

  7. A review on test procedure, energy efficiency standards and energy labels for room air conditioners and refrigerator-freezers

    Energy Technology Data Exchange (ETDEWEB)

    Mahlia, T.M.I.; Saidur, R. [Department of Mechanical Engineering, University of Malaya, 50603 Kuala Lumpur (Malaysia)

    2010-09-15

    Air conditioners and refrigerator-freezers are major energy users in a household environment and hence efficiency improvement of these appliances can be considered as an important step to reduce their energy consumption along with environmental pollution prevention. Energy efficiency standards and labels are commonly used tools to reduce the energy uses for household appliances for many countries around the world. The first step towards adopting energy efficiency standards is to establish a test procedure for rating and testing of an appliance. It may be mentioned that an energy test procedure is the technical foundation for energy efficiency standards, energy labels, and other related programs. This paper reviews requirements and specifications of various international test standards for testing and rating of room air conditioners and refrigerators. A review on the development of the energy efficiency standards has been provided as well. Finally, energy labels that provide some useful information for identifying energy efficient products have been reviewed for these appliances. It may be stated that the review will be useful for the developing countries who wish to develop these energy savings strategies. It is also expected to be useful to revise the existing strategies for a few selected countries who already implemented these strategies earlier. (author)

  8. 77 FR 555 - National Emissions Standards for Hazardous Air Pollutants From Secondary Lead Smelting

    Science.gov (United States)

    2012-01-05

    ...) emissions limits and a plastic separation work practice standard to prevent dioxin formation. Finalizing... plastics from automotive batteries to prevent dioxin emissions, the addition of work practice standards to... January 5, 2012 Part II Environmental Protection Agency 40 CFR Part 63 National Emissions Standards...

  9. 77 FR 23399 - National Emission Standards for Hazardous Air Pollutants From Coal- and Oil-Fired Electric...

    Science.gov (United States)

    2012-04-19

    ... AGENCY 40 CFR Parts 60 and 63 RIN 2060-AP52 and 2060-AR31 National Emission Standards for Hazardous Air..., 2012 (77 FR 9304). DATES: Effective date: April 19, 2012. FOR FURTHER INFORMATION CONTACT: For the.../GWh). lb/GWh). 1 lb/GWh). lb/GWh). 3 lb/GWh). Arsenic, As 1.1E0 lb/TBtu (2.0E-2 1.5E0 lb/TBtu...

  10. Estándares para el Sistema de Bibliotecas de la Universidad de Buenos Aires Standards for the Universidad de Buenos Aires Libraries System

    Directory of Open Access Journals (Sweden)

    Elsa Elena Elizalde

    2009-06-01

    Full Text Available La Coordinación General del Sistema de Bibliotecas y de Información -SISBI- de la Universidad de Buenos Aires propuso la conformación de un Grupo de Trabajo para el estudio y la definición de los requerimientos para un adecuado nivel de prestación de los servicios de todas sus bibliotecas. Estos estándares externos completarán y actualizarán los «Lineamientos para una Política Bibliotecaria de la Universidad de Buenos Aires (Resolución CS Nº 222/94». El objetivo del conjunto de criterios que representan estos Estándares para el Sistema de Bibliotecas de la UBA, es que éstas cuenten con una herramienta base que les permita tomar decisiones concernientes a la planificación y administración de los servicios bibliotecarios. Independientemente, se espera que cada Biblioteca defina sus estándares internos de tiempo, calidad, cantidad y costos que reflejen las metas y objetivos de cada Unidad Académica en particular. Estos estándares contemplan: Aspectos organizativos de la Biblioteca Universitaria y Principios Generales del SISBI; Infraestructura Edilicia y Tecnológica; Recursos Humanos; Servicios y/o Productos; Desarrollo de la colección; Procesos Técnicos; Presupuesto; Evaluación y Gestión de la Calidad e Innovación; Prevención y Conservación; entre otros.The General Coordination of the Sistema de Bibliotecas y de Información- SISBI- of the Universidad de Buenos Aires proposed the creation of a Work Group for the study and definition of the requirements for a proper provision level of all libraries services. Those external standards will complement and update the «Guidelines for a Library Policy of the Universidad de Buenos Aires (Resolution N° 222/94». The aim of the whole criteria that represent the Standards for the UBA Libraries System is that they have a basic tool that allow them to take decisions on planning and administration of library services. Separately, it is expected that each Library defines its

  11. Air

    Science.gov (United States)

    ... house) Industrial emissions (like smoke and chemicals from factories) Household cleaners (spray cleaners, air fresheners) Car emissions (like carbon monoxide) *All of these things make up “particle pollution.” They mostly come from cars, trucks, buses, and ...

  12. Standard Test Method for Water Penetration of Flat Plate Solar Collectors by Uniform Static Air Pressure Difference

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1986-01-01

    1.1 This test method covers the determination of the resistance of flat plate solar collectors to water penetration when water is applied to their outer surfaces with a static air pressure at the outer surface higher than the pressure at the interior of the collector. 1.2 This test method is applicable to any flat plate solar collector. 1.3 The proper use of this test method requires a knowledge of the principles of pressure and deflection measurement. 1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific precautionary information is contained in Section 6.

  13. 76 FR 72769 - National Emissions Standards for Hazardous Air Pollutants: Mineral Wool Production and Wool...

    Science.gov (United States)

    2011-11-25

    ... process units: a cupola furnace for melting the mineral charge; a blow chamber in which air and, in some..., hydrogen fluoride and hydrochloric acid for cupolas; add combined collection and curing processes as new... acid and particulate matter for glass- melting furnaces at major sources; revised emissions limits...

  14. 78 FR 22369 - National Emissions Standards for Hazardous Air Pollutants: Mineral Wool Production and Wool...

    Science.gov (United States)

    2013-04-15

    ... attenuation GP General Provisions HAP hazardous air pollutants ] HCl Hydrogen chloride HF Hydrogen fluoride HI... area and major sources? Glass-melting furnaces emit metal HAP (chromium, cadmium, beryllium, manganese... contaminated cullet i.e., crushed recycled glass (64 FR 31695 (June 14, 1999)). As shown in Table 2 below,...

  15. 76 FR 76259 - National Emissions Standards for Hazardous Air Pollutants: Primary Aluminum Reduction Plants

    Science.gov (United States)

    2011-12-06

    ... facilities are carbonyl sulfide (COS), hydrogen fluoride (HF), and polycyclic organic matter (POM... unregulated emissions (i.e., carbonyl sulfide (COS) emissions from new and existing potlines and polycyclic... acute exposure guideline levels AERMOD air dispersion model used by the HEM-3 model AMOS ample margin...

  16. 76 FR 14636 - National Emission Standards for Hazardous Air Pollutants: Primary Lead Smelting

    Science.gov (United States)

    2011-03-17

    ... Air Pollutants for Primary Lead Smelting (76 FR 9410). The EPA is extending the deadline for written...-2004-0305, by one of the following methods: http://www.regulations.gov : Follow the on-line... the use of special characters, any form of encryption, and be free of any defects or viruses....

  17. 76 FR 57913 - Amendments to National Emission Standards for Hazardous Air Pollutants for Area Sources: Plating...

    Science.gov (United States)

    2011-09-19

    ... Air Pollutants for Area Sources: Plating and Polishing'' which was published on June 20, 2011 (76 FR... direct final rule published at 76 FR 35750 on June 20, 2011. ADDRESSES: Docket: All documents in the... (76 FR 35806) published on the same day as a direct final rule, EPA will not institute a...

  18. Standard specification for high efficiency particulate air filters. Revision No. 2

    International Nuclear Information System (INIS)

    This specification covers the requirements for four types and four sizes of high efficiency particulate air filters, assembled with or without separators and gaskets. Types include Fire Resistant and Moisture Resistant; Hydrogen Fluoride Fume (HF) Resistant; Fire Resistant and Moisture Resistant and Chemical Resistant; and Fire Resistant and Moisture Resistant, High Temperature and High Humidity

  19. 76 FR 80597 - National Emission Standards for Hazardous Air Pollutants for Major Sources: Industrial...

    Science.gov (United States)

    2011-12-23

    ...., distillate oil, biodiesel, or vegetable oil) and less than 10 percent coal and less than 10 percent biomass... exchange in various areas of air pollution control. ] II. Background Information On March 21, 2011, the EPA... burns at least 10 percent biomass on an annual average heat input \\1\\ basis, the unit is in one of...

  20. 77 FR 16987 - National Emission Standards for Hazardous Air Pollutants: Secondary Aluminum Production

    Science.gov (United States)

    2012-03-23

    ... for hazardous air pollutants for secondary aluminum production (77 FR 8576). The EPA is extending the... the proposed rule published February 14, 2012, (77 FR 8576) is being extended for 14 days to April 13... Aluminum Production AGENCY: Environmental Protection Agency (EPA). ACTION: Notice of extension of...

  1. 76 FR 22565 - National Emission Standards for Hazardous Air Pollutant Emissions: Group I Polymers and Resins...

    Science.gov (United States)

    2011-04-21

    ... Emissions: Group I Polymers and Resins were promulgated on September 5, 1996 (62 FR 46925), and codified at... Hazardous Air Pollutant Emissions: Group I Polymers and Resins; Marine Tank Vessel Loading Operations... Polymers and Resins; Marine Tank Vessel Loading Operations; Pharmaceuticals Production; and the...

  2. 76 FR 15553 - National Emission Standards for Hazardous Air Pollutants for Area Sources: Industrial, Commercial...

    Science.gov (United States)

    2011-03-21

    ... on boiler inspector data-bases from 13 states. The boiler inspector data-bases include steam boilers... Hazardous Air Pollutants for Area Sources: Industrial, Commercial, and Institutional Boilers; Final Rule #0... Pollutants for Area Sources: Industrial, Commercial, and Institutional Boilers AGENCY:...

  3. 76 FR 42613 - National Emission Standards for Hazardous Air Pollutants for Polyvinyl Chloride and Copolymers...

    Science.gov (United States)

    2011-07-19

    ... Polyvinyl Chloride and Copolymers Production; Extension of Comment Period AGENCY: Environmental Protection... for Hazardous Air Pollutants for Polyvinyl Chloride and Copolymers Production is being extended for 14... extend the public comment period for the May 20, 2011, Proposed Polyvinyl Chloride and...

  4. Consumer life-cycle cost impacts of energy-efficiency standards for residential-type central air conditioners and heat pumps

    International Nuclear Information System (INIS)

    In support of the federal government's efforts to raise the minimum energy-efficiency standards for residential-type central air conditioners and heat pumps, a consumer life-cycle cost (LCC) analysis was conducted to demonstrate the economic impacts on individual consumers from revisions to the standards. LCC is the consumer's cost of purchasing and installing an air conditioner or heat pump and operating the unit over its lifetime. The LCC analysis is conducted on a nationally representative sample of air conditioner and heat pump consumers resulting in a distribution of LCC impacts showing the percentage of consumers that are either benefiting or being burdened by increased standards. Relative to the existing minimum efficiency standard of 10 SEER, the results show that a majority of split system air conditioner and heat pump consumers will either benefit or be insignificantly impacted by increased efficiency standards of up to 13 SEER

  5. Determination of the air attenuation and electronic loss for the free air concentric cylinders ionization chamber; Determinacao da atenuacao do ar e perda eletronica para a camara de ionizacao de ar livre de cilindros concentricos

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Hebert Pinto Silveira de

    2010-07-01

    Along the latest years, the LNMRI has been proceeding a continuous research work with a concentric cylinders type free air ionizing chamber (VICTOREEN, model 481), aiming to establish it as a new national standard, and, as a consequence, replace the worldwide accepted secondary standard, calibrated by PTB. Taking into account that the absolute determination of kerma in air with a free air ionizing chamber implies the acquirement of a number of correction factors. The main objective of the present work comprises the determination of the two factors, specifically, electronic loss (k{sub e}) and air attenuation (k{sub a}). The correction factors were obtained through mammography qualities reference spectrum, using Monte Carlo simulation method. The Penelope code was used in the simulation procedures. Simulations took place in two stages, the acquirement of specters related to the qualities of interest (mammography) with the x ray tube (Pantak, model HF160 e Panalytical, model XRF window), and the free-air ionization chamber. The data were compared to those related to the BIPM chamber, to electronic loss were not detected. The comparison between air attenuation factors was obtained data bellow 0.13%. (author)

  6. Progress towards Managing Residential Electricity Demand: Impacts of Standards and Labeling for Refrigerators and Air Conditioners in India

    Energy Technology Data Exchange (ETDEWEB)

    McNeil, Michael A.; Iyer, Maithili

    2009-05-30

    The development of Energy Efficiency Standards and Labeling (EES&L) began in earnest in India in 2001 with the Energy Conservation Act and the establishment of the Indian Bureau of Energy Efficiency (BEE). The first main residential appliance to be targeted was refrigerators, soon to be followed by room air conditioners. Both of these appliances are of critical importance to India's residential electricity demand. About 15percent of Indian households own a refrigerator, and sales total about 4 million per year, but are growing. At the same time, the Indian refrigerator market has seen a strong trend towards larger and more consumptive frost-free units. Room air conditioners in India have traditionally been sold to commercial sector customers, but an increasing number are going to the residential sector. Room air conditioner sales growth in India peaked in the last few years at 20percent per year. In this paper, we perform an engineering-based analysis using data specific to Indian appliances. We evaluate costs and benefits to residential and commercial sector consumers from increased equipment costs and utility bill savings. The analysis finds that, while the BEE scheme presents net benefits to consumers, there remain opportunities for efficiency improvement that would optimize consumer benefits, according to Life Cycle Cost analysis. Due to the large and growing market for refrigerators and air conditioners in India, we forecast large impacts from the standards and labeling program as scheduled. By 2030, this program, if fully implemented would reduce Indian residential electricity consumption by 55 TWh. Overall savings through 2030 totals 385 TWh. Finally, while efficiency levels have been set for several years for refrigerators, labels and MEPS for these products remain voluntary. We therefore consider the negative impact of this delay of implementation to energy and financial savings achievable by 2030.

  7. Information draft on the development of air standards for n-heptane

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-01-01

    Heptane is a colourless, volatile, flammable liquid with nine isomers, the most common being n-heptane, which has a paraffinic odour. It is an ingredient in gasoline, rubber solvents, naphtha and other petroleum solvents. It occurs almost entirely in the vapour phase, where it is degraded primarily by reaction with photochemically-produced hydroxyl radicals. Short-term exposure to n-heptane at relatively low concentration resulted in vertigo and loss of coordination. Exposure to high concentration for less than 40 minutes induced prostration and loss of reflexes prior to convulsion and death. Average ambient air concentration for n-heptane in Ontario between 1988 and 1995 was 0.81 microgram/cubic meter, as measured by Environment Canada. Currently, Ontario does not have air quality criterion for n-heptane. A review of pertinent literature from world-wide sources revealed that only the states of Michigan and New York have developed air quality guidelines specifically for n-heptane, based on occupational exposure. No human or animal data was found to be available to assess the carcinogenicity of this compound. 33 refs., 1 tab., appendix.

  8. ETS levels in hospitality environments satisfying ASHRAE standard 62-1989: "ventilation for acceptable indoor air quality"

    Science.gov (United States)

    Moschandreas, D. J.; Vuilleumier, K. L.

    Prior to this study, indoor air constituent levels and ventilation rates of hospitality environments had not been measured simultaneously. This investigation measured indoor Environmental Tobacco Smoke-related (ETS-related) constituent levels in two restaurants, a billiard hall and a casino. The objective of this study was to characterize ETS-related constituent levels inside hospitality environments when the ventilation rates satisfy the requirements of the ASHRAE 62-1989 Ventilation Standard. The ventilation rate of each selected hospitality environment was measured and adjusted. The study advanced only if the requirements of the ASHRAE 62-1989 Ventilation Standard - the pertinent standard of the American Society of Heating, Refrigeration and Air Conditioning Engineers - were satisfied. The supply rates of outdoor air and occupant density were measured intermittently to assure that the ventilation rate of each facility satisfied the standard under occupied conditions. Six ETS-related constituents were measured: respirable suspended particulate (RSP) matter, fluorescent particulate matter (FPM, an estimate of the ETS particle concentrations), ultraviolet particulate matter (UVPM, a second estimate of the ETS particle concentrations), solanesol, nicotine and 3-ethenylpyridine (3-EP). ETS-related constituent levels in smoking sections, non-smoking sections and outdoors were sampled daily for eight consecutive days at each hospitality environment. This study found that the difference between the concentrations of ETS-related constituents in indoor smoking and non-smoking sections was statistically significant. Differences between indoor non-smoking sections and outdoor ETS-related constituent levels were identified but were not statistically significant. Similarly, differences between weekday and weekend evenings were identified but were not statistically significant. The difference between indoor smoking sections and outdoors was statistically significant. Most

  9. Preparation of standard mixtures of gas hydrocarbons in air by the diffusion dilution method

    International Nuclear Information System (INIS)

    An original diffusion system able to produce continuously gaseous samples is described. This system can generate samples with concentrations of benzene in air from 0.1 to 1 ppm a reproducible way. The diffusion dilution method used Is also studied. The use of this diffusion system has been extended to the preparation of binary mixtures (benzene-toluene). Whit a secondary dilution device is possible preparing these mixtures over a wide range of concentrations (0.11 to 0.04 ppm for benzene and 0.06 to 0.02 for toluene). (Author) 7 refs

  10. The effects of ambient conditions on the calibration of air flow plate standards

    Directory of Open Access Journals (Sweden)

    Miao Qian

    2013-01-01

    Full Text Available The volume flow rate measured by air flow plate is influenced by the ambient conditions during the calibration. A series of numerical examples are conducted for the relationship and the outcomes demonstrated that the calibration is quite sensitive to the atmospheric pressure and the ambient temperature, but insensitive to relative humidity. The experiment model has been applied to calibration results with wide ranging ambient conditions. In conclusion, the results of this study demonstrate the benefits to calibration data of minimizing the effects of ambient conditions.

  11. 78 FR 37133 - National Emission Standards for Hazardous Air Pollutants From Petroleum Refineries

    Science.gov (United States)

    2013-06-20

    ...) on August 18, 1995 (60 FR 43620). These standards are commonly referred to as the ``Refinery MACT 1... leaks and closed vent system and control devices (see 77 FR 17898). We believe it is appropriate to..., letter to the EPA. As described in detail in the January 6, 2012, proposal (see 77 FR 964), we denied...

  12. 76 FR 2832 - National Emission Standards for Hazardous Air Pollutants From the Portland Cement Manufacturing...

    Science.gov (United States)

    2011-01-18

    ... amendments? On September 9, 2010 (75 FR 54970), EPA issued final amendments to National Emission Standards... production if significant adverse comments are filed. II. What are the changes to the final rules (75 FR... FR at 54993), and never discussed or otherwise suggested (in either the proposed or final rule)...

  13. 78 FR 24073 - Reconsideration of Certain New Source Issues: National Emission Standards for Hazardous Air...

    Science.gov (United States)

    2013-04-24

    ... Manufacturing Industry and Standards of Performance for Portland Cement Plants, 78 FR 10014 (February 12, 2013... (MACT) Floor Analysis for Coal- and Oil-fired Electric Utility Steam Generating Units for Final Rule... oil and the rule may not apply depending on the extent of natural gas usage. The EPA proposed that...

  14. 77 FR 33811 - National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion...

    Science.gov (United States)

    2012-06-07

    ... a deviation of voltage or frequency of 5 percent or more below standard voltage or frequency. During... to a potential electrical blackout, such as unusually low frequency, equipment overload, capacity or... emergency engines to only operate during true emergencies or when voltage or frequency varies...

  15. 75 FR 14368 - Energy Conservation Standards for Residential Central Air Conditioners and Heat Pumps: Public...

    Science.gov (United States)

    2010-03-25

    ... conditioners and heat pumps. 66 FR 7170. The amended standards would have increased the minimum SEER to 13 for... and heat pumps; the analytical framework, models, and tools that DOE is using to evaluate amended... Heat Pumps, EERE-2008-BT- STD-0006, 1000 Independence Avenue, SW., Washington, DC 20585-0121....

  16. 76 FR 46083 - Secondary National Ambient Air Quality Standards for Oxides of Nitrogen and Sulfur

    Science.gov (United States)

    2011-08-01

    ... considered. Discussion of the structures and basic elements of the current NO 2 and SO 2 secondary standards... relevant data so as to enhance the Agency's understanding of the degree of protectiveness that a new multi... provide any technical information and/or data that you used. If you estimate potential costs or...

  17. 77 FR 55698 - National Emission Standards for Hazardous Air Pollutants From the Pulp and Paper Industry

    Science.gov (United States)

    2012-09-11

    ... for the pulp and paper industry was promulgated on April 15, 1998 (63 FR 18504). The standards are... uncertainties discussed in the proposal preamble (76 FR 81338-40), the risks from the pulp and paper source... Environmental Justice EPA Environmental Protection Agency ERT Electronic Reporting Tool FR Federal Register...

  18. Design and preliminary test of a free-air ionization chamber for low-energy X-ray

    Institute of Scientific and Technical Information of China (English)

    吴金杰; 杨元第; 王培玮; 陈靖; 柳加成

    2011-01-01

    A free-air ionization chamber in low-energy X-ray has been designed and manufactured at the National Institute of Metrology (NIM, China) according to the defination of air-kerma. The results of a preliminary test show that the leakage current of ionizatio

  19. Hanford Site radionuclide national emission standards for hazardous air pollutants registered stack source assessment

    Energy Technology Data Exchange (ETDEWEB)

    Davis, W.E.; Barnett, J.M.

    1994-07-01

    On February 3, 1993, the US Department of Energy, Richland Operations Office received a Compliance Order and Information Request from the Director of the Air and Toxics Division of the US Environmental Protection Agency,, Region 10. The Compliance Order requires the Richland Operations Office to evaluate all radionuclide emission points at the Hanford Site . The evaluation also determined if the effective dose equivalent from any of these stack emissions exceeded 0.1 mrem/yr, which will require the stack to have continuous monitoring. The result of this assessment identified a total of 16 stacks as having potential emissions that,would cause an effective dose equivalent greater than 0.1 mrem/yr.

  20. Hanford Site radionuclide national emission standards for hazardous air pollutants unregistered stack (power exhaust) source assessment

    Energy Technology Data Exchange (ETDEWEB)

    Davis, W.E.

