WorldWideScience

Sample records for accident consequence uncertainty

  1. Probabilistic accident consequence uncertainty analysis: Food chain uncertainty assessment. Volume 1: Main report

    This volume is the first of a two-volume document that summarizes a joint project conducted by the US Nuclear Regulatory Commission and the European Commission to assess uncertainties in the MACCS and COSYMA probabilistic accident consequence codes. These codes were developed primarily for estimating the risks presented by nuclear reactors based on postulated frequencies and magnitudes of potential accidents. This document reports on an ongoing project to assess uncertainty in the MACCS and COSYMA calculations for the offsite consequences of radionuclide releases by hypothetical nuclear power plant accidents. A panel of sixteen experts was formed to compile credible and traceable uncertainty distributions for food chain variables that affect calculations of offsite consequences. The expert judgment elicitation procedure and its outcomes are described in these volumes. Other panels were formed to consider uncertainty in other aspects of the codes. Their results are described in companion reports. Volume 1 contains background information and a complete description of the joint consequence uncertainty study. Volume 2 contains appendices that include (1) a summary of the MACCS and COSYMA consequence codes, (2) the elicitation questionnaires and case structures for both panels, (3) the rationales and results for the panels on soil and plant transfer and animal transfer, (4) short biographies of the experts, and (5) the aggregated results of their responses

  2. Probabilistic accident consequence uncertainty analysis: Food chain uncertainty assessment. Volume 1: Main report

    Brown, J. [National Radiological Protection Board (United Kingdom); Goossens, L.H.J.; Kraan, B.C.P. [Delft Univ. of Technology (Netherlands)] [and others

    1997-06-01

    This volume is the first of a two-volume document that summarizes a joint project conducted by the US Nuclear Regulatory Commission and the European Commission to assess uncertainties in the MACCS and COSYMA probabilistic accident consequence codes. These codes were developed primarily for estimating the risks presented by nuclear reactors based on postulated frequencies and magnitudes of potential accidents. This document reports on an ongoing project to assess uncertainty in the MACCS and COSYMA calculations for the offsite consequences of radionuclide releases by hypothetical nuclear power plant accidents. A panel of sixteen experts was formed to compile credible and traceable uncertainty distributions for food chain variables that affect calculations of offsite consequences. The expert judgment elicitation procedure and its outcomes are described in these volumes. Other panels were formed to consider uncertainty in other aspects of the codes. Their results are described in companion reports. Volume 1 contains background information and a complete description of the joint consequence uncertainty study. Volume 2 contains appendices that include (1) a summary of the MACCS and COSYMA consequence codes, (2) the elicitation questionnaires and case structures for both panels, (3) the rationales and results for the panels on soil and plant transfer and animal transfer, (4) short biographies of the experts, and (5) the aggregated results of their responses.

  3. Probabilistic accident consequence uncertainty analysis -- Early health effects uncertainty assessment. Volume 1: Main report

    Haskin, F.E. [Univ. of New Mexico, Albuquerque, NM (United States); Harper, F.T. [Sandia National Labs., Albuquerque, NM (United States); Goossens, L.H.J.; Kraan, B.C.P. [Delft Univ. of Technology (Netherlands); Grupa, J.B. [Netherlands Energy Research Foundation (Netherlands)

    1997-12-01

    The development of two new probabilistic accident consequence codes, MACCS and COSYMA, was completed in 1990. These codes estimate the consequence from the accidental releases of radiological material from hypothesized accidents at nuclear installations. In 1991, the US Nuclear Regulatory Commission and the Commission of the European Communities began cosponsoring a joint uncertainty analysis of the two codes. The ultimate objective of this joint effort was to systematically develop credible and traceable uncertainty distributions for the respective code input variables. A formal expert judgment elicitation and evaluation process was identified as the best technology available for developing a library of uncertainty distributions for these consequence parameters. This report focuses on the results of the study to develop distribution for variables related to the MACCS and COSYMA early health effects models.

  4. Probabilistic accident consequence uncertainty analysis -- Late health effects uncertainty assessment. Volume 1: Main report

    Little, M.P.; Muirhead, C.R. [National Radiological Protection Board (United Kingdom); Goossens, L.H.J.; Kraan, B.C.P.; Cooke, R.M. [Delft Univ. of Technology (Netherlands); Harper, F.T. [Sandia National Labs., Albuquerque, NM (United States); Hora, S.C. [Univ. of Hawaii, Hilo, HI (United States)

    1997-12-01

    The development of two new probabilistic accident consequence codes, MACCS and COSYMA, was completed in 1990. These codes estimate the consequence from the accidental releases of radiological material from hypothesized accidents at nuclear installations. In 1991, the US Nuclear Regulatory Commission and the Commission of the European Communities began cosponsoring a joint uncertainty analysis of the two codes. The ultimate objective of this joint effort was to systematically develop credible and traceable uncertainty distributions for the respective code input variables. A formal expert judgment elicitation and evaluation process was identified as the best technology available for developing a library of uncertainty distributions for these consequence parameters. This report focuses on the results of the study to develop distribution for variables related to the MACCS and COSYMA late health effects models.

  5. Probabilistic accident consequence uncertainty analysis -- Early health effects uncertainty assessment. Volume 2: Appendices

    Haskin, F.E. [Univ. of New Mexico, Albuquerque, NM (United States); Harper, F.T. [Sandia National Labs., Albuquerque, NM (United States); Goossens, L.H.J.; Kraan, B.C.P. [Delft Univ. of Technology (Netherlands)

    1997-12-01

    The development of two new probabilistic accident consequence codes, MACCS and COSYMA, was completed in 1990. These codes estimate the consequence from the accidental releases of radiological material from hypothesized accidents at nuclear installations. In 1991, the US Nuclear Regulatory Commission and the Commission of the European Communities began cosponsoring a joint uncertainty analysis of the two codes. The ultimate objective of this joint effort was to systematically develop credible and traceable uncertainty distributions for the respective code input variables. A formal expert judgment elicitation and evaluation process was identified as the best technology available for developing a library of uncertainty distributions for these consequence parameters. This report focuses on the results of the study to develop distribution for variables related to the MACCS and COSYMA early health effects models. This volume contains appendices that include (1) a summary of the MACCS and COSYMA consequence codes, (2) the elicitation questionnaires and case structures, (3) the rationales and results for the panel on early health effects, (4) short biographies of the experts, and (5) the aggregated results of their responses.

  6. Probabilistic accident consequence uncertainty analysis -- Uncertainty assessment for deposited material and external doses. Volume 2: Appendices

    Goossens, L.H.J.; Kraan, B.C.P.; Cooke, R.M. [Delft Univ. of Technology (Netherlands); Boardman, J. [AEA Technology (United Kingdom); Jones, J.A. [National Radiological Protection Board (United Kingdom); Harper, F.T.; Young, M.L. [Sandia National Labs., Albuquerque, NM (United States); Hora, S.C. [Univ. of Hawaii, Hilo, HI (United States)

    1997-12-01

    The development of two new probabilistic accident consequence codes, MACCS and COSYMA, was completed in 1990. These codes estimate the consequence from the accidental releases of radiological material from hypothesized accidents at nuclear installations. In 1991, the US Nuclear Regulatory Commission and the Commission of the European Communities began cosponsoring a joint uncertainty analysis of the two codes. The ultimate objective of this joint effort was to systematically develop credible and traceable uncertainty distributions for the respective code input variables. A formal expert judgment elicitation and evaluation process was identified as the best technology available for developing a library of uncertainty distributions for these consequence parameters. This report focuses on the results of the study to develop distribution for variables related to the MACCS and COSYMA deposited material and external dose models. This volume contains appendices that include (1) a summary of the MACCS and COSYMA consequence codes, (2) the elicitation questionnaires and case structures, (3) the rationales and results for the panel on deposited material and external doses, (4) short biographies of the experts, and (5) the aggregated results of their responses.

  7. Probabilistic accident consequence uncertainty analysis -- Uncertainty assessment for internal dosimetry. Volume 2: Appendices

    Goossens, L.H.J.; Kraan, B.C.P.; Cooke, R.M. [Delft Univ. of Technology (Netherlands); Harrison, J.D. [National Radiological Protection Board (United Kingdom); Harper, F.T. [Sandia National Labs., Albuquerque, NM (United States); Hora, S.C. [Univ. of Hawaii, Hilo, HI (United States)

    1998-04-01

    The development of two new probabilistic accident consequence codes, MACCS and COSYMA, was completed in 1990. These codes estimate the consequence from the accidental releases of radiological material from hypothesized accidents at nuclear installations. In 1991, the US Nuclear Regulatory Commission and the Commission of the European Communities began cosponsoring a joint uncertainty analysis of the two codes. The ultimate objective of this joint effort was to systematically develop credible and traceable uncertainty distributions for the respective code input variables. A formal expert judgment elicitation and evaluation process was identified as the best technology available for developing a library of uncertainty distributions for these consequence parameters. This report focuses on the results of the study to develop distribution for variables related to the MACCS and COSYMA internal dosimetry models. This volume contains appendices that include (1) a summary of the MACCS and COSYMA consequence codes, (2) the elicitation questionnaires and case structures, (3) the rationales and results for the panel on internal dosimetry, (4) short biographies of the experts, and (5) the aggregated results of their responses.

  8. Probabilistic accident consequence uncertainty analysis: Dispersion and deposition uncertainty assessment, appendices A and B

    Harper, F.T.; Young, M.L.; Miller, L.A. [Sandia National Labs., Albuquerque, NM (United States); Hora, S.C. [Univ. of Hawaii, Hilo, HI (United States); Lui, C.H. [Nuclear Regulatory Commission, Washington, DC (United States); Goossens, L.H.J.; Cooke, R.M. [Delft Univ. of Technology (Netherlands); Paesler-Sauer, J. [Research Center, Karlsruhe (Germany); Helton, J.C. [and others

    1995-01-01

    The development of two new probabilistic accident consequence codes, MACCS and COSYMA, completed in 1990, estimate the risks presented by nuclear installations based on postulated frequencies and magnitudes of potential accidents. In 1991, the US Nuclear Regulatory Commission (NRC) and the Commission of the European Communities (CEC) began a joint uncertainty analysis of the two codes. The objective was to develop credible and traceable uncertainty distributions for the input variables of the codes. Expert elicitation, developed independently, was identified as the best technology available for developing a library of uncertainty distributions for the selected consequence parameters. The study was formulated jointly and was limited to the current code models and to physical quantities that could be measured in experiments. To validate the distributions generated for the wet deposition input variables, samples were taken from these distributions and propagated through the wet deposition code model along with the Gaussian plume model (GPM) implemented in the MACCS and COSYMA codes. Resulting distributions closely replicated the aggregated elicited wet deposition distributions. Project teams from the NRC and CEC cooperated successfully to develop and implement a unified process for the elaboration of uncertainty distributions on consequence code input parameters. Formal expert judgment elicitation proved valuable for synthesizing the best available information. Distributions on measurable atmospheric dispersion and deposition parameters were successfully elicited from experts involved in the many phenomenological areas of consequence analysis. This volume is the second of a three-volume document describing the project and contains two appendices describing the rationales for the dispersion and deposition data along with short biographies of the 16 experts who participated in the project.

  9. Probabilistic accident consequence uncertainty analysis: Dispersion and deposition uncertainty assessment, appendices A and B

    The development of two new probabilistic accident consequence codes, MACCS and COSYMA, completed in 1990, estimate the risks presented by nuclear installations based on postulated frequencies and magnitudes of potential accidents. In 1991, the US Nuclear Regulatory Commission (NRC) and the Commission of the European Communities (CEC) began a joint uncertainty analysis of the two codes. The objective was to develop credible and traceable uncertainty distributions for the input variables of the codes. Expert elicitation, developed independently, was identified as the best technology available for developing a library of uncertainty distributions for the selected consequence parameters. The study was formulated jointly and was limited to the current code models and to physical quantities that could be measured in experiments. To validate the distributions generated for the wet deposition input variables, samples were taken from these distributions and propagated through the wet deposition code model along with the Gaussian plume model (GPM) implemented in the MACCS and COSYMA codes. Resulting distributions closely replicated the aggregated elicited wet deposition distributions. Project teams from the NRC and CEC cooperated successfully to develop and implement a unified process for the elaboration of uncertainty distributions on consequence code input parameters. Formal expert judgment elicitation proved valuable for synthesizing the best available information. Distributions on measurable atmospheric dispersion and deposition parameters were successfully elicited from experts involved in the many phenomenological areas of consequence analysis. This volume is the second of a three-volume document describing the project and contains two appendices describing the rationales for the dispersion and deposition data along with short biographies of the 16 experts who participated in the project

  10. Probabilistic accident consequence uncertainty analysis: Dispersion and deposition uncertainty assessment, main report

    Harper, F.T.; Young, M.L.; Miller, L.A. [Sandia National Labs., Albuquerque, NM (United States); Hora, S.C. [Univ. of Hawaii, Hilo, HI (United States); Lui, C.H. [Nuclear Regulatory Commission, Washington, DC (United States); Goossens, L.H.J.; Cooke, R.M. [Delft Univ. of Technology (Netherlands); Paesler-Sauer, J. [Research Center, Karlsruhe (Germany); Helton, J.C. [and others

    1995-01-01

    The development of two new probabilistic accident consequence codes, MACCS and COSYMA, was completed in 1990. These codes estimate the risks presented by nuclear installations based on postulated frequencies and magnitudes of potential accidents. In 1991, the US Nuclear Regulatory Commission (NRC) and the Commission of the European Communities (CEC) began a joint uncertainty analysis of the two codes. The ultimate objective of the joint effort was to develop credible and traceable uncertainty distributions for the input variables of the codes. Expert elicitation was identified as the best technology available for developing a library of uncertainty distributions for the selected consequence parameters. The study was formulated jointly and was limited to the current code models and to physical quantities that could be measured in experiments. Experts developed their distributions independently. To validate the distributions generated for the wet deposition input variables, samples were taken from these distributions and propagated through the wet deposition code model. Resulting distributions closely replicated the aggregated elicited wet deposition distributions. To validate the distributions generated for the dispersion code input variables, samples from the distributions and propagated through the Gaussian plume model (GPM) implemented in the MACCS and COSYMA codes. Project teams from the NRC and CEC cooperated successfully to develop and implement a unified process for the elaboration of uncertainty distributions on consequence code input parameters. Formal expert judgment elicitation proved valuable for synthesizing the best available information. Distributions on measurable atmospheric dispersion and deposition parameters were successfully elicited from experts involved in the many phenomenological areas of consequence analysis. This volume is the first of a three-volume document describing the project.

  11. Probabilistic accident consequence uncertainty analysis: Dispersion and deposition uncertainty assessment, main report

    The development of two new probabilistic accident consequence codes, MACCS and COSYMA, was completed in 1990. These codes estimate the risks presented by nuclear installations based on postulated frequencies and magnitudes of potential accidents. In 1991, the US Nuclear Regulatory Commission (NRC) and the Commission of the European Communities (CEC) began a joint uncertainty analysis of the two codes. The ultimate objective of the joint effort was to develop credible and traceable uncertainty distributions for the input variables of the codes. Expert elicitation was identified as the best technology available for developing a library of uncertainty distributions for the selected consequence parameters. The study was formulated jointly and was limited to the current code models and to physical quantities that could be measured in experiments. Experts developed their distributions independently. To validate the distributions generated for the wet deposition input variables, samples were taken from these distributions and propagated through the wet deposition code model. Resulting distributions closely replicated the aggregated elicited wet deposition distributions. To validate the distributions generated for the dispersion code input variables, samples from the distributions and propagated through the Gaussian plume model (GPM) implemented in the MACCS and COSYMA codes. Project teams from the NRC and CEC cooperated successfully to develop and implement a unified process for the elaboration of uncertainty distributions on consequence code input parameters. Formal expert judgment elicitation proved valuable for synthesizing the best available information. Distributions on measurable atmospheric dispersion and deposition parameters were successfully elicited from experts involved in the many phenomenological areas of consequence analysis. This volume is the first of a three-volume document describing the project

  12. An Analysis of the Cumulative Uncertainty Associated with a Quantitative Consequence Assessment of a Major Accident

    JIRSA PAVEL

    2005-01-01

    The task of the article is to quantify the uncertainty of the possible results of the accident consequence assessment of the chemical production plant and to provide some description of potentional problems with literature references and examples to help to avoid the erroneous use of available formulas. Based on numbers presented in the article we may conclude, that the main source of uncertainty in the consequence analysis of chemical accident assessment is surprisingly not only the dispers...

  13. Probabilistic accident consequence uncertainty analysis: Food chain uncertainty assessment. Volume 2: Appendices

    This volume is the second of a two-volume document that summarizes a joint project by the US Nuclear Regulatory and the Commission of European Communities to assess uncertainties in the MACCS and COSYMA probabilistic accident consequence codes. These codes were developed primarily for estimating the risks presented by nuclear reactors based on postulated frequencies and magnitudes of potential accidents. This two-volume report, which examines mechanisms and uncertainties of transfer through the food chain, is the first in a series of five such reports. A panel of sixteen experts was formed to compile credible and traceable uncertainty distributions for food chain transfer that affect calculations of offsite radiological consequences. Seven of the experts reported on transfer into the food chain through soil and plants, nine reported on transfer via food products from animals, and two reported on both. The expert judgment elicitation procedure and its outcomes are described in these volumes. This volume contains seven appendices. Appendix A presents a brief discussion of the MAACS and COSYMA model codes. Appendix B is the structure document and elicitation questionnaire for the expert panel on soils and plants. Appendix C presents the rationales and responses of each of the members of the soils and plants expert panel. Appendix D is the structure document and elicitation questionnaire for the expert panel on animal transfer. The rationales and responses of each of the experts on animal transfer are given in Appendix E. Brief biographies of the food chain expert panel members are provided in Appendix F. Aggregated results of expert responses are presented in graph format in Appendix G

  14. Probabilistic accident consequence uncertainty analysis: Food chain uncertainty assessment. Volume 2: Appendices

    Brown, J. [National Radiological Protection Board (United Kingdom); Goossens, L.H.J.; Kraan, B.C.P. [Delft Univ. of Technology (Netherlands)] [and others

    1997-06-01

    This volume is the second of a two-volume document that summarizes a joint project by the US Nuclear Regulatory and the Commission of European Communities to assess uncertainties in the MACCS and COSYMA probabilistic accident consequence codes. These codes were developed primarily for estimating the risks presented by nuclear reactors based on postulated frequencies and magnitudes of potential accidents. This two-volume report, which examines mechanisms and uncertainties of transfer through the food chain, is the first in a series of five such reports. A panel of sixteen experts was formed to compile credible and traceable uncertainty distributions for food chain transfer that affect calculations of offsite radiological consequences. Seven of the experts reported on transfer into the food chain through soil and plants, nine reported on transfer via food products from animals, and two reported on both. The expert judgment elicitation procedure and its outcomes are described in these volumes. This volume contains seven appendices. Appendix A presents a brief discussion of the MAACS and COSYMA model codes. Appendix B is the structure document and elicitation questionnaire for the expert panel on soils and plants. Appendix C presents the rationales and responses of each of the members of the soils and plants expert panel. Appendix D is the structure document and elicitation questionnaire for the expert panel on animal transfer. The rationales and responses of each of the experts on animal transfer are given in Appendix E. Brief biographies of the food chain expert panel members are provided in Appendix F. Aggregated results of expert responses are presented in graph format in Appendix G.