    1994-08-04

    On February 3, 1993, the US Department of Energy, Richland Operations Office received a Compliance Order and Information Request from the Director of the Air and Toxics Division of the US Environmental Protection Agency, Region 10. The Compliance Order requires the Richland Operations Office to evaluate all radionuclide emission points at the Hanford Site to determine which are subject to continuous emission measurement requirements in 40 Code of Federal Regulations (CFR) 61, Subpart H, and to continuously measure radionuclide emissions in accordance with 40 CFR 61.93. This evaluation provides an assessment of the 39 unregistered stacks, under Westinghouse Hanford Company`s management, and their potential radionuclide emissions, i.e., emissions with no control devices in place. The evaluation also determined if the effective dose equivalent from any of these stack emissions exceeded 0.1 mrem/yr, which will require the stack to have continuous monitoring. The result of this assessment identified three stacks, 107-N, 296-P-26 and 296-P-28, as having potential emissions that would cause an effective dose equivalent greater than 0.1 mrem/yr. These stacks, as noted by 40 CFR 61.93, would require continuous monitoring.

  1. 1996 Idaho National Engineering and Environmental Laboratory (INEEL) National Emissions Standards for Hazardous Air Pollutants (NESHAPs) -- Radionuclides. Annual report

    International Nuclear Information System (INIS)

    Under Section 61.94 of Title 40, Code of Federal Regulations (CFR), Part 61, Subpart H, ''National Emission Standards for Emissions of Radionuclides Other Than Radon From Department of Energy Facilities,'' each Department of Energy (DOE) facility must submit an annual report documenting compliance. This report addresses the Section 61.94 reporting requirements for operations at the Idaho National Engineering and Environmental Laboratory (INEEL) for calendar year (CY) 1996. The Idaho Operations Office of the DOE is the primary contact concerning compliance with the National Emission Standards for Hazardous Air Pollutants (NESHAPs) at the INEEL. For calendar year 1996, airborne radionuclide emissions from the INEEL operations were calculated to result in a maximum individual dose to a member of the public of 3.14E-02 mrem (3.14E-07 Sievert). This effective dose equivalent (EDE) is well below the 40 CFR 61, Subpart H, regulatory standard of 10 mrem per year (1.0E-04 Sievert per year)

  2. Dependence with air density of the response of the PTW SourceCheck ionization chamber for low energy brachytherapy sources

    Energy Technology Data Exchange (ETDEWEB)

    Tornero-López, Ana M.; Guirado, Damián; Ruiz-Arrebola, Samuel [Servicio de Radiofísica y Protección Radiológica, Hospital Universitario San Cecilio, E-18012 Granada (Spain); Perez-Calatayud, Jose [Servicio de Radioterapia, Unidad de Radiofísica, Hospital Universitario y Politécnico La Fe, E-46026 Valencia (Spain); Simancas, Fernando; Lallena, Antonio M. [Departamento de Física Atómica, Molecular y Nuclear, Universidad de Granada, E-18071 Granada (Spain); Gazdic-Santic, Maja [Department of Medical Physics and Radiation Safety, Clinical Centre of Sarajevo University, 71000 Sarajevo (Bosnia and Herzegovina)

    2013-12-15

    Purpose: Air-communicating well ionization chambers are commonly used to assess air kerma strength of sources used in brachytherapy. The signal produced is supposed to be proportional to the air density within the chamber and, therefore, a density-independent air kerma strength is obtained when the measurement is corrected to standard atmospheric conditions using the usual temperature and pressure correction factor. Nevertheless, when assessing low energy sources, the ionization chambers may not fulfill that condition and a residual density dependence still remains after correction. In this work, the authors examined the behavior of the PTW 34051 SourceCheck ionization chamber when measuring the air kerma strength of {sup 125}I seeds.Methods: Four different SourceCheck chambers were analyzed. With each one of them, two series of measurements of the air kerma strength for {sup 125}I selectSeed{sup TM} brachytherapy sources were performed inside a pressure chamber and varying the pressure in a range from 747 to 1040 hPa (560 to 780 mm Hg). The temperature and relative humidity were kept basically constant. An analogous experiment was performed by taking measurements at different altitudes above sea level.Results: Contrary to other well-known ionization chambers, like the HDR1000 PLUS, in which the temperature-pressure correction factor overcorrects the measurements, in the SourceCheck ionization chamber they are undercorrected. At a typical atmospheric situation of 933 hPa (700 mm Hg) and 20 °C, this undercorrection turns out to be 1.5%. Corrected measurements show a residual linear dependence on the density and, as a consequence, an additional density dependent correction must be applied. The slope of this residual linear density dependence is different for each SourceCheck chamber investigated. The results obtained by taking measurements at different altitudes are compatible with those obtained with the pressure chamber.Conclusions: Variations of the altitude and

  3. National Emission Standards for Hazardous Air Pollutants Calendar Year 2001; TOPICAL

    International Nuclear Information System (INIS)

    The Nevada Test Site (NTS) is operated by the U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Operations Office (NNSA/NV) as the site for nuclear weapons testing, now limited to readiness activities, experiments in support of the national Stockpile Stewardship Program, and the activities listed below. Located in Nye County, Nevada, the site's southeast corner is about 88 km (55 mi) northwest of the major population center, Las Vegas, Nevada. The NTS covers about 3,561 km2 (1,375 mi2), an area larger than Rhode Island. Its size is 46 to 56 km (28 to 35 mi) east to west and from 64 to 88 km (40 to 55 mi) north to south. The NTS is surrounded, except on the south side, by public exclusion areas (Nellis Air Force Range[NAFR]) that provide another 24 to 104 km (15 to 65 mi) between the NTS and public lands (Figure 1.0). The NTS is characterized by desert valley and Great Basin mountain topography, with a climate, flora, and fauna typical of the southwest deserts. Population density within 150 km (93 mi) of the NTS is only about 0.2 persons per square kilometer, excluding the Las Vegas area. Restricted access, low population density in the surrounding area, and extended wind transport times are advantageous factors for the activities conducted at the NTS. Surface waters are scarce on the NTS, and slow-moving groundwater is present hundreds to thousands of feet below the land surface. The sources of radionuclides include current and previous activities conducted on the NTS (Figure 2.0). The NTS was the primary location for testing of nuclear explosives in the Continental U.S. between 1951 and 1992. Historical testing above or at ground surface has included (1) atmospheric testing in the 1950s and early 1960s, (2) earth-cratering experiments, and (3) open-air nuclear reactor and rocket engine testing. Since the mid-1950s, testing of nuclear explosive devices has occurred underground in drilled vertical holes or in mined tunnels (DOE 1996a

  4. Radiation Protection. Measurement of radioactivity in the environment - Air- radon 222. A proposed ISO standard.

    Science.gov (United States)

    Gillmore, G.; Woods, M.

    2009-04-01

    this work item is 2011. The ISO document here highlighted is a working draft. ISO is a worldwide federation of national standards bodies. Keywords: radon; international standards; measurement techniques.

  5. 1997 Idaho National Engineering and Environmental Laboratory (INEEL) National Emission Standard for Hazardous Air Pollutants - Radionuclides. Annual report

    International Nuclear Information System (INIS)

    Under Section 61.94 of Title 40, Code of Federal Regulations (CFR), Part 61, Subpart H, National Emission Standards for Emissions of Radionuclides Other Than Radon From Department of Energy Facilities, each Department of Energy (DOE) facility must submit an annual report documenting compliance. This report addresses the Section 61.94 reporting requirements for operations at the Idaho National Engineering and Environmental Laboratory (INEEL) for calendar year (CY) 1997. Section 1 of this report provides an overview of the INEEL facilities and a brief description of the radioactive materials and processes at the facilities. Section 2 identifies radioactive air effluent release points and diffuse sources at the INEEL and actual releases during 1997. Section 2 also describes the effluent control systems for each potential release point. Section 3 provides the methodology and EDE calculations for 1997 INEEL radioactive emissions

  6. Development of standardized air-blown coal gasifier/gas turbine concepts for future electric power systems

    Energy Technology Data Exchange (ETDEWEB)

    Blough, E.; Russell, W.; Leach, J.W.

    1990-08-01

    Computer models have been developed for evaluating conceptual designs of integrated coal gasification combined cycle power plants. An overall system model was developed for performing thermodynamic cycle analyses, and detailed models were developed for predicting performance characteristics of fixed bed coal gasifiers and hot gas clean up subsystem components. The overall system model performs mass and energy balances and does chemical equilibrium analyses to determine the effects of changes in operating conditions, or to evaluate proposed design changes. An existing plug flow model for fixed bed gasifiers known as the Wen II model was revised and updated. Also, a spread sheet model of zinc ferrite sulfur sorbent regeneration subsystem was developed. Parametric analyses were performed to determine how performance depends on variables in the system design. The work was done to support CRS Sirrine Incorporated in their study of standardized air blown coal gasifier gas turbine concepts.

  7. 1997 Idaho National Engineering and Environmental Laboratory (INEEL) National Emission Standards for Hazardous Air Pollutants (NESHAPs) -- Radionuclides annual report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-06-01

    Under Section 61.94 of Title 40, Code of Federal Regulations (CFR), Part 61, Subpart H, National Emission Standards for Emissions of Radionuclides Other Than Radon From Department of Energy Facilities, each Department of Energy (DOE) facility must submit an annual report documenting compliance. This report addresses the Section 61.94 reporting requirements for operations at the Idaho National Engineering and Environmental Laboratory (INEEL) for calendar year (CY) 1997. Section 1 of this report provides an overview of the INEEL facilities and a brief description of the radioactive materials and processes at the facilities. Section 2 identifies radioactive air effluent release points and diffuse sources at the INEEL and actual releases during 1997. Section 2 also describes the effluent control systems for each potential release point. Section 3 provides the methodology and EDE calculations for 1997 INEEL radioactive emissions.

  8. Health effects of tropospheric ozone: Review of recent research findings and their implications to ambient air quality standards

    Energy Technology Data Exchange (ETDEWEB)

    Lippmann, M. (New York Univ. Medical Center, Tuxedo (United States))

    1993-01-01

    The US Environmental Protection Agency (EPA) Administrator proposed (on August 3, 1992) to retain the current National Ambient Air Quality Standard (NAAQS) for ozone (O3) on the basis of data assembled in a draft Criteria Document (1986) and its Addendum (1988) which, together with a draft Staff Paper (1988), received public comment and review comments by the EPA's Clean Air Scientific Advisory Committee (CASAC). This paper summarizes and discusses research findings presented since 1988 which, based on the author's experience as a Chairman of CASAC, are most relevant to the promulgation of a primary (health based) NAAQS for O3. These newer findings include substantial evidence from controlled chamber exposure studies and field studies in natural settings that the current NAAQS contains no margin of safety against short-term effects that the EPA has considered to be adverse. They also include evidence from epidemiologic studies that current ambient exposures are associated with reduced baseline lung function, exacerbation of asthma and premature mortality, as well as evidence from chronic animal exposure studies at concentrations within current ambient peak levels that indicate progressive and persistent lung function and structural abnormalities. The current NAAQS, if retained, may therefore also be inadequate to protect the public from effects resulting from chronic exposure to O3. 96 refs.

  9. Establishment of medium-hard x-ray reference fields for performance tests of radiation measuring instruments based on national standard

    International Nuclear Information System (INIS)

    In the Japanese Industrial Standard, JIS Z 4511 sets the condition of X-ray reference fields to be used for the performance test of radiation measuring instruments for radiation protection. We renewed a X-ray tube of the medium-hard X-ray irradiation device that was damaged in the Facility of Radiation Standards in Nuclear Science Research Institute. Therefore, we established four series of medium-hard X-ray reference fields with quality index of 0.6, 0.7, 0.8 and 0.9 based on JIS Z 4511. In this article, quality of the X-ray fields, X-ray spectra, conversion coefficients to the dose equivalents from Air-kerma were evaluated in the medium-hard X-ray fields produced with X-ray tube voltage ranging from 20 kV to 300 kV, and set about 52 qualities of medium-hard X-ray reference fields based on JIS Z 4511. These X-ray reference fields were well adapted to a setting condition of JIS and precision of conversion factors to various dose equivalents from Air-kerma was good. We also confirmed the soundness of the spectrum of each X-ray quality. As a result, medium-hard X-ray reference fields were established that can provide the dose equivalent standard with good precision and wide range of test energy points and dose rates, for the performance tests such as the energy characteristic and the direction characteristic for various radiation measuring instruments. We clarified these detailed data. (author)

  10. Establishment of standard x-ray qualities to be used in diagnostic level at SSDLs

    International Nuclear Information System (INIS)

    The objective of the present work is to modify x-ray machine (used by the secondary standard dosimetry laboratory in Sudan) to produce x-ray qualities suitable for the calibration at diagnostic level. It based on experimental evaluations. The importance of this study appears in development of protocols to calibrate the instruments used in diagnostic radiology in by good response of the instruments and low cost. In particular, the half value layer (HVL) values for the following qualities 40, 60, 80, 100, 120 and 150 were determined using various attenuation layers. Ionization chamber was used to determine the free air kerma rate at a distance of 100 cm from the x-ray generator. The obtained HVL values were compared with standard values of diagnostic levels. It was observed that the HVL of the present x-ray machine in most qualities are smaller than the standard ones. An approved method (described in the standard IEC 61267) was applied to determine the amount of additional filtration required to meet the standard values. The results show that the available cupper layers were not suitable for this purpose as most of the x-ray was absorbed in the material. Aluminum layers, on the other hand , show good performances to reduce the beams to the desired levels. The amount of additional filtration (from aluminum layers) needed in order to establish standard x-ray qualities to be used in diagnostic level were determined.(Author)

  11. Importance of the neutrons kerma coefficient in the planning of Brachytherapy treatments with Cf-252 sources; Importancia del coeficiente de kerma de neutrones en la planeacion de tratamientos de Braquiterapia con fuentes de Cf-252

    Energy Technology Data Exchange (ETDEWEB)

    Paredes G, L.; Balcazar G, M. [ININ, 52045 Ocoyocac, Estado de Mexico (Mexico); Azorin N, J. [Universidad Autonoma Metropolitana, 09000 Mexico D.F. (Mexico); Francois L, J.L. [UNAM, 04500 Mexico D.F. (Mexico)]. e-mail: lpg@nuclear.inin.mx

    2006-07-01

    The Cf-252 is a fast neutrons emitting radioisotope by spontaneous fission that can be used as sealed source in medicine applications, industry and research. Commercially its offer sources of different sizes, compact and with a fast neutrons emission of the order of 10{sup 6} n/s-{mu}g and an energy spectra that presents respectively maxim and average energy in 2.1 MeV and 0.7 MeV. In medicine new applications are being developed for the treatment of patient with hypoxic and voluminous tumors, where the therapy with photons has not given positive results, as well as for the protocols of therapy treatment by boron neutron capture, where very small sources of Cf-252 will be used with the interstitial brachytherapy technique of high and low dose rate. In this work an analysis of how the small differences that exist in the elementary composition of 4 wicked tumors, 4 ICRU healthy tissues and 3 substitute materials of ICRU tissue used in dosimetry are presented, its generate changes in the neutrons kerma coefficient in function of the energy and consequently in the absorbed dose in the interval of 11 eV to 29 MeV. These differences can produce maximum variations of the neutron kerma coefficients ratio for E{sub n} > 1 keV of the one: 15% tumor/ICRU guest healthy tissue, 12% ICRU tumor/muscle, 12% ICRU healthy tissues ICRU/ICRU muscle, 22% substitutes tissue/tumor and 22% ICRU substitutes tissue/muscle. Also, it was found that the average value of the neutrons kerma coefficient for the 4 wicked tumors is from 6% to 7% smaller that the average value for the soft tissue in the interval energy of interest for therapy with fast neutrons with E{sub n} > 1 MeV. These results have a special importance during the planning process of brachytherapy treatments with sources of {sup 252}Cf, to optimize and to individualize the patients treatments. (Author)

  12. The Fricke dosimeter as an absorbed dose to water primary standard for Ir-192 brachytherapy

    International Nuclear Information System (INIS)

    The aim of this project was to develop an absorbed dose to water primary standard for Ir-192 brachytherapy based on the Fricke dosimeter. To achieve this within the framework of the existing TG-43 protocol, a determination of the absorbed dose to water at the reference position, D(r0,θ0), was undertaken. Prior to this investigation, the radiation chemical yield of the ferric ions (G-value) at the Ir-192 equivalent photon energy (0.380 MeV) was established by interpolating between G-values obtained for Co-60 and 250 kV x-rays.An irradiation geometry was developed with a cylindrical holder to contain the Fricke solution and allow irradiations in a water phantom to be conducted using a standard Nucletron microSelectron V2 HDR Ir-192 afterloader. Once the geometry and holder were optimized, the dose obtained with the Fricke system was compared to the standard method used in North America, based on air-kerma strength.Initial investigations focused on reproducible positioning of the ring-shaped holder for the Fricke solution with respect to the Ir-192 source and obtaining an acceptable type A uncertainty in the optical density measurements required to yield the absorbed dose. Source positioning was found to be reproducible to better than 0.3 mm, and a careful cleaning and control procedure reduced the variation in optical density reading due to contamination of the Fricke solution by the PMMA holder. It was found that fewer than 10 irradiations were required to yield a type A standard uncertainty of less than 0.5%.Correction factors to take account of the non-water components of the geometry and the volume averaging effect of the Fricke solution volume were obtained from Monte Carlo calculations. A sensitivity analysis showed that the dependence on the input data used (e.g. interaction cross-sections) was small with a type B uncertainty for these corrections estimated to be 0.2%.The combined standard uncertainty in the determination of absorbed dose to water at

  13. The effects of energy paths and emission controls and standards on future trends in China's emissions of primary air pollutants

    Science.gov (United States)

    Zhao, Y.; Zhang, J.; Nielsen, C. P.

    2014-09-01

    To examine the efficacy of China's actions to control atmospheric pollution, three levels of growth of energy consumption and three levels of implementation of emission controls are estimated, generating a total of nine combined activity-emission control scenarios that are then used to estimate trends of national emissions of primary air pollutants through 2030. The emission control strategies are expected to have more effects than the energy paths on the future emission trends for all the concerned pollutants. As recently promulgated national action plans of air pollution prevention and control (NAPAPPC) are implemented, China's anthropogenic pollutant emissions should decline. For example, the emissions of SO2, NOx, total suspended particles (TSP), PM10, and PM2.5 are estimated to decline 7, 20, 41, 34, and 31% from 2010 to 2030, respectively, in the "best guess" scenario that includes national commitment of energy saving policy and implementation of NAPAPPC. Should the issued/proposed emission standards be fully achieved, a less likely scenario, annual emissions would be further reduced, ranging from 17 (for primary PM2.5) to 29% (for NOx) declines in 2015, and the analogue numbers would be 12 and 24% in 2030. The uncertainties of emission projections result mainly from the uncertain operational conditions of swiftly proliferating air pollutant control devices and lack of detailed information about emission control plans by region. The predicted emission trends by sector and chemical species raise concerns about current pollution control strategies: the potential for emissions abatement in key sectors may be declining due to the near saturation of emission control devices use; risks of ecosystem acidification could rise because emissions of alkaline base cations may be declining faster than those of SO2; and radiative forcing could rise because emissions of positive-forcing carbonaceous aerosols may decline more slowly than those of SO2 emissions and thereby

  14. Recoil proton, alpha particle, and heavy ion impacts on microdosimetry and RBE of fast neutrons: analysis of kerma spectra calculated by Monte Carlo simulation

    Energy Technology Data Exchange (ETDEWEB)

    Pignol, J.-P. [Toronto-Sunnybrook Regional Cancer Centre, Radiotherapy Dept., Toronto, Ontario (Canada); Slabbert, J. [National Accelerator Centre, Faure (South Africa)

    2001-02-01

    Fast neutrons (FN) have a higher radio-biological effectiveness (RBE) compared with photons, however the mechanism of this increase remains a controversial issue. RBE variations are seen among various FN facilities and at the same facility when different tissue depths or thicknesses of hardening filters are used. These variations lead to uncertainties in dose reporting as well as in the comparisons of clinical results. Besides radiobiology and microdosimetry, another powerful method for the characterization of FN beams is the calculation of total proton and heavy ion kerma spectra. FLUKA and MCNP Monte Carlo code were used to simulate these kerma spectra following a set of microdosimetry measurements performed at the National Accelerator Centre. The calculated spectra confirmed major classical statements: RBE increase is linked to both slow energy protons and alpha particles yielded by (n,{alpha}) reactions on carbon and oxygen nuclei. The slow energy protons are produced by neutrons having an energy between 10 keV and 10 MeV, while the alpha particles are produced by neutrons having an energy between 10 keV and 15 MeV. Looking at the heavy ion kerma from <15 MeV and the proton kerma from neutrons <10 MeV, it is possible to anticipate y* and RBE trends. (author)

  15. The Recent Development of the Test Standards for Ventilation air filters and Cabin Air Filters%通风和座舱空气过滤器试验标准的最新进展

    Institute of Scientific and Technical Information of China (English)

    丰兰

    2011-01-01

    The test standards and methods for two different air filters of ventilation air filters and cabin air filters were introduced,especially the difference of the test standards and methods between the ventilation air filters and cabin air filters.And the international present situation and the problem existed internal were also pointed,finally the development of cabin air filters were analyzed.%主要介绍了通风用空气过滤器和座舱式空气过滤器两个不同类型的空气过滤器的试验方法和标准,重点介绍了各试验方法和标准的区别,阐述分析了目前国际的现状和国内普遍存在的问题,最后介绍了目前座舱式空气过滤器的发展,为进一步研究提供参考。

  16. First international comparison of primary absorbed dose to water standards in the medium-energy X-ray range

    Science.gov (United States)

    Büermann, Ludwig; Guerra, Antonio Stefano; Pimpinella, Maria; Pinto, Massimo; de Pooter, Jacco; de Prez, Leon; Jansen, Bartel; Denoziere, Marc; Rapp, Benjamin

    2016-01-01

    This report presents the results of the first international comparison of primary measurement standards of absorbed dose to water for the medium-energy X-ray range. Three of the participants (VSL, PTB, LNE-LNHB) used their existing water calorimeter based standards and one participant (ENEA) recently developed a new standard based on a water-graphite calorimeter. The participants calibrated three transfer chambers of the same type in terms of absorbed dose to water (NDw) and in addition in terms of air kerma (NK) using the CCRI radiation qualities in the range 100 kV to 250 kV. The additional NK values were intended to be used for a physical analysis of the ratios NDw/NK. All participants had previously participated in the BIPM.RI(I)-K3 key comparison of air kerma standards. Ratios of pairs of NMI's NK results of the current comparison were found to be consistent with the corresponding key comparison results within the expanded uncertainties of 0.6 % - 1 %. The NDw results were analysed in terms of the degrees of equivalence with the comparison reference values which were calculated for each beam quality as the weighted means of all results. The participant's results were consistent with the reference value within the expanded uncertainties. However, these expanded uncertainties varied significantly and ranged between about 1-1.8 % for the water calorimeter based standards and were estimated at 3.7 % for the water-graphite calorimeter. It was shown previously that the ratios NDw/NK for the type of ionization chamber used as transfer chamber in this comparison were very close (within less than 1 %) to the calculated values of (bar muen/ρ)w,ad, the mean values of the water-to-air ratio of the mass-energy-absorption coefficients at the depth d in water. Some of the participant's results deviated significantly from the expected behavior. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of

  17. 76 FR 45011 - Control of Air Pollution From Aircraft and Aircraft Engines; Proposed Emission Standards and Test...

    Science.gov (United States)

    2011-07-27

    ... from Aircraft and Aircraft Engines; Emission Standards and Test Procedures;'' Final Rule, 62 FR 25356... From Aircraft and Aircraft Engines; Proposed Emission Standards and Test Procedures; Proposed Rule #0... and Aircraft Engines; Proposed Emission Standards and Test Procedures AGENCY: Environmental...

  18. Estándares para el Sistema de Bibliotecas de la Universidad de Buenos Aires Standards for the Universidad de Buenos Aires Libraries System

    OpenAIRE

    Elsa Elena Elizalde

    2009-01-01

    La Coordinación General del Sistema de Bibliotecas y de Información -SISBI- de la Universidad de Buenos Aires propuso la conformación de un Grupo de Trabajo para el estudio y la definición de los requerimientos para un adecuado nivel de prestación de los servicios de todas sus bibliotecas. Estos estándares externos completarán y actualizarán los «Lineamientos para una Política Bibliotecaria de la Universidad de Buenos Aires (Resolución CS Nº 222/94)». El objetivo del conjunto de criterios que...

  19. Indoor Air Quality In Maine Schools: Report of the Task Force To Examine the Establishment and Implementation of State Standards for Indoor Air Quality in Maine Schools.

    Science.gov (United States)

    Malcolm, Judith

    Asserting that in Maine and across the nation, school buildings are becoming increasingly plagued with indoor air quality (IAQ) problems which contribute to a variety of illnesses in children and adults, this report from a Maine state legislative task force identifies appropriate policies and identifies actions necessary for the prevention and…

  20. 75 FR 10252 - Release of Draft Documents Related to the Review of the National Ambient Air Quality Standards...

    Science.gov (United States)

    2010-03-05

    ... Exposure Assessment to Support the Review of the Carbon Monoxide Primary National Ambient Air Quality... draft assessment document: Policy Assessment for the Review of the Carbon Monoxide National Ambient Air... Risk and Exposure Assessment to Support the Review of the Carbon Monoxide Primary National Ambient......

  1. Quality control methodology and implementation of X-radiation standards beams, mammography level, following the standard IEC 61267

    Energy Technology Data Exchange (ETDEWEB)

    Correa, E.L.; Vivolo, V. [Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN), Avenida Professor Lineu Prestes 2242, Cidade Universitaria, Sao Paulo, SP (Brazil); Potiens, M.P.A., E-mail: mppalbu@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN), Avenida Professor Lineu Prestes 2242, Cidade Universitaria, Sao Paulo, SP (Brazil)

    2012-07-15

    This study presents the results of the establishment of a quality control program developed and applied for the X-ray system of the Calibration Laboratory of IPEN. The X-ray standard beams, mammography level, using molybdenum and aluminum as additional filtration were established after the application of this quality control and the spectrometry of these qualities was made. The reference ionization chamber has traceability to the PTB. The radiation qualities RQR-M, RQA-M, RQN-M and RQB-M, following the recommendations of the IEC 61267 and the IAEA TRS 457 were established. - Highlights: Black-Right-Pointing-Pointer Determination of the additional filtration for each mammography radiation quality. Black-Right-Pointing-Pointer Determination of the KQ values for the WAV and WMV radiation qualities. Black-Right-Pointing-Pointer Determination of the air-kerma rates for all radiation qualities. Black-Right-Pointing-Pointer The uncertainties have been calculated using the type A and type B uncertainties. Black-Right-Pointing-Pointer Establishment of the qualities that use a PMMA phantom (WAN, WAB, WMN and WMB).

  2. 77 FR 36341 - Control of Air Pollution From Aircraft and Aircraft Engines; Emission Standards and Test Procedures

    Science.gov (United States)

    2012-06-18

    ... and Aircraft Engines; Emission Standards and Test Procedures;'' Final Rule, 70 FR 2521, November 17... From Aircraft and Aircraft Engines; Emission Standards and Test Procedures; Final Rule #0;#0;Federal...: Final rule. SUMMARY: EPA is adopting several new aircraft engine emission standards for oxides...

  3. Calculation and evaluation of cross-sections and kerma factors for neutrons up to 100 MeV on {sup 16}O and {sup 14}N

    Energy Technology Data Exchange (ETDEWEB)

    Chadwick, M.B. [California Univ., Livermor, CA (United States). Lawrence Livermore National Lab.; Young, P.G.

    1997-03-01

    We present evaluations of the interaction of neutrons with energies between 20 and 100 MeV with oxygen and nitrogen nuclei, which follows on from our previous work on carbon. Our aim is to accurately represent integrated cross sections, inclusive emission spectra, and kerma factors, in a data library which can be used in radiation transport calculations. We apply the FKK-GNASH nuclear model code, which includes Hauser-Feshbach, preequilibrium, and direct reaction mechanisms, and use experimental measurements to optimize the calculations. We determine total, elastic, and nonelastic cross sections, angle-energy correlated emission spectra for light ejectiles with A {<=} 4 and gamma-rays, and average energy depositions. Our results for charged-particle emission spectra agree well with the measurements of Subramanian et al. We compare kerma factors derived from our evaluated cross sections with experimental data, providing an integral benchmarking of our work. (author). 52 refs.

  4. Comparison between predicted duct effectiveness from proposed ASHRAE Standard 152P and measured field data for residential forced air cooling systems

    Energy Technology Data Exchange (ETDEWEB)

    Siegel, Jeffrey A.; McWilliams, Jennifer A.; Walker, Iain S.

    2002-04-01

    The proposed ASHRAE Standard 152P ''Method of Test for Determining the Design and Seasonal Efficiencies of Residential Thermal Distribution Systems'' (ASHRAE 2002) has recently completed its second public review. As part of the standard development process, this study compares the forced air distribution system ratings provided by the public review draft of Standard 152P to measured field results. 58 field tests were performed on cooling systems in 11 homes in the summers of 1998 and 1999. Seven of these houses had standard attics with insulation on the attic floor and a well-vented attic space. The other four houses had unvented attics where the insulation is placed directly under the roof deck and the attic space is not deliberately vented. Each house was tested under a range of summer weather conditions at each particular site, and in some cases the amount of duct leakage was intentionally varied. The comparison between 152P predicted efficiencies and the measured results includes evaluation of the effects of weather, duct location, thermal conditions, duct leakage, and system capacity. The results showed that the difference between measured delivery effectiveness and that calculated using proposed Standard 152P is about 5 percentage points if weather data, duct leakage and air handler flow are well known. However, the accuracy of the standard is strongly dependent on having good measurements of duct leakage and system airflow. Given that the uncertainty in the measured delivery effectiveness is typically also about 5 percentage points, the Standard 152P results are acceptably close to the measured data.

  5. Flight Standards Automation System

    Data.gov (United States)

    Department of Transportation — FAVSIS supports Flight Standards Service (AFS) by maintaining their information on entities such as air carriers, air agencies, designated airmen, and check airmen....

  6. Survey of image quality and patient dose in simple radiographic examinations: Establishing guidance levels and comparison with international standards

    International Nuclear Information System (INIS)

    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)

  7. 2007 Critical Review Discussion -- Will the circle be unbroken: a history of the U.S. national ambient air quality standards

    Energy Technology Data Exchange (ETDEWEB)

    Judith C. Chow; John G. Watson; Howard J. Feldman (and others) [Desert Research Institute, Reno, NV (United States)

    2007-10-15

    In the review, John D. Bachmann traces the regulatory history of U.S. air pollution from the beginning of the 20th century to the present. The review divides this progress into four segments: (1) 1900-1970, from smoke abatement to federal involvement and the establishment of air quality management (AQM) in the 1970 Clean Air Act (CAA); (2) 1971-1976, when the first National Ambient Air Quality Standards (NAAQS) were promulgated and implemented; (3) 1977-1993, which included the first NAAQS revisions, major CAA amendments, and the evolution of AQM; and (4) 1993-2006, the second and third waves of NAAQS revisions and their implementation in the context of the 1990 CAA amendments. A discussant's commentary does not necessarily reflect the position of his or her respective organization. This Critical Review Discussion was compiled from written submissions and presentation transcripts. The invited discussants are as follows: Mr. Howard J. Feldman, director of regulatory and scientific affairs for the American Petroleum Institute; Ms. Janice E. Nolen, assistant vice president of national policy and advocacy for the American Lung Association; Dr. Barry Wallerstein, executive officer at the South Coast Air Quality Management District; Dr. John G. Watson, research professor in the Division of Atmospheric Sciences at the Desert Research Institute; Dr. George M. Hidy of Envair/Aerochem; Dr. Paul J. Lioy, Department of Environmental and Occupational Medicine; Robert Wood Johnson Medical School, University of Medicine and Dentistry, New Jersey; Dr. Herbert McKee, environmental consultant; Mr. David Mobley of the Atmospheric Modeling Division of the EPA's Office of Research and Development; and Mr. Keith Baugues, P.E., of air services for KERAMIDA Environmental. 127 refs.

  8. What is the explanation for the changes to cobalt-60 tissue - air ratios in BJR Supplement 25?

    International Nuclear Information System (INIS)

    Values of tissue - air ratio (TAR) in the recent British Journal of radiology (BJR) Supplement 25 have been increased by nearly 2% over the values which have been accepted for the past 30 years. The need for this was shown by analysis of previous data using scaling laws, together with Monte Carlo calculations and careful re-measurement. However, it was not clear why previous determinations of TAR were in error: it was not, as some workers argued, because scattered radiation had been included in the absorbed dose in the miniphantom, because TAR data in BJR Supplement 17 had been derived from peak scatter factor (PSF), which is not based on the miniphantom concept. The purpose of this paper is to find the real explanation of why the PSF and, therefore, TAR were underestimated for so long. Two definitions of PSF are considered: one based on kerma and one based on dose. This paper relates PSF of either definition to measurements of air kerma by including in the derivation the scatter in the plug which replaces the chamber when it has been removed from the surface of the water phantom. The kerma-based PSF is found to be 2% higher than the simple ratio of chamber readings in phantom and in air. The value of the dose-based definition agrees with that of the Kerma-based definition to within 0.2%. It is the scatter in the replacement plug in the surface of the water phantom which was effectively ignored by previous workers, and which explains the underestimates of around 2% in PSF nd TAR. The value of the dose-based PSF differs slightly from that of the Kerma-based PSF because of the different distributions of primary and scatter photon fluence. (author)

  9. Calculation of the backscattering in water and compared to the values in air; Calculo del factor de retrodispersion en agua y comparativa con los valores en aire

    Energy Technology Data Exchange (ETDEWEB)

    Minano Herrero, J. A.; Sarasa Rubio, A.; Roldan Arjona, J. M.

    2011-07-01

    The purpose of this paper is to calculate values of BSF in water and comparison with data on air 11SF found in the literature. For this simulations have been performed by the Monte Carlo method for calculating values ??kerma water in the presence of a manikin of this material and in the absence thereof. The simulations were performed for monoenergetic beams in order to facilitate the calculation of the BSF for any spectral distribution of those found in the field of radiology.

  10. Technical Requirements and Principles for the Standards Development of the Key Parts for Rotor Air-conditioning Compressors

    Institute of Scientific and Technical Information of China (English)

    Sun Min; Wen Yun; Fan Zhangzeng

    2011-01-01

    ntroductionSince 2000,air-conditioning sales continues to grow,and the development of air-conditioning market makes a booming market of compressor.At the present time,compressor production rising all the way,and the sales steps up the new steps constantly.Tendency chart is shown in figure 1.Rotor compressor with its simple structure,small volume,light weight,easy processed mechanical parts,reliable operation and other excellent characteristics occupied the dominant position in the market.Compared with reciprocating compressor on the same application situation,decreased in the size by 40%~50%,weight was reduced by 40%~50%.But there were also disadvantages,mainly large friction loss,friction power consumption was about 10%of compressor's total power input.

  11. The effects of energy paths and emission controls and standards on future trends in China's emissions of primary air pollutants

    OpenAIRE

    Zhao, Y.; Zhang, J.; C. P. Nielsen

    2014-01-01

    To examine the efficacy of China's actions to control atmospheric pollution, three levels of growth of energy consumption and three levels of implementation of emission controls are estimated, generating a total of nine combined activity-emission control scenarios that are then used to estimate trends of national emissions of primary air pollutants through 2030. The emission control strategies are expected to have more effects than the energy paths on the future emission tre...

  12. The effects of energy paths and emission controls and standards on future trends in China's emissions of primary air pollutants

    OpenAIRE

    Zhao, Y.; Zhang, J.; C. P. Nielsen

    2014-01-01

    To examine the efficacy of China's actions to control atmospheric pollution, three levels of growth of energy consumption and three levels of implementation of emission controls are estimated, generating a total of nine combined activity-emission control scenarios that are then used to estimate trends of national emissions of primary air pollutants through 2030. The emission control strategies are expected to have more effects than the energy paths on the fu...

  13. 77 FR 64036 - Determination of Attainment of the 1-Hour Ozone National Ambient Air Quality Standards in the...

    Science.gov (United States)

    2012-10-18

    ... the California Air Resources Board (CARB) Web site show a single exceedance (0.128 ppm) of the 1-hour...-0014)......... 0.0 0.0 0.0 0.0 0.0 0.0 Sloughhouse Rd. (06-067-5003) 3.0 0.0 0.0 0.0 1.0 0.0 Vacaville... Action On......

  14. Feasibility and difficulties on China new air quality standard compliance: PRD case of PM2.5 and ozone from 2010 to 2025

    Directory of Open Access Journals (Sweden)

    H. Liu

    2013-08-01

    Full Text Available Improving the air quality in China is a long and arduous task. Although China has made very aggressive plan on pollutants control, the difficulties to achieve the new air quality goals are still significant. In north, PM2.5 and PM10 are still far beyond the standards. In south, O3 goal is much challenged. A lot of cities are making their city implementation plan (CIP for new air quality goals. In this study, a southern city, Guangzhou, is selected to analyze the feasibility and difficulties on new air quality standard compliance, as well as the CIP evaluation. A comprehensive study of air quality status in Guangzhou and surrounding area is conducted based on 22 sites monitoring data of O3, PM2.5 and PM10. The monthly non-attainment rates for O3 vary in 7–25% from May to November. The city average PM2.5 concentration is 41 μg m–3 in Guangzhou in 2010, which needs to be reduced by at least 15% to achieve the target of 35 μg m–3. The PM2.5 high violate months are from November to March. Guangzhou CIP was then evaluated with PM2.5 and O3 placed in a core position. The emission amount of NOx, PM10, PM2.5 and VOC in 2025 would be controlled to 600, 420, 200 and 860 thousand tons respectively. Analysis of air quality using the MM5-STEM model suggests that the long-term control measures would achieve the PM2.5 and PM10 goals successfully by 2025. The PM2.5 annual average concentration would be reduced to 20.8 μg m–3 in 2025. The O3 non-attainment rate would increase from 7.1% in 2010 to 12.9% in 2025 and become the most primary atmospheric environmental problem. Guangzhou needs very strong control on VOCs to reduce its ozone. The VOC / NOx reduction ratio should reach at least 2 : 1 (in California, it is about 3 : 1, instead of the current plan of 0.7 : 1. The evaporative emissions control from vehicle non-tailpipe emission and solvent usage should be enhanced and regional ozone transport must be taken into account.

  15. Interlaboratory evaluation of a standardized inductively coupled plasma mass spectrometry method for the determination of trace beryllium in air filter samples.

    Science.gov (United States)

    Ashley, Kevin; Brisson, Michael J; Howe, Alan M; Bartley, David L

    2009-12-01

    A collaborative interlaboratory evaluation of a newly standardized inductively coupled plasma mass spectrometry (ICP-MS) method for determining trace beryllium in workplace air samples was carried out toward fulfillment of method validation requirements for ASTM International voluntary consensus standard test methods. The interlaboratory study (ILS) was performed in accordance with an applicable ASTM International standard practice, ASTM E691, which describes statistical procedures for investigating interlaboratory precision. Uncertainty was also estimated in accordance with ASTM D7440, which applies the International Organization for Standardization Guide to the Expression of Uncertainty in Measurement to air quality measurements. Performance evaluation materials (PEMs) used consisted of 37 mm diameter mixed cellulose ester filters that were spiked with beryllium at levels of 0.025 (low loading), 0.5 (medium loading), and 10 (high loading) microg Be/filter; these spiked filters were prepared by a contract laboratory. Participating laboratories were recruited from a pool of over 50 invitees; ultimately, 20 laboratories from Europe, North America, and Asia submitted ILS results. Triplicates of each PEM (blanks plus the three different loading levels) were conveyed to each volunteer laboratory, along with a copy of the draft standard test method that each participant was asked to follow; spiking levels were unknown to the participants. The laboratories were requested to prepare the PEMs by one of three sample preparation procedures (hotplate or microwave digestion or hotblock extraction) that were described in the draft standard. Participants were then asked to analyze aliquots of the prepared samples by ICP-MS and to report their data in units of mu g Be/filter sample. Interlaboratory precision estimates from participating laboratories, computed in accordance with ASTM E691, were 0.165, 0.108, and 0.151 (relative standard deviation) for the PEMs spiked at 0.025, 0

  16. The effect of the Standard Nomenclature for Air Pollution (SNAP) categories on ozone and PM2.5 concentrations over Europe

    Science.gov (United States)

    Tagaris, Efthimios; Sotiropoulou, Rafaella-Eleni P.; Gounaris, Nikos; Andronopoulos, Spyros; Vlachogiannis, Diamando

    2015-04-01

    The objective of this study is to estimate the contribution of different anthropogenic emission sources on ozone and PM2.5 concentrations over Europe since anthropogenic activities (and the related emissions) are the reason of air quality degradation. Gridded yearly averaged anthropogenic emissions for the year 2006 over Europe are provided by TNO at a 0.1×0.1 degree resolution. Emission sources have been classified into different activities according to the Standard Nomenclature for Air Pollution (SNAP). The available data include annual total emissions of CH4, CO, NH3, NMVOC, NOx, PM10, PM2.5, and SO2 for both area and point sources in ten (10) SNAP categories: power generation, residential-commercial and other combustion, industrial combustion, industrial processes, extraction distribution of fossil fuels, solvent use, road transport, other mobile sources, waste treatment and disposal, agriculture. Mobile sources and road transport are the major sources of NOx emissions followed by power generation units. Power generation is also the major source for SO2 emissions followed by mobile sources. Agricultural activities dominate NH3 emissions while combustion sources followed by mobile sources and road transport are the main sources for primary PM2.5. Emissions are processed by the Sparse Matrix Operator Kernel Emissions (SMOKE) v2.6 modeling system to convert their resolution to the resolution needed by the air quality model The Community Multiscale Air Quality (CMAQ) v4.7 Modeling System with the Carbon Bond mechanism (CB05) is used for the regional air quality modeling over Europe at 35km grid spacing. Results quantify the contribution of each SNAP category on ozone and PM2.5 concentrations, locally, across Europe.

  17. International symposium on standards and codes of practice in medical radiation dosimetry. Book of extended synopses

    International Nuclear Information System (INIS)

    The development of radiation measurement standards by National Metrology Institutes (NMIs) and their dissemination to Secondary Standard Dosimetry Laboratories (SSDLs), cancer therapy centres and hospitals represent essential aspects of the radiation dosimetry measurement chain. Although the demands for accuracy in radiotherapy initiated the establishment of such measurement chains, similar traceable dosimetry procedures have been implemented, or are being developed, in other areas of radiation medicine (e.g. diagnostic radiology and nuclear medicine), in radiation protection and in industrial applications of radiation. In the past few years the development of primary standards of absorbed dose to water in 60Co for radiotherapy dosimetry has made direct calibrations in terms of absorbed dose to water available in many countries for the first time. Some laboratories have extended the development of these standards to high energy photon and electron beams and to low and medium energy x-ray beams. Other countries, however, still base their dosimetry for radiotherapy on air kerma standards. Dosimetry for conventional external beam radiotherapy was probably the field where standardized procedures adopted by medical physicists at hospitals were developed first. Those were related to exposure and air kerma standards. The recent development of Codes of Practice (or protocols) based on the concept of absorbed dose to water has led to changes in calibration procedures at hospitals. The International Code of Practice for Dosimetry Based on Standards of Absorbed Dose to Water (TRS 398) was sponsored by the International Atomic Energy Agency (IAEA), World Health Organization (WHO), Pan-American Health Organization (PAHO) and the European Society for Therapeutic Radiology and Oncology (ESTRO) and is expected to be adopted in many countries worldwide. It provides recommendations for the dosimetry of all types of beams (except neutrons) used in external radiotherapy and satisfies

  18. Tank exhaust comparison with 40 CFR 61.93, Subpart H, and other referenced guidelines for Tank Farms National Emission Standards for Hazardous Air Pollutant (NESHAP) designated stacks

    International Nuclear Information System (INIS)

    The US Environmental Protection Agency (EPA) promulgated National Emission Standards other than Radon from US Department of Energy (DOE) Facilities (40 CFR 61, Subpart H) on December 15, 1989. The regulations specify procedures, equipment, and test methods that.are to be used to measure radionuclide emissions from exhaust stacks that are designated as National Emission Standards for Hazardous Air Pollutant (NESHAP) stacks. Designated NESHAP stacks are those that have the potential to cause any member of the public to receive an effective dose equivalent (EDE) greater than or equal to 0.1 mrem/year, assuming all emission controls were removed. Tank Farms currently has 33 exhaust stacks, 15 of which are designated NESHAP stacks. This document assesses the compliance status of the monitoring and sampling systems for the designated NESHAP stacks

  19. Tank exhaust comparison with 40 CFR 61.93, Subpart H, and other referenced guidelines for Tank Farms National Emission Standards for Hazardous Air Pollutant (NESHAP) designated stacks

    Energy Technology Data Exchange (ETDEWEB)

    Bachand, D.D.; Crummel, G.M.