  15. Techniques Applied in the COSYMA Accident Consequence Uncertainty Analysis (invited paper)

    Uncertainty and sensitivity analysis studies for the program package COSYMA for assessing the radiological consequences of nuclear accidents have been performed to obtain a deeper insight into the propagation of parameter uncertainties through different submodules and to quantify their contribution to uncertainty and sensitivity in a final overall uncertainty analysis of the complete program system COSYMA. Some strategies are given for performing uncertainty analysis runs for submodules and/or the complete complex program system COSYMA and guidelines explain how to post-process and to reduce the bulk of uncertainty and sensitivity analysis results. (author)

  16. Aspects of uncertainty analysis in accident consequence modeling

    Mathematical models are frequently used to determine probable dose to man from an accidental release of radionuclides by a nuclear facility. With increased emphasis on the accuracy of these models, the incorporation of uncertainty analysis has become one of the most crucial and sensitive components in evaluating the significance of model predictions. In the present paper, we address three aspects of uncertainty in models used to assess the radiological impact to humans: uncertainties resulting from the natural variability in human biological parameters; the propagation of parameter variability by mathematical models; and comparison of model predictions to observational data

  17. Probabilistic Accident Consequence Uncertainty Analysis of the Whole Program Package COSYMA (invited paper)

    The overall uncertainty analysis of the program package COSYMA for assessing the radiological consequences of nuclear accidents builds on the results of a series of individual uncertainty and sensitivity analyses of its submodules. A set of 186 model parameters was identified which contribute most to the uncertainties of endpoints. Probabilistic accident consequence assessments with 144 weather sequences were performed for each of 300 sample sets derived from the uncertainty distributions of these parameters by Latin hypercube sampling. The evaluation of the results provided confidence bounds for the complementary cumulative frequency distributions of endpoints for three different source terms covering a wide range of release fractions. Concluding sensitivity analyses identified the most important model parameters responsible for the uncertainties of endpoints. (author)

  18. Probabilistic Accident Consequence Uncertainty Analysis of the Dose Calculations Module in the COSYMA Package (invited paper)

    Uncertainty analysis of the dose calculation module of the COSYMA accident consequence assessment code has been undertaken, involving the following steps: (1) Expert judgement techniques were applied to assess uncertainties in measurable parameters determining external and internal doses. (2) The data obtained were used to calculate distributions on the dose quantities required as code input parameters. (3) The effect of uncertainties in dose quantities was analysed for a range of COSYMA end points, including the extent of countermeasures and incidences of early and late health effects, and the most important uncertainties were identified for inclusion in an overall uncertainty analysis of COSYMA. Parameters identified as making the largest contributions to uncertainty included external doses and location factors, residence times of materials on skin, breathing rates, and respiratory tract deposition and retention parameters, for the extent of countermeasures and early health effects, and caesium and iodine retention parameters for late effects. (author)

  19. Uncertainty and sensitivity analysis of chronic exposure results with the MACCS reactor accident consequence model

    Uncertainty and sensitivity analysis techniques based on Latin hypercube sampling, partial correlation analysis and stepwise regression analysis are used in an investigation with the MACCS model of the chronic exposure pathways associated with a severe accident at a nuclear power station. The primary purpose of this study is to provide guidance on the variables to be considered in future review work to reduce the uncertainty in the important variables used in the calculation of reactor accident consequences. The effects of 75 imprecisely known input variables on the following reactor accident consequences are studied: crop growing-season dose, crop long-term dose, water ingestion dose, milk growing-season dose, long-term groundshine dose, long-term inhalation dose, total food pathways dose, total ingestion pathways dose, total long-term pathways dose, total latent cancer fatalities, area-dependent cost, crop disposal cost, milk disposal cost, population-dependent cost, total economic cost, condemnation area, condemnation population, crop disposal area and milk disposal area. When the predicted variables are considered collectively, the following input variables were found to be the dominant contributors to uncertainty: dry deposition velocity, transfer of cesium from animal feed to milk, transfer of cesium from animal feed to meet, ground concentration of Cs-134 at which the disposal of milk products will be initiated, transfer of Sr-90 from soil to legumes, maximum allowable ground concentration of Sr-90 for production of crops, fraction of cesium entering surface water that is consumed in drinking water, groundshine shielding factor, scale factor defining resuspension, dose reduction associated with decontamination, and ground concentration of I-131 at which disposal of crops will be initiated due to accidents that occur during the growing season. Reducing the uncertainty in the preceding variables was found to substantially reduce the uncertainty in the

  20. Probabilistic accident consequence uncertainty analysis -- Late health effects uncertain assessment. Volume 2: Appendices

    Little, M.P.; Muirhead, C.R. [National Radiological Protection Board (United Kingdom); Goossens, L.H.J.; Kraan, B.C.P.; Cooke, R.M. [Delft Univ. of Technology (Netherlands); Harper, F.T. [Sandia National Labs., Albuquerque, NM (United States); Hora, S.C. [Univ. of Hawaii, Hilo, HI (United States)

    1997-12-01

    The development of two new probabilistic accident consequence codes, MACCS and COSYMA, was completed in 1990. These codes estimate the consequence from the accidental releases of radiological material from hypothesized accidents at nuclear installations. In 1991, the US Nuclear Regulatory Commission and the Commission of the European Communities began cosponsoring a joint uncertainty analysis of the two codes. The ultimate objective of this joint effort was to systematically develop credible and traceable uncertainty distributions for the respective code input variables. A formal expert judgment elicitation and evaluation process was identified as the best technology available for developing a library of uncertainty distributions for these consequence parameters. This report focuses on the results of the study to develop distribution for variables related to the MACCS and COSYMA late health effects models. This volume contains appendices that include (1) a summary of the MACCS and COSYMA consequence codes, (2) the elicitation questionnaires and case structures, (3) the rationales and results for the expert panel on late health effects, (4) short biographies of the experts, and (5) the aggregated results of their responses.

  1. Uncertainty analysis with a view towards applications in accident consequence assessments

    Since the publication of the US-Reactor Safety Study WASH-1400 there has been an increasing interest to develop and apply methods which allow to quantify the uncertainty inherent in probabilistic risk assessments (PRAs) and accident consequence assessments (ACAs) for installations of the nuclear fuel cycle. Research and development in this area is forced by the fact that PRA and ACA are more and more used for comparative, decisive and fact finding studies initiated by industry and regulatory commissions. This report summarizes and reviews some of the main methods and gives some hints to do sensitivity and uncertainty analyses. Some first investigations aiming at the application of the method mentioned above to a submodel of the ACA-code UFOMOD (KfK) are presented. Sensitivity analyses and some uncertainty studies an important submodel of UFOMOD are carried out to identify the relevant parameters for subsequent uncertainty calculations. (orig./HP)

  2. Uncertainty and sensitivity analysis of early exposure results with the MACCS Reactor Accident Consequence Model

    Helton, J.C. [Arizona State Univ., Tempe, AZ (United States); Johnson, J.D. [GRAM, Inc., Albuquerque, NM (United States); McKay, M.D. [Los Alamos National Lab., NM (United States); Shiver, A.W.; Sprung, J.L. [Sandia National Labs., Albuquerque, NM (United States)

    1995-01-01

    Uncertainty and sensitivity analysis techniques based on Latin hypercube sampling, partial correlation analysis and stepwise regression analysis are used in an investigation with the MACCS model of the early health effects associated with a severe accident at a nuclear power station. The primary purpose of this study is to provide guidance on the variables to be considered in future review work to reduce the uncertainty in the important variables used in the calculation of reactor accident consequences. The effects of 34 imprecisely known input variables on the following reactor accident consequences are studied: number of early fatalities, number of cases of prodromal vomiting, population dose within 10 mi of the reactor, population dose within 1000 mi of the reactor, individual early fatality probability within 1 mi of the reactor, and maximum early fatality distance. When the predicted variables are considered collectively, the following input variables were found to be the dominant contributors to uncertainty: scaling factor for horizontal dispersion, dry deposition velocity, inhalation protection factor for nonevacuees, groundshine shielding factor for nonevacuees, early fatality hazard function alpha value for bone marrow exposure, and scaling factor for vertical dispersion.

  3. Uncertainty and sensitivity analysis of early exposure results with the MACCS Reactor Accident Consequence Model

    Uncertainty and sensitivity analysis techniques based on Latin hypercube sampling, partial correlation analysis and stepwise regression analysis are used in an investigation with the MACCS model of the early health effects associated with a severe accident at a nuclear power station. The primary purpose of this study is to provide guidance on the variables to be considered in future review work to reduce the uncertainty in the important variables used in the calculation of reactor accident consequences. The effects of 34 imprecisely known input variables on the following reactor accident consequences are studied: number of early fatalities, number of cases of prodromal vomiting, population dose within 10 mi of the reactor, population dose within 1000 mi of the reactor, individual early fatality probability within 1 mi of the reactor, and maximum early fatality distance. When the predicted variables are considered collectively, the following input variables were found to be the dominant contributors to uncertainty: scaling factor for horizontal dispersion, dry deposition velocity, inhalation protection factor for nonevacuees, groundshine shielding factor for nonevacuees, early fatality hazard function alpha value for bone marrow exposure, and scaling factor for vertical dispersion

  4. Expert Judgement for a Probabilistic Accident Consequence Uncertainty Analysis (invited paper)

    The development of two probabilistic accident consequence codes sponsored by the European Commission and the United States Nuclear Regulatory Commission, COSYMA and MACCS respectively, was completed in 1990. These codes estimate the risks and other endpoints associated with accidents from hypothesised nuclear installations. In 1991, both Commissions sponsored a joint project for an uncertainty analysis of these two codes. The main objective of this joint project was systematically to derive credible and traceable probability distributions for the respective code input variables. These input distributions will subsequently be used in two uncertainty analyses for each code separately. A formal expert judgement elicitation and evacuation process was used as the best available technique to accomplish that objective. This paper shows the overall process and reports on experiences of elicitors and experts of the eight expert judgement exercises performed under the joint study. (author)

  5. Uncertainty and sensitivity analysis of food pathway results with the MACCS Reactor Accident Consequence Model

    Uncertainty and sensitivity analysis techniques based on Latin hypercube sampling, partial correlation analysis and stepwise regression analysis are used in an investigation with the MACCS model of the food pathways associated with a severe accident at a nuclear power station. The primary purpose of this study is to provide guidance on the variables to be considered in future review work to reduce the uncertainty in the important variables used in the calculation of reactor accident consequences. The effects of 87 imprecisely-known input variables on the following reactor accident consequences are studied: crop growing season dose, crop long-term dose, milk growing season dose, total food pathways dose, total ingestion pathways dose, total long-term pathways dose, area dependent cost, crop disposal cost, milk disposal cost, condemnation area, crop disposal area and milk disposal area. When the predicted variables are considered collectively, the following input variables were found to be the dominant contributors to uncertainty: fraction of cesium deposition on grain fields that is retained on plant surfaces and transferred directly to grain, maximum allowable ground concentrations of Cs-137 and Sr-90 for production of crops, ground concentrations of Cs-134, Cs-137 and I-131 at which the disposal of milk will be initiated due to accidents that occur during the growing season, ground concentrations of Cs-134, I-131 and Sr-90 at which the disposal of crops will be initiated due to accidents that occur during the growing season, rate of depletion of Cs-137 and Sr-90 from the root zone, transfer of Sr-90 from soil to legumes, transfer of Cs-137 from soil to pasture, transfer of cesium from animal feed to meat, and the transfer of cesium, iodine and strontium from animal feed to milk

  6. Uncertainty and sensitivity analysis of food pathway results with the MACCS Reactor Accident Consequence Model

    Helton, J.C. [Arizona State Univ., Tempe, AZ (United States); Johnson, J.D.; Rollstin, J.A. [GRAM, Inc., Albuquerque, NM (United States); Shiver, A.W.; Sprung, J.L. [Sandia National Labs., Albuquerque, NM (United States)

    1995-01-01

    Uncertainty and sensitivity analysis techniques based on Latin hypercube sampling, partial correlation analysis and stepwise regression analysis are used in an investigation with the MACCS model of the food pathways associated with a severe accident at a nuclear power station. The primary purpose of this study is to provide guidance on the variables to be considered in future review work to reduce the uncertainty in the important variables used in the calculation of reactor accident consequences. The effects of 87 imprecisely-known input variables on the following reactor accident consequences are studied: crop growing season dose, crop long-term dose, milk growing season dose, total food pathways dose, total ingestion pathways dose, total long-term pathways dose, area dependent cost, crop disposal cost, milk disposal cost, condemnation area, crop disposal area and milk disposal area. When the predicted variables are considered collectively, the following input variables were found to be the dominant contributors to uncertainty: fraction of cesium deposition on grain fields that is retained on plant surfaces and transferred directly to grain, maximum allowable ground concentrations of Cs-137 and Sr-90 for production of crops, ground concentrations of Cs-134, Cs-137 and I-131 at which the disposal of milk will be initiated due to accidents that occur during the growing season, ground concentrations of Cs-134, I-131 and Sr-90 at which the disposal of crops will be initiated due to accidents that occur during the growing season, rate of depletion of Cs-137 and Sr-90 from the root zone, transfer of Sr-90 from soil to legumes, transfer of Cs-137 from soil to pasture, transfer of cesium from animal feed to meat, and the transfer of cesium, iodine and strontium from animal feed to milk.

  7. Uncertainty and sensitivity analysis of chronic exposure results with the MACCS reactor accident consequence model

    Uncertainty and sensitivity analysis techniques based on Latin hypercube sampling, partial correlation analysis and stepwise regression analysis are used in an investigation with the MACCS model of the chronic exposure pathways associated with a severe accident at a nuclear power station. The primary purpose of this study is to provide guidance on the variables to be considered in future review work to reduce the uncertainty in the important variables used in the calculation of reactor accident consequences. The effects of 75 imprecisely known input variables on the following reactor accident consequences are studied: crop growing season dose, crop long-term dose, water ingestion dose, milk growing season dose, long-term groundshine dose, long-term inhalation dose, total food pathways dose, total ingestion pathways dose, total long-term pathways dose, total latent cancer fatalities, area-dependent cost, crop disposal cost, milk disposal cost, population-dependent cost, total economic cost, condemnation area, condemnation population, crop disposal area and milk disposal area. When the predicted variables are considered collectively, the following input variables were found to be the dominant contributors to uncertainty: dry deposition velocity, transfer of cesium from animal feed to milk, transfer of cesium from animal feed to meat, ground concentration of Cs-134 at which the disposal of milk products will be initiated, transfer of Sr-90 from soil to legumes, maximum allowable ground concentration of Sr-90 for production of crops, fraction of cesium entering surface water that is consumed in drinking water, groundshine shielding factor, scale factor defining resuspension, dose reduction associated with decontamination, and ground concentration of 1-131 at which disposal of crops will be initiated due to accidents that occur during the growing season

  8. Uncertainty and sensitivity analysis of chronic exposure results with the MACCS reactor accident consequence model

    Helton, J.C. [Arizona State Univ., Tempe, AZ (United States); Johnson, J.D.; Rollstin, J.A. [Gram, Inc., Albuquerque, NM (United States); Shiver, A.W.; Sprung, J.L. [Sandia National Labs., Albuquerque, NM (United States)

    1995-01-01

    Uncertainty and sensitivity analysis techniques based on Latin hypercube sampling, partial correlation analysis and stepwise regression analysis are used in an investigation with the MACCS model of the chronic exposure pathways associated with a severe accident at a nuclear power station. The primary purpose of this study is to provide guidance on the variables to be considered in future review work to reduce the uncertainty in the important variables used in the calculation of reactor accident consequences. The effects of 75 imprecisely known input variables on the following reactor accident consequences are studied: crop growing season dose, crop long-term dose, water ingestion dose, milk growing season dose, long-term groundshine dose, long-term inhalation dose, total food pathways dose, total ingestion pathways dose, total long-term pathways dose, total latent cancer fatalities, area-dependent cost, crop disposal cost, milk disposal cost, population-dependent cost, total economic cost, condemnation area, condemnation population, crop disposal area and milk disposal area. When the predicted variables are considered collectively, the following input variables were found to be the dominant contributors to uncertainty: dry deposition velocity, transfer of cesium from animal feed to milk, transfer of cesium from animal feed to meat, ground concentration of Cs-134 at which the disposal of milk products will be initiated, transfer of Sr-90 from soil to legumes, maximum allowable ground concentration of Sr-90 for production of crops, fraction of cesium entering surface water that is consumed in drinking water, groundshine shielding factor, scale factor defining resuspension, dose reduction associated with decontamination, and ground concentration of 1-131 at which disposal of crops will be initiated due to accidents that occur during the growing season.

  9. Probabilistic accident consequence uncertainty analysis: Dispersion and deposition uncertainty assessment. Volume 3, Appendices C, D, E, F, and G

    The development of two new probabilistic accident consequence codes, MACCS and COSYMA, completed in 1990, estimate the risks presented by nuclear installations based on postulated frequencies and magnitudes of potential accidents. In 1991, the US Nuclear Regulatory Commission (NRC) and the Commission of the European Communities (CEC) began a joint uncertainty analysis of the two codes. The objective was to develop credible and traceable uncertainty distributions for the input variables of the codes. Expert elicitation, developed independently, was identified as the best technology available for developing a library of uncertainty distributions for the selected consequence parameters. The study was formulated jointly and was limited to the current code models and to physical quantities that could be measured in experiments. To validate the distributions generated for the wet deposition input variables, samples were taken from these distributions and propagated through the wet deposition code model along with the Gaussian plume model (GPM) implemented in the MACCS and COSYMA codes. Resulting distributions closely replicated the aggregated elicited wet deposition distributions. Project teams from the NRC and CEC cooperated successfully to develop and implement a unified process for the elaboration of uncertainty distributions on consequence code input parameters. Formal expert judgment elicitation proved valuable for synthesizing the best available information. Distributions on measurable atmospheric dispersion and deposition parameters were successfully elicited from experts involved in the many phenomenological areas of consequence analysis. This volume is the third of a three-volume document describing the project and contains descriptions of the probability assessment principles; the expert identification and selection process; the weighting methods used; the inverse modeling methods; case structures; and summaries of the consequence codes

  10. Probabilistic accident consequence uncertainty analysis: Dispersion and deposition uncertainty assessment. Volume 3, Appendices C, D, E, F, and G

    Harper, F.T.; Young, M.L.; Miller, L.A. [Sandia National Labs., Albuquerque, NM (United States)] [and others

    1995-01-01

    The development of two new probabilistic accident consequence codes, MACCS and COSYMA, completed in 1990, estimate the risks presented by nuclear installations based on postulated frequencies and magnitudes of potential accidents. In 1991, the US Nuclear Regulatory Commission (NRC) and the Commission of the European Communities (CEC) began a joint uncertainty analysis of the two codes. The objective was to develop credible and traceable uncertainty distributions for the input variables of the codes. Expert elicitation, developed independently, was identified as the best technology available for developing a library of uncertainty distributions for the selected consequence parameters. The study was formulated jointly and was limited to the current code models and to physical quantities that could be measured in experiments. To validate the distributions generated for the wet deposition input variables, samples were taken from these distributions and propagated through the wet deposition code model along with the Gaussian plume model (GPM) implemented in the MACCS and COSYMA codes. Resulting distributions closely replicated the aggregated elicited wet deposition distributions. Project teams from the NRC and CEC cooperated successfully to develop and implement a unified process for the elaboration of uncertainty distributions on consequence code input parameters. Formal expert judgment elicitation proved valuable for synthesizing the best available information. Distributions on measurable atmospheric dispersion and deposition parameters were successfully elicited from experts involved in the many phenomenological areas of consequence analysis. This volume is the third of a three-volume document describing the project and contains descriptions of the probability assessment principles; the expert identification and selection process; the weighting methods used; the inverse modeling methods; case structures; and summaries of the consequence codes.

  11. Analysis of uncertainties caused by the atmospheric dispersion model in accident consequence assessments with UFOMOD

    Various techniques available for uncertainty analysis of large computer models are applied, described and selected as most appropriate for analyzing the uncertainty in the predictions of accident consequence assessments. The investigation refers to the atmospheric dispersion and deposition submodel (straight-line Gaussian plume model) of UFOMOD, whose most important input variables and parameters are linked with probability distributions derived from expert judgement. Uncertainty bands show how much variability exists, sensitivity measures determine what causes this variability in consequences. Results are presented as confidence bounds of complementary cumulative frequency distributions (CCFDs) of activity concentrations, organ doses and health effects, partially as a function of distance from the site. In addition the ranked influence of the uncertain parameters on the different consequence types is shown. For the estimation of confidence bounds it was sufficient to choose a model parameter sample size of n (n=59) equal to 1.5 times the number of uncertain model parameters. Different samples or an increase of sample size did not change the 5%-95% - confidence bands. To get statistically stable results of the sensitivity analysis, larger sample sizes are needed (n=100, 200). Random or Latin-hypercube sampling schemes as tools for uncertainty and sensitivity analyses led to comparable results. (orig.)

  12. Critique of and Limitations on the Use of Expert Judgements in Accident Consequence Uncertainty Analysis (invited paper)

    Accident consequence models are designed primarily to be used in support of siting and licensing decisions. To use these models, the analyst inevitably requires some input from experts. Equally, to understand the implication of the models, the analyst needs to explore their sensitivity to the inputs and uncertainty analysis is a key tool in doing this. In this paper, the interplay between these two aspects of the use of accident consequence models is considered, paying particular attention to issues and limitations that require further research in the coming years. (author)

  13. Probabilistic Accident Consequence Uncertainty Analysis of the Food Chain Module in the COSYMA Package (invited paper)

    This paper describes the uncertainty analysis of the food chain module of COSYMA and the uncertainty distributions on the input parameter values for the food chain model provided by the expert panels that were used for the analysis. Two expert panels were convened, covering the areas of soil and plant transfer processes and transfer to and through animals. The aggregated uncertainty distributions from the experts for the elicited variables were used in an uncertainty analysis of the food chain module of COSYMA. The main aim of the module analysis was to identify those parameters whose uncertainty makes large contributions to the overall uncertainty and so should be included in the overall analysis. (author)

  14. Uncertainties in offsite consequence analysis

    Young, M.L.; Harper, F.T.; Lui, C.H.

    1996-03-01

    The development of two new probabilistic accident consequence codes, MACCS and COSYMA, was completed in 1990. These codes estimate the consequences from the accidental releases of radiological material from hypothesized accidents at nuclear installations. In 1991, the U.S. Nuclear Regulatory Commission and the European Commission began co-sponsoring a joint uncertainty analysis of the two codes. The ultimate objective of this joint effort was to systematically develop credible and traceable uncertainty distributions for the respective code input variables using a formal expert judgment elicitation and evaluation process. This paper focuses on the methods used in and results of this on-going joint effort.

  15. The Chernobyl accident consequences

    Five teen years later, Tchernobyl remains the symbol of the greater industrial nuclear accident. To take stock on this accident, this paper proposes a chronology of the events and presents the opinion of many international and national organizations. It provides also web sites references concerning the environmental and sanitary consequences of the Tchernobyl accident, the economic actions and propositions for the nuclear safety improvement in the East Europe. (A.L.B.)

  16. Accidents, risks and consequences

    Although the accident at Chernobyl can be considered as the worst accident in the world, it could have been worse. Other far worse situations are considered, such as a nuclear weapon hitting a nuclear reactor. Indeed the accident at Chernobyl is compared to a nuclear weapon. The consequences of Chernobyl in terms of radiation levels are discussed. Although it is believed that a similar accident could not occur in the United Kingdom, that possibility is considered. It is suggested that emergency plans should be made for just such an eventuality. Even if Chernobyl could not happen in the UK, the effects of accidents are international. The way in which nuclear reactor accidents happen is explored, taking the 1957 Windscale fire, Three Mile Island and Chernobyl as examples. Reactor designs and accident scenarios are considered. The different reactor designs are listed. As well as the Chernobyl RBMK design it is suggested that the light water reactors also have undesirable features from the point of view of safety. (U.K.)

  17. Lessons learnt from the EC/USNRC expert judgement study on probabilistic accident consequence codes applied in the COSYMA uncertainty analyses

    Two probabilistic accident consequence codes, COSYMA and MACCS respectively, estimate the risks and other endpoints associated with hypothetical accidents from nuclear installations. A joint EC/USNRC project for an uncertainty analysis of these two codes was initiated to systematically derive credible and traceable probability distributions for the respective code input variables. A formal expert judgement elicitation and evaluation process was used as the best available technique to accomplish that objective. These input distributions were used in an uncertainty analysis of the COSYMA package. This paper will show the overall process and highlights the lessons learnt from the projects. (author)

  18. Probabilistic Accident Consequence Uncertainty Analysis of the Early Health Effects Module in the COSYMA Package (invited paper)

    The accuracy of models that are used to calculate the risk from early health effects due to exposure to a large dose of radiation from radioactive materials has been investigated. Early health effects are radiation diseases that occur within six weeks after the exposure. The present investigation provides data needed for subsequent analysis of the accuracy of estimates of the risks from nuclear power plant accidents (accident consequence assessments). By means of a formal expert elicitation procedure, for a limited number of exposure cases, a set of data has been obtained that quantifies the accuracy of risk estimates for early health effects. These data have been implemented in the generic models for calculating the risk and the accuracy of the calculated risk. These generic models are currently applied in accident consequence assessments. (author)

  19. Accidents, probabilities and consequences

    Following brief discussion of the safety of wind-driven power plants and solar power plants, some aspects of the safety of fast breeder and thermonuclear power plants are presented. It is pointed out that no safety evaluation of breeders comparable to the Rasmussen investigation has been carried out and that discussion of the safety aspects of thermonuclear power is only just begun. Finally, as an illustration of the varying interpretations of risk and safety analyses, four examples are given of predicted probabilities and consequences in Copenhagen of the maximum credible accident at the Barsebaeck plant, under the most unfavourable meterological conditions. These are made by the Environment Commission, Risoe Research Establishment, REO (a pro-nuclear group) and OOA (an anti-nuclear group), and vary by a factor of over 1000. (JIW)

  20. Probabilistic Accident Consequence Uncertainty Analysis of the Atmospheric Dispersion and Deposition Module in the COSYMA Package (invited paper)

    The uncertainty analysis is described of the atmospheric dispersion and deposition module of COSYMA, describing both the methods of obtaining distributions on the input parameters and the results of the analysis. The uncertainty distributions on the input parameter values were obtained using formal techniques of expert judgement elicitation. The aim of the module analysis was to identify those parameters whose uncertainty makes major contributions to the overall uncertainty, and which should be included in the final analysis of the whole COSYMA system. (author)

  1. Probabilistic Accident Consequence Uncertainty Analysis of the Late Health Effects Module in the COSYMA Package (invited paper)

    The uncertainty analysis is described of the late health effects module of COSYMA, describing both the methods of obtaining distributions on the input parameters and the results of the analysis. The uncertainty distributions on the input parameter values were obtained using formal expert judgement elicitation techniques. The aim of the module analysis was to identify those parameters whose uncertainty makes major contributions to the overall uncertainty, and which should be included in the final analysis of the whole COSYMA package. (author)

  2. Accident consequence assessment code development

    This paper describes the new computer code system, OSCAAR developed for off-site consequence assessment of a potential nuclear accident. OSCAAR consists of several modules which have modeling capabilities in atmospheric transport, foodchain transport, dosimetry, emergency response and radiological health effects. The major modules of the consequence assessment code are described, highlighting the validation and verification of the models. (author)

  3. Consequences of the Chernobyl accident

    The techniques currently used in off-site consequence modelling are applied to the Chernobyl accident. Firstly, the time dependent spread of radioactive material across the European continent is considered, followed by a preliminary assessment of the dosimetric impact (in terms of collective and mean individual doses) on the various countries of Eastern and Western Europe. The consequences of the accident in the USSR are also discussed. Finally, the likely implications of the Chernobyl event on research in the field of environmental consequence assessment are outlined. (author)

  4. Health consequences [of the Chernobyl accident

    The World Health Organisation Conference on the Health Consequences of the Chernobyl and Other Radiological Accidents, held in Geneva last November, is reported. The lack of representation from the civil nuclear industry led often to one-sided debates instigated by the anti-nuclear lobbies present. Thyroid cancer in children as a result of the Chernobyl accident received particular attention. In Belarus, 400 cases have been noted, 220 in Ukraine and 60 in the Russian Federation. All have been treated with a high degree of success. The incidence of this cancer would be expected to follow the fallout path as the main exposure route was ingestion of contaminated foods and milk products. It was noted that the only way to confirm causality was if those children born since the accident failed to show the same increased incidence. Explanations were offered for the particular susceptibility of children to thyroid cancer following exposure to radiation. Another significant cause of concern was the health consequences to clean-up workers in radiological accidents. The main factor is psychological problems from the stress of knowing that they have received high radiation doses. A dramatic increase in psychological disorders has occurred in the Ukraine over the past ten years and this is attributed to stress generated by the Chernobyl accident, compounded by the inadequacy of the public advice offered at the time and the socio-economic uncertainties accompanying the breakup of the former USSR. (UK)

  5. Medical consequences of radiation accidents

    Since 1945, more than 1.8 x 1021 Bq of artificial radionuclides have been released into the atmosphere. Approximately 2.04 x 1018B, i.e. approx. 0.11%, are the result of accidents at nuclear industrial facilities. This percentage is causing increased interest among researchers. This is due to the fact that in the wake of accidental release radionuclides become distributed unevenly across the Earth's surface, and the associated exposures, fluctuating from background level to several grays, an induce both stochastic and deterministic effects in the irradiated population. A comparative analysis of the medical consequences of the twentieth century's most serious nuclear events, namely the authorized dumping of high level radioactive waste into the river Techa in 1950, the explosion of a storage tank containing long lived radioactive waste in the Southern Urals in 1957, the fire at Sellafield in 1957 and the accident at the Chernobyl nuclear power plant in 1986, has shown that when timely countermeasures are taken, the worst immediate and delayed medical consequences of an accident can be avoided. The consequences that have since been ascertained are a brief rise in the mortality rate during the first five years, with a dose in excess of 500 mSv; an increase in the incidence of leukaemia, with an absolute risk of up to 1.1. x 10-4 man·years/Gy; and increased mortality among children with external radiation doses of up to 1000 mSv, and internal doses of 99-190 mSv on the bone surfaces of neonates or 170-600 mSv on the bone surfaces of the mother. There is reliable evidence that, with external gamma radiation doses in excess of 520 mSv, the mortality rate for all malignant tumorous increases by 45-58% compared with the control level. There is also a significant increase in thyroid cancer frequency four to ten years after the incorporation of iodine isotopes by children aged up to 7 years, including an accumulation period in the womb. (author). 12 refs, 7 tabs

  6. Processing Expert Judgements in Accident Consequence Modelling (invited paper)

    In performing uncertainty analysis a distribution on the code input parameters is required. The construction of the distribution on the code input parameters for the joint CEC/USNRC Accident Consequence Code Uncertainty Analysis using Expert Judgement is discussed. An example from the food chain module is used to illustrate the construction. Different mathematical techniques have been developed to transform the expert judgements into the required format. Finally, the effect of taking account of correlations in performing uncertainty analysis is investigated. (author)

  7. Psychiatric consequences of road traffic accidents.

    Mayou, R; Bryant, B.; Duthie, R

    1993-01-01

    OBJECTIVE--To determine the psychiatric consequences of being a road traffic accident victim. DESIGN--Follow up study of road accident victims for up to one year. SETTING--Emergency department of the John Radcliffe Hospital, Oxford. SUBJECTS--188 consecutive road accident victims aged 18-70 with multiple injuries (motorcycle or car) or whiplash neck injury, who had not been unconscious for more than 15 minutes, and who lived in the catchment area. MAIN OUTCOME MEASURES--Present state examinat...

  8. Consequences of the Chernobyl accident

    A collection of three papers about the fallout in Austria from the 1986 Chernobyl reactor accident is given: 1. An overview of the research projects in Austria; 2. On the transfer into and uptake by crops and animal fodder; 3. On the reduction of cesium concentration in food. 18 tabs., 21 figs., 69 refs

  9. Assessing economic consequences of radiation accidents

    This project reviewed the literature on the economic consequences of accidents to determine the availability of assessment methods and data and their applicability to the high-level radioactive waste (HLW) disposal system before closure; determined needs for expansion, revision, or adaptation of methods and data for modeling economic consequences of accidents of the scale projected for the disposal system; and gathered data that might be useful for the needed revisions. 8 refs., 1 tab

  10. Chernobylsk accident (Causes and Consequences)- Part 2

    The causes and consequences of the nuclear accident at Chernobylsk-4 reactor are shortly described. The informations were provided by Russian during the specialist meeting, carried out at seat of IAEA. The Russian nuclear panorama; the site, nuclear power plant characteristics and sequence of events; the immediate measurements after accident; monitoring/radioactive releases; environmental contamination and ecological consequences; measurements of emergency; recommendations to increase the nuclear safety; and recommendations of work groups, are presented. (M.C.K.)

  11. Medical consequences of Chernobyl accident

    Galstyan I.A.

    2015-12-01

    Full Text Available Aim: to study the long-term effects of acute radiation syndrome (ARS, developed at the victims of the Chernobyl accident. Material and Methods. 237 people were exposed during the accident, 134 of them were diagnosed with ARS. Dynamic observation implies a thorough annual examination in a hospital. Results. In the first 1.5-2 years after the ARS mean group indices of peripheral blood have returned to normal. However, many patients had transient expressed moderate cytopenias. Granulocytopenia, thrombocytopenia, lymphopenia and erythropenia were the most frequently observed things during the first 5 years after the accident. After 5 years their occurences lowered. In 11 patients the radiation cataract was detected. A threshold dose for its development is a dose of 3.2 Gy Long-term effects of local radiation lesions (LRL range from mild skin figure smoothing to a distinct fibrous scarring, contractures, persistently recurrent late radiation ulcers. During all years of observation we found 8 solid tumors, including 2 thyroid cancers. 5 hematologic diseases were found. During 29 years 26 ARS survivors died of various causes. Conclusion. The health of ones with long-term ARS effects is determined by the evolution of the LRL effects on skin, radiation cataracts, hema-tological diseases and the accession of of various somatic diseases, not caused by radiation.

  12. The Chernobyl nuclear accident and its consequences

    An AAEC Task Group was set up shortly after the accident at the Chernobyl Nuclear Power Plant to monitor and evaluate initial reports and to assess the implications for Australia. The Task Group issued a preliminary report on 9 May 1986. On 25-29 August 1986, the USSR released details of the accident and its consequences and further information has become available from the Nuclear Energy Agency of OECD and the World Health Organisation. The Task Group now presents a revised report summarising this information and commenting on the consequences from the Australian viewpoint

  13. Health consequences of nuclear accidents

    The author first outlines that no exposure of mankind to environmental risks has been as exhaustively and continuously studied as that resulting from ionizing radiations. Apart from lethal effects, he describes non lethal cell lesions which are induced in tissues: mutations and modifications of gene expressions, either directly under the effect of radiation, or by water hydrolysis, or indirectly through a biochemical response to these initial events. Then, the author evokes the controversy about Chernobyl: according to scientists, there is no relationship between the health degradation (human morbidity and mortality) and fallouts whereas activist groups state that there is. The author then evokes that the WHO and the IAEA were accused to lie about the issue of victims and health consequences. He outlines that UNSCEAR reports are a reference for radio-biologists, and that the 2011 report confirmed the conclusions of the 2006 report. He comments some published data, notably those on the acute irradiation syndrome (ARS), on carcinogenic effects (essentially thyroid cancers for children, as there is no clear nor admitted relationship for other forms of cancer), on other pathologies. Finally, the author briefly discusses the issue of crisis management, the information about Fukushima, and the issue of Chernobyl fallouts in France

  14. Biological and medical consequences of nuclear accidents

    The study of the medical and biological consequences of the nuclear accidents is a vast program. The Chernobyl accident has caused some thirty deceases: Some of them were rapid and the others occurred after a certain time. The particularity of these deaths was that the irradiation has been associated to burns and traumatisms. The lesson learnt from the Chernobyl accident is to treat the burn and the traumatism before treating the irradiation. Contrary to what the research workers believe, the first wave of deaths has passed between 15 and 35 days and it has not been followed by any others. But the therapeutic lesson drawn from the accident confirm the research workers results; for example: the radioactive doses band that determines where the therapy could be efficacious or not. the medical cares dispensed to the irradiated people in the hospital of Moscow has confirmed that the biochemical equilibrium of proteinic elements of blood has to be maintained, and the transfusion of the purified elements are very important to restore a patient to health, and the sterilization of the medium (room, food, bedding,etc...) of the patient is indispensable. Therefore, it is necessary to establish an international cooperation for providing enough sterilized rooms and specialists in the irradiation treatment. The genetic consequences and cancers from the Chernobyl accident have been discussed. It is impossible to detect these consequences because of their negligible percentages. (author)

  15. Radiological consequences of the Chernobyl reactor accident

    The reactor accident at unit 4 of the Chernobyl nuclear power plant in Ukraine has deeply affected the living conditions of millions of people. Especially the health consequences have been of public concern up to the present and also been the subject of sometimes absurd claims. The current knowledge on the radiological consequences of the accident is reviewed. Though an increased hazard for some risk groups with high radiation exposure, e.g., liquidators, still cannot be totally excluded for the future, the majority of the population shows no statistically significant indication of radiation-induced illnesses. The contribution of the Research Center Juelich to the assessment of the post-accidental situation and psychological relief of the population is reported. The population groups still requiring special attention include, in particular, children growing up in highly contaminated regions and the liquidators of the years 1986 and 1987 deployed immediately after the accident. (author)

  16. Assessment of off-site consequences of nuclear accidents (MARIA)

    A brief report is given of a workshop held in Luxembourg in 1985 on methods for assessing the off-site radiological consequences of nuclear accidents (MARIA). The sessions included topics such as atmospheric dispersion; foodchain transfer; urban contamination; demographic and land use data; dosimetry, health effects, economic and countermeasures models; uncertainty analysis; and application of probabilistic risk assessment results as input to decision aids. (U.K.)

  17. Consequences in Sweden of the Chernobyl accident

    It summarizes the consequences in Sweden of the Chernobyl accident, describes the emergency response, the basis for decisions and countermeasures, the measurement strategies, the activity levels and doses and countermeasures and action levels used. Past and remaining problems are discussed and the major investigations and improvements are given. (author)

  18. Consequences in Guatemala of the Chernobyl accident

    Because of the long distance between Guatemala and Chernobyl, the country did not undergo direct consequences of radioactive contamination in the short term. However, the accident repercussions were evident in the medium and long-term, mainly in two sectors, the economic-political and the environmental sectors

  19. Real and mythical consequences of Chernobyl accident

    This presentation describes the public Unacceptance of Nuclear Power as a consequence of Chernobyl Accident, an accident which was a severest event in the history of the nuclear industry. It was a shock for everybody, who has been involved in nuclear power programs. But nobody could expect that it was also the end romantic page in the nuclear story. The scale of the detriment was a great, and it could be compared with other big technological man-made catastrophes. But immediately after an accident mass media and news agencies started to transmit an information with a great exaggerations of the consequences of the event. In a report on the Seminar The lessons of the Chernobyl - 1' in 1996 examples of such incorrect information, were cited. Particularly, in the mass media it was declared that consequences of the accident could be compared with a results of the second world war, the number of victims were more than hundred thousand people, more than million of children have the serious health detriments. Such and other cases of the misconstruction have been called as myths. The real consequences of Chernobyl disaster have been summed on the International Conference 'One decade after Chernobyl' - 2, in April 1996. A very important result of the Chernobyl accident was a dissemination of stable unacceptance of the everything connected with 'the atom'. A mystic horror from invisible mortal radiation has been inspired in the masses. And from such public attitude the Nuclear Power Programs in many countries have changed dramatically. A new more pragmatic and more careful atomic era started with a slogan: 'Kernkraftwerk ? Nein, danke'. No doubt, a Chernobyl accident was a serious technical catastrophe in atomic industry. The scale of detriment is connected with a number of involved peoples, not with a number of real victims. In comparison with Bhopal case, earthquakes, crashes of the airplanes, floods, traffic accidents and other risky events of our life - the Chernobyl is

  20. The Chernobyl accident consequences; Consequences de l'accident de Tchernobyl

    NONE

    2001-04-01

    Five teen years later, Tchernobyl remains the symbol of the greater industrial nuclear accident. To take stock on this accident, this paper proposes a chronology of the events and presents the opinion of many international and national organizations. It provides also web sites references concerning the environmental and sanitary consequences of the Tchernobyl accident, the economic actions and propositions for the nuclear safety improvement in the East Europe. (A.L.B.)