    1994-07-01

    The US Environmental Protection Agency (EPA) promulgated National Emission Standards other than Radon from US Department of Energy (DOE) Facilities (40 CFR 61, Subpart H) on December 15, 1989. The regulations specify procedures, equipment, and test methods that.are to be used to measure radionuclide emissions from exhaust stacks that are designated as National Emission Standards for Hazardous Air Pollutant (NESHAP) stacks. Designated NESHAP stacks are those that have the potential to cause any member of the public to receive an effective dose equivalent (EDE) greater than or equal to 0.1 mrem/year, assuming all emission controls were removed. Tank Farms currently has 33 exhaust stacks, 15 of which are designated NESHAP stacks. This document assesses the compliance status of the monitoring and sampling systems for the designated NESHAP stacks.

  20. 77 FR 29750 - Fifteenth Meeting: RTCA Special Committee 214, Joint With EUROCAE WG-78, Standards for Air...

    Science.gov (United States)

    2012-05-18

    ... schedule Status of Standards Revision A of DO305/ED154 DO-281B/ED-92B Review SC214/WG78 schedule, impact on... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF TRANSPORTATION... visiting the Maastricht centre, hotels and how to get here can be found at...

  1. 77 FR 9303 - National Emission Standards for Hazardous Air Pollutants From Coal- and Oil-Fired Electric...

    Science.gov (United States)

    2012-02-16

    ... standards for stationary combustion turbines (CT) on March 5, 2004 (40 CFR part 63 subpart YYYY; 69 FR 10512... petroleum coke synthesis gas/syngas), we do not consider these CTs to be EGUs for purposes of this final... generating units (76 FR 24976). After consideration of public comments, the EPA is finalizing these rules...

  2. Biomonitoring of trace-element air pollution in a gold mining area in Ghana using the generalized k0-standardization NAA method

    International Nuclear Information System (INIS)

    Full text: Mining activities contribute immensely to trace element atmospheric pollution. In Ghana, air pollution due to gold mining is the least investigated. In order to obtain preliminary information on air quality in the mining areas, the generalized ko- Standardization neutron activation analysis (NAA) method for nuclides following '1/v' and non-'1/v' (n,γ) reactions was used to analyse lichen samples from Prestea, a gold mining area in Ghana. Using the computed EPI values of both the Hogdahl-convention and the modified Westcott-formalism with gold as comparator standard, the IAEA lichen 336 certified reference material (CRM) and the lichen samples were irradiated in the inner irradiation site of the Ghana Research Reactor-1 (GHARR-1) operating at a thermal neutron flux of 5.0x1011ns-1cm-2. Comparison of the results with samples obtained from a non-mining (control) area, indicates that values of some metal pollutants such as As, Cr, Sb, and V were found to be higher in the lichens from the mining area than those in the non-mining area (control area); signifying accumulation of these metal pollutant due to gold - mining activities. (author)

  3. Overview of ozone human exposure and health risk analyses used in the U.S. EPA's review of the ozone air quality standard.

    Energy Technology Data Exchange (ETDEWEB)

    Whitfield, R. G.

    1999-03-04

    This paper presents an overview of the ozone human exposure and health risk analyses developed under sponsorship of the U.S. Environmental Protection Agency (EPA). These analyses are being used in the current review of the national ambient air quality standards (NAAQS) for ozone. The analyses consist of three principal steps: (1) estimating short-term ozone exposure for particular populations (exposure model); (2) estimating population response to exposures or concentrations (exposure-response or concentration-response models); and (3) integrating concentrations or exposure with concentration-response or exposure-response models to produce overall risk estimates (risk model). The exposure model, called the probabilistic NAAQS exposure model for ozone (pNEM/03), incorporates the following factors: hourly ambient ozone concentrations; spatial distribution of concentrations; ventilation state of individuals at time of exposure; and movement of people through various microenvironments (e.g., outdoors, indoors, inside a vehicle) of varying air quality. Exposure estimates are represented by probability distributions. Exposure-response relationships have been developed for several respiratory symptom and lung function health effects, based on the results of controlled human exposure studies. These relationships also are probabilistic and reflect uncertainties associated with sample size and variability of response among subjects. The analyses also provide estimates of excess hospital admissions in the New York City area based on results from an epidemiology study. Overall risk results for selected health endpoints and recently analyzed air quality scenarios associated with alternative 8-hour NAAQS and the current 1-hour standard for outdoor children are used to illustrate application of the methodology.

  4. Development of standardized air-blown coal gasifier/gas turbine concepts for future electric power systems

    Energy Technology Data Exchange (ETDEWEB)

    Sadowski, R.S.; Brown, M.J.; Harriz, J.T.; Ostrowski, E.

    1991-01-01

    The cost estimate provided for the DOE sponsored study of Air Blown Coal Gasification was developed from vendor quotes obtained directly for the equipment needed in the 50 MW, 100 MW, and 200 MW sized plants and from quotes from other jobs that have been referenced to apply to the particular cycle. Quotes were generally obtained for the 100 MW cycle and a scale up/down factor was used to generate the cost estimates for the 200 MW and 50 MW cycles, respectively. Information from GTPro (property of Thermoflow, Inc.) was used to estimate the cost of the 200 MW and 50 MW gas turbine, HRSG, and steam turbines. To available the use of GTPro's estimated values for this equipment, a comparison was made between the quotes obtained for the 100 MW cycle (ABB GT 11N combustion turbine and a HSRG) against the estimated values by GTPro.

  5. Quality management system of secondary standards dosimetry laboratory in Sri Lanka

    International Nuclear Information System (INIS)

    ). This network provides assistance for members to maintain consistency of Radiation Standard measurements in their dosimetry laboratories. Reference electrometer with ion-chambers has been calibrated from IAEA Radiation Standard Laboratory at Seibersdorf in Austria which is traceable to primary standards at BIPM. Measuring standards are calibrated using these reference standards. The SSDL also participates IAEA TLD dose audit program to ensure the accuracy of radiation standards and is firmly committed to achieve global harmonization wherever possible. Hence the QMS assures the quality and accuracy of the services provided to institutions such as hospitals, research institutes, industries for the safety of their radiation workers. Reference electrometer with ion-chambers is used to standardize the gamma radiation fields. Measurements are made from 1 m onwards from the source with 25 cm step increment along the beam axis. Ten consecutive readings are taken for the measurement of air-kerma rate at a point. Ambient temperature, pressure and humidity at the beginning and end of measurements of each measurement are taken by using calibrated ancillary instruments, which are traceable to national and international standards, for correction of density of air mass in the ion-chamber. This air-kerma rate is converted to ambient dose equivalent rate (ADER) for the calibration of area monitors and personal dose equivalent rate (PDER) for calibration of personal monitoring instruments/devices as recommended in IAEA Safety Report Series 16. Graphs, Distance Vs dose rate for ADER and PDER using power fitting formula are established. Decay correction is applied for each data point measured and a fresh graph, Distance Vs dose rate is prepared each day prior to calibration of instruments. Verification of dose given by the software program is done with manual calculation of three data points. Energies of X-ray beams used for protection level calibration are verified with first and second

  6. Evaluation of cross sections and calculation of kerma factors for neutrons up to 80 MeV on {sup 12}C

    Energy Technology Data Exchange (ETDEWEB)

    Harada, M.; Watanabe, Y. [Kyushu Univ., Fukuoka (Japan); Chiba, S.; Fukahori, T.

    1997-03-01

    We have evaluated the cross sections for neutrons with incident energies from 20 to 80 MeV on {sup 12}C for the JENDL high-energy file. The total cross sections were determined by a generalized least-squares method with available experimental data. The cross sections of elastic and inelastic scattering to the first 2{sup +} were evaluated with the theoretical calculations. The optical potentials necessary for these calculations were derived using a microscopic approach by Jeukenne-Lejeune-Mahaux. For the evaluation of double differential emission cross sections (DDXs), we have developed a code system SCINFUL/DDX in which total 35 reactions including the 3-body simultaneous breakup process (n+{sup 12}C {yields} n+{alpha}+{sup 8}Be) can be taken into consideration in terms of a Monte Carlo method, and have calculated the DDXs of all light-emissions (A{<=}4) and heavier reaction products. The results for protons, deuterons, and alphas showed overall good agreement with experimental data. The code is also applicable for calculations of total and partial kerma factors. Total kerma factors calculated for energies from 20 to 80 MeV were compared with the measurements and the other latest evaluations from the viewpoints of medical application and nuclear heating estimation. (author)

  7. Human occupations and environmental changes in the Nile valley during the Holocene: The case of Kerma in Upper Nubia (northern Sudan)

    Science.gov (United States)

    Honegger, Matthieu; Williams, Martin

    2015-12-01

    Our article presents a detailed Holocene archaeological sequence from the Nile Valley at Kerma in Upper Nubia, northern Sudan. This sequence retraces the evolution of human populations thanks to the study of several sites, supported by 90 14C dates. Reconstruction of the environmental changes was supported by a study of dated stratigraphic sections located near the archaeological sites studied, and illustrates the effects on human occupation of changes in river flow and floods, which are in turn forced by climatic changes. The results shed new light on the evolutionary dynamics of the Holocene populations in Nile Valley, little known due to the numerous hiatuses in occupation. When compared with the situation in the Sahara and the rest of the Nile Valley, they confirm that the initial occupation took place ca. 10.5 kyr BP after the start of the African Humid Period, followed by a migration towards the banks of the Nile commencing 7.3 kyr BP. They also confirm the appearance of the Neolithic by ca. 8.0 kyr BP. The Kerma stratigraphic sequences show two prosperous periods (10-8 and 7-6 kyr BP) and two hiatuses in the occupation of the sites (7.5-7.1 and 6.0-5.4 kyr BP), resulting from increased aridity.

  8. RADC/NBS (Rome Air Development Center/National Bureau of Standards) Workshop. Moisture Measurement and Control for Microelectronics (4)

    Science.gov (United States)

    Kane, Didier; Moore, Benjamin A.; Walters, E. Jane

    1987-06-01

    The fourth workshop on Moisture Measurement and Control for Microelectronics served as a forum on moisture and/or materials reliability problems and on ways to control them or measure their extent. Twenty-two presentations are included which contain detailed information on hermeticity measurement and definition; development of standard packages for mass spectrometric calibrations; moisture interaction with various materials; and techniques that can be used to measure moisture microelectronics. It was clear from several presentations in the workshop that a very systematic approach is needed when organic materials are involved; all the variables must be identified and studied one at a time. This is the key to lot-to-lot reproducibility, materials selection, and control; hence a better reliability at the design phase will decrease the need for testing; hence the cost, thus resulting in a greater satisfaction to the customer.

  9. Performance Optimization of an Air-Standard Irreversible Dual-Atkinson Cycle Engine Based on the Ecological Coefficient of Performance Criterion

    Directory of Open Access Journals (Sweden)

    Guven Gonca

    2014-01-01

    Full Text Available This paper presents an ecological performance analysis and optimization for an air-standard irreversible Dual-Atkinson cycle (DAC based on the ecological coefficient of performance (ECOP criterion which includes internal irreversibilities, heat leak, and finite-rate of heat transfer. A comprehensive numerical analysis has been realized so as to investigate the global and optimal performances of the cycle. The results obtained based on the ECOP criterion are compared with a different ecological function which is named as the ecologic objective-function and with the maximum power output conditions. The results have been attained introducing the compression ratio, cut-off ratio, pressure ratio, Atkinson cycle ratio, source temperature ratio, and internal irreversibility parameter. The change of cycle performance with respect to these parameters is investigated and graphically presented.

  10. Summary of efficiency testing of standard and high-capacity high-efficiency particulate air filters subjected to simulated tornado depressurization and explosive shock waves

    International Nuclear Information System (INIS)

    Pressure transients in nuclear facility air cleaning systems can originate from natural phenomena such as tornadoes or from accident-induced explosive blast waves. This study was concerned with the effective efficiency of high-efficiency particulate air (HEPA) filters during pressure surges resulting from simulated tornado and explosion transients. The primary objective of the study was to examine filter efficiencies at pressure levels below the point of structural failure. Both standard and high-capacity 0.61-m by 0.61-m HEPA filters were evaluated, as were several 0.2-m by 0.2-m HEPA filters. For a particular manufacturer, the material release when subjected to tornado transients is the same (per unit area) for both the 0.2-m by 0.2-m and the 0.61-m by 0.61-m filters. For tornado transients, the material release was on the order of micrograms per square meter. When subjecting clean HEPA filters to simulated tornado transients with aerosol entrained in the pressure pulse, all filters tested showed a degradation of filter efficiency. For explosive transients, the material release from preloaded high-capacity filters was as much as 340 g. When preloaded high-capacity filters were subjected to shock waves approximately 50% of the structural limit level, 1 to 2 mg of particulate was released

  11. Autocorrelation standard deviation and root mean square frequency analysis of polymer electrolyte membrane fuel cell to monitor for hydrogen and air undersupply

    Science.gov (United States)

    Kim, Joo Gon; Mukherjee, Santanu; Bates, Alex; Zickel, Benjamin; Park, Sam; Son, Byung Rak; Choi, Jae Sung; Kwon, Osung; Lee, Dong Ha; Chung, Hyun-Youl

    2015-12-01

    Proton exchange membrane fuel cells are a promising energy conversion device which can help to solve urgent environmental and economic problems. Among the various types of fuel cells, the air breathing proton exchange membrane fuel cell, which minimizes the balance of plant, has drawn a lot of attention due to its superior energy density. In this study a compact, air breathing, proton exchange membrane fuel cell based on Nafion and a Pt/C membrane electrode assembly was designed. The fuel cell was tested using a Scribner Associates 850e fuel cell test station. Specifically, the hydrogen fuel and oxygen starvation of the fuel cell were accurately and systematically tested and analyzed using a frequency analysis method which can analyze the input and output frequency. The analysis of the frequency variation under a fuel starvation condition was done using RMSF (root mean square frequency) and ACSD (autocorrelation standard deviation). The study reveals two significant results: first, the fuel starvations show entirely different phenomenon in both RMSF and ACSD and second, the results of the Autocorrelation show clearer results for fuel starvation detection than the results with RMSF.

  12. Reproducibility of the airway response to an exercise protocol standardized for intensity, duration, and inspired air conditions, in subjects with symptoms suggestive of asthma

    Directory of Open Access Journals (Sweden)

    Anderson Sandra D

    2010-09-01

    Full Text Available Abstract Background Exercise testing to aid diagnosis of exercise-induced bronchoconstriction (EIB is commonly performed. Reproducibility of the airway response to a standardized exercise protocol has not been reported in subjects being evaluated with mild symptoms suggestive of asthma but without a definite diagnosis. This study examined reproducibility of % fall in FEV1 and area under the FEV1 time curve for 30 minutes in response to two exercise tests performed with the same intensity and duration of exercise, and inspired air conditions. Methods Subjects with mild symptoms of asthma exercised twice within approximately 4 days by running for 8 minutes on a motorized treadmill breathing dry air at an intensity to induce a heart rate between 80-90% predicted maximum; reproducibility of the airway response was expressed as the 95% probability interval. Results Of 373 subjects challenged twice 161 were positive (≥10% fall FEV1 on at least one challenge. The EIB was mild and 77% of subjects had 1 and 19.3% (72 positive on both challenges. The remaining 23.9% of subjects had only one positive test. The 95% probability interval for reproducibility of the % fall in FEV1 and AUC0-30 min was ± 9.7% and ± 251% for all 278 adults and ± 13.4% and ± 279% for all 95 children. The 95% probability interval for reproducibility of % fall in FEV1 and AUC0-30 min for the 72 subjects with two tests ≥10% fall FEV1 was ± 14.6% and ± 373% and for the 34 subjects with two tests ≥15% fall FEV1 it was ± 12.2% and ± 411%. Heart rate and estimated ventilation achieved were not significantly different either on the two test days or when one test result was positive and one was negative. Conclusions Under standardized, well controlled conditions for exercise challenge, the majority of subjects with mild symptoms of asthma demonstrated agreement in test results. Performing two tests may need to be considered when using exercise to exclude or diagnose EIB, when

  13. Balancing energy conservation and occupant needs in ventilation rate standards for Big Box stores and other commercial buildings in California. Issues related to the ASHRAE 62.1 Indoor Air Quality Procedure

    Energy Technology Data Exchange (ETDEWEB)

    Mendell, Mark J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Apte, Mike G. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2010-10-31

    This report considers the question of whether the California Energy Commission should incorporate the ASHRAE 62.1 ventilation standard into the Title 24 ventilation rate (VR) standards, thus allowing buildings to follow the Indoor Air Quality Procedure. This, in contrast to the current prescriptive standard, allows the option of using ventilation rate as one of several strategies, which might include source reduction and air cleaning, to meet specified targets of indoor air concentrations and occupant acceptability. The research findings reviewed in this report suggest that a revised approach to a ventilation standard for commercial buildings is necessary, because the current prescriptive ASHRAE 62.1 Ventilation Rate Procedure (VRP) apparently does not provide occupants with either sufficiently acceptable or sufficiently healthprotective air quality. One possible solution would be a dramatic increase in the minimum ventilation rates (VRs) prescribed by a VRP. This solution, however, is not feasible for at least three reasons: the current need to reduce energy use rather than increase it further, the problem of polluted outdoor air in many cities, and the apparent limited ability of increasing VRs to reduce all indoor airborne contaminants of concern (per Hodgson (2003)). Any feasible solution is thus likely to include methods of pollutant reduction other than increased outdoor air ventilation; e.g., source reduction or air cleaning. The alternative 62.1 Indoor Air Quality Procedure (IAQP) offers multiple possible benefits in this direction over the VRP, but seems too limited by insufficient specifications and inadequate available data to provide adequate protection for occupants. Ventilation system designers rarely choose to use it, finding it too arbitrary and requiring use of much non-engineering judgment and information that is not readily available. This report suggests strategies to revise the current ASHRAE IAQP to reduce its current limitations. These

  14. Airing It Out.

    Science.gov (United States)

    Fitzemeyer, Ted

    2000-01-01

    Discusses how proper maintenance can help schools eliminate sources contributing to poor air quality. Maintaining heating and air conditioning units, investigating bacterial breeding grounds, fixing leaking boilers, and adhering to ventilation codes and standards are discussed. (GR)

  15. Analytic And Monte Carlo Study Of The Perturbation Factor kp For A Standard Of Dw Through An Ka Standard Ionization Chamber BEV-CC01

    International Nuclear Information System (INIS)

    To characterize an ionization chamber BEV-CC01 as a standard of absorbed dose to water Dw at SSDL-Mexico, the approach developed by the BIPM for 60Co gamma radiation, has been chosen. This requires the estimation of a factor kp, which stems from the perturbation introduced by the presence of the ionization chamber in the water phantom, and due to finite size of the cavity. This factor is the product of four terms: ψw,c (μen/ρ)w,c (1 + μ'.y-bar)w,c and kcav. Two independent determinations are accomplished using a combination of the Monte Carlo code MCNP4C in ITS mode [2,3] and analytic methods: one kp parallel =1.1626 ± uc=: 0.90% for the chamber axis parallel to the beam axis; and another kp =1.1079± uc=0.89% for the chamber axis perpendicular to the beam axis. The variance reduction techniques: splitting-Russian roulette, source biasing and forced photon collisions are employed in the simulations to improve the calculation efficiency. The energy fluence for the 60Co housing-source Picker C/9 is obtained by realistic Monte Carlo (MC) simulation, it is verified by comparison of MC calculated and measured beam output air kerma factors, and percent depth dose curves in water, PDD. This spectrum is considered as input energy for a point source (74% is from primary photons and the rest 26% is from scattered radiation) in the determination of the kp factors. Details of the calculations are given together with the theoretical basis of the ionometric standard employed

  16. Enlightenment to Chinese Air Force of USAF medical selection standard system of flying cadets%美国空军飞行学员医学选拔标准体系及其对我军的启示

    Institute of Scientific and Technical Information of China (English)

    邹志康; 张凌; 王广云; 孙金杰; 夏青; 刘伟; 吉保民; 马中立

    2016-01-01

    系统了解美国空军飞行学员医学选拔标准情况,全面总结美国空军飞行学员医学选拔标准体系和内容,为我军飞行学员医学选拔标准修订和执行提供参考依据.系统分析美国空军4个飞行学员相关医学选拔标准,对照我军飞行学员医学选拔标准,提出美国空军飞行学员医学选拔标准及持续改进的特点内容,归纳我军飞行学员医学选拔优势和需要改进的主要内容.美国空军飞行学员医学选拔标准体系由《国防部指令》《空军体格检查和标准》《空军医学标准指导》《空军特许飞行指南》4个相互引用、相互补充的标准共同构成,具体指标的制订依据来源于航空医学要求和军事训练需要,修改频率很快,整体上更加突出功能需求,与我军飞行学员医学选拔标准相比体系更完善,形态要求更低、功能评价技术更为先进,放飞和停飞依据更为充分.参照美军标准制订的原则和依据开展相应的科学研究,对眼科、外科等生源影响较大、飞行影响较小的一些标准进行针对性修改,完善相关医学选拔技术手段,对扩大招飞优质生源、提升招飞整体质量具有重要意义.%To review the American medical standards of recruiting student pilots, and summarise the features procedures, requirements, and medical standards for medical examinations given by the American Air Force, offer evidence to revise Chinese Air force medical standards of recruiting student pilots. By metrieving literature in this field from medical bibliographic database and foreign military official websites, four published reports and network information were cited, compared with the Chinese Air force medical standards, to find out the differences between the two standards. The American medical standards include Department of Defense Instruction, Air Force Medical Examination and Standards, Air Force Medical Standards Directory, and Air Force Waiver Guide

  17. X射线环境水平标准装置的研究与建立%The establishment of x-ray environmental standard calibration quality

    Institute of Scientific and Technical Information of China (English)

    欧向明; 赵士庵; 丁艳秋

    2014-01-01

    Objective:According to the requirement of ISO and National Standard, new X-ray environmental standard for the calibration of environmental dosimeter was established in Beijing SSDL. Methods:Half value layer and air kerma dose-rate was determined in the X-ray environmental qualities by a standard dosimeter. Results: The technical requirement of ISO and National Standard are met within 2% for the X-ray environmental standard qualities in Beijing SSDL. Conclusion:The X-ray standard radiation field can be used for the calibration of environmental dosimeters and experiment of research.%目的:按照国际标准化组织(ISO)技术规范及我国现行国家标准的相关要求,在国家二级标准剂量学实验室建立用于校准X射线环境水平剂量仪的标准装置。方法:通过标准剂量仪测量不同附加过滤后的X射线束的衰减,测定标准辐射场常用的半值层及空气比释动能率,确定环境水平X射线辐射线质的有效能量和平均能量。结果:测定的辐射线质等参数与ISO和国家标准给出的技术指标误差<2%,满足标准装置的要求。结论:建立的X射线环境水平标准装置可以用于校准环境水平辐射剂量仪、并为开展相关的研究工作提供实验条件。

  18. Conception and realization of a parallel-plate free-air ionization chamber for the absolute dosimetry of an ultrasoft X-ray beam

    Energy Technology Data Exchange (ETDEWEB)

    Groetz, J.-E., E-mail: jegroetz@univ-fcomte.fr; Mavon, C.; Fromm, M. [Laboratoire Chrono-Environnement, UMR CNRS 6249, Université de Franche-Comté, 16 route de Gray, 25030 Besançon Cedex (France); Ounoughi, N. [Laboratoire Chrono-Environnement, UMR CNRS 6249, Université de Franche-Comté, 16 route de Gray, 25030 Besançon Cedex (France); Laboratoire de Physique des Rayonnements et Applications, Université de Jijel, B.P. 98 Ouled Aissa, Jijel 18000 (Algeria); Belafrites, A. [Laboratoire de Physique des Rayonnements et Applications, Université de Jijel, B.P. 98 Ouled Aissa, Jijel 18000 (Algeria)

    2014-08-15

    We report the design of a millimeter-sized parallel plate free-air ionization chamber (IC) aimed at determining the absolute air kerma rate of an ultra-soft X-ray beam (E = 1.5 keV). The size of the IC was determined so that the measurement volume satisfies the condition of charged-particle equilibrium. The correction factors necessary to properly measure the absolute kerma using the IC have been established. Particular attention was given to the determination of the effective mean energy for the 1.5 keV photons using the PENELOPE code. Other correction factors were determined by means of computer simulation (COMSOL™and FLUKA). Measurements of air kerma rates under specific operating parameters of the lab-bench X-ray source have been performed at various distances from that source and compared to Monte Carlo calculations. We show that the developed ionization chamber makes it possible to determine accurate photon fluence rates in routine work and will constitute substantial time-savings for future radiobiological experiments based on the use of ultra-soft X-rays.