  1. Consequences and problems of the Chernobyl accident

    The data on epidemic situation in connection with the Chernobyl accident, based on the personal medical and dosimetric information on all the persons, subjected to radiation effect, and included in the Russian state medicodosimetric register, are presented. The consequences of the Chernobyl accident become the cause for origination of serious radiation injures by 134 persons (with lethal outcome by 37 patients) and also remote radiation stochastic effects by children (thyroid gland cancer) and by liquidators (thyroid gland leucosis and cancer). The permanent stress and other unfavorable factors conditioned aggravation of chronical and increase in somatic diseases and psychoneurotic disorders

  2. Environmental consequences of releases from nuclear accidents

    The primary purpose of this report is to present the results of a four-year Nordic cooperation program in the area of consequence assessment of nuclear accidents with large releases to the environment. This program was completed in 1989. Related information from other research programs has also been described, so that many chapters of the report reflect the current status in the respective areas, in addition to containing the results of the Nordic program. (author) 179 refs

  3. Procedures Guide for Structural Expert Judgement in Accident Consequence Modelling (invited paper)

    A protocol is outlined for using structured expert judgement to generate uncertainty data for uncertainty analyses. The use of performance based weighting as an instrument to enable optimisation of the aggregated experts' assessments is emphasised. Examples are shown from the EC/USNRC joint study on Probabilistic Accident Consequence Uncertainty Analysis. (author)

  4. Radiological consequences of the Chernobyl reactor accident

    Fifty years of peaceful utilization of nuclear power were interrupted by the reactor accident in unit 4 of the Chernobyl nuclear power station in Ukraine in 1986, a disruptive event whose consequences profoundly affected the way of life of millions of people, and which has moved the public to this day. Releases of radioactive materials contaminated large areas of Belarus, the Russian Federation, and Ukraine. Early damage in the form of radiation syndrome was suffered by a group of rescue workers and members of the reactor operating crew, in some cases with fatal consequences, while the population does not, until now, show a statistically significant increase in the rate of late damage due to ionizing radiation expect for thyroid diseases in children. In particular, no increases in the rates of solid tumors, leukaemia, genetic defects, and congenital defects were detected. For some risk groups exposed to high radiation doses (such as liquidators) the hazard may still be greater, but the large majority of the population need not live in fear of serious impacts on health. Nevertheless, the accident shows major negative social and psychological consequences reinforced by the breakdown of the Soviet Union. This may be one reason for the observed higher incidence of other diseases whose association with the effects of radiation as a cause has not so far been proven. The measurement campaign conducted by the federal government in 1991-1993 addressed these very concerns of the public in an effort to provide unbiased information about exposures detected, on the one hand, in order to alleviate the fears of the public and reduce stress and, on the other hand, to contribute to the scientific evaluation of the radiological situation in the regions most highly exposed. The groups of the population requiring special attention in the future include especially children growing up in highly contaminated regions, and the liquidators of 1986 and 1987 employed in the period immediately

  5. The consequences of the Chernobyl reactor accident

    After the decay of the iodine isotopes the measuring campaigns, in addition to the measuring of soil pollution and pollution of products, concentrated on the way of the cesium isotopes through the food chain, especially in crops, milk, meat and mother's milk. A special programme was developed for the analysis of foreign basic substances for teas, essences and tinctures. In connection with the incorporation measurements in the university hospital Eppendorf the measurement campaigns provided the data material in order to calculate with the aid of the computer program ECOSYS of the GSF the effective dose equivalent which the inhabitants of Hamburg additionally take up due to the accident of Chernobyl. Consequences with regard to measuring methods and social consequences are mentioned. (DG)

  6. Assessment methods and minimization of radiological consequences of nuclear accidents

    The uncertainty and sensitivity analyses with the program system COSYMA for assessing the radiological consequences of nuclear accidents, performed since 1997 in close co-operation with the University of Delft, NL, and the NRPB, UK, have been terminated and fully documented. Work on the real-time on-line decision support system RODOS for off-site emergency management after nuclear accidents has concentrated on the preparation of the operational version PV 4.0; it will be released by mid 2000. It has been developed and customised to the various regions of Europe in close co-operation with some 40 contract partners in East and West Europe. The operational use of the RODOS system at a central place in Germany and in emergency centres of other West and East European countries is in progress. (orig.)

  7. Cosyma a new programme package for accident consequence assessment

    This report gives details of a new programme package for accident consequence assessment, prepared under the CEC's Maria programme (Methods for assessing the radiological impact of accidents) initiated in 1982 to review and build on the nuclear accident consequence assessment methods in use within the European Community

  8. A general approach to critical infrastructure accident consequences analysis

    Bogalecka, Magda; Kołowrocki, Krzysztof; Soszyńska-Budny, Joanna

    2016-06-01

    The probabilistic general model of critical infrastructure accident consequences including the process of the models of initiating events generated by its accident, the process of environment threats and the process of environment degradation is presented.

  9. Environmental consequences of releases from nuclear accidents

    The report presents the results of a four-year Nordic cooperation project (AKTU-200). The results have impact upon many facets of accident consequence assessment, ranging from new computational tools to recommendations concerning food preparation methods to be utilized in a fallout situation. Some of the subprojects have approached areas where little or no research has been performed previously, like the project on winter conditions, the project on the physico/chemical form of radionuclides in the Chernobyl fallout, and the project on resuspension. The conclusion from the first of these projects is that the impact of an accident or fallout situation occuring during winter may be considerable smaller than in a similar situation during summer conditions. The most important conclusion from the second of these projects is that bioavailability of radiocesium in soil is significantly lower than that of radiocesium in plant material taken up via the roots. In the third project is was found that the resuspension factor is several orders of magnitude lower than the values traditionally cited, and that resuspension is a local phenomenon in a majority of weather conditions. The development of large-scale testing of mitigating actions to prevent uptake of radiocesium in animals in a fallout situation is also one of the projects where new ground has been sucessfully broken. 189 refs., 89 figs., 55 tabs

  10. Chernobylsk accident (Causes and Consequences)-Part 1

    Facts, project data, hypothesis, calculations, evaluations, monitoring, standard requirements and several considerations, related to causes, effects and consequences of Chernobylsk-4 accident. (M.C.K.)

  11. Cost per severe accident as an index for severe accident consequence assessment and its applications

    The Fukushima Accident emphasizes the need to integrate the assessments of health effects, economic impacts, social impacts and environmental impacts, in order to perform a comprehensive consequence assessment of severe accidents in nuclear power plants. “Cost per severe accident” is introduced as an index for that purpose. The calculation methodology, including the consequence analysis using level 3 probabilistic risk assessment code OSCAAR and the calculation method of the cost per severe accident, is proposed. This methodology was applied to a virtual 1,100 MWe boiling water reactor. The breakdown of the cost per severe accident was provided. The radiation effect cost, the relocation cost and the decontamination cost were the three largest components. Sensitivity analyses were carried out, and parameters sensitive to cost per severe accident were specified. The cost per severe accident was compared with the amount of source terms, to demonstrate the performance of the cost per severe accident as an index to evaluate severe accident consequences. The ways to use the cost per severe accident for optimization of radiation protection countermeasures and for estimation of the effects of accident management strategies are discussed as its applications. - Highlights: • Cost per severe accident is used for severe accident consequence assessment. • Assessments of health, economic, social and environmental impacts are included. • Radiation effect, relocation and decontamination costs are important cost components. • Cost per severe accident can be used to optimize radiation protection measures. • Effects of accident management can be estimated using the cost per severe accident

  12. Consequences of the Fukushima accident: A preliminary assessment and discussion

    Tsunami due to the earthquake in East Japan Sea eventually leaded to a severe nuclear accident in Fukushima Dai-ichi nuclear power plant. This event immediately became the focus of the whole world. The work to roughly evaluate and predict the consequence of this nuclear accident is summarized in this paper and the work actually provides valuable information in predicting the scale and severity of the accident comparing to the published information on the accident thereafter. (authors)

  13. Medical consequences of a nuclear plant accident

    The report gives background information concerning radiation and the biological medical effects and damages caused by radiation. The report also discusses nuclear power plant accidents and efforts from the medical service in the case of a nuclear power plant accident. (L.F.)

  14. Uncertainty Principle Consequences at Thermal Equilibrium

    Pachon, Leonardo A; Zueco, David; Brumer, Paul

    2014-01-01

    Contrary to the conventional wisdom that deviations from standard thermodynamics originate from the strong coupling to the bath, it is shown that these deviations are intimately linked to the power spectrum of the thermal bath. Specifically, it is shown that the lower bound of the dispersion of the total energy of the system, imposed by the uncertainty principle, is dominated by the bath power spectrum and therefore, quantum mechanics inhibits the system thermal-equilibrium-state from being described by the canonical Boltzmann's distribution. This is in sharp contrast to the classical case, for which the thermal equilibrium distribution of a system interacting via central forces with pairwise-self-interacting environment, irrespective of the interaction strength, is shown to be \\emph{exactly} characterized by the canonical Boltzmann distribution. As a consequence of this analysis, we define an \\emph{effective coupling} to the environment that depends on all energy scales in the system and reservoir interactio...

  15. Informational uncertainties of risk assessment about accidents of chemicals

    2001-01-01

    An analysis system of informational uncertainties for accidental risk assessment of chemicals is introduced. Statistical test methods and fuzzy sets method can do the quantitative analysis of the input parameters. The uncertainties of the model can be used by quantitative compared method for the leakage accidents of chemicals. The estimation of the leaking time is important for discussing accidental source term. The uncertain analyses of the release accident for pipeline gas (CO) liquid chlorine and liquid propane gas (LPG) have been discussed.

  16. Fast detections of the accident. Radiological consequences

    This paper shows how the contamination due to the accident of Chernobylsk has been discovered in Sweden. The Swedish national Institute of radio-protection describes in detail the measurements done, and the decisions of radioprotection which have been taken

  17. The Chernobyl accident 20 years on: an assessment of the health consequences and the international response.

    Baverstock, Keith; Williams, Dillwyn

    2007-01-01

    Twenty years after the Chernobyl accident the WHO and the International Atomic Energy Authority issued a reassuring statement about the consequences. Our objectives in this study were to evaluate the health impact of the Chernobyl accident, assess the international response to the accident, and consider how to improve responses to future accidents. So far, radiation to the thyroid from radioisotopes of iodine has caused several thousand cases of thyroid cancer but very few deaths; exposed children were most susceptible. The focus on thyroid cancer has diverted attention from possible nonthyroid effects. The international response to the accident was inadequate and uncoordinated, and has been unjustifiably reassuring. Accurate assessment in future health effects is not currently possible in the light of dose uncertainties, current debates over radiation actions, and the lessons from the late consequences of atomic bomb exposure. Because of the uncertainties from and the consequences of the accident, it is essential that investigations of its effects should be broadened and supported for the long term. The United Nations should initiate an independent review of the actions and assignments of the agencies concerned, with recommendations for dealing with future international-scale accidents. These should involve independent scientists and ensure cooperation rather than rivalry. PMID:17680126

  18. Source term and radiological consequences of the Chernobyl accident

    This report presents the results of a study of the source term and radiological consequences of the Chernobyl accident. The results two parts. The first part was performed during the first 2 months following the accident and dealt with the evaluation of the source term and an estimate of individual doses in the European countries outside the Soviet Union. The second part was performed after August 25-29, 1986 when the Soviets presented in a IAEA Conference in Vienna detailed information about the accident, including source term and radiological consequences in the Soviet Union. The second part of the study reconfirms the source term evaluated in the first part and in addition deals with the radiological consequences in the Soviet Union. Source term and individual doses are calculated from measured post-accident data, reported by the Soviet Union and European countries, microcomputer program PEAR (Public Exposure from Accident Releases). 22 refs

  19. The consequences of the Chernobyl nuclear accident in Greece

    In this report the radioactive fallout on Greece from the Chernobyl nuclear accident is described. The flow pattern to Greece of the radioactive materials released, the measurements performed on environmental samples and samples of the food chain, as well as some estimations of the population doses and of the expected consequences of the accident are presented. The analysis has shown that the radiological impact of the accident in Greece can be considered minor. (J.K.)

  20. Consequences of the Chernobyl accident in Lithuania

    After the Chernobyl accident of 26 April, 1986, population dose assessment favours the view that the radiation risk of population effected by the early fallout would be different from that in regions contaminated later. Taking into account the short half-time of the most important radioactive iodine isotopes, thyroid disorders would be expected mainly to follow the early fallout distribution. At the time of accident at Unite 4 of the Chernobyl NPP, surface winds were from the Southeast. The initial explosions and heat carried volatile radioactive materials to the 1,5 km height, from where they were transported over the Western part of Belarus, Southern and Western part of Lithuania toward Scandinavian countries. Thus the volatile radioiodine and some other radionuclides were detected in Lithuania on the very first days after the accident. The main task of the work - to conduct short Half-time radioiodine and long half-time radiocesium dose assessment of Lithuanian inhabitants a result of the early Chernobyl accident fallout

  1. Severe Accident Progression and Consequence Assessment Methodology Upgrades in ISAAC for Wolsong CANDU6

    Amongst the applications of integrated severe accident analysis codes like ISAAC, the principal are to a) help develop an understanding of the severe accident progression and its consequences; b) support the design of mitigation measures by providing for them the state of the reactor following an accident; and c) to provide a training platform for accident management actions. After Fukushima accident there is an increased awareness of the need to implement effective and appropriate mitigation measures and empower the operators with training and understanding about severe accident progression and control opportunities. An updated code with reduced uncertainties can better serve these needs of the utility making decisions about mitigation measures and corrective actions. Optimal deployment of systems such as PARS and filtered containment venting require information on reactor transients for a number of critical parameters. Thus there is a greater consensus now for a demonstrated ability to perform accident progression and consequence assessment analyses with reduced uncertainties. Analyses must now provide source term transients that represent the best in available understanding and so meaningfully support mitigation measures. This requires removal of known simplifications and inclusion of all quantifiable and risk significant phenomena. Advances in understanding of CANDU6 severe accident progression reflected in the severe accident integrated code ROSHNI are being incorporated into ISAAC using CANDU specific component and system models developed and verified for Wolsong CANDU 6 reactors. A significant and comprehensive upgrade of core behavior models is being implemented in ISAAC to properly reflect the large variability amongst fuel channels in feeder geometry, fuel thermal powers and burnup. The paper summarizes the models that have been added and provides some results to illustrate code capabilities. ISAAC is being updated to meet the current requirements and

  2. Method for consequence calculations for severe accidents

    This report was commissioned by the Swedish State Power Board. The report contains a calculation of radiation doses in the surroundings caused by a theoretical core meltdown accident at Ringhals reactor No 3/4. The accident sequence chosen for the calcualtions was a release caused by total power failure. The calculations were made by means of the PLUCON4 code. A decontamination factor of 500 is used to account for the scrubber effect. Meteorological data for two years from the Ringhals meteorological tower were analysed to find representative weather situations. As typical weather, Pasquill D, was chosen with a wind speed of 10 m/s, and as extreme weather, Pasquill E, with a wind speed of 2 m/s. 19 refs. (author)

  3. Medical demographic consequences of the Chernobyl accident

    A demographic study was made of the population evacuated from the 30-km zone around the nuclear power plant and of the population living in areas over which the radioactive cloud passed and over which the plume was formed. For the farmers evacuated from 11,655 homes in the Chernobyl region, 7,000 new houses, built in the Kiev region, had already been provided within 5 months of the accident, and by the summer of 1987 another 5,000 houses were available. A study of the resettlement of the population carried out a year after the accident showed that more than 60% of those evacuated continued to live in the regions from which the evacuation had taken place; about 5% were resettled in other republics, and 20% within their own republic. (author). 7 figs, 2 tabs

  4. Appearing consequences of the Chernobyl accident

    Full text: Chernobyl is the greatest world's tragedy after Chirosima. Global results of this tragedy is already being seen. They are the people who have received radiation dose. the first type of cancer 5 years after Chernobyl accident was the thyroid gland cancer, the reason of it, large quantities of radioactive iodine in the air, food products, milk of cattle and finally their collection in the thyroid gland cancer entering the human body. Period all of a sudden after 10 years completed the next latent type of cancer was leykoz. Giving rise to this type of cancer more sensitive to radiation of the body - a violation of the spinal brain function. After 20 years passing from the accident in the first generation one ill child must be born cause of undergoing to radiation father or mother from each three days in Belarus, Russia and Ukraine

  5. Estimation of cost per severe accident for improvement of accident protection and consequence mitigation strategies

    To assess the complex situations regarding the severe accidents such as what observed in Fukushima Accident, not only radiation protection aspects but also relevant aspects: health, environmental, economic and societal aspects; must be all included into the consequence assessment. In this study, the authors introduce the “cost per severe accident” as an index to analyze the consequences of severe accidents comprehensively. The cost per severe accident consists of various costs and consequences converted into monetary values. For the purpose of improvement of the accident protection and consequence mitigation strategies, the costs needed to introduce the protective actions, and health and psychological consequences are included in the present study. The evaluations of these costs and consequences were made based on the systematic consequence analysis using level 2 and 3 probabilistic safety assessment (PSA) codes. The accident sequences used in this analysis were taken from the results of level 2 seismic PSA of a virtual 1,100 MWe BWR-5. The doses to the public and the number of people affected were calculated using the level 3 PSA code OSCAAR of Japan Atomic Energy Agency (JAEA). The calculations have been made for 248 meteorological sequences, and the outputs are given as expectation values for various meteorological conditions. Using these outputs, the cost per severe accident is calculated based on the open documents on the Fukushima Accident regarding the cost of protective actions and compensations for psychological harms. Finally, optimized accident protection and consequence mitigation strategies are recommended taking into account the various aspects comprehensively using the cost per severe accident. The authors must emphasize that the aim is not to estimate the accident cost itself but to extend the scope of “risk-informed decision making” for continuous safety improvements of nuclear energy. (author)

  6. Information on economic and social consequences of the Chernobyl accident

    This ''Information on economic and social consequences of the Chernobyl accident'' was presented to the July 1990 session of the Economic and Social Council of the United Nations by the delegations of the Union of Soviet Socialist Republics, the Byelorussian Soviet Socialist Republic and the Ukrainian Soviet Socialist Republic. It presents the radiation situation, the medical aspects of the accident, the evacuation of the inhabitants from areas affected by radioactive contamination and their social welfare, the agro-industrial production and forestry in these areas, the decontamination operations, the scientific back-up for the work dealing with the consequences of the accident and the expenditure and losses resulting from the Chernobyl disaster

  7. Cassini Spacecraft Uncertainty Analysis Data and Methodology Review and Update/Volume 1: Updated Parameter Uncertainty Models for the Consequence Analysis

    WHEELER, TIMOTHY A.; WYSS, GREGORY D.; HARPER, FREDERICK T.

    2000-11-01

    Uncertainty distributions for specific parameters of the Cassini General Purpose Heat Source Radioisotope Thermoelectric Generator (GPHS-RTG) Final Safety Analysis Report consequence risk analysis were revised and updated. The revisions and updates were done for all consequence parameters for which relevant information exists from the joint project on Probabilistic Accident Consequence Uncertainty Analysis by the United States Nuclear Regulatory Commission and the Commission of European Communities.

  8. Thyroid consequences of the Chernobyl nuclear accident.

    Pacini, F; Vorontsova, T; Molinaro, E; Shavrova, E; Agate, L; Kuchinskaya, E; Elisei, R; Demidchik, E P; Pinchera, A

    1999-12-01

    It is well recognized that the use of external irradiation of the head and neck to treat patients with various non-thyroid disorders increases their risk of developing papillary thyroid carcinoma years after radiation exposure. An increased risk of thyroid cancer has also been reported in survivors of the atomic bombs in Japan, as well as in Marshall Island residents exposed to radiation during the testing of hydrogen bombs. More recently, exposure to radioactive fallout as a result of the Chernobyl nuclear reactor accident has clearly caused an enormous increase in the incidence of childhood thyroid carcinoma in Belarus, Ukraine, and, to a lesser extent, in the Russian Federation, starting in 1990. When clinical and epidemiological features of thyroid carcinomas diagnosed in Belarus after the Chernobyl accident are compared with those of naturally occurring thyroid carcinomas in patients of the same age group in Italy and France, it becomes apparent that the post-Chernobyl thyroid carcinomas were much less influenced by gender, virtually always papillary (solid and follicular variants), more aggressive at presentation and more frequently associated with thyroid autoimmunity. Gene mutations involving the RET proto-oncogene, and less frequently TRK, have been shown to be causative events specific for papillary cancer. RET activation was found in nearly 70% of the patients who developed papillary thyroid carcinomas following the Chernobyl accident. In addition to thyroid cancer, radiation-induced thyroid diseases include benign thyroid nodules, hypothyroidism and autoimmune thyroiditis, with or without thyroid insufficiency, as observed in populations after environmental exposure to radioisotopes of iodine and in the survivors of atomic bomb explosions. On this basis, the authors evaluated thyroid autoimmune phenomena in normal children exposed to radiation after the Chernobyl accident. The results demonstrated an increased prevalence of circulating thyroid

  9. Radiological attacks and accidents. Medical consequences

    Probability of the occurrence of radiological attacks appears to be elevated after the terrorist attacks against the United States on September 11 in 2001. There are a lot of scenarios of radiological attack: simple radiological device, radiological disperse device (RDD or dirty bomb), attacks against nuclear reactor, improvised nuclear device, and nuclear weapons. Of these, RDD attack is the most probable scenario, because it can be easily made and can generate enormous psychological and economic damages. Radiological incidents are occurring to and fro in the world, including several cases of theft to nuclear facilities and unsuccessful terrorist attacks against them. Recently, a former Russian spy has allegedly been killed using polonium-210. In addition, serious radiological accidents have occurred in Chernobyl, Goiania, and Tokai-mura. Planning, preparation, education, and training exercise appear to be essential factors to cope with radiological attacks and accidents effectively without feeling much anxiety. Triage and psychological first aid are prerequisite to manage and provide effective medial care for mass casualties without inducing panic. (author)

  10. Method for consequence calculations for severe accidents

    This report was commissioned by the Swedish State Power Board. The report contains a calculation of radiation doses in the surroundings caused by a theoretical core meltdown accident at Forsmark reactor No 3. The assumption used for the calculations were a 0.06% release of iodine and cesium corresponding to a 0.1% release through the FILTRA plant at Barsebaeck. The calculations were made by means of the PLUCON4 code. Meteorological data for two years from the Forsmark meteorological tower were analysed to find representative weather situations. As typical weather pasquill D was chosen with wind speed 5 m/s, and as extreme weather, Pasquill F with wind speed 2 m/s. 23 tabs., 36 ills., 21 refs. (author)

  11. Consequence of potential accidents in heavy water plants

    Heavy water plants realize the primary isotopic concentrations of water using H2O-H2S chemical exchange and they are chemical plants. As these plants are handling and spreading large quantities of hydrogen sulphide (high toxic, corrosive, flammable and explosive as) maintained in the process at relative high temperatures and pressures, it is required an assessing of risks associated with the potential accidents. The H2S released in atmosphere as a result of an accident will have negative consequences to property, population and environment. This paper presents a model of consequences quantitative assessment and its outcome for the most dangerous accident in heavy water plants. Several states of the art risk based methods were modified and linked together to form a proper model for this analyse. Five basic steps to identify the risks involved in operating the plants are followed: hazard identification, accident sequence development, H2S emissions calculus, dispersion analyses and consequences determination. A brief description of each step and some information of analysis results are provided. The accident proportions, the atmospheric conditions and the population density in the respective area were accounted for consequences calculus. The specific results of the consequences analysis allow to develop the plant's operating safety requirements so that the risk remain at an acceptable level. (authors)

  12. Offsite Radiological Consequence Analysis for the Bounding Flammable Gas Accident

    Carro, C A

    2003-01-01

    This document quantifies the offsite radiological consequences of the bounding flammable gas accident for comparison with the 25 rem Evaluation Guideline established in DOE-STD-3009, Appendix A. The bounding flammable gas accident is a detonation in a single-shell tank The calculation applies reasonably conservation input parameters in accordance with DOE-STD-3009, Appendix A, guidance. Revision 1 incorporates comments received from Office of River Protection.

  13. MELCOR Accident Consequence Code System (MACCS)

    This report describes the MACCS computer code. The purpose of this code is to simulate the impact of severe accidents at nuclear power plants on the surrounding environment. MACCS has been developed for the US Nuclear Regulatory Commission to replace the previous CRAC2 code, and it incorporates many improvements in modeling flexibility in comparison to CRAC2. The principal phenomena considered in MACCS are atmospheric transport, mitigative actions based on dose projection, dose accumulation by a number of pathways including food and water ingestion, early and latent health effects, and economic costs. The MACCS code can be used for a variety of applications. These include (1) probabilistic risk assessment (PRA) of nuclear power plants and other nuclear facilities, (2) sensitivity studies to gain a better understanding of the parameters important to PRA, and (3) cost-benefit analysis. This report is composed of three volumes. This document, Volume 1, the Users's Guide, describes the input data requirements of the MACCS code and provides directions for its use as illustrated by three sample problems

  14. MELCOR Accident Consequence Code System (MACCS)

    Chanin, D.I. (Technadyne Engineering Consultants, Inc., Albuquerque, NM (USA)); Sprung, J.L.; Ritchie, L.T.; Jow, Hong-Nian (Sandia National Labs., Albuquerque, NM (USA))

    1990-02-01

    This report describes the MACCS computer code. The purpose of this code is to simulate the impact of severe accidents at nuclear power plants on the surrounding environment. MACCS has been developed for the US Nuclear Regulatory Commission to replace the previous CRAC2 code, and it incorporates many improvements in modeling flexibility in comparison to CRAC2. The principal phenomena considered in MACCS are atmospheric transport, mitigative actions based on dose projection, dose accumulation by a number of pathways including food and water ingestion, early and latent health effects, and economic costs. The MACCS code can be used for a variety of applications. These include (1) probabilistic risk assessment (PRA) of nuclear power plants and other nuclear facilities, (2) sensitivity studies to gain a better understanding of the parameters important to PRA, and (3) cost-benefit analysis. This report is composed of three volumes. This document, Volume 1, the Users's Guide, describes the input data requirements of the MACCS code and provides directions for its use as illustrated by three sample problems.

  15. Consequences of the Chernobyl accident in Styria

    We present results which document the contamination of Styria (Southern part of Austria) immediately after and in the years following the Chernobyl accident. The radioactivity and distribution of radionuclides in aerosols, rain water, soil, vegetation, animals and various samples of food are described in great detail. One of the key results is that the highest levels of contamination were found in two districts (Liezen, Deutschlandsberg), and the deposition rates for Cs-137 were determined to be in the range from 3 to about 80 kBq/m2. Of particular interest are studies concerning the migration and distribution of radionuclides in soil, the uptake of radiocesium by the aquatic vegetation and the existence of radionuclides in the natural ecosystem up to this day. Effective dose equivalents due to incorporated radiocesium was estimated to be 252.2 μSv for the adult population of Graz (capital of Styria) over the four years follwing the fallout. (authors) 17 papers are presented and are of INIS scope

  16. MELCOR Accident Consequence Code System (MACCS)

    This report describes the MACCS computer code. The purpose of this code is to simulate the impact of severe accidents at nuclear power plants on the surrounding environment. MACCS has been developed for the US Nuclear Regulatory Commission to replace the previously used CRAC2 code, and it incorporates many improvements in modeling flexibility in comparison to CRAC2. The principal phenomena considered in MACCS are atmospheric transport, mitigative actions based on dose projections, dose accumulation by a number of pathways including food and water ingestion, early and latent health effects, and economic costs. The MACCS code can be used for a variety of applications. These include (1) probabilistic risk assessment (PRA) of nuclear power plants and other nuclear facilities, (2) sensitivity studies to gain a better understanding of the parameters important to PRA, and (3) cost-benefit analysis. This report is composed of three volumes. Volume I, the User's Guide, describes the input data requirements of the MACCS code and provides directions for its use as illustrated by three sample problems. Volume II, the Model Description, describes the underlying models that are implemented in the code, and Volume III, the Programmer's Reference Manual, describes the code's structure and database management

  17. MELCOR Accident Consequence Code System (MACCS)

    This report describes the MACCS computer code. The purpose of this code is to simulate the impact of severe accidents at nuclear power plants on the surrounding environment. MACCS has been developed for the US Nuclear Regulatory Commission to replace the previously used CRAC2 code, and it incorporates many improvements in modeling flexibility in comparison to CRAC2. The principal phenomena considered in MACCS are atmospheric transport, mitigative actions based on dose projection, dose accumulation by a number of pathways including food and water ingestion, early and latent health effects, and economic costs. The MACCS code can be used for a variety of applications. These include (1) probabilistic risk assessment (PRA) of nuclear power plants and other nuclear facilities, (2) sensitivity studies to gain a better understanding of the parameters important to PRA, and (3) cost-benefit analysis. This report is composed of three volumes. Volume I, the User's Guide, describes the input data requirements of the MACCS code and provides directions for its use as illustrated by three sample problems. Volume II, the Model Description, describes the underlying models that are implemented in the code, and Volume III, the Programmer's Reference Manual, describes the code's structure and database management. 59 refs., 14 figs., 15 tabs

  18. MELCOR Accident Consequence Code System (MACCS)

    Jow, H.N.; Sprung, J.L.; Ritchie, L.T. (Sandia National Labs., Albuquerque, NM (USA)); Rollstin, J.A. (GRAM, Inc., Albuquerque, NM (USA)); Chanin, D.I. (Technadyne Engineering Consultants, Inc., Albuquerque, NM (USA))

    1990-02-01

    This report describes the MACCS computer code. The purpose of this code is to simulate the impact of severe accidents at nuclear power plants on the surrounding environment. MACCS has been developed for the US Nuclear Regulatory Commission to replace the previously used CRAC2 code, and it incorporates many improvements in modeling flexibility in comparison to CRAC2. The principal phenomena considered in MACCS are atmospheric transport, mitigative actions based on dose projection, dose accumulation by a number of pathways including food and water ingestion, early and latent health effects, and economic costs. The MACCS code can be used for a variety of applications. These include (1) probabilistic risk assessment (PRA) of nuclear power plants and other nuclear facilities, (2) sensitivity studies to gain a better understanding of the parameters important to PRA, and (3) cost-benefit analysis. This report is composed of three volumes. Volume I, the User's Guide, describes the input data requirements of the MACCS code and provides directions for its use as illustrated by three sample problems. Volume II, the Model Description, describes the underlying models that are implemented in the code, and Volume III, the Programmer's Reference Manual, describes the code's structure and database management. 59 refs., 14 figs., 15 tabs.

  19. Radioecological and dosimetric consequences of Chernobyl accident in France

    After ten years and the taking in account of numerous data, it can be affirmed that the dosimetric consequences of Chernobyl accident will have been limited in France. for the period 1986-2046, the individual middle efficient dose commitment, for the area the most reached by depositing is inferior to 1500 μSv, that represents about 1% of middle natural exposure in the same time. but mountains and forests can have more important surface activities than in plain. Everywhere else, it can be considered that the effects of Chernobyl accident are disappearing. the levels of cesium 137 are now often inferior to what they were before the accident. (N.C.)

  20. The Fukushima accident: radiological consequences and first lessons. Proceedings

    This document brings together the available presentations given at the conference organised by the French society of radiation protection about the Fukushima accident, its radiological consequences and the first lessons learnt. Sixteen presentations (slides) are compiled in this document and deal with: 1 - Accident progress and first actions (Thierry Charles, IRSN); 2 - Conditions and health monitoring of the Japanese intervention teams (Bernard Le Guen, EDF); 3 - The Intra Group action after the Fukushima accident (Michel Chevallier, Groupe Intra; Frederic Mariotte, CEA); 4 - Processing of effluents (Georges Pagis, Areva); 5 - Fukushima accident: impact on the terrestrial environment in Japan (Didier Champion, IRSN); 6 - Consequences of the Fukushima accident on the marine environment (Dominique Boust, IRSN); 7 - Territories decontamination perspectives (Pierre Chagvardieff, CEA); 8 - Actions undertaken by Japanese authorities (Florence Gallay, ASN); 9 - Japanese population monitoring and health stakes (Philippe Pirard, InVS); 10 - Citizen oversight actions implemented in Japan (David Boilley, ACRO); 11 - Implementation of ICRP's (International Commission on Radiological Protection) recommendations by Japanese authorities: first analysis (Jacques Lochard, CIPR); 12 - Control of Japan imported food stuff (David Brouque, DGAL); 13 - Questions asked by populations in France and in Germany (Florence-Nathalie Sentuc, GRS; Pascale Monti, IRSN); 14 - Labour law applicable to French workers working abroad (Thierry Lahaye, DGT); 15 - Protection of French workers working in Japan, Areva's experience (Patrick Devin, Areva); 16 - Fukushima accident experience feedback and post-accident nuclear doctrine (Jean-Luc Godet, ASN)

  1. First international workshop on severe accidents and their consequences. [Chernobyl Accident

    1989-07-01

    An international workshop on past severe nuclear accidents and their consequences was held in Dagomys region of Sochi, USSR on October 30--November 3, 1989. The plan of this meeting was approved by the USSR Academy of Sciences and by the USSR State Committee of the Utilization of Atomic Energy. The meeting was held under the umbrella of the ANS-SNS agreement of cooperation. Topics covered include analysis of the Chernobyl accident, safety measures for RBMK type reactors and consequences of the Chernobyl accident including analysis of the ecological, genetic and psycho-social factors. Separate reports are processed separately for the data bases. (CBS)

  2. OFFSITE RADIOLOGICAL CONSEQUENCE ANALYSIS FOR THE BOUNDING FLAMMABLE GAS ACCIDENT

    This document quantifies the offsite radiological consequences of the bounding flammable gas accident for comparison with the 25 rem Evaluation Guideline established in DOE-STD-3009, Appendix A. The bounding flammable gas accident is a detonation in a SST. The calculation applies reasonably conservative input parameters in accordance with guidance in DOE-STD-3009, Appendix A. The purpose of this analysis is to calculate the offsite radiological consequence of the bounding flammable gas accident. DOE-STD-3009-94, ''Preparation Guide for US. Department of Energy Nonreactor Nuclear Facility Documented Safety Analyses'', requires the formal quantification of a limited subset of accidents representing a complete set of bounding conditions. The results of these analyses are then evaluated to determine if they challenge the DOE-STD-3009-94, Appendix A, ''Evaluation Guideline,'' of 25 rem total effective dose equivalent in order to identify and evaluate safety-class structures, systems, and components. The bounding flammable gas accident is a detonation in a single-shell tank (SST). A detonation versus a deflagration was selected for analysis because the faster flame speed of a detonation can potentially result in a larger release of respirable material. A detonation in an SST versus a double-shell tank (DST) was selected as the bounding accident because the estimated respirable release masses are the same and because the doses per unit quantity of waste inhaled are greater for SSTs than for DSTs. Appendix A contains a DST analysis for comparison purposes

  3. Joint CEC/OECD(NEA) workshop on recent advances in reactor accident consequence assessment

    The workshop on probabilistic accident consequence assessment techniques and their applications aims at a review of the present knowledge of all the work in this field. This includes the atmospheric dispersion and deposition modelling, with comparison of the different approaches, the exposure pathways with emphasis on post-deposition processes, the health effects with emphasis on the consequences of the Hiroshima and Nagasaki data re-evaluation, the countermeasures and their economic consequences, the uncertainty analysis of the models and finally the applications of these models as aids to decision making

  4. The Chernobyl reactor accident - provisional results and consequences

    Those involved at present in the analysis and estimation of consequences of the Chernobyl reactor accident are in a dilemma: While a worried and uncertain Western German public is calling for information the Soviet Union was practicing a rigorously restrictive information policy. Both the severity of the reactor accident and the complexity of events do urgently require the acquisition and evaluation of facts which will provide the basis for an objective factual discussion of issues and possible measures. The paper abstracted is trying to assess the alleged causes of the accident and estimate possible consequences. However, all attempts of that kind are based but on incomplete and dubious information as of May 21st, 1986. (orig.)

  5. Remote medical consequences of Chernobyl NPP accident in Armenia

    In result of global radio-ecological disaster at the Chernobyl NPP in Armenia there has appeared a great 'risk group' of persons, who had participated in liquidation of the accident consequences. The results of medical observation of this cohort carried out in dynamics in Scientific Center of Radiation Medicine and Burns during 25 years are brought in the work

  6. Hanford Waste Tank Bump Accident and Consequence Analysis

    BRATZEL, D.R.

    2000-06-20

    This report provides a new evaluation of the Hanford tank bump accident analysis and consequences for incorporation into the Authorization Basis. The analysis scope is for the safe storage of waste in its current configuration in single-shell and double-shell tanks.

  7. Hanford Waste Tank Bump Accident and Consequence Analysis

    This report provides a new evaluation of the Hanford tank bump accident analysis and consequences for incorporation into the Authorization Basis. The analysis scope is for the safe storage of waste in its current configuration in single-shell and double-shell tanks

  8. Radioecological and dosimetric consequences of the Chernobyl accident in France

    This study has as objective a survey of the radioecological and dosimetric consequences of the Chernobyl accident in France, as well as a prognosis for the years to come. It was requested by the Direction of Nuclear Installation Safety (DSIN) in relation to different organisms which effected measurements after this accident. It is based on the use of combined results of measurements and modelling by means of the code ASTRAL developed at IPSN. Various measurements obtained from five authorities and institutions, were made available, such as: activity of air and water, soil, processed food, agricultural and natural products. However, to achieve the survey still a modelling is needed. ASTRAL is a code for evaluating the ecological consequences of an accident. It allows establishing the correspondence between the soil Remnant Surface Activities (RSA, in Bq.m-2), the activity concentration of the agricultural production and the individual and collective doses resulting from external and internal exposures (due to inhalation and ingestion of contaminated nurture). The results of principal synthesis documents on the Chernobyl accident and its consequences were also used. The report is structured in nine sections, as follows: 1.Introduction; 2.Objective and methodology; 3.Characterization of radioactive depositions; 4;Remnant surface activities; 5.Contamination of agricultural products and foods; 6.Contamination of natural, semi-natural products and of drinking water; 7.Dosimetric evaluations; 8.Proposals for the environmental surveillance; 9.Conclusion. Finally, after ten years, one concludes that at present the dosimetric consequences of the Chernobyl accident in France were rather limited. For the period 1986-2046 the average individual effective dose estimated for the most struck zone is lower than 1500 μSv, which represents almost 1% of the average natural exposure for the same period. At present, the cesium 137 levels are at often inferior to those recorded before

  9. Consequences of Chernobyl accident in Europe

    ,000 'liquidators' ranged between 170 mSv in 1986 and 15 mSv in 1989. Among the >100,000 evacuees the average whole body dose prior to evacuation was 15 mSv. The average lifetime Chernobyl whole body doses in European countries outside the former Soviet Union range from 0.006 mSv in Portugal to 2.4 mSv in Bulgaria. In the Northern Hemisphere the average Chernobyl lifetime dose is 0.14 mSv, i.e. about 0.08% of the natural dose. The average global whole body dose of natural radiation during 70 years is about 170 mSv, and 700 mSv in typically high background areas. Epidemiological studies from Hiroshima and Nagasaki suggest that no increase in cancer mortality should be expected at a single whole body dose (in addition to natural background radiation) of <200 mSv, delivered during a fraction of a second. Doses of about 200 mSv accumulated over tens of years of exposure would be even less effective. Ten years after the Chernobyl catastrophe the total radiation death toll is 31 - 38 persons, among them 3 persons were the members of the public. The total expected number of thyroid cancer deaths is about 500. In Poland, a country closest to Chernobyl outside the former Soviet Union, during two days, starting on the second day after arrival of radioactive cloud, 18.5 million persons were administered a prophylactic dose of stable iodine in form of 'Lugol solution', to block the uptake of radioiodine by the thyroid. This caused a thyroid dose reduction by a factor of up to 5, without any intra-thyroid side effects. Economic loses related to necessary and unnecessary remedial measures are estimated to reach in Belarus between 1986 and 2015 US$ 191.7 billion, of which US$ 86.32 billion are costs of financial and other compensation ('privileges') for peoples living at contaminated regions. It is estimated that in Ukraine in regions where 'Chernobyl radiation dose' is less than 1 mSv/year about 1.73 million persons receives the 'privileges'. Psychosomatic consequences of radiophobia induced by

  10. Validation and verification of accident consequence assessment models

    Homma, T.; Togawa, O. [Japan Atomic Energy Research Inst., Tokyo (Japan); Takahashi, T. [Kyoto Univ., Kumatori, Osaka (Japan). Research Reactor Inst; Arkhipov, A.N. [Chernobyl Science and Technology Centre for International Research (Ukraine)

    2001-03-01

    An accident consequence assessment code, OSCAAR, primarily designed by Japan Atomic Energy Research Institute (JAERI) for use in probabilistic safety assessment (PSA) of nuclear reactors in Japan, was applied to use for siting, emergency planning, and development of design criteria, and in the comparative risk studies of different energy systems. After verifying the code system through the international code comparison organized by CEC and OECD/NEA, the validation and improvements of the individual models and the verification of the whole OSCAAR code system were made. The cooperative research between Chernobyl Science and Technology Center for International Research (CHESCIR) and JAERI provided a valuable opportunity to test the performance of the accident consequence assessment models by comparing the model predictions with data obtained in the Chernobyl accidents. The predictive capabilities of OSCAAR were demonstrated using the accident source term and meteorological data for estimating the early exposure to the public occurred during and shortly after plume passage. The calculations indicated that ground-shine dose and inhalation dose, particularly from large nonvolatile particulates were the main contributors in the early stage of the accident. (S. Ohno)

  11. The Fukushima accident and its consequences. Facts, explanations and comments

    This document proposes an overview of the present situation in the different reactors of the Fukushima power station and discusses its control by the operator. It also describes what went on, the causes of the accident, and what occurred on the accident day (earthquake, tsunami, flooding). It discusses whether some mistakes regarding the design and the protection of reactors could explain the accident. It presents the various measures which have been immediately implemented to protect the populations and to confine the accident. It proposes an assessment of damages for the ground and marine environment in terms of contamination. It addresses the consequences of the released radioactivity on population health and on personnel intervening within the site. It discusses the restoration perspectives for contaminated areas and the possible return of evacuated population. Then, it describes the different phases for the station dismantling. It evokes the issue of fallouts beyond Japan and in Europe, outlines some lessons learned from the accident and new safety measures to be implemented in France. It discusses how nuclear risk management is organised in France and its efficiency. It addresses the consequences for the development of nuclear energy in the world

  12. Reducing the consequences of reactor accidents with a green belt

    Considerable attention is being paid to reducing the consequences of low-probability accidents in nuclear power plants. A scheme based on the pollution absorption properties of trees is proposed to reduce early and continued mortalities among the general public due to an accident in a nuclear power plant. The consequences of a hypothetical case in which a large, cold, ground-level release of radionuclides into the atmosphere takes place have been analyzed in the absence and in the presence of a green belt (rows of trees). The results show that in the presence of a suitably designed green belt around a nuclear power plant, the consequences in terms of early and continued mortality as well as an interdiction area, involving relocation of population and supply of food stuff from an uncontaminated region, can be reduced by orders of magnitude. This could also help in substantially reducing the magnitude of emergency preparedness in the public domain

  13. A simplified model for calculating early offsite consequences from nuclear reactor accidents

    Madni, I.K.; Cazzoli, E.G.; Khatib-Rahbar, M.