  19. Conception and realization of a parallel-plate free-air ionization chamber for the absolute dosimetry of an ultrasoft X-ray beam

    Science.gov (United States)

    Groetz, J.-E.; Ounoughi, N.; Mavon, C.; Belafrites, A.; Fromm, M.

    2014-08-01

    We report the design of a millimeter-sized parallel plate free-air ionization chamber (IC) aimed at determining the absolute air kerma rate of an ultra-soft X-ray beam (E = 1.5 keV). The size of the IC was determined so that the measurement volume satisfies the condition of charged-particle equilibrium. The correction factors necessary to properly measure the absolute kerma using the IC have been established. Particular attention was given to the determination of the effective mean energy for the 1.5 keV photons using the PENELOPE code. Other correction factors were determined by means of computer simulation (COMSOL™and FLUKA). Measurements of air kerma rates under specific operating parameters of the lab-bench X-ray source have been performed at various distances from that source and compared to Monte Carlo calculations. We show that the developed ionization chamber makes it possible to determine accurate photon fluence rates in routine work and will constitute substantial time-savings for future radiobiological experiments based on the use of ultra-soft X-rays.

  20. Technical support document: Energy efficiency standards for consumer products: Room air conditioners, water heaters, direct heating equipment, mobile home furnaces, kitchen ranges and ovens, pool heaters, fluorescent lamp ballasts and television sets. Volume 1, Methodology

    Energy Technology Data Exchange (ETDEWEB)

    1993-11-01

    The Energy Policy and Conservation Act (P.L. 94-163), as amended, establishes energy conservation standards for 12 of the 13 types of consumer products specifically covered by the Act. The legislation requires the Department of Energy (DOE) to consider new or amended standards for these and other types of products at specified times. DOE is currently considering amending standards for seven types of products: water heaters, direct heating equipment, mobile home furnaces, pool heaters, room air conditioners, kitchen ranges and ovens (including microwave ovens), and fluorescent light ballasts and is considering establishing standards for television sets. This Technical Support Document presents the methodology, data, and results from the analysis of the energy and economic impacts of the proposed standards. This volume presents a general description of the analytic approach, including the structure of the major models.

  1. A Prototype Ionisation Chamber as a Secondary Standard for the Measurement of Personal Dose Equivalent, Hp(10), on a Slab Phantom

    International Nuclear Information System (INIS)

    The construction and technical characteristics of a secondary standard chamber for measuring the conventionally true value of the personal dose equivalent, Hp(10), on a slab phantom are presented. The chamber was optimised to get a nearly constant response with respect to Hp(10) for photon energies from about 10 keV to 1400 keV and for angles of incidence, alpha, from 0 deg. to 75 deg. . Thus, once calibrated at the facility of the calibration laboratory, the Hp(10) chamber can be used at other facilities without any need to consider the spectral differences of radiation fields of the same nominal radiation quality but generated by two different facilities. This is a great advantage over the procedure recommended in ISO/FDIS 4037-3, according to which these differences have to be considered for low energy photon radiation and may lead to differences of the conversion coefficients from air kerma, Ka, to Hp(10) of up to several tens of per cent. (author)

  2. Calculation of conversion coefficients Hp(3)/K air using the PENELOPE Monte Carlo code and comparison with MCNP calculation results

    International Nuclear Information System (INIS)

    The authors report calculations performed using the MNCP and PENELOPE codes to determine the Hp(3)/K air conversion coefficient which allows the Hp(3) dose equivalent to be determined from the measured value of the kerma in the air. They report the definition of the phantom, a 20 cm diameter and 20 cm high cylinder which is considered as representative of a head. Calculations are performed for an energy range corresponding to interventional radiology or cardiology (20 keV-110 keV). Results obtained with both codes are compared

  3. Advisory Committee for the Calibration Standards of Ionizing Radiation Measurement

    International Nuclear Information System (INIS)

    An account of the activity during the past two years and of the plans for future work is given for the three Sections of the Comite Consultatif pour les Etalons de Mesure des Rayonnements Ionisants. Section I (Rayons X et #betta#, electrons) studied in detail the results of an intercomparison of Frike dosimeters. A recommendation was made concerning the possibility of expressing calibrations made in terms of exposure in terms of air kerma or water kerma. Section II (Mesure des radionucleides) studied the results of recent international comparisons (55Fe, 133Ba and 134Cs) and made plans for new ones. Section III (Mesures neutroniques) presented the status of the international comparisons of neutron fluence rate in progress and decided to organize new ones. The reports of the Section chairmen are followed by the presentation of the work carried out at BIPM by the corresponding groups. The status of the proposal by Section III for a 14 MeV neutron dosimetry facility at BIPM is discussed in detail and a proposal is made for a neutron dosimetry intercomparison

  4. An air quality data analysis system for interrelating effects, standards, and needed source reductions: Part 12. Effects on man, animals, and plants as a function of air pollutant impact.

    Science.gov (United States)

    Larsen, R I; McDonnell, W F; Coffin, D L; Heck, W W

    1993-12-01

    The impact-effect mathematical model, developed in 1991, improves on a previous mathematical model, and was developed to predict biological response as a function of air pollutant impact. Impact is defined here as exposure duration multiplied by air pollutant concentration raised to an exponent (t.cd). This paper's purpose is to plot and regress example biological effects as a function of air pollutant impact to determine how well the plotted data fit the impact-effect model for three target populations: man, animals, and plants (a wide range of life forms). The three biological effects are: for man, lung function decrease after exposure to ozone (O3); for animals, mouse mortality after exposure to nitrogen dioxide (NO2); and for plants, leaf injury after exposure to O3. The three resultant regression equations account for a substantial amount of the data variance: 95 percent for lung function, 92 percent for leaf injury, and 73 percent for mouse mortality. The model fits the animal and plant data that cover both acute and chronic exposures. The animal exposures ranged from 6 min to 1 yr. The plant exposures ranged from 0.75 to 552 h.

  5. Determination of the diaphragm correction factor of the LNE-LNHB free-air chambers for low and medium energy X-rays

    International Nuclear Information System (INIS)

    Until recently, in the establishment of the French LNE-LNHB national reference in terms of air kerma for low and medium energy X-rays, the effect of the diaphragm located at the entrance of the free-air ionization chambers was not sufficiently taken into account. This report describes the different Monte Carlo computations made in 2010-2011 with the PENELOPE Monte Carlo code to determine a correction factor (kdia) describing the influence of the different incident photon interactions taking place into the diaphragm on the deposited energy in the collecting volume. (author)

  6. Preparation of standard mixtures of gas hydrocarbons in air by the diffusion dilution method; Preparacion de mezclas patrones de hidrocarburos gaseosos en aire por el metodo de dilucion por difusion

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, M. R.; Perez, M. M.

    1979-07-01

    An original diffusion system able to produce continuously gaseous samples is described. This system can generate samples with concentrations of benzene in air from 0.1 to 1 ppm a reproducible way. The diffusion dilution method used Is also studied. The use of this diffusion system has been extended to the preparation of binary mixtures (benzene-toluene). Whit a secondary dilution device is possible preparing these mixtures over a wide range of concentrations (0.11 to 0.04 ppm for benzene and 0.06 to 0.02 for toluene). (Author) 7 refs.

  7. Impact of ASTM Standard E722 update on radiation damage metrics.

    Energy Technology Data Exchange (ETDEWEB)

    DePriest, Kendall Russell

    2014-06-01

    The impact of recent changes to the ASTM Standard E722 is investigated. The methodological changes in the production of the displacement kerma factors for silicon has significant impact for some energy regions of the 1-MeV(Si) equivalent fluence response function. When evaluating the integral over all neutrons energies in various spectra important to the SNL electronics testing community, the change in the response results in an increase in the total 1-MeV(Si) equivalent fluence of 2 7%. Response functions have been produced and are available for users of both the NuGET and MCNP codes.

  8. Analysis of energy dependence of the film radiochromic XRQA2 for seven spectra of X-ray standard in diagnostic radiology; Analisis de la dependencia energetica de la pelicula radiogromica XRQA2 para siete espectros de rayos X habituales en radiodiagnostico

    Energy Technology Data Exchange (ETDEWEB)

    Vicent Granado, D.; Gutierrez Ramos, S. M.; Sanchez Carmona, G.; Santos Rubio, A. J.; Herrador Cordoba, M.

    2013-07-01

    The response of the radiochromic film XRQA2 depends on the peak voltage, as well as filtration and measurement with or without backscatter. The common method of using a calibration from the kerma in air to measure the dose at the entrance of patients is not the most advisable for this film in this dose range. Whenever possible should be the calibration with the spectrum of X rays for which will be the measurement of absorbed dose. (Author)

  9. Air Pollution

    Science.gov (United States)

    Air pollution is a mixture of solid particles and gases in the air. Car emissions, chemicals from factories, dust, pollen and ... Ozone, a gas, is a major part of air pollution in cities. When ozone forms air pollution, ...

  10. Assessment of corrective factors for the LNHB reference measurement in terms of Kr air for iodine 125; Evaluation des facteurs de correction a apporter a la mesure de la reference LNHB en termes de k{sub r} air pour l'iode 125

    Energy Technology Data Exchange (ETDEWEB)

    Gouriou, J.; Aubineau-Laniece, I.; Cutarella, D.; Plagnard, J. [CEA Saclay, LIST, Laboratoire National Henri Becquerel (LNE-LNHB), 91 - Gif-sur-Yvette (France)

    2010-07-01

    The LNHB (Laboratoire National Henri Becquerel) is currently developing a new primary reference for low dose rate curietherapy with iodine 125 in terms of reference kerma in air. This includes an innovative sensor: an ionization chamber with a toroidal air wall. The authors present Monte Carlo calculations performed for the determination of corrective factors to be applied to come down to reference conditions or to correct possible measurement errors. Calculations have been performed for the specific geometries of BEBIG sources which are used for ophthalmic and prostatic curietherapy treatments

  11. 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.)

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

    International Nuclear Information System (INIS)

    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.)

  13. Air Pollution Affects Community Health

    Science.gov (United States)

    Shy, Carl M.; Finklea, John F.

    1973-01-01

    Community Health and Environmental Surveillance System (CHESS), a nationwide program relating community health to environmental quality, is designed to evaluate existing environmental standards, obtain health intelligence for new standards, and document health benefits of air pollution control. (BL)

  14. Development of standardized air-blown coal gasifier/gas turbine concepts for future electric power systems. Volume 5, Appendix D: Cost support information: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Sadowski, R.S.; Brown, M.J.; Harriz, J.T.; Ostrowski, E.

    1991-01-01

    The cost estimate provided for the DOE sponsored study of Air Blown Coal Gasification was developed from vendor quotes obtained directly for the equipment needed in the 50 MW, 100 MW, and 200 MW sized plants and from quotes from other jobs that have been referenced to apply to the particular cycle. Quotes were generally obtained for the 100 MW cycle and a scale up/down factor was used to generate the cost estimates for the 200 MW and 50 MW cycles, respectively. Information from GTPro (property of Thermoflow, Inc.) was used to estimate the cost of the 200 MW and 50 MW gas turbine, HRSG, and steam turbines. To available the use of GTPro`s estimated values for this equipment, a comparison was made between the quotes obtained for the 100 MW cycle (ABB GT 11N combustion turbine and a HSRG) against the estimated values by GTPro.

  15. Final Report Balancing energy conservation and occupant needs in ventilation rate standards for Big Box stores in California. Predicted indoor air quality and energy consumption using a matrix of ventilation scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Apte, Michael G. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mendell, Mark J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sohn, Michael D. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Dutton, Spencer M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Berkeley, Pam M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Spears, Michael [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2011-02-01

    Through mass-balance modeling of various ventilation scenarios that might satisfy the ASHRAE 62.1 Indoor Air Quality (IAQ) Procedure, we estimate indoor concentrations of contaminants of concern (COCs) in California “big box” stores, compare estimates to available thresholds, and for selected scenarios estimate differences in energy consumption. Findings are intended to inform decisions on adding performance-based approaches to ventilation rate (VR) standards for commercial buildings. Using multi-zone mass-balance models and available contaminant source rates, we estimated concentrations of 34 COCs for multiple ventilation scenarios: VRmin (0.04 cfm/ft2 ), VRmax (0.24 cfm/ft2 ), and VRmid (0.14 cfm/ft2 ). We compared COC concentrations with available health, olfactory, and irritant thresholds. We estimated building energy consumption at different VRs using a previously developed EnergyPlus model. VRmax did control all contaminants adequately, but VRmin did not, and VRmid did so only marginally. Air cleaning and local ventilation near strong sources both showed promise. Higher VRs increased indoor concentrations of outdoor air pollutants. Lowering VRs in big box stores in California from VRmax to VRmid would reduce total energy use by an estimated 6.6% and energy costs by 2.5%. Reducing the required VRs in California’s big box stores could reduce energy use and costs, but poses challenges for health and comfort of occupants. Source removal, air cleaning, and local ventilation may be needed at reduced VRs, and even at current recommended VRs. Also, alternative ventilation strategies taking climate and season into account in ventilation schedules may provide greater energy cost savings than constant ventilation rates, while improving IAQ.

  16. In-situ calibration of clinical built-in KAP meters with traceability to a primary standard using a reference KAP meter

    Science.gov (United States)

    Malusek, A.; Helmrot, E.; Sandborg, M.; Grindborg, J.-E.; Alm Carlsson, G.

    2014-12-01

    The air kerma-area product (KAP) is used for settings of diagnostic reference levels. The International Atomic Energy Agency (IAEA) recommends that doses in diagnostic radiology (including the KAP values) be estimated with an accuracy of at least ±7% (k = 2). Industry standards defined by the International Electrotechnical Commission (IEC) specify that the uncertainty of KAP meter measurements should be less than +/- 25% (k = 2). Medical physicists willing to comply with the IAEA’s recommendation need to apply correction factors to KAP values reported by x-ray units. The aim of this work is to present and evaluate a calibration method for built-in KAP meters on clinical x-ray units. The method is based on (i) a tandem calibration method, which uses a reference KAP meter calibrated to measure the incident radiation, (ii) measurements using an energy-independent ionization chamber to correct for the energy dependence of the reference KAP meter, and (iii) Monte Carlo simulations of the beam quality correction factors that correct for differences between beam qualities at a standard laboratory and the clinic. The method was applied to the KAP meter in a Siemens Aristos FX plus unit. It was found that values reported by the built-in KAP meter differed from the more accurate values measured by the reference KAP meter by more than 25% for high tube voltages (more than 140 kV) and heavily filtered beams (0.3 mm Cu). Associated uncertainties were too high to claim that the IEC’s limit of 25% was exceeded. Nevertheless the differences were high enough to justify the need for a more accurate calibration of built-in KAP meters.

  17. Experiencias de la instauración de normas relativas al contenido de plomo en aire y el agua, en los Estados Unidos de América Establishing lead in air and water standards in the United States of America

    Directory of Open Access Journals (Sweden)

    J Michael Davis

    2003-01-01

    Full Text Available En los Estados Unidos de América se ha logrado una disminución de la exposición a plomo de la población en general, gracias al establecimiento de diversas normas. En este artículo se destaca parte de los conocimientos adquiridos a través de la experiencia obtenida en este país en materia de plomo, en particular respecto al aire y al agua. Uno de los aspectos fundamentales es la posibilidad de contar con una base científica sólidamente establecida y claramente entendida, a partir de la cual se tomarán las medidas correspondientes. Los efectos secundarios de ciertas normas concernientes al aire ponen de manifiesto de qué manera los esfuerzos orientados a solucionar un problema pueden aportar beneficios en otras áreas, si bien pueden surgir consecuencias no deseadas, debido a la falta de previsión y de evaluación. Asimismo, en este documento se discuten las diferencias entre los enfoques centralizados y los descentralizados para el manejo de la exposición a plomo.Lead regulations and standards have resulted in a lower exposure to lead in the general population of the United States of America. This paper highlights some of the know-how developed through lead-containing experiences, particularly regarding lead content in air and water. The availability of a solid and clear scientific knowledge is central to the success of these policies. Collateral effects of some air-related standards show the extent to which problem-oriented efforts may be beneficial in other areas, inasmuch as they may have untoward consequences if careful planning and evaluation are not considered. Finally, this paper presents a discussion of the differences between centralized and decentralized approaches to lead exposure control.

  18. 77 FR 12482 - Approval and Promulgation of Air Quality Implementation Plans; Indiana; Lead Ambient Air Quality...

    Science.gov (United States)

    2012-03-01

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of Air Quality Implementation Plans; Indiana; Lead Ambient Air Quality Standards AGENCY: Environmental Protection Agency (EPA). ACTION: Direct final rule... Clean Air Act (CAA). This submittal incorporates the National Ambient Air Quality Standards (NAAQS)...

  19. 40 CFR 63.322 - Standards.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Standards. 63.322 Section 63.322... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES National Perchloroethylene Air Emission Standards for Dry Cleaning Facilities § 63.322 Standards. (a) The owner or operator of...

  20. 40 CFR 61.222 - Standard.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Standard. 61.222 Section 61.222... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standards for Radon Emissions From the Disposal of Uranium Mill Tailings § 61.222 Standard. (a) Radon-222 emissions to the ambient air...

  1. 40 CFR 63.402 - Standard.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Standard. 63.402 Section 63.402... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES National Emission Standards for Hazardous Air Pollutants for Industrial Process Cooling Towers § 63.402 Standard. No owner or operator of...

  2. 40 CFR 61.22 - Standard.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Standard. 61.22 Section 61.22... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standards for Radon Emissions From Underground Uranium Mines § 61.22 Standard. Emissions of radon-222 to the ambient air from an...

  3. 40 CFR 61.102 - Standard.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Standard. 61.102 Section 61.102... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standards for Radionuclide Emissions From....102 Standard. (a) Emissions of radionuclides, including iodine, to the ambient air from a...

  4. Development of standardized air-blown coal gasifier/gas turbine concepts for future electric power systems. Volume 2, Appendix A: Fixed bed gasifier and sulfur sorbent regeneration subsystem computer model development: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Blough, E.; Russell, W.; Leach, J.W.

    1990-08-01

    Computer models have been developed for evaluating conceptual designs of integrated coal gasification combined cycle power plants. An overall system model was developed for performing thermodynamic cycle analyses, and detailed models were developed for predicting performance characteristics of fixed bed coal gasifiers and hot gas clean up subsystem components. The overall system model performs mass and energy balances and does chemical equilibrium analyses to determine the effects of changes in operating conditions, or to evaluate proposed design changes. An existing plug flow model for fixed bed gasifiers known as the Wen II model was revised and updated. Also, a spread sheet model of zinc ferrite sulfur sorbent regeneration subsystem was developed. Parametric analyses were performed to determine how performance depends on variables in the system design. The work was done to support CRS Sirrine Incorporated in their study of standardized air blown coal gasifier gas turbine concepts.

  5. Air Abrasion

    Science.gov (United States)

    ... delivered directly to your desktop! more... What Is Air Abrasion? Article Chapters What Is Air Abrasion? What Happens? The Pros and Cons Will I Feel Anything? Is Air Abrasion for Everyone? print full article print this ...

  6. 空气净化产品净化效果的标准测试方法%Discussion about the standard test method of puriifcation efifciency of air cleaner

    Institute of Scientific and Technical Information of China (English)

    钱明媛; 张晓波

    2014-01-01

    This research analysis the difference between the purification efficiency measured by using the test method in the product standard and the purification efficiency in the actual application, and verification the significant differences between the two efficiency with the test. The research put forward many factors what affect the efficiency of the air purification products and the direction of the air purification products what can be improved in the future.%分析了空气净化产品标准中产品净化效率测试方法所测得净化效率,与产品在实际应用中净化效率的区别。实验验证两者之间的显著差异,提出影响净化产品净化效率的多种因素以及将来空气净化产品可以完善的方向。

  7. SU-F-19A-02: Comparison of Absorbed Dose to Water Standards for HDR Ir-192 Brachytherapy Between the LCR, Brazil and NRC, Canada

    Energy Technology Data Exchange (ETDEWEB)

    Salata, C; David, M; Almeida, C de [Universidade do Estado do Rio de Janeiro, Rio De Janeiro, RJ (Brazil); El Gamal, I; Cojocaru, C; Mainegra-Hing, E; McEwen, M [National Research Council, Ottawa, ON (Canada)

    2014-06-15

    Purpose: To compare absorbed dose to water standards for HDR brachytherapy dosimetry developed by the Radiological Science Laboratory of Rio de Janeiro State University (LCR) and the National Research Council, Canada (NRC). Methods: The two institutions have separately developed absorbed dose standards based on the Fricke dosimetry system. There are important differences between the two standards, including: preparation and read-out of the Fricke solution, irradiation geometry of the Fricke holder in relation to the Ir-192 source, and determination of the G-value to be used at Ir-192 energies. All measurements for both standards were made directly at the NRC laboratory (i.e., no transfer instrument was used) using a single Ir-192 source (microSelectron v2). In addition, the NRC group has established a self-consistent method to determine the G-value for Ir-192, based on an interpolation between G-values obtained at Co-60 and 250kVp X-rays, and this measurement was repeated using the LCR Fricke solution to investigate possible systematic uncertainties. Results: G-values for Co-60 and 250 kVp x-rays, obtained using the LCR Fricke system, agreed with the NRC values within 0.5 % and 1 % respectively, indicating that the general assumption of universal G-values is appropriate in this case. The standard uncertainty in the determination of G for Ir-192 is estimated to be 0.6 %. For the comparison of absorbed dose measurements at the reference point for Ir-192 (1 cm depth in water, perpendicular to the seed long-axis), the ratio Dw(NRC)/Dw(LCR) was found to be 1.011 with a combined standard uncertainty of 1.7 %, k=1. Conclusion: The agreement in the absorbed dose to water values for the LCR and NRC systems is very encouraging. Combined with the lower uncertainty in this approach compared to the present air-kerma approach, these results reaffirm the use of Fricke solution as a potential primary standard for HDR Ir-192 brachytherapy.