    1988-07-01

    A personal computer-based model, SMART, has been developed that uses an integral approach for calculating early offsite consequences from nuclear reactor accidents. The solution procedure uses simplified meteorology and involves direct analytic integration of air concentration equations over time and position. This is different from the discretization approach currently used in the CRAC2 and MACCS codes. The SMART code is fast-running, thereby providing a valuable tool for sensitivity and uncertainty studies. The code was benchmarked against both MACCS version 1.4 and CRAC2. Results of benchmarking and detailed sensitivity/uncertainty analyses using SMART are presented. 34 refs., 21 figs., 24 tabs.

  14. Accident consequence calculations for project W-058 safety analysis

    This document describes the calculations performed to determine the accident consequences for the W-058 safety analysis. Project W-058 is the replacement cross site transfer system (RCSTS), which is designed to transort liquid waste between the 200 W and 200 E areas. Calculations for RCSTS safety analyses used the same methods as the calculations for the Tank Waste Remediation System (TWRS) Basis for Interim Operation (BIO) and its supporting calculation notes. Revised analyses were performed for the spray and pool leak accidents since the RCSTS flows and pressures differ from those assumed in the TWRS BIO. Revision 1 of the document incorporates review comments

  15. The Influence of Seasonal Characteristics on the Accident Consequences Analysis

    In order to examine the influence of seasonal characteristics on accident consequences, we defined a limited number of basic spectra based on the relative importance of source term release parameters and meteorological conditions on offsite health effects and economic impacts. We then investigated the variation in numbers and frequency of early health effects and economic impacts resulting from the severe accidents of the YGN 3 and 4 nuclear power plants from spectrum to spectrum by using MACCS code. These investigations were for meteorological conditions defined as typical on an annual basis. Also, we investigated the variation in numbers and frequency of early health effects and economic impacts for the same standard spectra for meteorological conditions defined as typical on a seasonal basis recognizing that there are four seasons with distinct meteorological characteristics. Results show that there are large differences in consequences from spectrum to spectrum, although an equal amount and mix of radioactive material is released to the atmosphere in each case. Therefore, release parameters and meteorological data have to be well characterized in order to estimate accident consequences resulting from an accident accurately. Also, there are large differences in the estimated number of health effects and economic impacts from season to season due to distinct seasonal variations in meteorological conditions in Korea. In fall, the early fatalities and early fatality risk show minimum values due to enhanced dispersion arising from increased atmospheric instability, and the early fatalities show maximum value in summer due to a large rainfall rate. On the contrast, the economic cost shows maximum value in fall and minimum in summer due to different atmospheric dispersion and rainfall rate. Therefore, it is necessary to consider seasonal characteristics in developing emergency response strategies for reducing offsite early health risks in the event of a severe

  16. Consequences and experiences - ten years after the Chernobyl accident

    On 26 April 1986. the most serious accident in the history of the nuclear industry occurred at the Chernobyl nuclear power plant in the former Soviet Union, near the present borders of Ukraine, Belarus and Russia.Material released into the atmosphere dispersed and eventually deposited back on the surface of the earth,were it was measurable over the whole northern hemisphere. Millions of people and all segments of life and economy have been affected by the accident. Radioactive contamination has reached several tens of MBq/m2 in the area of 30 km diameter around the reactor in 1986., and plants and animals have been exposed to short lived radionuclides up to external doses of several tens of Gy. In the early phase after the accident, 237 persons were suspected to have acute radiation syndrome as a consequence of the Chernobyl accident, but diagnoses has been confirmed in 134 cases. In that phase 28 person have died as a consequence of exposure. There are significant non - related health disorders and symptoms, such as anxiety, depression and various psychosomatic disorders attributable to mental stress among the population in the region

  17. Estimated consequences from severe spent nuclear fuel transportation accidents

    The RISKIND software package is used to estimate radiological consequences of severe accident scenarios involving the transportation of spent nuclear fuel. Radiological risks are estimated for both a collective population and a maximally exposed individual based on representative truck and rail cask designs described in the U.S. Nuclear Regulatory Commission (NRC) modal study. The estimate of collective population risk considers all possible environmental pathways, including acute and long-term exposures, and is presented in terms of the 50-y committed effective dose equivalent. Radiological risks to a maximally exposed individual from acute exposure are estimated and presented in terms of the first year and 50-y committed effective dose equivalent. Consequences are estimated for accidents occurring in rural and urban population areas. The modeled pathways include inhalation during initial passing of the radioactive cloud, external exposure from a reduction of the cask shielding, long-term external exposure. from ground deposition, and ingestion from contaminated food (rural only). The major pathways and contributing radionuclides are identified, and the effects of possible mitigative actions are discussed. The cask accident responses and the radionuclide release fractions are modeled as described in the NRC modal study. Estimates of severe accident probabilities are presented for both truck and rail modes of transport. The assumptions made in this study tend to be conservative; however, a set of multiplicative factors are identified that can be applied to estimate more realistic conditions

  18. Nuclear installations abroad the accident risks and their potential consequences

    This paper endeavors to assess the threat to Ireland from severe accidents at civil nuclear installations. Among the various types of nuclear installations worldwide, reactors and reprocessing plants are considered to be the most threatening and so the paper focuses on these. The threat is assumed to be a function of the risk of severe accidents at the above types of installations and the probability of unfavourable weather conditions carrying the radioactive releases to Ireland. Although nuclear installations designed in eastern Europe and Asia are less safe than others, the greatest threat to Ireland arises from nearby installations in the UK. The difficulty of measuring the probabilities and consequences of severe nuclear accidents at nuclear installations in general is explained. In the case of the UK installations, this difficulty is overcome to some degree by using values of 'tolerable' risk adopted by the national nuclear regulator to define the radiotoxic releases from nuclear accidents. These are used as input to atmospheric dispersion models in which unfavourable weather conditions for Ireland are assumed and radiation doses are calculated to members of the Irish public. No countermeasures, such as sheltering, are assumed. In the worst cast scenario no deaths would be expected in Ireland in the immediate aftermath of the accident however, an increase in cancers over a period of 25 years or so would be expected assuming present-day models for the effect of low level radiation are valid

  19. Consequences and effectiveness of relocation after nuclear accidents

    Extensive parameter studies have been performed with the program package COSYMA for probabilistic accident consequence assessments to quantify by means of PRA methods the interdependence of those quantities, which influence the extent, the duration, the efficiency and the monetary costs of relocation. As most important quantities, the amount of radionuclides released, the dose intervention levels for relocation, the (avoided) radiation doses in the population and the associated costs have been identified. Decontamination measures have also been included in the investigations, since they reduce the duration of relocation. The expression of all relevant accident consequences in monetary units allowed to investigate the applicability of cost/benefit analysis for deriving the most favourable intervention levels. It could be shown that weighting with different factors of collective doses calculated from different individual dose bands, and thus incorporating subjective judgements, significantly extends and improves the method. (orig./HP)

  20. Genetic consequences of the Chernobyl accident for Belarus republic

    various uncertainties. Only direct methods, which count the final effect, with all their drawbacks, can provide accurate information on genetic losses. We have estimated possible genetic consequences for the residents of Belarus Republic due to the Chernobyl accident by studying malformations found in legal medical abortuses and by counting congenital anomalies in fetuses and newborns. (J.P.N.)

  1. Health consequences of the Chernobyl accident: a review

    Full text of publication follows: on April 26, 1996, the accident at Chernobyl nuclear power plant led to the release into the atmosphere of considerable quantities of radionuclides. Most contaminated regions were in the southern Belarus, northern Ukraine and Bryansk and Kaluga regions of Russia. Main population groups exposed to the radioactivity released during the accident were the personnel at the Chernobyl plant and the rescue teams present on-site during the first hours, the cleanup workers (numbering about 600000) who participated in the decontamination and cleaning operations in the 30 km zone around the site, the residents of the same zone who were evacuated (numbering about 115000) and the inhabitants of contaminated zones (≥1 Ci/km2). Dose and dose rate levels as well as exposure pathways differ from one population group to another. A review of scientific articles published in the international literature till 1998 has been carried out. Apart the 28 deaths due to acute radiation sickness which occurred in the personnel of the plant and rescue teams within several days or weeks after the accident, two main public health consequences of the Chernobyl accident have been observed. First an unprecedented epidemic of thyroid cancers was detected in children first in 1992 in Belarus then in the Ukraine and to a lesser extent in Bryansk region. The spontaneous incidence of these tumours was multiplied by 100 in most contaminated regions. Although the role of the accident in this epidemic is now recognised, questions are raised regarding the respective role of radioactive agents and other environmental or genetic factors, and its evolution in the future. Regarding other kinds of solid cancers and leukemia, no excess has been clearly demonstrated in the residents of contaminated areas nor in liquidators. Second, results of available epidemiological investigations show an increased risk of psychological distress in residents of highly contaminated areas

  2. Tank Bump Accident Potential and Consequences During Waste Retrieval

    BRATZEL, D.R.

    2000-09-27

    This report provides an evaluation of Hanford tank bump accident potential and consequences during waste retrieval operations. The purpose of this report is to consider the best available new information to support recommendations for safety controls. A new tank bump accident analysis for safe storage (Epstein et al. 2000) is extended for this purpose. A tank bump is a postulated event in which gases, consisting mostly of water vapor, are suddenly emitted from the waste and cause tank headspace pressurization. Tank bump scenarios, physical models, and frequency and consequence methods are fully described in Epstein et al. (2000). The analysis scope is waste retrieval from double-shell tanks (DSTs) including operation of equipment such as mixer pumps and air lift circulators. The analysis considers physical mechanisms for tank bump to formulate criteria for bump potential during retrieval, application of the criteria to the DSTs, evaluation of bump frequency, and consequence analysis of a bump. The result of the consequence analysis is the mass of waste released from tanks; radiological dose is calculated using standard methods (Cowley et al. 2000).

  3. Evaluation of severe accident risks: Methodology for the containment, source term, consequence, and risk integration analyses. Volume 1, Revision 1

    NUREG-1150 examines the risk to the public from five nuclear power plants. The NUREG-1150 plant studies are Level III probabilistic risk assessments (PRAs) and, as such, they consist of four analysis components: accident frequency analysis, accident progression analysis, source term analysis, and consequence analysis. This volume summarizes the methods utilized in performing the last three components and the assembly of these analyses into an overall risk assessment. The NUREG-1150 analysis approach is based on the following ideas: (1) general and relatively fast-running models for the individual analysis components, (2) well-defined interfaces between the individual analysis components, (3) use of Monte Carlo techniques together with an efficient sampling procedure to propagate uncertainties, (4) use of expert panels to develop distributions for important phenomenological issues, and (5) automation of the overall analysis. Many features of the new analysis procedures were adopted to facilitate a comprehensive treatment of uncertainty in the complete risk analysis. Uncertainties in the accident frequency, accident progression and source term analyses were included in the overall uncertainty assessment. The uncertainties in the consequence analysis were not included in this assessment. A large effort was devoted to the development of procedures for obtaining expert opinion and the execution of these procedures to quantify parameters and phenomena for which there is large uncertainty and divergent opinions in the reactor safety community

  4. Evaluation of severe accident risks: Methodology for the containment, source term, consequence, and risk integration analyses; Volume 1, Revision 1

    Gorham, E.D.; Breeding, R.J.; Brown, T.D.; Harper, F.T. [Sandia National Labs., Albuquerque, NM (United States); Helton, J.C. [Arizona State Univ., Tempe, AZ (United States); Murfin, W.B. [Technadyne Engineering Consultants, Inc., Albuquerque, NM (United States); Hora, S.C. [Hawaii Univ., Hilo, HI (United States)

    1993-12-01

    NUREG-1150 examines the risk to the public from five nuclear power plants. The NUREG-1150 plant studies are Level III probabilistic risk assessments (PRAs) and, as such, they consist of four analysis components: accident frequency analysis, accident progression analysis, source term analysis, and consequence analysis. This volume summarizes the methods utilized in performing the last three components and the assembly of these analyses into an overall risk assessment. The NUREG-1150 analysis approach is based on the following ideas: (1) general and relatively fast-running models for the individual analysis components, (2) well-defined interfaces between the individual analysis components, (3) use of Monte Carlo techniques together with an efficient sampling procedure to propagate uncertainties, (4) use of expert panels to develop distributions for important phenomenological issues, and (5) automation of the overall analysis. Many features of the new analysis procedures were adopted to facilitate a comprehensive treatment of uncertainty in the complete risk analysis. Uncertainties in the accident frequency, accident progression and source term analyses were included in the overall uncertainty assessment. The uncertainties in the consequence analysis were not included in this assessment. A large effort was devoted to the development of procedures for obtaining expert opinion and the execution of these procedures to quantify parameters and phenomena for which there is large uncertainty and divergent opinions in the reactor safety community.

  5. Offsite radiological consequence analysis for the bounding flammable gas accident

    The purpose of this analysis is to calculate the offsite radiological consequence of the bounding flammable gas accident. DOE-STD-3009-94, ''Preparation Guide for U.S. Department of Energy Nonreactor Nuclear Facility Documented Safety Analyses'', requires the formal quantification of a limited subset of accidents representing a complete set of bounding conditions. The results of these analyses are then evaluated to determine if they challenge the DOE-STD-3009-94, Appendix A, ''Evaluation Guideline,'' of 25 rem total effective dose equivalent in order to identify and evaluate safety class structures, systems, and components. The bounding flammable gas accident is a detonation in a single-shell tank (SST). A detonation versus a deflagration was selected for analysis because the faster flame speed of a detonation can potentially result in a larger release of respirable material. As will be shown, the consequences of a detonation in either an SST or a double-shell tank (DST) are approximately equal. A detonation in an SST was selected as the bounding condition because the estimated respirable release masses are the same and because the doses per unit quantity of waste inhaled are generally greater for SSTs than for DSTs. Appendix A contains a DST analysis for comparison purposes

  6. Evaluation of nuclear accidents consequences. Risk assessment methodologies, current status and applications

    General description of the structure and process of the probabilistic methods of assessment the external consequences in the event of nuclear accidents is presented. attention is paid in the interface with Probabilistic Safety Analysis level 3 results (source term evaluation) Also are described key issues in accident consequence evaluation as: effects evaluated (early and late health effects and economic effects due to countermeasures), presentation of accident consequences results, computer codes. Briefly are presented some relevant areas for the applications of Accident Consequence Evaluation

  7. Reports of the Chernobyl accident consequences in Brazilian newspapers

    The public perception of the risks associated with nuclear power plants was profoundly influenced by the accidents at Three Mile Island and Chernobyl Power Plants which also served to exacerbate in the last decades the growing mistrust on the 'nuclear industry'. Part of the mistrust had its origin in the arrogance of nuclear spokesmen and in the secretiveness of nuclear programs. However, press agencies have an important role in shaping and upsizing the public awareness against nuclear energy. In this paper we present the results of a survey in reports of some Brazilian popular newspapers on Chernobyl consequences, as measured by the total death toll of the accident, to show the up and down dance of large numbers without any serious judgment. (author)

  8. Applications of probabilistic accident consequence evaluation in Cuba

    Are presented the approaches and results of the application of Accident Consequence Evaluation methodologies in on emergency in the Juragua Nuclear Power Plant site and a population evaluation of a planned NPP site in the east of the country Findings on population sector weighing and assessment of effectiveness of primary countermeasures in the event of sever accidents (SST1 and PWR4 source terms) in Juragua NPP site are discussed Results on comparative risk-based evaluation of the population predicted evolution (in 3 temporal horizons: base year, 2005 year and 2050 year) for the planned site are described. Evaluation also included sector risk weighing, risk importance of small towns in the nearby of the effects on risk of population freezing and relocation of these villages

  9. Chernobyl victims: realistic evaluation of medical consequences of Chernobyl accident

    Objective assessment of early and delayed medical consequence of the Chernobyl accident is presented. Mortality of people due to acute radiation disease, burns and mechanical injuries are attributed to the early effects. Oncological and genetic diseases are considered as the delayed effects. Delayed radiation effects on the residents of contaminated territories were estimated by epidemiologic examination taking into account the dose due to radioactive fallout. Certain regions of Belarus, Russia and Ukraine were mostly exposed to contamination. Contamination density by 137Cs is considered and radiation doses due to natural sources and Chernobyl accident are compared. Disease incidence is analysed for carcinoma and genetic diseases. Health hazard caused by non-radiation accidental factors (psychological stress, victim psychology thrusting, groundless evacuation) is assessed

  10. Radiological consequences of the Three Mile Island accident

    The radiological consequences of the Three Mile Island (TMI) nuclear accident are discussed in detail. The nature, quantity and timing of the radioactive materials released to the atmosphere are established; mainly radioactive noble gases were emitted. A description is given of the radiological monitoring that occurred and the measured levels both inside and outside the plant are given as a function of time from the accident. In particular, the radioiodine release and its subsequent detection in milk analysis is described. The methods of establishing the population dosage are discussed; it is concluded that the collective dose equivalent is in the range 1600-3300 person rems. This implies a projected cancer (fatal and non-fatal) incidence of less than 1.5 in the offsite population within the 50 miles of the TMI site; the expected occurrence in this population is 541,000 cancers. The exposure of workers to radiation levels within the plant is also reported. (U.K.)

  11. Environmental radiological consequences of a loss of coolant accident

    The elaboration of a calculation model to determine safety areas, named Exclusion Zone and Low Population Zone for nuclear power plants, is dealt with. These areas are determined from a radioactive doses calculation for the population living around the NPP after occurence of a postulated ' Maximum Credible Accident' (MCA). The MCA is defined as an accident with complete loss of primary coolant and consequent fusion of a substantial portion of the reactor core. In the calculations carried out, data from NPP Angra I were used and the assumptions made were conservative, to be compatible with licensing requirements. Under the most pessimistic assumption (no filters) the values of 410m and 1000m were obtained for the Exclusion Zone and Low Population Zone radii, respectivily. (Author)

  12. The accident consequence model of the German safety study

    The accident consequence model essentially describes a) the diffusion in the atmosphere and deposition on the soil of radioactive material released from the reactor into the atmosphere; b) the irradiation exposure and health consequences of persons affected. It is used to calculate c) the number of persons suffering from acute or late damage, taking into account possible counteractions such as relocation or evacuation, and d) the total risk to the population from the various types of accident. The model, the underlying parameters and assumptions are described. The bone marrow dose distribution is shown for the case of late overpressure containment failure, which is discussed in the paper of Heuser/Kotthoff, combined with four typical weather conditions. The probability distribution functions for acute mortality, late incidence of cancer and genetic damage are evaluated, assuming a characteristic population distribution. The aim of these calculations is first the presentation of some results of the consequence model as an example, in second the identification of problems, which need possibly in a second phase of study to be evaluated in more detail. (orig.)

  13. Thyroid Consequences of the Fukushima Nuclear Reactor Accident

    Nagataki, Shigenobu

    2012-01-01

    Background A special report, ‘The Fukushima Accident’, was delivered at the 35th Annual Meeting of the European Thyroid Association in Krakow on September 11, 2011, and this study is the follow-up of the special report. Objectives To present a preliminary review of potential thyroid consequences of the 2011 Fukushima nuclear reactor accident. Methods Numerous new data have been presented in Japanese, and most of them are available on the website from each research institute and/or from each m...

  14. Primary disability of the Chernobyl Accident consequences liquidators

    The structure of courses of the primary invalidism of the Chernobyl accident consequences liquidators is studies. The main reasons of the loss of a capacity for work are blood circulation diseases (41.9%), neoplasms (19.9%), diseases of the nervous system and sense organs (9.7%), mental disorders (5.9%) and endocrine diseases (5.5%). The invalids distribution in the different regions and in different age groups according to the disease forms is analysed. The average durations of the diseases resulting in the primary invalidism are about 2.8 years. In average the illnesses began in the 3.1 years. 6 refs

  15. Demonstration uncertainty/sensitivity analysis using the health and economic consequence model CRAC2

    This paper summarizes a demonstration uncertainty/sensitivity analysis performed on the reactor accident consequence model CRAC2. The study was performed with uncertainty/sensitivity analysis techniques compiled as part of the MELCOR program. The principal objectives of the study were: 1) to demonstrate the use of the uncertainty/sensitivity analysis techniques on a health and economic consequence model, 2) to test the computer models which implement the techniques, 3) to identify possible difficulties in performing such an analysis, and 4) to explore alternative means of analyzing, displaying, and describing the results. Demonstration of the applicability of the techniques was the motivation for performing this study; thus, the results should not be taken as a definitive uncertainty analysis of health and economic consequences. Nevertheless, significant insights on health and economic consequence analysis can be drawn from the results of this type of study. Latin hypercube sampling (LHS), a modified Monte Carlo technique, was used in this study. LHS generates a multivariate input structure in which all the variables of interest are varied simultaneously and desired correlations between variables are preserved. LHS has been shown to produce estimates of output distribution functions that are comparable with results of larger random samples

  16. PERSPECTIVES ON A DOE CONSEQUENCE INPUTS FOR ACCIDENT ANALYSIS APPLICATIONS

    (NOEMAIL), K; Jonathan Lowrie, J; David Thoman (NOEMAIL), D; Austin Keller (NOEMAIL), A

    2008-07-30

    Department of Energy (DOE) accident analysis for establishing the required control sets for nuclear facility safety applies a series of simplifying, reasonably conservative assumptions regarding inputs and methodologies for quantifying dose consequences. Most of the analytical practices are conservative, have a technical basis, and are based on regulatory precedent. However, others are judgmental and based on older understanding of phenomenology. The latter type of practices can be found in modeling hypothetical releases into the atmosphere and the subsequent exposure. Often the judgments applied are not based on current technical understanding but on work that has been superseded. The objective of this paper is to review the technical basis for the major inputs and assumptions in the quantification of consequence estimates supporting DOE accident analysis, and to identify those that could be reassessed in light of current understanding of atmospheric dispersion and radiological exposure. Inputs and assumptions of interest include: Meteorological data basis; Breathing rate; and Inhalation dose conversion factor. A simple dose calculation is provided to show the relative difference achieved by improving the technical bases.

  17. Degraded core accidents for the Sizewell PWR A sensitivity analysis of the radiological consequences

    Kelly, G N; Clarke, R H; Ferguson, L; Haywood, S M; Hemming, C R; Jones, J A

    1982-01-01

    The radiological impact of degraded core accidents postulated for the Sizewell PWR was assessed in an earlier study. In this report the sensitivity of the predicted consequences to variation in the values of a number of important parameters is investigated for one of the postulated accidental releases. The parameters subjected to sensitivity analyses are the dose-mortality relationship for bone marrow irradiation, the energy content of the release, the warning time before the release to the environment, and the dry deposition velocity for airborne material. These parameters were identified as among the more important in determining the uncertainty in the results obtained in the initial study. With a few exceptions the predicted consequences were found to be not very sensitive to the parameter values investigated, the range of variation in the consequences for the limiting values of each parameter rarely exceeded a factor of a few and in many cases was considerably less. The conclusions reached are, however, p...

  18. Health effects models for nuclear power plant accident consequence analysis

    The Nuclear Regulatory Commission (NRC) has sponsored several studies to identify and quantify, through the use of models, the potential health effects of accidental releases of radionuclides from nuclear power plants. The Reactor Safety Study provided the basis for most of the earlier estimates related to these health effects. Subsequent efforts by NRC-supported groups resulted in improved health effects models that were published in the report entitled open-quotes Health Effects Models for Nuclear Power Plant Consequence Analysisclose quotes, NUREG/CR-4214, 1985 and revised further in the 1989 report NUREG/CR-4214, Rev. 1, Part 2. The health effects models presented in the 1989 NUREG/CR-4214 report were developed for exposure to low-linear energy transfer (LET) (beta and gamma) radiation based on the best scientific information available at that time. Since the 1989 report was published, two addenda to that report have been prepared to (1) incorporate other scientific information related to low-LET health effects models and (2) extend the models to consider the possible health consequences of the addition of alpha-emitting radionuclides to the exposure source term. The first addendum report, entitled open-quotes Health Effects Models for Nuclear Power Plant Accident Consequence Analysis, Modifications of Models Resulting from Recent Reports on Health Effects of Ionizing Radiation, Low LET Radiation, Part 2: Scientific Bases for Health Effects Models,close quotes was published in 1991 as NUREG/CR-4214, Rev. 1, Part 2, Addendum 1. This second addendum addresses the possibility that some fraction of the accident source term from an operating nuclear power plant comprises alpha-emitting radionuclides. Consideration of chronic high-LET exposure from alpha radiation as well as acute and chronic exposure to low-LET beta and gamma radiations is a reasonable extension of the health effects model

  19. Relevant scenarios and uncertainty analysis of severe accidents in the U.S. EPR

    As part of U.S. EPR design certification activities, AREVA has prepared analyses to support the US NRC's regulatory expectation with regard to the resolution of several severe accident safety issues identified in SECY 93-087. To address the large uncertainties associated with severe accident progression, AREVA NP has developed and applied a best-estimate plus uncertainty methodology to the analysis of severe accidents. The uncertainty methodology considers a broad spectrum of phenomenological and process uncertainties. Unique among the uncertainty parameters considered is the sampling of event sequence (i.e., scenario type). (authors)

  20. Health effects models for nuclear power plant accident consequence analysis

    This report is a revision of NUREG/CR-4214, Rev. 1, Part 1 (1990), Health Effects Models for Nuclear Power Plant Accident Consequence Analysis. This revision has been made to incorporate changes to the Health Effects Models recommended in two addenda to the NUREG/CR-4214, Rev. 1, Part 11, 1989 report. The first of these addenda provided recommended changes to the health effects models for low-LET radiations based on recent reports from UNSCEAR, ICRP and NAS/NRC (BEIR V). The second addendum presented changes needed to incorporate alpha-emitting radionuclides into the accident exposure source term. As in the earlier version of this report, models are provided for early and continuing effects, cancers and thyroid nodules, and genetic effects. Weibull dose-response functions are recommended for evaluating the risks of early and continuing health effects. Three potentially lethal early effects -- the hematopoietic, pulmonary, and gastrointestinal syndromes are considered. Linear and linear-quadratic models are recommended for estimating the risks of seven types of cancer in adults - leukemia, bone, lung, breast, gastrointestinal, thyroid, and ''other''. For most cancers, both incidence and mortality are addressed. Five classes of genetic diseases -- dominant, x-linked, aneuploidy, unbalanced translocations, and multifactorial diseases are also considered. Data are provided that should enable analysts to consider the timing and severity of each type of health risk

  1. Consequences of the nuclear power plant accident at Chernobyl

    The Chernobyl Nuclear Power Plant accident, in the Ukrainian Soviet Socialist Republic (SSR), on April 26, 1986, was the first major nuclear power plant accident that resulted in a large-scale fire and subsequent explosions, immediate and delayed deaths of plant operators and emergency service workers, and the radioactive contamination of a significant land area. The release of radioactive material, over a 10-day period, resulted in millions of Soviets, and other Europeans, being exposed to measurable levels of radioactive fallout. Because of the effects of wind and rain, the radioactive nuclide fallout distribution patterns are not well defined, though they appear to be focused in three contiguous Soviet Republics: the Ukrainian SSR, the Byelorussian SSR, and the Russian Soviet Federated Socialist Republic. Further, because of the many radioactive nuclides (krypton, xenon, cesium, iodine, strontium, plutonium) released by the prolonged fires at Chernobyl, the long-term medical, psychological, social, and economic effects will require careful and prolonged study. Specifically, studies on the medical (leukemia, cancers, thyroid disease) and psychological (reactive depressions, post-traumatic stress disorders, family disorganization) consequences of continued low dose radiation exposure in the affected villages and towns need to be conducted so that a coherent, comprehensive, community-oriented plan may evolve that will not cause those already affected any additional harm and confusion

  2. Consequences of the nuclear power plant accident at Chernobyl

    Ginzburg, H.M.; Reis, E. (Health Resources and Services Administration, Rockville, MD (USA))

    1991-01-01

    The Chernobyl Nuclear Power Plant accident, in the Ukrainian Soviet Socialist Republic (SSR), on April 26, 1986, was the first major nuclear power plant accident that resulted in a large-scale fire and subsequent explosions, immediate and delayed deaths of plant operators and emergency service workers, and the radioactive contamination of a significant land area. The release of radioactive material, over a 10-day period, resulted in millions of Soviets, and other Europeans, being exposed to measurable levels of radioactive fallout. Because of the effects of wind and rain, the radioactive nuclide fallout distribution patterns are not well defined, though they appear to be focused in three contiguous Soviet Republics: the Ukrainian SSR, the Byelorussian SSR, and the Russian Soviet Federated Socialist Republic. Further, because of the many radioactive nuclides (krypton, xenon, cesium, iodine, strontium, plutonium) released by the prolonged fires at Chernobyl, the long-term medical, psychological, social, and economic effects will require careful and prolonged study. Specifically, studies on the medical (leukemia, cancers, thyroid disease) and psychological (reactive depressions, post-traumatic stress disorders, family disorganization) consequences of continued low dose radiation exposure in the affected villages and towns need to be conducted so that a coherent, comprehensive, community-oriented plan may evolve that will not cause those already affected any additional harm and confusion.

  3. Mitigation of Severe Accident Consequences Using Inherent Safety Principles

    The safety challenges associated with sodium-cooled fast reactors have been recognized since the beginning of nuclear power and include the high power density in the core, the need for a reactor coolant and heat transfer system with high heat removal capability, the variation of power across the core requiring the use of ducted assemblies, and the condition that the fuel is not in the most neutronically reactive configuration during normal operation such that relocation can result in positive reactivity excursions, even possibly exceeding prompt critical conditions and energetic events. The potential for accidents with such severe consequences has been a negative factor with respect to the use of the sodium-cooled fast reactor. With the development of inherent safety principles, including favorable reactivity feedback, natural circulation cooling, and design choices resulting in favorable dispersive characteristics for failed fuel, it is possible to greatly increase the level of safety, to the point where it is highly unlikely, or perhaps even not possible, for accidents to result in releases of hghly radioactive materials to the containment or the surrounding environment. (author)

  4. Accident consequence calculations for project W-058 safety analysis

    Accident consequence analyses have been performed for Project W-058, the Replacement Cross Site Transfer System. using the assumption and analysis techniques developed for the Tank Remediation Waste system Basis for Interim Operation. most potential accident involving the FISTS are bounded by the TWRS BIO analysis. However, the spray leak and pool leak scenarios require revised analyses since the RCSTS design utilizes larger diameter pipe and higher pressures than those analyzed in the TWRS BIO. Also the volume of diversion box and vent station are larger than that assumed for the valve pits in the TWRS BIO, which effects results of sprays or spills into the pits. the revised analysis for the spray leak is presented in Section 2, for the above ground spill in Section 3, for the presented in Section 2, for the above ground spill in Section 3, for the subsurface spill forming a pool in Section 4, and for the subsurface pool remaining subsurface in Section 5. The conclusion from these sections are summarized below

  5. Offsite radiological consequence analysis for the bounding aircraft crash accident

    The purpose of this calculation note is to quantitatively analyze a bounding aircraft crash accident for comparison to the DOE-STD-3009-94, ''Preparation Guide for U.S. Department of Energy Nonreactor Nuclear Facility Documented Safety Analyses'', Appendix A, Evaluation Guideline of 25 rem. The potential of aircraft impacting a facility was evaluated using the approach given in DOE-STD-3014-96, ''Accident Analysis for Aircraft Crash into Hazardous Facilities''. The following aircraft crash FR-equencies were determined for the Tank Farms in RPP-11736, ''Assessment Of Aircraft Crash FR-equency For The Hanford Site 200 Area Tank Farms'': (1) The total aircraft crash FR-equency is ''extremely unlikely.'' (2) The general aviation crash FR-equency is ''extremely unlikely.'' (3) The helicopter crash FR-equency is ''beyond extremely unlikely.'' (4) For the Hanford Site 200 Areas, other aircraft type, commercial or military, each above ground facility, and any other type of underground facility is ''beyond extremely unlikely.'' As the potential of aircraft crash into the 200 Area tank farms is more FR-equent than ''beyond extremely unlikely,'' consequence analysis of the aircraft crash is required

  6. Health effects estimation code development for accident consequence analysis

    As part of a computer code system for nuclear reactor accident consequence analysis, two computer codes have been developed for estimating health effects expected to occur following an accident. Health effects models used in the codes are based on the models of NUREG/CR-4214 and are revised for the Japanese population on the basis of the data from the reassessment of the radiation dosimetry and information derived from epidemiological studies on atomic bomb survivors of Hiroshima and Nagasaki. The health effects models include early and continuing effects, late somatic effects and genetic effects. The values of some model parameters are revised for early mortality. The models are modified for predicting late somatic effects such as leukemia and various kinds of cancers. The models for genetic effects are the same as those of NUREG. In order to test the performance of one of these codes, it is applied to the U.S. and Japanese populations. This paper provides descriptions of health effects models used in the two codes and gives comparisons of the mortality risks from each type of cancer for the two populations. (author)

  7. Methods and codes for assessing the off-site Consequences of nuclear accidents. Volume 2

    The Commission of the European Communities, within the framework of its 1980-84 radiation protection research programme, initiated a two-year project in 1983 entitled methods for assessing the radiological impact of accidents (Maria). This project was continued in a substantially enlarged form within the 1985-89 research programme. The main objectives of the project were, firstly, to develop a new probabilistic accident consequence code that was modular, incorporated the best features of those codes already in use, could be readily modified to take account of new data and model developments and would be broadly applicable within the EC; secondly, to acquire a better understanding of the limitations of current models and to develop more rigorous approaches where necessary; and, thirdly, to quantify the uncertainties associated with the model predictions. This research led to the development of the accident consequence code Cosyma (COde System from MAria), which will be made generally available later in 1990. The numerous and diverse studies that have been undertaken in support of this development are summarized in this paper, together with indications of where further effort might be most profitably directed. Consideration is also given to related research directed towards the development of real-time decision support systems for use in off-site emergency management

  8. Guide for licensing evaluations using CRAC2: A computer program for calculating reactor accident consequences

    A version of the CRAC2 computer code applicable for use in analyses of consequences and risks of reactor accidents in case work for environmental statements has been implemented for use on the Nuclear Regulatory Commission Data General MV/8000 computer system. Input preparation is facilitated through the use of an interactive computer program which operates on an IBM personal computer. The resulting CRAC2 input deck is transmitted to the MV/8000 by using an error-free file transfer mechanism. To facilitate the use of CRAC2 at NRC, relevant background material on input requirements and model descriptions has been extracted from four reports - ''Calculations of Reactor Accident Consequences,'' Version 2, NUREG/CR-2326 (SAND81-1994) and ''CRAC2 Model Descriptions,'' NUREG/CR-2552 (SAND82-0342), ''CRAC Calculations for Accident Sections of Environmental Statements, '' NUREG/CR-2901 (SAND82-1693), and ''Sensitivity and Uncertainty Studies of the CRAC2 Computer Code,'' NUREG/CR-4038 (ORNL-6114). When this background information is combined with instructions on the input processor, this report provides a self-contained guide for preparing CRAC2 input data with a specific orientation toward applications on the MV/8000. 8 refs., 11 figs., 10 tabs

  9. Towards more realistic assessment of reactor accident consequences

    The purpose of the Nordic project described in the report has been to improve the data base used in accident consequence assessments, and also to improve the assessment models in use in the Nordic countries. The following data related questions have been dealt with: Terrestrial transfer factors, the freshwater pathways, comparison of dynamic and static calculation models for fish, and the shielding effect of buildings. The work on terrestrial transfer factors has resulted in the generation of a Nordic fallout data bank. The following experimental investigations have been performed: Natural decontamination of roofs under summer and winter conditions, deposition in urban areas, and the filter effect of buildings. Various aspects of mitigating actions have also been examined

  10. Accident consequence assessments with different atmospheric dispersion models

    An essential aim of the improvements of the new program system UFOMOD for Accident Consequence Assessments (ACAs) was to substitute the straight-line Gaussian plume model conventionally used in ACA models by more realistic atmospheric dispersion models. To identify improved models which can be applied in ACA codes and to quantify the implications of different dispersion models on the results of an ACA, probabilistic comparative calculations with different atmospheric dispersion models have been performed. The study showed that there are trajectory models available which can be applied in ACAs and that they provide more realistic results of ACAs than straight-line Gaussian models. This led to a completely novel concept of atmospheric dispersion modelling in which two different distance ranges of validity are distinguished: the near range of some ten kilometres distance and the adjacent far range which are assigned to respective trajectory models. (orig.)

  11. Evaluation of severe accident risks: Quantification of major input parameters: MAACS [MELCOR Accident Consequence Code System] input

    Estimation of offsite accident consequences is the customary final step in a probabilistic assessment of the risks of severe nuclear reactor accidents. Recently, the Nuclear Regulatory Commission reassessed the risks of severe accidents at five US power reactors (NUREG-1150). Offsite accident consequences for NUREG-1150 source terms were estimated using the MELCOR Accident Consequence Code System (MACCS). Before these calculations were performed, most MACCS input parameters were reviewed, and for each parameter reviewed, a best-estimate value was recommended. This report presents the results of these reviews. Specifically, recommended values and the basis for their selection are presented for MACCS atmospheric and biospheric transport, emergency response, food pathway, and economic input parameters. Dose conversion factors and health effect parameters are not reviewed in this report. 134 refs., 15 figs., 110 tabs

  12. Evaluation of severe accident risks: Quantification of major input parameters: MAACS (MELCOR Accident Consequence Code System) input

    Sprung, J.L.; Jow, H-N (Sandia National Labs., Albuquerque, NM (USA)); Rollstin, J.A. (GRAM, Inc., Albuquerque, NM (USA)); Helton, J.C. (Arizona State Univ., Tempe, AZ (USA))

    1990-12-01

    Estimation of offsite accident consequences is the customary final step in a probabilistic assessment of the risks of severe nuclear reactor accidents. Recently, the Nuclear Regulatory Commission reassessed the risks of severe accidents at five US power reactors (NUREG-1150). Offsite accident consequences for NUREG-1150 source terms were estimated using the MELCOR Accident Consequence Code System (MACCS). Before these calculations were performed, most MACCS input parameters were reviewed, and for each parameter reviewed, a best-estimate value was recommended. This report presents the results of these reviews. Specifically, recommended values and the basis for their selection are presented for MACCS atmospheric and biospheric transport, emergency response, food pathway, and economic input parameters. Dose conversion factors and health effect parameters are not reviewed in this report. 134 refs., 15 figs., 110 tabs.