  8. SU-F-19A-02: Comparison of Absorbed Dose to Water Standards for HDR Ir-192 Brachytherapy Between the LCR, Brazil and NRC, Canada

    International Nuclear Information System (INIS)

    Purpose: To compare absorbed dose to water standards for HDR brachytherapy dosimetry developed by the Radiological Science Laboratory of Rio de Janeiro State University (LCR) and the National Research Council, Canada (NRC). Methods: The two institutions have separately developed absorbed dose standards based on the Fricke dosimetry system. There are important differences between the two standards, including: preparation and read-out of the Fricke solution, irradiation geometry of the Fricke holder in relation to the Ir-192 source, and determination of the G-value to be used at Ir-192 energies. All measurements for both standards were made directly at the NRC laboratory (i.e., no transfer instrument was used) using a single Ir-192 source (microSelectron v2). In addition, the NRC group has established a self-consistent method to determine the G-value for Ir-192, based on an interpolation between G-values obtained at Co-60 and 250kVp X-rays, and this measurement was repeated using the LCR Fricke solution to investigate possible systematic uncertainties. Results: G-values for Co-60 and 250 kVp x-rays, obtained using the LCR Fricke system, agreed with the NRC values within 0.5 % and 1 % respectively, indicating that the general assumption of universal G-values is appropriate in this case. The standard uncertainty in the determination of G for Ir-192 is estimated to be 0.6 %. For the comparison of absorbed dose measurements at the reference point for Ir-192 (1 cm depth in water, perpendicular to the seed long-axis), the ratio Dw(NRC)/Dw(LCR) was found to be 1.011 with a combined standard uncertainty of 1.7 %, k=1. Conclusion: The agreement in the absorbed dose to water values for the LCR and NRC systems is very encouraging. Combined with the lower uncertainty in this approach compared to the present air-kerma approach, these results reaffirm the use of Fricke solution as a potential primary standard for HDR Ir-192 brachytherapy

  9. Comparison of DVH parameters and loading patterns of standard loading, manual and inverse optimization for intracavitary brachytherapy on a subset of tandem/ovoid cases

    International Nuclear Information System (INIS)

    Purpose: Comparison of inverse planning with the standard clinical plan and with the manually optimized plan based on dose-volume parameters and loading patterns. Materials and methods: Twenty-eight patients who underwent MRI based HDR brachytherapy for cervix cancer were selected for this study. Three plans were calculated for each patient: (1) standard loading, (2) manual optimized, and (3) inverse optimized. Dosimetric outcomes from these plans were compared based on dose-volume parameters. The ratio of Total Reference Air Kerma of ovoid to tandem (TRAKO/T) was used to compare the loading patterns. Results: The volume of HR CTV ranged from 9-68 cc with a mean of 41(±16.2)cc. Mean V100 for standard, manual optimized and inverse plans was found to be not significant (p = 0.35, 0.38, 0.4). Dose to bladder (7.8 ± 1.6 Gy) and sigmoid (5.6 ± 1.4 Gy) was high for standard plans; Manual optimization reduced the dose to bladder (7.1 ± 1.7 Gy p = 0.006) and sigmoid (4.5 ± 1.0 Gy p = 0.005) without compromising the HR CTV coverage. The inverse plan resulted in a significant reduction to bladder dose (6.5 ± 1.4 Gy, p = 0.002). TRAK was found to be 0.49(±0.02), 0.44(±0.04) and 0.40(±0.04)cGy m-2 for the standard loading, manual optimized and inverse plans, respectively. It was observed that TRAKO/T was 0.82(±0.05), 1.7(±1.04) and 1.41(±0.93) for standard loading, manual optimized and inverse plans, respectively, while this ratio was 1 for the traditional loading pattern. Conclusions: Inverse planning offers good sparing of critical structures without compromising the target coverage. The average loading pattern of the whole patient cohort deviates from the standard Fletcher loading pattern.

  10. 49 CFR 570.57 - Air brake system and air-over-hydraulic brake subsystem.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 6 2010-10-01 2010-10-01 false Air brake system and air-over-hydraulic brake... STANDARDS Vehicles With GVWR of More Than 10,000 Pounds § 570.57 Air brake system and air-over-hydraulic brake subsystem. The following requirements apply to vehicles with air brake and...

  11. Technical and Economic Analysis on the New Emission Standard of Air Pollutants for Thermal Power Plants%火电厂大气污染物排放新标准的技术经济分析

    Institute of Scientific and Technical Information of China (English)

    付蓉

    2011-01-01

    Based on the comparison between the new and the old emission standards of air pollutants for thermal power plants, this paper analyzes the capacity of the thermal power generation units which need to be renovated by increasing the functions of de-dusting, desulfurization and denitrification in order to meet the new standard, and discusses the technology that is used to conduct the renovation. Considering the forecast of the development of electricity, the study also calculates the environmental investment and the operating cost of the existing and the new-built units, and puts forward relevant suggestions.%在火电厂大气污染物排放新、老标准比较的基础上,分析了现有机组需要进行除尘、脱硫和脱硝的改造容量及改造技术,结合“十二五”电力发展预测,测算了“十二五”期间火电行业现有机组及新建机组的环保投入和运行费用,并提出相关对策。

  12. 75 FR 34673 - Approval of the Clean Air Act, Section 112(l), Authority for Hazardous Air Pollutants: Air...

    Science.gov (United States)

    2010-06-18

    ... AGENCY 40 CFR Part 63 Approval of the Clean Air Act, Section 112(l), Authority for Hazardous Air Pollutants: Air Emission Standards for Halogenated Solvent Cleaning Machines: State of Rhode Island... Emissions from Organic Solvent Cleaning (``RI Regulation No. 36'') and Rhode Island Air Pollution...

  13. Applications Using AIRS Data

    Science.gov (United States)

    Ray, S. E.; Pagano, T. S.; Fetzer, E. J.; Lambrigtsen, B.; Olsen, E. T.; Teixeira, J.; Licata, S. J.; Hall, J. R.; Thompson, C. K.

    2015-12-01

    The Atmospheric Infrared Sounder (AIRS) on NASA's Aqua spacecraft has been returning daily global observations of Earth's atmospheric constituents and properties since 2002. With a 12-year data record and daily, global observations in near real-time, AIRS data can play a role in applications that fall under many of the NASA Applied Sciences focus areas. For vector-borne disease, research is underway using AIRS near surface retrievals to assess outbreak risk, mosquito incubation periods and epidemic potential for dengue fever, malaria, and West Nile virus. For drought applications, AIRS temperature and humidity data are being used in the development of new drought indicators and improvement in the understanding of drought development. For volcanic hazards, new algorithms using AIRS data are in development to improve the reporting of sulfur dioxide concentration, the burden and height of volcanic ash and dust, all of which pose a safety threat to aircraft. In addition, anomaly maps of many of AIRS standard products are being produced to help highlight "hot spots" and illustrate trends. To distribute it's applications imagery, AIRS is leveraging existing NASA data frameworks and organizations to facilitate archiving, distribution and participation in the BEDI. This poster will communicate the status of the applications effort for the AIRS Project and provide examples of new maps designed to best communicate the AIRS data.

  14. 30 CFR 75.321 - Air quality.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Air quality. 75.321 Section 75.321 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Ventilation § 75.321 Air quality. (a)(1) The air in areas where... air current in these areas shall be sufficient to dilute, render harmless, and carry away...

  15. 40 CFR 63.642 - General standards.

    Science.gov (United States)

    2010-07-01

    ... the source. The level is not fixed and can change as the emissions from each emission point change or...) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants From Petroleum Refineries § 63.642 General standards....

  16. 40 CFR 63.862 - Standards.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Standards. 63.862 Section 63.862... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Chemical Recovery Combustion Sources at Kraft, Soda, Sulfite,...

  17. Air Risk Information Support Center

    Energy Technology Data Exchange (ETDEWEB)

    Shoaf, C.R.; Guth, D.J. [Environmental Protection Agency, Washington, DC (United States)

    1990-12-31

    The Air Risk Information Support Center (Air RISC) was initiated in early 1988 by the US Environmental Protection Agency`s (EPA) Office of Health and Environmental Assessment (OHEA) and the Office of Air Quality Planning and Standards (OAQPS) as a technology transfer effort that would focus on providing information to state and local environmental agencies and to EPA Regional Offices in the areas of health, risk, and exposure assessment for toxic air pollutants. Technical information is fostered and disseminated by Air RISCs three primary activities: (1) a {open_quotes}hotline{close_quotes}, (2) quick turn-around technical assistance projects, and (3) general technical guidance projects. 1 ref., 2 figs.

  18. Primary Research on the Standard System of Air Vehicle Calibration Models Used in Wind Tunnel Test%飞行器风洞试验标模体系研究初探

    Institute of Scientific and Technical Information of China (English)

    战培国; 罗月培

    2011-01-01

    风洞试验标模是一种评估风洞试验准度和验证CFD算法的通用校准模型.本文归纳分析了北大西洋公约组织AGARD系列、法国ONERAM系列为代表的国外风洞试验标模发展情况,阐述了我国DBM、GBM、HSCM风洞标模系列的发展现状,探讨了建立和完善风洞试验标模体系的一些问题,意在为国内风洞和试验技术发展提供参考.%The standard air vehicle calibration model is a common calibration model used for evaluating wind tunnel test results and validating CFD methods.This paper analyses the development of overseas wind tunnel calibration models,typically,NATO AGARD series and ONERA M series in France,introduces state of the art domestic calibration models,such as DBM,CBM and HSCM series,discusses some problems about setting up and consummating the system of calibration models.The purpose is to provide thoughts and references for the development of domestic wind tunnel techniques.

  19. Air pollutant and greenhouse gas emissions of passenger cars. A comparison of standard-based values and practical data per fuel type; Luchtvervuilende en klimaatemissies van personenauto's. Een vergelijking van norm- en praktijkwaarden per brandstofsoort

    Energy Technology Data Exchange (ETDEWEB)

    Van Essen, H.P.; Van Grinsven, A.H.; Hoen, M.J.J. ' t

    2013-10-15

    Although tax regulations provide an incentive for buying a car with reduced CO2 emissions, in the coming years the share of diesel vehicles in the business segment is likely to grow, thus unintentionally threatening air quality. This is because the NOx emissions of a modern Euro 5 diesel car are still very high in practice. Despite the NOx Euro standards for diesel vehicles having been substantially tightened since 1992, in practice there proves to have been very little progress, with Euro 5 diesel vehicles still emitting approximately the same amount of NOx as 21 years ago, as the present study shows [Dutch] De fiscale regels stimuleren de verkoop van auto's die minder CO2 uitstoten, maar zorgen de komende jaren naar verwachting voor een groei van het aandeel dieselauto's in het zakelijke segment. Deze groei vormt onbedoeld een bedreiging voor de luchtkwaliteit. Dit komt doordat de luchtvervuilende NOx-emissie van een moderne Euro 5-dieselauto's in de praktijk nog altijd erg hoog is. Ondanks dat de NOx-Euronormen voor diesels sinds 1992 flink zijn aangescherpt, blijkt in de praktijk dat er nauwelijks progressie is geboekt en dat een Euro 5-diesel nog steeds gemiddeld evenveel NOx-uitstoot als 21 jaar geleden.

  20. Canada's Clean Air Act

    International Nuclear Information System (INIS)

    This paper provided an outline of Canada's Clean Air Act and examined some of the regulatory changes that will occur as a result of its implementation. The Act is being introduced to strengthen the legislative basis for taking action on reducing air pollution and GHGs, and will allow the government to regulate both indoor and outdoor air pollutants and GHGs. The Act will require the Ministers of the Environment and Health to establish national air quality objectives, as well as to monitor and report on their attainment. The Canadian Environmental Protection Act will be amended to enable the government to regulate the blending of fuels and their components. The Motor Vehicle Fuel Consumption Standards Act will also be amended to enhance the government's authority to regulate vehicle fuel efficiency. The Energy Efficiency Act will also be expanded to allow the government to set energy efficiency standards and labelling requirements for a wider range of consumer and commercial products. The Act will commit to short, medium and long-term industrial air pollution targets. Regulations will be proposed for emissions from industry; on-road and off-road vehicles and engines; and consumer and commercial products. It was concluded that the Government of Canada will continue to consult with provinces, territories, industries and Canadians to set and reach targets for the reduction of both indoor and outdoor air pollutants and GHG emissions. 6 figs

  1. A practical implementation of the 2010 IPEM high dose rate brachytherapy code of practice for the calibration of {sup 192}Ir sources

    Energy Technology Data Exchange (ETDEWEB)

    Awunor, O A; Lecomber, A R; Richmond, N; Walker, C, E-mail: Onuora.Awunor@stees.nhs.uk [Regional Medical Physics Department, James Cook University Hospital, Marton Road, Middlesbrough, TS4 3BW (United Kingdom)

    2011-08-21

    This paper details a practical method for deriving the reference air kerma rate calibration coefficient for Farmer NE2571 chambers using the UK Institute of Physics and Engineering in Medicine (IPEM) code of practice for the determination of the reference air kerma rate for HDR {sup 192}Ir brachytherapy sources based on the National Physical Laboratory (NPL) air kerma standard. The reference air kerma rate calibration coefficient was derived using pressure, temperature and source decay corrected ionization chamber response measurements over three successive {sup 192}Ir source clinical cycles. A secondary standard instrument (a Standard Imaging 1000 Plus well chamber) and four tertiary standard instruments (one additional Standard Imaging 1000 Plus well chamber and three Farmer NE2571 chambers housed in a perspex phantom) were used to provide traceability to the NPL primary standard and enable comparison of performance between the chambers. Conservative and optimized estimates on the expanded uncertainties (k = 2) associated with chamber response, ion recombination and reference air kerma rate calibration coefficient were determined. This was seen to be 2.3% and 0.4% respectively for chamber response, 0.2% and 0.08% respectively for ion recombination and 2.6% and 1.2% respectively for the calibration coefficient. No significant change in ion recombination with source decay was observed over the duration of clinical use of the respective {sup 192}Ir sources.

  2. 78 FR 19990 - Approval and Promulgation of Air Quality Implementation Plans; Ohio; Ohio Ambient Air Quality...

    Science.gov (United States)

    2013-04-03

    ... the relocated air quality standard rules. This action was published at 75 FR 65572 as a direct final... AGENCY 40 CFR Part 52 Approval and Promulgation of Air Quality Implementation Plans; Ohio; Ohio Ambient Air Quality Standards; Correction AGENCY: Environmental Protection Agency (EPA). ACTION: Final...

  3. 75 FR 65572 - Approval and Promulgation of Air Quality Implementation Plans; Ohio; Ohio Ambient Air Quality...

    Science.gov (United States)

    2010-10-26

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of Air Quality Implementation Plans; Ohio; Ohio Ambient Air Quality Standards AGENCY: Environmental Protection Agency (EPA). ACTION: Direct final rule... of Ohio's Ambient Air Quality Standards (AAQS) into Ohio's State Implementation Plan (SIP) under...

  4. 78 FR 63878 - Approval and Promulgation of Air Quality Implementation Plans; Virginia; Revised Ambient Air...

    Science.gov (United States)

    2013-10-25

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of Air Quality Implementation Plans; Virginia; Revised Ambient Air Quality Standards for Fine Particulate Matter AGENCY: Environmental Protection Agency (EPA... Commonwealth of Virginia State Implementation Plan (SIP). The revisions add ambient air quality standards...

  5. 78 FR 23492 - Approval and Promulgation of Air Quality Implementation Plans; Indiana; Particulate Matter Air...

    Science.gov (United States)

    2013-04-19

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of Air Quality Implementation Plans; Indiana; Particulate Matter Air Quality Standards AGENCY: Environmental Protection Agency (EPA). ACTION: Direct final rule... Ambient Air Quality Standards (NAAQS) promulgated by EPA in 2006, and removes the annual coarse...

  6. Radioactive air sampling methods

    CERN Document Server

    Maiello, Mark L

    2010-01-01

    Although the field of radioactive air sampling has matured and evolved over decades, it has lacked a single resource that assimilates technical and background information on its many facets. Edited by experts and with contributions from top practitioners and researchers, Radioactive Air Sampling Methods provides authoritative guidance on measuring airborne radioactivity from industrial, research, and nuclear power operations, as well as naturally occuring radioactivity in the environment. Designed for industrial hygienists, air quality experts, and heath physicists, the book delves into the applied research advancing and transforming practice with improvements to measurement equipment, human dose modeling of inhaled radioactivity, and radiation safety regulations. To present a wide picture of the field, it covers the international and national standards that guide the quality of air sampling measurements and equipment. It discusses emergency response issues, including radioactive fallout and the assets used ...

  7. 77 FR 12524 - Approval and Promulgation of Air Quality Implementation Plans; Indiana; Lead Ambient Air Quality...

    Science.gov (United States)

    2012-03-01

    ... AGENCY 40 CFR Part 52 Approval and Promulgation of Air Quality Implementation Plans; Indiana; Lead Ambient Air Quality Standards AGENCY: Environmental Protection Agency (EPA). ACTION: Proposed rule...) under the Clean Air Act (CAA). This submittal incorporates the National Ambient Air Quality...

  8. 78 FR 9593 - Approval and Promulgation of Air Quality Implementation Plans; Maryland; Amendments to Maryland's...

    Science.gov (United States)

    2013-02-11

    ..., Air pollution control, Carbon monoxide, Incorporation by reference, Intergovernmental relations, Lead... to Maryland's Ambient Air Quality Standards AGENCY: Environmental Protection Agency (EPA). ACTION... reference of the national ambient air quality standards (NAAQS) by the State of Maryland. EPA is...

  9. 40 CFR Table 7 to Subpart Hhhhh of... - Partially Soluble Hazardous Air Pollutants

    Science.gov (United States)

    2010-07-01

    ... Pollutants 7 Table 7 to Subpart HHHHH of Part 63 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Miscellaneous...

  10. 40 CFR Table 8 to Subpart Ffff of... - Partially Soluble Hazardous Air Pollutants

    Science.gov (United States)

    2010-07-01

    ... Pollutants 8 Table 8 to Subpart FFFF of Part 63 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES National Emission Standards for Hazardous Air Pollutants: Miscellaneous Organic...

  11. 76 FR 30604 - Approval of the Clean Air Act, Section 112(l), Authority for Hazardous Air Pollutants...

    Science.gov (United States)

    2011-05-26

    ... AGENCY 40 CFR Part 63 Approval of the Clean Air Act, Section 112(l), Authority for Hazardous Air Pollutants: Perchloroethylene Air Emission Standards for Dry Cleaning Facilities: State of Maine Department... substitution for the amended National Emissions Standards for Hazardous Air Pollutants for...

  12. 75 FR 65594 - Approval and Promulgation of Air Quality Implementation Plans; Ohio; Ohio Ambient Air Quality...

    Science.gov (United States)

    2010-10-26

    .... Hand Delivery: Jay Bortzer, Chief, Air Programs Branch (AR-18J), U.S. Environmental Protection Agency... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION... Air Quality Standards AGENCY: Environmental Protection Agency (EPA). ACTION: Proposed rule....

  13. 40 CFR 63.60 - Deletion of caprolactam from the list of hazardous air pollutants.

    Science.gov (United States)

    2010-07-01

    ... of hazardous air pollutants. 63.60 Section 63.60 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES List of Hazardous Air Pollutants, Petitions Process, Lesser Quantity...

  14. 30 CFR 57.13010 - Reciprocating-type air compressors.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Reciprocating-type air compressors. 57.13010... Air and Boilers § 57.13010 Reciprocating-type air compressors. (a) Reciprocating-type air compressors... than 25 percent. (b) However, this standard does not apply to reciprocating-type air compressors...

  15. Performance testing and classification of air filters and particulate air filters. Leistungspruefung und Klassifikation von Luft- und Schwebstoffiltern

    Energy Technology Data Exchange (ETDEWEB)

    Lorenz, W.

    1991-09-01

    Standarized rest methods are available for evaluation of the performance of air filters and particulate air filters. While air filters are tested applying the internationally accepted ASHRAE method, standard particulate air filters, or HEPA filters (high-efficiency particulate air), may be tested and classified based on different standards. The methods applied, however, are insufficiently accurate with ragard to high-performance particulate air filters, or ULPA filters (ultralow penetration air). Improved, European-standard test methods are currently being developed. The CEN/TC 195 committee is responsible for the European standardization of air filters and particulate air filters. Details are given about the present situation of air and particulate air filter performance testing and classification. (orig.).

  16. Calibration of survey meters at the Algerian Secondary Standard Dosimetry Laboratory

    International Nuclear Information System (INIS)

    Full text: The Algerian Secondary Standard Dosimetry Laboratory, which became a Regional AFRA Designated Centre for French spoken countries, in the field of calibration since 2005, has developed and implemented methodologies for the calibration of radiation protection instruments such as survey meters. These instruments were initially calibrated in terms of air kerma free in air (NK) in 60Co, 137Cs gamma radiations. Although the recommended calibration quantity is H*(10) (Sv/h), most of instruments measure different physical quantities and problems about the expression of calibration factor in the calibration certificates are always raised. In order to switch to calibrations in terms of H*(10), a feasibility study was performed using instruments submitted for calibration at the SSDL. This paper presents the variation of the calibration coefficients, Fc, obtained since 2005 for three types of survey meters. The uncertainty components involved in the determination of Fc are analysed in details. Material and method: This study included the most used survey meters in Algeria and received at the SSDL in 2005 and 2006 which consist of 127 survey-meters of type Automess (different models), 80 Ludlum model 3 and 23 Graetz X 5 DE. Calibrations were performed using the beam output decay method. This output was determined with the Reference Standard chamber of type NE 2575 in 2005 and LS01 in 2006, both calibrated at the IAEA calibration laboratory. The average calibration coefficients, Fc, which converts the instruments reading to ambient equivalent absorbed dose, are calculated and the relative standard deviations assessed. The variation of calibration coefficients, for each type of instruments, is compared to the overall stated uncertainty for this coefficient. Results and discussion: The mean calibration coefficients in terms of H*(10) were lying from 0.993 ± 2.55% and 1.039 ± 3.16% for the Automess survey meters and from . The results are 1.215 ± 5.93%, 1.149 ± 14

  17. Strong interactions in air showers

    Energy Technology Data Exchange (ETDEWEB)

    Dietrich, Dennis D. [Arnold Sommerfeld Center, Ludwig-Maximilians-Universität, Theresienstraße, München (Germany); Institut für Theoretische Physik, Goethe-Universität, Max-von-Laue-Straße, Frankfurt am Main (Germany)

    2015-03-02

    We study the role new gauge interactions in extensions of the standard model play in air showers initiated by ultrahigh-energy cosmic rays. Hadron-hadron events remain dominated by quantum chromodynamics, while projectiles and/or targets from beyond the standard model permit us to see qualitative differences arising due to the new interactions.

  18. ['Gold standard', not 'golden standard'

    NARCIS (Netherlands)

    Claassen, J.A.H.R.

    2005-01-01

    In medical literature, both 'gold standard' and 'golden standard' are employed to describe a reference test used for comparison with a novel method. The term 'gold standard' in its current sense in medical research was coined by Rudd in 1979, in reference to the monetary gold standard. In the same w

  19. 40 CFR 61.32 - Emission standard.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Emission standard. 61.32 Section 61.32... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Beryllium § 61.32 Emission standard. (a) Emissions to the atmosphere from stationary sources subject to the provisions of this...

  20. 40 CFR 63.112 - Emission standard.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Emission standard. 63.112 Section 63...) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES National Emission Standards... Process Vents, Storage Vessels, Transfer Operations, and Wastewater § 63.112 Emission standard. (a)...

  1. 40 CFR 61.42 - Emission standard.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Emission standard. 61.42 Section 61.42... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Beryllium Rocket Motor Firing § 61.42 Emission standard. (a) Emissions to the atmosphere from rocket-motor test sites shall...

  2. 40 CFR 61.52 - Emission standard.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Emission standard. 61.52 Section 61.52... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Mercury § 61.52 Emission standard. (a) Emissions to the atmosphere from mercury ore processing facilities and mercury cell...

  3. 40 CFR 61.112 - Standards.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Standards. 61.112 Section 61.112... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Equipment Leaks (Fugitive Emission Sources) of Benzene § 61.112 Standards. (a) Each owner or operator subject to the provisions...

  4. 40 CFR 63.362 - Standards.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Standards. 63.362 Section 63.362... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES Ethylene Oxide Emissions Standards for Sterilization Facilities § 63.362 Standards. (a) Each owner or operator of a source subject to...

  5. 40 CFR 63.562 - Standards.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Standards. 63.562 Section 63.562... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES National Emission Standards for Marine Tank Vessel Loading Operations § 63.562 Standards. (a) The emissions limitations in paragraphs...

  6. 40 CFR 63.342 - Standards.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Standards. 63.342 Section 63.342... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES National Emission Standards for... Standards. (a) Each owner or operator of an affected source subject to the provisions of this subpart...

  7. 40 CFR 63.962 - Standards.

    Science.gov (United States)

    2010-07-01

    ....693 in 40 CFR part 63, subpart DD—National Emission Standards for Hazardous Air Pollutant Standards... in accordance with the standards specified in 40 CFR 63.693. ... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Standards. 63.962 Section...

  8. 40 CFR 61.92 - Standard.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Standard. 61.92 Section 61.92... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standards for Emissions of Radionuclides Other Than Radon From Department of Energy Facilities § 61.92 Standard. Emissions of radionuclides...

  9. 40 CFR 61.192 - Standard.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Standard. 61.192 Section 61.192... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standards for Radon Emissions From Department of Energy Facilities § 61.192 Standard. No source at a Department of Energy facility shall...

  10. 40 CFR 61.202 - Standard.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Standard. 61.202 Section 61.202... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standards for Radon Emissions From Phosphogypsum Stacks § 61.202 Standard. Each person who generates phosphogypsum shall place all phosphogypsum...

  11. Representativeness of air quality monitoring networks

    NARCIS (Netherlands)

    Duyzer, J.; Hout, D. van den; Zandveld, P.; Ratingen, S. van

    2015-01-01

    The suitability of European networks to check compliance with air quality standards and to assess exposure of the population was investigated. An air quality model (URBIS) was applied to estimate and compare the spatial distribution of the concentration of nitrogen dioxide (NO2) in ambient air in fo

  12. Air ions and aerosol science

    Science.gov (United States)

    Tammet, Hannes

    1996-03-01

    Collaboration between Gas Discharge and Plasma Physics, Atmospheric Electricity, and Aerosol Science is a factor of success in the research of air ions. The concept of air ion as of any carrier of electrical current through the air is inherent to Atmospheric Electricity under which a considerable statistical information about the air ion mobility spectrum is collected. A new model of air ion size-mobility correlation has been developed proceeding from Aerosol Science and joining the methods of neighboring research fields. The predicted temperature variation of the mobility disagrees with the commonly used Langevin rule for the reduction of air ion mobilities to the standard conditions. Concurrent errors are too big to be neglected in applications. The critical diameter distinguishing cluster ions and charged aerosol particles has been estimated to be 1.4-1.8 nm.

  13. Air ions and aerosol science

    Energy Technology Data Exchange (ETDEWEB)

    Tammet, H. [Department of Environmental Physics, Tartu University, Tartu, Estonia (Estonia) 2400

    1996-03-01

    Collaboration between Gas Discharge and Plasma Physics, Atmospheric Electricity, and Aerosol Science is a factor of success in the research of air ions. The concept of air ion as of any carrier of electrical current through the air is inherent to Atmospheric Electricity under which a considerable statistical information about the air ion mobility spectrum is collected. A new model of air ion size-mobility correlation has been developed proceeding from Aerosol Science and joining the methods of neighboring research fields. The predicted temperature variation of the mobility disagrees with the commonly used Langevin rule for the reduction of air ion mobilities to the standard conditions. Concurrent errors are too big to be neglected in applications. The critical diameter distinguishing cluster ions and charged aerosol particles has been estimated to be 1.4{endash}1.8 nm. {copyright} {ital 1996 American Institute of Physics.}

  14. Thin air

    OpenAIRE

    Jasanoff, Sheila

    2013-01-01

    Clearing the air How do we grasp the air? Without Michel Callon’s guidance, I might never have asked that question. Years ago, when I first entered environmental law practice, I took it for granted that problems such as air pollution exist “out there” in the real world for science to discover and law to fix. It is a measure of Callon’s influence that I understand the law today as a metaphysical instrument, no less powerful in its capacity to order nature than the tools of the ancient oracular...

  15. Accounting standards

    NARCIS (Netherlands)

    B. Stellinga

    2014-01-01

    The European and global regulation of accounting standards have witnessed remarkable changes over the past twenty years. In the early 1990s, EU accounting practices were fragmented along national lines and US accounting standards were the de facto global standards. Since 2005, all EU listed companie

  16. Analysis on the Standard Conformance of Thermal Circuit Breaker of Heat-pump Water Heater and Air-conditioner%关于热泵热水器和空调热断路器结构标准符合性浅析

    Institute of Scientific and Technical Information of China (English)

    马洁丹; 肖凯佳

    2015-01-01

    This paper analyzes the standard conformance of the construction of thermal circuit breaker in air-condi-tioner and heat pump and some designs according to the standards of IEC 60335 series. Besides, it provides responding suggestions to the designers.%本文根据标准IEC 60335系列,对带电辅热的空调及热泵的热断路器及部分设计方案进行标准符合性分析,给出相应的意见,以供设计人员参考.

  17. [Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio]. Volume 3, Appendix A, Draft standard operating procedures and elements: Sampling and Analysis Plan (SAP): Phase 1, Task 4, Field Investigation, Draft

    Energy Technology Data Exchange (ETDEWEB)

    1991-10-01

    This report presents information concerning field procedures employed during the monitoring, well construction, well purging, sampling, and well logging at the Wright-Patterson Air Force Base. Activities were conducted in an effort to evaluate ground water contamination.

  18. Air Pollution

    Science.gov (United States)

    ... to a close in June 2013 when the company, Conscious Clothing, was awarded the My Air grand ... Page Options: Request Translation Services Facebook Twitter LinkedIn Google+ Reddit Email Evernote More Increase Font Size Decrease ...

  19. Study of the Influence of Scattered Radiation at a Gamma Irradiator

    International Nuclear Information System (INIS)

    The Calibration Laboratory of IPEN offers calibration services for portable radiation monitors using a Buchler gamma irradiator with 137Cs and 60Co radioactive sources. The beam dosimetry measurements are taken periodically between the source-instrument distances of 1 m and 4 m. The ISO 4037 standard (International Organization for Standardization) states that the air kerma rate due to scattered radiation shall not exceed 5% of that due to direct radiation. To verify if the facility was in accordance to the requirements, the evaluation of the scattered radiation was performed in this work. The air kerma rates were measured on the beam axis at various distances from the source up to 5.5 m, and the radiation attenuation curve was obtained. The air kerma rates were proportional within 5% of deviation to the inverse square law from the source centre to the detector centre, as required by the ISO 4037 standard. (authors)

  20. Determination of conversion factors of kerma and fluence to ambient dose equivalent for X-rays generated between 50 kVp to 125 kVp

    International Nuclear Information System (INIS)

    The ambient dose equivalent was determined experimentally on the interval of energy of X ray applied in diagnostic radiology. A PMMA sphere was used to simulate the trunk human (phantom), based on the definition of the report ICRU 39. The absorbed dose in different positions in the phantom was determined using LiF-TLD 100. The X ray spectra were measured with a high-purity germanium detector (HP Ge). It was also determined the HVL and the effective energy in this energy range. The conversion coefficient of the Kair and Φ to H*(d) were determined to 10, 50 and 60 mm deep in the PMMA sphere. The obtained values were compared with data of the literature. The maximum uncertainty obtained for the coefficients was 7.2%. All parameters were also determined to the X ray quality of the incident and transmitted beam by the patient, according to the recommendation of the standard DIN 6872. The conversion factor was calculated for those situations where the X-ray beam is transmitted by a layer and Pb and it is necessary to estimate the effective dose, as in the case of shielding project of radiology diagnosis room. (author)

  1. Communications standards

    CERN Document Server

    Stokes, A V

    1986-01-01

    Communications Standards deals with the standardization of computer communication networks. This book examines the types of local area networks (LANs) that have been developed and looks at some of the relevant protocols in more detail. The work of Project 802 is briefly discussed, along with a protocol which has developed from one of the LAN standards and is now a de facto standard in one particular area, namely the Manufacturing Automation Protocol (MAP). Factors that affect the usage of networks, such as network management and security, are also considered. This book is divided into three se

  2. Achieving Standardization

    DEFF Research Database (Denmark)

    Henningsson, Stefan

    2016-01-01

    competitive, national customs and regional economic organizations are seeking to establish a standardized solution for digital reporting of customs data. However, standardization has proven hard to achieve in the socio-technical e-Customs solution. In this chapter, the authors identify and describe what has...... to be harmonized in order for a global company to perceive e-Customs as standardized. In doing so, they contribute an explanation of the challenges associated with using a standardization mechanism for harmonizing socio-technical information systems....

  3. Achieving Standardization

    DEFF Research Database (Denmark)

    Henningsson, Stefan

    2014-01-01

    competitive, national customs and regional economic organizations are seeking to establish a standardized solution for digital reporting of customs data. However, standardization has proven hard to achieve in the socio-technical e-Customs solution. In this chapter, the authors identify and describe what has...... to be harmonized in order for a global company to perceive e-Customs as standardized. In doing so, they contribute an explanation of the challenges associated with using a standardization mechanism for harmonizing socio-technical information systems....

  4. Residential Forced Air System Cabinet Leakage and Blower Performance

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Iain S.; Dickerhoff, Darryl J.; Delp, William W.

    2010-03-01

    This project evaluated the air leakage and electric power consumption of Residential HVAC components, with a particular focus on air leakage of furnace cabinets. Laboratory testing of HVAC components indicated that air leakage can be significant and highly variable from unit to unit ? indicating the need for a standard test method and specifying maximum allowable air leakage in California State energy codes. To further this effort, this project provided technical assistance for the development of a national standard for Residential HVAC equipment air leakage. This standard is being developed by ASHRAE and is called"ASHRAE Standard 193P - Method of test for Determining the Air Leakage Rate of HVAC Equipment". The final part of this project evaluated techniques for measurement of furnace blower power consumption. A draft test procedure for power consumption was developed in collaboration with the Canadian General Standards Board: CSA 823"Performance Standard for air handlers in residential space conditioning systems".

  5. [Air quality control systems: heating, ventilating, and air conditioning (HVAC)].

    Science.gov (United States)

    Bellucci Sessa, R; Riccio, G

    2004-01-01

    After a brief illustration of the principal layout schemes of Heating, Ventilating, and Air Conditioning (HVAC), the first part of this paper summarizes the standards, both voluntary and compulsory, regulating HVAC facilities design and installation with regard to the question of Indoor Air Quality (IAQ). The paper then examines the problem of ventilation systems maintenance and the essential hygienistic requirements in whose absence HVAC facilities may become a risk factor for people working or living in the building. Lastly, the paper deals with HVAC design strategies and methods, which aim not only to satisfy comfort and air quality requirements, but also to ensure easy and effective maintenance procedures.

  6. Air surveillance

    Energy Technology Data Exchange (ETDEWEB)

    Patton, G.W.

    1995-06-01

    This section of the 1994 Hanford Site Environmental Report summarizes the air surveillance and monitoring programs currently in operation at that Hanford Site. Atmospheric releases of pollutants from Hanford to the surrounding region are a potential source of human exposure. For that reason, both radioactive and nonradioactive materials in air are monitored at a number of locations. The influence of Hanford emissions on local radionuclide concentrations was evaluated by comparing concentrations measured at distant locations within the region to concentrations measured at the Site perimeter. This section discusses sample collection, analytical methods, and the results of the Hanford air surveillance program. A complete listing of all analytical results summarized in this section is reported separately by Bisping (1995).

  7. Air Cleaning at the USAEC Y-12 Plant

    International Nuclear Information System (INIS)

    This paper describes some of the air-cleaning requirements of production, research, development and biological facilities in the Y-12 area. Problems and their solutions in hazardous-material containment, air cleaning, contamination control, and air pollution control are enumerated. Bioclean and laminar-flow clean rooms, germ-free supply air systems, exhaust systems for handling toxic and radioactive materials, virus containment and exhaust facilities are described. The Plant's practices regarding air cleaning are discussed including standardization of specifications for high-efficiency particulate air filters and mounting frames, DOP testing of air filter systems, and the replacement of sub-standard filter installations. (author)

  8. 77 FR 65310 - Additional Air Quality Designations for the 2006 24-Hour Fine Particle National Ambient Air...

    Science.gov (United States)

    2012-10-26

    ... the 2006 24-hour Fine Particle (PM 2.5 ) National Ambient Air Quality Standards,'' 74 FR 58688... AGENCY 40 CFR Part 81 Additional Air Quality Designations for the 2006 24-Hour Fine Particle National Ambient Air Quality Standards AGENCY: Environmental Protection Agency (EPA). ACTION:...

  9. Training Standardization

    International Nuclear Information System (INIS)

    The article describes the benefits of and required process and recommendations for implementing the standardization of training in the nuclear power industry in the United States and abroad. Current Information and Communication Technologies (ICT) enable training standardization in the nuclear power industry. The delivery of training through the Internet, Intranet and video over IP will facilitate this standardization and bring multiple benefits to the nuclear power industry worldwide. As the amount of available qualified and experienced professionals decreases because of retirements and fewer nuclear engineering institutions, standardized training will help increase the number of available professionals in the industry. Technology will make it possible to use the experience of retired professionals who may be interested in working part-time from a remote location. Well-planned standardized training will prevent a fragmented approach among utilities, and it will save the industry considerable resources in the long run. It will also ensure cost-effective and safe nuclear power plant operation

  10. Progress in the prevention and control of air pollution in 1988: Report to congress. Annual report

    International Nuclear Information System (INIS)

    Contents of this study: air quality trends, monitoring, and modeling; air pollution research programs; development of national ambient air; quality standards; assessment and control of toxic air pollutants; status of air quality management programs; control of stationary source emissions; stationary source compliance; control of mobile source emissions; stratospheric ozone protection; indoor air quality; acid deposition; radon assessment and remediation; litigation

  11. Healthy Air Outdoors

    Science.gov (United States)

    ... lung.org > Our Initiatives > Healthy Air > Outdoor Healthy Air Outdoors The quality of the air we breathe ... families and can even shorten their lives. Outdoor Air Pollution and Health Outdoor air pollution continues to ...

  12. 30 CFR 56.13010 - Reciprocating-type air compressors.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Reciprocating-type air compressors. 56.13010... and Boilers § 56.13010 Reciprocating-type air compressors. (a) Reciprocating-type air compressors... than 25 percent. (b) However, this standard does not apply to reciprocating-type air compressors...

  13. Practical Hydrogen Loading of Air Silica Fibres

    DEFF Research Database (Denmark)

    Sørensen, Henrik Rokkjær; Jensen, Jesper Bevensee; Jensen, Jesper Bo Damm;

    2005-01-01

    A method for hydrogen-loading air-silica optical fibres has been developed allowing out-diffusion times comparable to standard step-index fibres. Examples of the first grating written in Ge-doped air-silica fibres using a 266nm UV-laser are shown.......A method for hydrogen-loading air-silica optical fibres has been developed allowing out-diffusion times comparable to standard step-index fibres. Examples of the first grating written in Ge-doped air-silica fibres using a 266nm UV-laser are shown....

  14. 40 CFR 61.271 - Emission standard.

    Science.gov (United States)

    2010-07-01

    ... device requirements of 40 CFR 60.18. (3) The specifications and requirements listed in paragraphs (c)(1... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Emission standard. 61.271 Section 61...) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Benzene...

  15. 40 CFR 60.612 - Standards.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standards. 60.612 Section 60.612 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Volatile Organic Compound (VOC)...

  16. 40 CFR 60.632 - Standards.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standards. 60.632 Section 60.632 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Equipment Leaks of VOC From...

  17. 40 CFR 60.702 - Standards.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standards. 60.702 Section 60.702 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Volatile Organic Compound Emissions...

  18. 40 CFR 60.592a - Standards.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standards. 60.592a Section 60.592a Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Equipment Leaks of VOC in...

  19. 40 CFR 60.662 - Standards.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standards. 60.662 Section 60.662 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Volatile Organic Compound (VOC)...

  20. 机房专用空调风冷冷凝器高热密度与噪声超标治理工程简论%Management of Air-cooled Condenser Heat Density and Noise Exceeding the Standard

    Institute of Scientific and Technical Information of China (English)

    黄宇慧; 董陈卫

    2013-01-01

      针对某风冷型机房专用空调存在着夏季运行时频繁出现高压报警、空调停机故障及室外风冷冷凝器运行时产生噪声超标等问题,开创性地采用了双冷凝器(水冷+风冷)制冷系统治理方案。该方案不仅彻底解决了以上2个问题,还提高了机房专用空调机组的运行效率及可靠性。%Air-conditioners appear high pressure alarm frequently in summer, and the operating noise of air-cooled condensers exceeds the standard. It presents the scheme of double condenser( water cooling and air cooling system control program). The scheme can not only solve the above two problems, but also can improve the room air-conditioner unit operation efficiency and reliability.

  1. EOS standards

    Energy Technology Data Exchange (ETDEWEB)

    Greeff, Carl W [Los Alamos National Laboratory

    2011-01-12

    An approach to creating accurate EOS for pressure standards is described. Applications to Cu, Au, and Ta are shown. Extension of the method to high compressions using DFT is illustrated. Comparisons with modern functionals show promise.

  2. (Terminology standardization)

    Energy Technology Data Exchange (ETDEWEB)

    Strehlow, R.A.

    1990-10-19

    Terminological requirements in information management was but one of the principal themes of the 2nd Congress on Terminology and Knowledge Engineering. The traveler represented the American Society for Testing and Materials' Committee on Terminology, of which he is the Chair. The traveler's invited workshop emphasized terminology standardization requirements in databases of material properties as well as practical terminology standardizing methods. The congress included six workshops in addition to approximately 82 lectures and papers from terminologists, artificial intelligence practitioners, and subject specialists from 18 countries. There were approximately 292 registrants from 33 countries who participated in the congress. The congress topics were broad. Examples were the increasing use of International Standards Organization (ISO) Standards in legislated systems such as the USSR Automated Data Bank of Standardized Terminology, the enhanced Physics Training Program based on terminology standardization in Physics in the Chinese province of Inner Mongolia, and the technical concept dictionary being developed at the Japan Electronic Dictionary Research Institute, which is considered to be the key to advanced artificial intelligence applications. The more usual roles of terminology work in the areas of machine translation. indexing protocols, knowledge theory, and data transfer in several subject specialties were also addressed, along with numerous special language terminology areas.

  3. Royal Danish Air Force. Air Operations Doctrine

    DEFF Research Database (Denmark)

    Nørby, Søren

    This brief examines the development of the first Danish Air Force Air Operations Doctrine, which was officially commissioned in October 1997 and remained in effect until 2010. The development of a Danish air power doctrine was heavily influenced by the work of Colonel John Warden (USAF), both...... through his book ”The Air Campaign” and his subsequent planning of the air campaign against Iraq in 1990-1991. Warden’s ideas came to Denmark and the Danish Air Force by way of Danish Air Force students attending the United States Air Force Air University in Alabama, USA. Back in Denmark, graduates from...... the Air University inspired a small number of passionate airmen, who then wrote the Danish Air Operations Doctrine. The process was supported by the Air Force Tactical Command, which found that the work dovetailed perfectly with the transformation process that the Danish Air Force was in the midst...

  4. Guidance for air sampling at nuclear facilities

    International Nuclear Information System (INIS)

    The principal uses of air sampling at nuclear facilities are to monitor general levels of radioactive air contamination, identify sources of air contamination, and evaluate the effectiveness of contaminant control equipment, determine exposures of individual workers, and provide automatic warning of hazardous concentrations of radioactivity. These applications of air sampling are discussed with respect to standards of occupational exposure, instrumentation, sample analysis, sampling protocol, and statistical treatment of concentration data. Emphasis is given to the influence of spacial and temporal variations of radionuclide concentration on the location, duration, and frequency of air sampling

  5. Good air quality in offices improves productivity

    DEFF Research Database (Denmark)

    Fanger, Povl Ole

    2000-01-01

    Three recent independent studies have documented that the quality of indoor air has a significant and positive influence on the productivity of office workers. A combined analysis of the results of the three studies shows a significant relationship between productivity and perceived indoor air...... quality. The impact on productivity justifies a much higher indoor air quality than the minimum levels prescribed in present standards and guidelines. One way of providing air of high quality for people to breathe, without involving excessive ventilation rates and energy use, is to provide "personalized...... air" to each individual. The application of this concept is discussed....

  6. Good air quality in offices improves productivity

    DEFF Research Database (Denmark)

    Fanger, Povl Ole

    2000-01-01

    Three recent independent studies have documented that the quality of indoor air has a significant and positive influence or? the productivity of office workers. A combined analysis of the results of the three studies shows a significant relationship between productivity and perceived indoor air...... quality. The impact on productivity justifies a much higher indoor air quality than the minimum levels prescribed in present standards and guidelines. One way of providing air of high quality for people to breathe, without involving excessive ventilation rates and energy use, is to provide "personalized...... air" to each individual. The application of this concept is discussed in this paper: (C) 2000 Journal of Mechanical Engineering. All rights reserved....

  7. Determination of conversion factors of kerma and fluence to ambient dose equivalent for X-rays generated between 50 kV{sub p} to 125 kV{sub p}; Determinacao dos fatores de conversao de kerma no ar e de fluencia para o equivalente de dose ambiental para raios-X gerados no intervalo de 50 kV{sub p} a 125 kV{sub p}

    Energy Technology Data Exchange (ETDEWEB)

    Nogueira, Maria do Socorro

    1997-12-31

    The ambient dose equivalent was determined experimentally on the interval of energy of X ray applied in diagnostic radiology. A PMMA sphere was used to simulate the trunk human (phantom), based on the definition of the report ICRU 39. The absorbed dose in different positions in the phantom was determined using LiF-TLD 100. The X ray spectra were measured with a high-purity germanium detector (HP Ge). It was also determined the HVL and the effective energy in this energy range. The conversion coefficient of the K{sub air} and {Phi} to H{sup *}(d) were determined to 10, 50 and 60 mm deep in the PMMA sphere. The obtained values were compared with data of the literature. The maximum uncertainty obtained for the coefficients was 7.2%. All parameters were also determined to the X ray quality of the incident and transmitted beam by the patient, according to the recommendation of the standard DIN 6872. The conversion factor was calculated for those situations where the X-ray beam is transmitted by a layer and Pb and it is necessary to estimate the effective dose, as in the case of shielding project of radiology diagnosis room. (author) 51 refs., 35 figs., 15 tabs.

  8. Beyond KERMA - neutron data for biomedical applications

    International Nuclear Information System (INIS)

    Presently, many new applications of fast neutrons are emerging or under development, like dose effects due to cosmic-ray neutrons for airplane crew, fast-neutron cancer therapy, studies of electronic failures induced by cosmic-ray neutrons, and accelerator-driven incineration of nuclear waste and energy production technologies. All these areas would benefit from improved neutron dosimetry. In this paper, the present rapid progress on measurements of double-differential neutron-induced nuclear reaction data are described. With such data at hand, the full response of, in principle, any system, including human tissue, can be calculated in detail. This could potentially revolutionise our understanding of biological effects in tissue due to fast neutrons. (author)

  9. Shaking hands on standards

    International Nuclear Information System (INIS)

    The buzz on the 1990 Amendments to the Clean Air Act grows louder as Phase 2, a 500-ppm valve-emissions limit, looms to within a few years. One question surrounding the legislation centers not so much on compliance as on the agreement between valve users and manufacturers on such topics as leak testing methods, measurement and documentation during valve manufacture. For chemical or oil companies, CAAA compliance can be facilitated with the assurance that equipment has been tested with industry-wide, uniform procedures. Under this premise, end users and manufacturers, as well as several industry organizations, are starting to devote effort to the problem of establishing a single standard

  10. Air filtration and indoor air quality

    DEFF Research Database (Denmark)

    Bekö, Gabriel

    2006-01-01

    Demands for better indoor air quality are increasing, since we spend most of our time indoors and we are more and more aware of indoor air pollution. Field studies in different parts of the world have documented that high percentage of occupants in many offices and buildings find the indoor air...... decent ventilation and air cleaning/air filtration, high indoor air quality cannot be accomplished. The need for effective air filtration has increased with increasing evidence on the hazardous effects of fine particles. Moreover, the air contains gaseous pollutants, removal of which requires various air...... cleaning techniques. Supply air filter is one of the key components in the ventilation system. Studies have shown that used ventilation filters themselves can be a significant source of indoor air pollution with consequent impact on perceived air quality, sick building syndrome symptoms and performance...

  11. Dosimetry standards

    International Nuclear Information System (INIS)

    The following leaflets are contained in this folder concerning the National Physical Laboratory's measurement services available in relation to dosimetry standards: Primary standards of X-ray exposure and X-ray irradiation facilities, X-ray dosimetry at therapy levels, Protection-level X-ray calibrations, Therapy-level gamma-ray facility, Fricke dosemeter reference service, Low-dose-rate gamma-ray facility, Penetrameter and kV meter calibration, Measurement services for radiation processing, Dichromate dosemeter reference service, Electron linear accelerator. (U.K.)

  12. Frequency standards

    CERN Document Server

    Riehle, Fritz

    2006-01-01

    Of all measurement units, frequency is the one that may be determined with the highest degree of accuracy. It equally allows precise measurements of other physical and technical quantities, whenever they can be measured in terms of frequency.This volume covers the central methods and techniques relevant for frequency standards developed in physics, electronics, quantum electronics, and statistics. After a review of the basic principles, the book looks at the realisation of commonly used components. It then continues with the description and characterisation of important frequency standards

  13. 75 FR 34647 - Approval of the Clean Air Act, Section 112(l), Authority for Hazardous Air Pollutants: Air...

    Science.gov (United States)

    2010-06-18

    .... See 64 FR 67793. Continuous web cleaning machines are solvent cleaning machines in which parts such as... Pollutants: Air Emission Standards for Halogenated Solvent Cleaning Machines: State of Rhode Island... Emissions from Organic Solvent Cleaning (``RI Regulation No. 36''), and the Rhode Island Air...

  14. 75 FR 59090 - Approval and Promulgation of Implementation Plans and Designation of Areas for Air Quality...

    Science.gov (United States)

    2010-09-27

    ... the Las Vegas Valley nonattainment area for the carbon monoxide national ambient air quality standard... protection, Air pollution control, Carbon monoxide, Incorporation by reference, Intergovernmental relations... for the Carbon Monoxide Standard AGENCY: Environmental Protection Agency (EPA). ACTION: Final...

  15. New Gasoline Standard in China

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ The Chinese government will reduce sulfur levels of lead-free gasoline to 150 parts per million (ppm) in the revised gas standard for the purpose to help improve air quality. The revised lead-free gas standard, to be announced by the end of this year, will drive gas with sulfur levels of 500 ppm out of market on Dec. 31,2009, said Li Xinmin, deputy director of the pollution control department of the State Environmental Protection Administration (SEPA), at a recent symposium on automobile pollution control. The new standard would meet the Euro-Ⅲ emission norm, which constrained sulfur levels to 150 ppm maximum.

  16. Technical support document: Energy efficiency standards for consumer products: Room air conditioners, water heaters, direct heating equipment, mobile home furnaces, kitchen ranges and ovens, pool heaters, fluorescent lamp ballasts and television sets. Volume 2, Fluorescent lamp ballasts, television sets, room air conditioners, and kitchen ranges and ovens

    Energy Technology Data Exchange (ETDEWEB)

    1993-11-01

    This document is divided into ``volumes`` B through E, dealing with individual classes of consumer products. Chapters in each present engineering analysis, base case forecasts, projected national impacts of standards, life-cycle costs and payback periods, impacts on manufacturers, impacts of standards on electric utilities, and environmental effects. Supporting appendices are included.

  17. 76 FR 59338 - Approval and Promulgation of Air Quality Implementation Plans; Montana; Revisions to the...

    Science.gov (United States)

    2011-09-26

    ... Part 52 Environmental protection, Air pollution control, Carbon monoxide, Intergovernmental relations... new rule will not interfere with compliance with the National Ambient Air Quality Standards (NAAQS) or... NAAQS, even within nonattainment areas. Since there are no ambient air quality standards for air...

  18. 40 CFR Table 1 to Subpart Eeee of... - Organic Hazardous Air Pollutants

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 12 2010-07-01 2010-07-01 true Organic Hazardous Air Pollutants 1...) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES National Emission Standards for Hazardous Air Pollutants: Organic Liquids Distribution...

  19. 40 CFR Table 8 to Subpart Ffff of... - Soluble Hazardous Air Pollutants

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 13 2010-07-01 2010-07-01 false Soluble Hazardous Air Pollutants 8...) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Miscellaneous...

  20. 40 CFR Table 9 to Subpart Ffff of... - Soluble Hazardous Air Pollutants

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 12 2010-07-01 2010-07-01 true Soluble Hazardous Air Pollutants 9...) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES National Emission Standards for Hazardous Air Pollutants: Miscellaneous Organic...

  1. 40 CFR Table 16 to Subpart Xxxx of... - Selected Hazardous Air Pollutants

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 12 2010-07-01 2010-07-01 true Selected Hazardous Air Pollutants 16...) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES National Emissions Standards for Hazardous Air Pollutants: Rubber Tire Manufacturing Pt. 63,...

  2. AirData

    Data.gov (United States)

    U.S. Environmental Protection Agency — The AirData site provides access to yearly summaries of United States air pollution data, taken from EPA's air pollution databases. AirData has information about...

  3. R9 Air Districts

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Region 9 Air Districts layer is a compilation of polygons representing the California Air Pollution Control and Air Quality Management Districts, Arizona Air...

  4. Hazardous Air Pollutants

    Science.gov (United States)

    ... Facebook Twitter Google+ Pinterest Contact Us Hazardous Air Pollutants Hazardous air pollutants are those known to cause ... protect against adverse environmental effects. About Hazardous Air Pollutants What are hazardous air pollutants? Health and Environmental ...

  5. California Air Basins

    Data.gov (United States)

    California Department of Resources — Air ResourcesCalifornia Air Resources BoardThe following datasets are from the California Air Resources Board: * arb_california_airbasins - California Air BasinsThe...

  6. Air conditioning and refrigeration engineering

    Energy Technology Data Exchange (ETDEWEB)

    Kreith, F. [ed.] [Univ. of Colorado, Boulder, CO (US)

    1999-12-01

    This book supplies the basics of design, from selecting the optimum system and equipment to preparing the drawings and specifications. It discusses the four phases of preparing a project: gathering information, developing alternatives, evaluating alternatives, and selling the best solution. In addition, the author breaks down the responsibilities of the engineer design documents, computer aided design, and government codes and standards. It provides you with an easy reference to all aspects of the topic. This resource addresses the most current areas of interest, such as computer aided design and drafting, desiccant air conditioning and energy conservation. It is a thorough and convenient guide to air conditioning and refrigeration engineering. Contents include: introduction; psychrometrics; air-conditioning processes and cycles; refrigerants and refrigeration cycles; outdoor design conditions and indoor design criteria; load calculations; air handling units and packaged units; refrigeration components and evaporative coolers; water systems; heating systems; refrigeration systems; thermal storage system; air system basics; absorption systems; air-conditioning systems and selection; and desiccant dehumidification and air-conditioning.

  7. 山西省实施煤电超低排放的空气质量效益模拟%A numerical simulation of the air quality improvement when all service coal -fired power plants maintain a ultra-low emission standard in Shanxi

    Institute of Scientific and Technical Information of China (English)

    谢卧龙; 崔艳丽

    2015-01-01

    In Shanxi province,50% of the air pol utants comes from coal-fired power plants.Shanxi provincial government has been asking al the service coal-fired power plants meet a ultra-low emission standard before 2020 , it's predictable that this policy wil improve the ambient air quality.It developes emission inventorys before and after the service coal-fired power plants maintain the ultra-low emission standard, and numerical y simu-lates the improvement of the ambient air quality, with the Calpuff model.Results indicate that there is an signifi-cantly decline of the pol ution contribution of service coal-fired power plants after maintaining the ultra-low e-mission standard in 11 districted cities, but non significant in the whole provincial area.To evidently improve the ambient air quality in the whole provincial area,other types of emission sources need more focus.%山西省煤电行业的大气污染物排放占到全省排放总量的将近50%,山西省政府要求2020年前现役机组进行超低排放改造,鉴于煤电产业的排放特点,现役机组实施超低排放对于空气质量将会有较大的影响。研究建立现有燃煤电厂超低排放实施前和实施后的排放源清单,利用Calpuff 模型对现役机组执行超低排放空气质量改善效益进行模拟。结果显示,在原标准下现役燃煤发电机组对11个设区市市区的空气质量浓度贡献较大,山西省平均来看贡献相对较小,现役燃煤发电机组执行超低排放后,11个设区市市区现役燃煤发电机组的空气质量浓度贡献值有明显的下降,但山西省平均的下降值相对较小,“十三五”期间的大气污染防治需更多的考虑对其他源的控制。

  8. Comments on: Chari, R.; Burke, T.A.; White, R.H.; Fox, M.A. Integrating Susceptibility into Environmental Policy: An Analysis of the National Ambient Air Quality Standard for Lead. Int. J. Environ. Res. Public Health 2012, 9, 1077-1096

    Directory of Open Access Journals (Sweden)

    Deirdre L. Murphy

    2013-02-01

    Full Text Available In their recent article [1], Chari et al. call attention to the important subject of setting National Ambient Air Quality Standards (NAAQS to provide requisite protection for public health, including the health of sensitive groups, as specified under the Clean Air Act (73 FR 66965 [2]. The authors focus on consideration of susceptibility to inform policy choices, using lead (Pb-related neurocognitive effects and children from low socioeconomic status (SES families in the context of alternative Pb standard levels. Our comments focus on the authors’ analysis of the scientific evidence and not on policy. We agree with the authors that the health effects evidence for Pb indicates a role (or roles for SES-related factors in influencing childhood Pb exposure and associated health effects. We disagree, however, with the authors’ interpretation of the literature on SES influence on the shape of the concentration-response (C-R relationship between children’s blood Pb and IQ (e.g., steepness of the slope. We further address aspects of the scientific evidence that are important to the consideration of sensitive populations in the context of the Pb NAAQS, and how the U.S. Environmental Protection Agency (EPA considered this evidence in setting the Pb NAAQS in 2008.

  9. 75 FR 9206 - Science Advisory Board Staff Office; Notification of a Clean Air Scientific Advisory Committee...

    Science.gov (United States)

    2010-03-01

    ... the Carbon Monoxide Primary National Ambient Air Quality Standards: Second External Review Draft and EPA's Policy Assessment for the Review of the Carbon Monoxide National Ambient Air Quality Standards... consultative advice on EPA's Plan for Review of the National Ambient Air Quality Standards for Carbon......

  10. China Cools with Tighter RAC Standards

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Jiang; Rosenquist, Gregory

    2006-06-01

    After boiling summer brought brown-out to most part of the country in 2004, China announced a new set of minimum energy efficiency standards for room air conditioners in September 2004, with the first tier going into effect on March 1, 2005 and the reach standard taking effect on January 1, 2009. This represents a milestone in China's standard setting process since the reach standard levels are significantly more stringent than previous standards for other appliances. This paper first analyzes cost-effectiveness of China's new standards for room air conditioners, and then attempts to evaluate the impact of the new standards on energy savings, electric generation capacity, and CO2 emissions reductions.

  11. Air pollution dispersion models as used in Poland in regional development planning

    Energy Technology Data Exchange (ETDEWEB)

    Pruchnicki, J.

    1977-02-01

    This paper discusses air pollution models used in regional development planning in Poland. After outlining the institutional structure and legislature dealing with air pollution control, the paper describes the air quality standards currently in effect. Dispersion models used in predicting air pollution concentrations are then detailed. Finally the application of air pollution modelling to urban design is discussed.

  12. Scope and implementation of standards ASME N510 / N511 in air treatment system (HVAC) of the Asco nuclear power plant; Alcance e implementacion de las normas ASME N511 en el sistema de tratamiento de aire (HVAC) de la central nuclear de Asco

    Energy Technology Data Exchange (ETDEWEB)

    Jaimot Jimenez, J. J.

    2013-07-01

    With the ITC for renewal of license units 1 and 2 of Asco, the CSN It required the commissioning tests underway in the air, according to ASME N510 filter units. It is required that, for safety-related units, to undertake preventive inspections according to ASME N511. All these requirements, in tight deadlines, have represented a great challenge for the organizations of maintenance and engineering of ANAV.

  13. Rooftop Unitary Air Conditioner with Integral Dedicated Outdoor Air System

    Energy Technology Data Exchange (ETDEWEB)

    Tiax Llc

    2006-02-28

    Energy use of rooftop and other unitary air-conditioners in commercial applications accounts for about 1 quad (10{sup 15} Btu) of primary energy use annually in the U.S. [Reference 7]. The realization that this cooling equipment accounts for the majority of commercial building cooled floorspace and the majority also of commercial building energy use has spurred development of improved-efficiency equipment as well as development of stricter standards addressing efficiency levels. Another key market driver affecting design of rooftop air-conditioning equipment has been concern regarding comfort and the control of humidity. Trends for increases in outdoor air ventilation rates in certain applications, and the increasing concern about indoor air quality problems associated with humidity levels and moisture in buildings points to a need for improved dehumidification capability in air-conditioning equipment of all types. In many cases addressing this issue exacerbates energy efficiency, and vice versa. The integrated dedicated outdoor air system configuration developed in this project addresses both energy and comfort/humidity issues.

  14. Standard deviations

    CERN Document Server

    Smith, Gary

    2015-01-01

    Did you know that having a messy room will make you racist? Or that human beings possess the ability to postpone death until after important ceremonial occasions? Or that people live three to five years longer if they have positive initials, like ACE? All of these ‘facts' have been argued with a straight face by researchers and backed up with reams of data and convincing statistics.As Nobel Prize-winning economist Ronald Coase once cynically observed, ‘If you torture data long enough, it will confess.' Lying with statistics is a time-honoured con. In Standard Deviations, ec

  15. Qualidade do ar em ambientes internos hospitalares: estudo de caso e análise crítica dos padrões atuais Indoor air quality in hospitals: a case study and a critical review of current standards

    Directory of Open Access Journals (Sweden)

    Marina Eller Quadros

    2009-09-01

    Full Text Available O objetivo deste trabalho foi avaliar a qualidade do ar em três categorias de ambientes hospitalares: unidade de terapia intensiva (UTI adulto, UTI neonatal (UTN e centro cirúrgico de um hospital em Florianópolis, Brasil. Avaliaram-se a concentração de dióxido de carbono, a vazão e renovação de ar nas salas do centro cirúrgico. A concentração de bioaerossóis foi estimada em um dia de avaliação para cada ambiente. Não se observou relação entre a concentração de bioaerossóis e o tempo de uso das salas de cirurgia. A concentração média de bioaerossóis foi de 231 UFC.m-3 para fungos e de 187 UFC.m-3 para bactérias. Os ambientes avaliados atendiam aos valores recomendados pela legislação vigente. Os resultados permitiram avaliar criticamente essa legislação e apresentar sugestões para estabelecimento de uma resolução específica para ambientes hospitalares no Brasil.The objective of this paper was to evaluate the air quality in three indoor hospital environments: a neonatal intensive care unit (ICU, an adult ICU and a surgical ward of a hospital in Florianópolis, Brazil. Carbon dioxide concentrations, exchange air flow rates as well as fungi and bacteria concentrations were measured in these rooms. Bioaerosol concentrations were evaluated throughout one-work day for each operating room. No relationship was observed between bioaerosol concentration and the period of use in the surgical ward. Average bioaerosol concentrations were of 231 UFC.m-3 for filamentous fungi and 187 UFC.m-3 for bacteria. All environments evaluated were, overall, in compliance with current legislations. Results allowed a critical review of the present regulations and suggestions for the establishment of a specific regulation for hospital environments in Brazil.

  16. Nuclear air cleaning programs in USA

    International Nuclear Information System (INIS)

    The paper describes air cleaning research activities in the United States nuclear program other than those described in the various papers presented at the conference. First described are those related to aerosol and particulate cleaning generic programs. Discussed next are air cleaning regulations and standards. Specific activities underway in developing air cleaning information and processes for specific areas are discussed beginning with the support of nuclear reactors, e.g., the Electric Power Research Institute programs on reactor accident phenomena and the Savannah River Site program related to aerosol and adsorber research. Finally, the limited research activities in support of air cleaning systems for nuclear fuel reprocessing are described

  17. Air movement and perceived air quality

    DEFF Research Database (Denmark)

    Melikov, Arsen Krikor; Kaczmarczyk, J.

    2012-01-01

    The impact of air movement on perceived air quality (PAQ) and sick building syndrome (SBS) symptoms was studied. In total, 124 human subjects participated in four series of experiments performed in climate chambers at different combinations of room air temperature (20, 23, 26 and 28 °C), relative...... humidity (30, 40 and 70%) and pollution level (low and high). Most of the experiments were performed with and without facially applied airflow at elevated velocity. The importance of the use of recirculated room air and clean, cool and dry outdoor air was studied. The exposures ranged from 60. min to 235....... min. Acceptability of PAQ and freshness of the air improved when air movement was applied. The elevated air movement diminished the negative impact of increased air temperature, relative humidity and pollution level on PAQ. The degree of improvement depended on the pollution level, the temperature...

  18. 40 CFR 63.783 - Standards.

    Science.gov (United States)

    2010-07-01

    ... appendix A to 40 CFR part 60 shall be used as the definitive measure for determining compliance. For the... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Standards. 63.783 Section 63.783... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES (CONTINUED) National...

  19. 49 CFR 91.11 - Standards.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Standards. 91.11 Section 91.11 Transportation Office of the Secretary of Transportation INTERNATIONAL AIR TRANSPORTATION FAIR COMPETITIVE PRACTICES § 91.11 Standards. (a) To minimize the burden of implementing this part on the United States, on...

  20. 40 CFR 63.703 - Standards.

    Science.gov (United States)

    2010-07-01

    ... discharge by at least the fraction removed (FR) specified in Table 9 of 40 CFR part 63, subpart G; or (ii... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Standards. 63.703 Section 63.703... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES (CONTINUED) National...