  13. PSYCHIATRIC CONSEQUENCES OF STRESS AFTER A VEHICLE ACCIDENT

    Dickov, Aleksandra; Martinović-Mitrović, Sladjana; Vučković, Nikola; Siladji-Mladenović, Djendji; Mitrović, Dragan; Jovičević, Mirjana; Mišić-Pavkov, Gordana

    2009-01-01

    Background: Vehicle accidents are a common cause of disease and death among people over 30 years of age. Essentially, reaction to stress due to the vehicle accident does not differ from the reaction to other stress factors. There are still no uniform viewpoints about the kind of sequels and their percentage representation after vehicle accidents. Subjects and methods: The research was provided as a prospective study, included 150 subjects who had vehicle accident minimum 2 years prior to t...

  14. A systematic framework for effective uncertainty assessment of severe accident calculations; Hybrid qualitative and quantitative methodology

    This paper describes a systematic framework for characterizing important phenomena and quantifying the degree of contribution of each parameter to the output in severe accident uncertainty assessment. The proposed methodology comprises qualitative as well as quantitative phases. The qualitative part so called Modified PIRT, being a robust process of PIRT for more precise quantification of uncertainties, is a two step process for identifying and ranking based on uncertainty importance in severe accident phenomena. In this process identified severe accident phenomena are ranked according to their effect on the figure of merit and their level of knowledge. Analytical Hierarchical Process (AHP) serves here as a systematic approach for severe accident phenomena ranking. Formal uncertainty importance technique is used to estimate the degree of credibility of the severe accident model(s) used to represent the important phenomena. The methodology uses subjective justification by evaluating available information and data from experiments, and code predictions for this step. The quantitative part utilizes uncertainty importance measures for the quantification of the effect of each input parameter to the output uncertainty. A response surface fitting approach is proposed for estimating associated uncertainties with less calculation cost. The quantitative results are used to plan in reducing epistemic uncertainty in the output variable(s). The application of the proposed methodology is demonstrated for the ACRR MP-2 severe accident test facility. - Highlights: • A two stage framework for severe accident uncertainty analysis is proposed. • Modified PIRT qualitatively identifies and ranks uncertainty sources more precisely. • Uncertainty importance measure quantitatively calculates effect of each uncertainty source. • Methodology is applied successfully on ACRR MP-2 severe accident test facility

  15. Process criticality accident likelihoods, consequences, and emergency planning

    Evaluation of criticality accident risks in the processing of significant quantities of fissile materials is both complex and subjective, largely due to the lack of accident statistics. Thus, complying with standards such as ISO 7753 which mandates that the need for an alarm system be evaluated, is also subjective. A review of guidance found in the literature on potential accident magnitudes is presented for different material forms and arrangements. Reasoned arguments are also presented concerning accident prevention and accident likelihoods for these material forms and arrangements. 13 refs., 1 fig., 1 tab

  16. Evaluation of uncertainties in relation to severe accidents and level-2 probabilistic safety analysis

    Uncertainties of various natures have to be taken into account in severe accident analysis, in particular those related to level-2 probabilistic safety analysis (PSA). However, the extension and application of uncertainty methods to severe accidents is more difficult than for design-basis accidents because of the considerable differences in the availability of experimental data and the level of development and validation of computer codes. Best-estimate approaches used in severe accidents require an assessment of related uncertainties. Besides the evaluation of experimental data scatter, expert judgement is usually needed to assess physical parameter uncertainties, which have to be propagated to results using different techniques. Moreover, the relation between uncertainties and stochastic probabilities (concerning for instance equipment failure and human error), remains an open question, in particular in the framework of level-2 PSAs. The workshop aimed to exchange information about the state of the art in this field and to facilitate the development of a coherent approach to uncertainties in relation to severe accidents. It also provides recommendations for future NEA work in this field. These proceedings gather twenty-four articles shared into four sessions dealing with: 1 - methods for uncertainty assessment, 2 - applications to uncertainty assessment on severe accident physical phenomena, 3 - applications to uncertainty assessment in level 2 PSA, and, 4 - general discussion, conclusions and recommendations

  17. The aftermath of nuclear accidents on mental health; Consequences des accidents radiologiques sur la sante mentale

    Pirard, Ph.; Brenot, J.; Verger, P. [CEA Fontenay-aux-Roses, 92 (France). Inst. de Protection et de Surete Nucleaire

    1998-10-01

    Technological disasters bring about psychological effects in exposed populations of various durability and intensity. This article reviews the epidemiological studies which assess psychological and psychiatric consequences of the Three Mile Island, Goieanna and Chernobyl accidents. It shows, in different accidental and cultural contexts, a statistically significant and durable increase of psychological symptoms in various exposed population groups, which points out an actual psychological distress. Diagnosed psychiatric effects are less constant, but much less studied. Most affected groups are mothers of young children, relocated persons, persons with less social support or in financial trouble. The psychological distress can further psychiatric disorders and give rise to behavioural changes towards health. More research is necessary to delineate the nature and the determinants of the observed symptoms and disorders. It implies to design better tools for the assessment of individual exposure and the diagnosis of mental health effects. (authors)

  18. The primal application research of figure assimilation theory in the nuclear accident consequence forecast

    The deepgoing research of figure assimilation theory promotes many subjects' rapid development. This article outlooks the application of figure assimilation technique in the nuclear accident consequence forecast. The nuclear accident consequence forecast is a complicated system which needs rapidity and precision, so it is quiet difficult. but after the insertion of figure assimilation, it pushes on one step about the question. (authors)

  19. Radiological consequences of the Three Mile Island accident

    The Three Mile Island Accident is described. The pathway and quantity of radioactive materials released, the radiological monitoring results and health effects are discussed. It was concluded that while radiological releases were small in view of the magnitude of fuel damage, the accident indicated that better health physics instrumentation and personnel training is required. (H.K.)

  20. Immediate medical consequences of nuclear accidents: lessons from Chernobyl

    The immediate medical response to the nuclear accident at the Chernobyl nuclear power station involved containment of the radioactivity and evacuation of the nearby population. The next step consisted of assessment of the radiation dose received by individuals, based on biological dosimetry, and treatment of those exposed. Medical care involved treatment of skin burns; measures to support bone marrow failure, gastrointestinal tract injury, and other organ damage (i.e., infection prophylaxis and transfusions) for those with lower radiation dose exposure; and bone marrow transplantation for those exposed to a high dose of radiation. At Chernobyl, two victims died immediately and 29 died of radiation or thermal injuries in the next three months. The remaining victims of the accident are currently well. A nuclear accident anywhere is a nuclear accident everywhere. Prevention and cooperation in response to these accidents are essential goals

  1. A comparison of the consequences of the design basis accident of the Greek Research Reactor with those of a serious realistic accident

    An analysis of the radiological consequences of the design basis and the coolant flow blockage accidents of the Greek Research Reactor is presented. The results indicate that the consequences of the coolant flow blockage accident are practically trivial being 1-2 orders of magnitude lower than the corresponding consequences of the design basis accident. (author)

  2. A study of uncertainties in radiological consequence modeling

    Predicting radiological consequences to humans from radionuclide releases to the environment requires the use of computer models that usually involve a large number of model parameters. Most environmental model parameters, which include the values that quantify the relationships between various media such as the transfer of radionuclides between air, water, soil, vegetation, food, and human tissues, are not readily available on a site-specific basis. Even when they are available, because the values of these parameters vary from location to location and change with changing environmental conditions, the data cannot be precisely determined. In most present-day assessment situations, conservative assumptions are generally used in selecting model parameters. However, with the trend toward lowered regulatory dose/risk limits, the costs associated with this conservatism could be enormous. Concern for unnecessary cost burdens leads naturally to the need for a more accurate representation of the modeling results with the best estimates of the distributions, including the uncertainties of doses likely to be received by humans. This paper presents the results of a study that examined these uncertainties

  3. The role of quantitative uncertainty in the safety analysis of flammable gas accidents in Hanford waste tanks

    Following a 1990 investigation into flammable gas generation, retention, and release mechanisms within the Hanford Site high-level waste tanks, personnel concluded that the existing Authorization Basis documentation did not adequately evaluate flammable gas hazards. The US Department of Energy Headquarters subsequently declared the flammable gas hazard as an unresolved safety issue. Although work scope has been focused on resolution of the issue, it has yet to be resolved due to considerable uncertainty regarding essential technical parameters and associated risk. Resolution of the Flammable Gas Safety Issue will include the identification of a set of controls for the Authorization Basis for the tanks which will require a safety analysis of flammable gas accidents. A traditional nuclear facility safety analysis is based primarily on the analysis of a set of bounding accidents to represent the risks of the possible accidents and hazardous conditions at a facility. While this approach may provide some indication of the bounding consequences of accidents for facilities, it does not provide a satisfactory basis for identification of facility risk or safety controls when there is considerable uncertainty associated with accident phenomena and/or data as is the case with potential flammable gas accidents at the Hanford Site. This is due to the difficulties in identifying the bounding case and reaching consensus among safety analysts, facility operations and engineering, and the regulator on the implications of the safety analysis results. In addition, the bounding cases are frequently based on simplifying assumptions that make the analysis results insensitive to variations among facilities or the impact of alternative safety control strategies. The existing safety analysis of flammable gas accidents for the Tank Waste Remediation system (TWRS) at the Hanford Site has these difficulties. However, Hanford Site personnel are developing a refined safety analysis approach

  4. The consequences from liquid pathways after a reactor meltdown accident

    The potential radiological impact of a core-melt accident on the human population has been investigated. In particular, the radiation dose received from radioactivity which could reach the population via liquid pathways has been considered. Radioactivity could be released directly to the hydrosphere after a core-melt accident as a result of melt-through of the containment basemat followed by any of three processes: (1) leaching of the melt debris; 2 escape of sumpwater through the hole formed by the melt (or from passage out of the containment by an alternate route); and 3) depressurization of the containment atmosphere through the melt hole. The three types of releases would differ primarily in their rates, their magnitudes and their radioactive compositions. Both the containment atmosphere and the sumpwater releases would occur relatively rapidly. However, most of the radionuclides present in these two releases in substantial quantities would be expected to be rather short-lived. Therefore, such releases could have a significant impact at a specific site only if the travel times of the important radionuclides to the human population were small. In contrast, leaching of radionuclides from the melt debris would be expected to occur relatively slowly. Most of the long-lived isotopes would be expected to be found primarily in the melt debris. Consequently, even though this release occurred relatively slowly, the impact could still be significant. In contrast to the situation for releases to the atmosphere, accidents corresponding to the most probable RSS (Reactor Safety Study) meltdown categories would result in the largest releases to the hydrosphere. Furthermore, substantial amounts of radioactivity would generally be expected to be released to the hydrosphere during any meltdown accident involving complete melt-through of the containment basemat. On the basis of subsurface hydrologies alone, sites range from those that essentially preclude any impacts to the human

  5. Prevention of the causes and consequences of a criticality accident - measures adopted in France

    The question of safety in regard to criticality accident risks has two aspects: prevention of the cause and limitation of the consequences. These two aspects are closely connected. The effort devoted to prevention of the causes depends on the seriousness of the possible human psychologic and economic consequences of the accident. The criticality accidents which have occurred in the nuclear industry, though few in number, do reveal the imperfect nature of the techniques adopted to prevent the causes, and also constitute the only available realistic basis for evaluating the consequences and developing measures to limit them. The authors give a analysis of the known causes and consequences of past criticality accidents and on this basis make a number of comments concerning: the validity of traditional safety criteria, the probability of accidents for different types of operations, characteristic accidents which can serve as models, and the extent of possible radiological consequences. The measures adopted in France to limit the consequences of a possible criticality accident under the headings: location, design and lay-out of the installations, accident detection, and dosimetry for the exposed personnel, are briefly described after a short account of the criteria used in deciding on them. (author)

  6. Prevention of "simple accidents at work" with major consequences

    Jørgensen, Kirsten

    2016-01-01

    prevention or safety methodologies and procedures established for major accidents are applicable to simple accidents. The article goes back to basics about accidents causes, to review the nature of successful prevention techniques and to analyze what have been constraints to getting this knowledge used more...... broadly. This review identifies gaps in the prevention of simple accidents, relating to safety barriers for risk control and the management processes that need to be in place to deliver those risk controls in a continuingly effective state. The article introduces the ‘‘INFO cards’’ as a tool for the...... systematic observation of hazard sources in order to ascertain whether safety barriers and management deliveries are present. Safety management and safety culture, together with the INFO cards are important factors in the prevention process. The conclusion is that we must look at safety as a part of being a...

  7. Consequences of the nuclear power plant accident at Chernobyl.

    Ginzburg, H M; Reis, E.

    1991-01-01

    The Chernobyl Nuclear Power Plant accident, in the Ukrainian Soviet Socialist Republic (SSR), on April 26, 1986, was the first major nuclear power plant accident that resulted in a large-scale fire and subsequent explosions, immediate and delayed deaths of plant operators and emergency service workers, and the radioactive contamination of a significant land area. The release of radioactive material, over a 10-day period, resulted in millions of Soviets, and other Europeans, being exposed to m...

  8. Radioecological and dosimetric consequences of Chernobyl accident in France; Consequences radioecologiques et dosimetriques de l`accident de Tchernobyl en France

    Renaud, Ph.; Beaugelin, K.; Maubert, H.; Ledenvic, Ph

    1997-12-31

    After ten years and the taking in account of numerous data, it can be affirmed that the dosimetric consequences of Chernobyl accident will have been limited in France. for the period 1986-2046, the individual middle efficient dose commitment, for the area the most reached by depositing is inferior to 1500 {mu}Sv, that represents about 1% of middle natural exposure in the same time. but mountains and forests can have more important surface activities than in plain. Everywhere else, it can be considered that the effects of Chernobyl accident are disappearing. the levels of cesium 137 are now often inferior to what they were before the accident. (N.C.)

  9. Phenomenological uncertainties in the suspended radionuclide concentrations in containment during severe LWR accidents

    CONTAIN, a code for integrated analysis of containment phenomenologies in complex LWR sever accident sequences, is being applied in a program for evaluating the uncertainties in USNRC-sponsored efforts to better define LWR accident source terms. The Surry TMLB sequence is studied in detail. Aerosol agglomeration uncertainties are found to contribute about an order of magnitude to the overall uncertainty in suspended radionuclides (almost entirely downward uncertainty; i.e., downward with respect to current base case estimates such as BMI-2104). Containment compartmentalization effects contribute substantial uncertainties in either direction, while effects due to complex multicomponent aerosol compositions contribute lesser, but still potentially significant uncertainties (mostly downward). Incomplete treatment of radionuclide decay chains can contribute factor-of-two upward uncertainties

  10. Phenomenological uncertainties in the suspended radionuclide concentrations in containment during severe LWR accidents

    CONTAIN, a code for integrated analysis of containment phenomenologies in complex LWR severe accident sequences, is being applied in a program for evaluating the uncertainties in USNRC-sponsored efforts to better define LWR accident source terms. The Surry TMLB sequence was studied in detail. Aerosol agglomeration uncertainties were found to contribute about an order of magnitude to the overall uncertainty in suspended radionuclides (almost entirely downward uncertainty; i.e., downward with respect to current base case estimates such as BMI-2104). Containment compartmentalization effects contribute substantial uncertainties in either direction, while effects due to complex multicomponent aerosol compositions contribute lesser, but still potentially significant uncertainties (mostly downward). Incomplete treatment of radionuclide decay chains can contribute factor-of-two upward uncertainties

  11. Setup uncertainties: consequences for multi-isocentre stereotactic radiotherapy

    Full text: Beam data for use in dose calculations by planning systems is generally measured under static and controlled conditions. Yet, patient motion and setup uncertainties will effectively blur the resulting dose distributions leading to a discrepancy between planned and delivered dose distributions. This is particularly so for stereotactic radiotherapy where small well-defined fields are used. When multiple isocentres are used (possibly for larger irregular lesions), relative motion of isocentres due to setup variations may have deleterious effects on the intended radiation delivery. The influence of setup uncertainties was examined by performing a three-dimensional convolution of measured off-axis ratio (OAR) data with a Maxwellian distribution, with standard deviations representing several feasible levels of inaccuracy in patient setup. A sample of patient plans (predominantly multi-isocentre plans) were then considered using original (measured) OAR data, and then modified data in order to observe the resulting effect. The effect of systematic localisation error was also considered by examining resulting DVHs as isocentres were shifted by fixed amounts. In all cases considered, the maximum dose varied quite minimally with increase in setup error with the variation decreasing with increasing high-dose volume. The minimum dose however varied more significantly, and this has serious consequences for dose prescription as the minimum dose can be the controlling factor in treatment efficacy. For multi-isocentre plans, the degree of non-uniformity generated by setup error was not as significant as originally expected. This is in part due to the non-uniformity already present in such plans to begin with. Through incorporation of the effect of setup error into planning data, the influence of setup variations on dose distributions for multi-isocentre treatments has been determined. This influence should be considered when creating plans based on the level of spatial

  12. The new program system UFOMOD to assess the consequences of nuclear accidents

    The program system UFOMOD is a completely new accident consequence assessment (ACA) code. Its structure and modelling is based on the experience gained from applications of the old UFOMOD code during and after the German Risk Study - Phase A, the results of scientific investigations performed within both the ongoing Phase B and the CEC-Project MARIA, and the requirements resulting from the extended use of ACAs to help in decision making. One of the most important improvements is the introduction of different trajectory models for describing atmospheric dispersion in the near range and at larger distances. Protective actions and countermeasures modelling takes into account recommendations of international commissions. The dosimetric models contain completely new age-, sex- and time-dependent data of dose-conversion factors for external and internal radiation; the ingestion pathway is modelled to consider seasonal dependencies. New dose-risk-relationships for stochastic and non-stochastic health effects are implemented; a special algorithm developed for ACA codes allows individual and collective leukemia and cancer risks to be presented as a function of time after the accident. According to the modular structure of the new UFOMOD program system, an easy access to parameter values and the results of the various submodels exists what facilitates sensitivity and uncertainty analyses

  13. The program system UFOMOD for assessing the consequences of nuclear accidents

    The programm system UFOMOD is a completely new accident consequence assessment (ACA) code. Its structure and modelling is based on the experience gained from applications of the old UFOMOD code during and after the German Risk Study - Phase A, the results of scientific investigations performed within the ongoing Phase B and the CEC-project MARIA, and the requirements resulting from the extended use of ACAs to help in decision-making. One of the most important improvements is the introduction of different trajecotry models for describing atmospheric dispersion in the near range and at larger distances. Emergency actions and countermeasures modelling takes into account recommendations of international commissions. The dosimetric models contain completely new age-, sex- and time-dependent data of dose-conversion factors for external and internal radiation; the ingestion pathway is modelled to consider seasonal dependencies. New dose-risk-relationships for stochastic and non-stochastic health effects are implemented; a special algorithm developed for ACA codes allows individual and collective leukemia and cancer risks to be presented as a function of time after the accident. According to the modular structure of the new program system UFOMOD, an easy access to parameter values and the results of the various submodels exists what facilitates sensitivity and uncertainty analyses. (orig.)

  14. Parameterization of the driving time in the evacuation or fast relocation model of an accident consequence code

    The model of protective measures in the accident consequence code system UFOMOD of the German Risk Study, Phase B, requires the driving times of the population to be evacuated for the evaluation of the dose received during the evacuation. The parameter values are derived from evacuation simulations carried out with the code EVAS for 36 sectors from various sites. The simulations indicated that the driving time strongly depends on the population density, whereas other influences are less important. It was decided to use different driving times in the consequence code for each of four population density classes as well as for each of three or four fractions of the population in a sector. The variability between sectors of a class was estimated from the 36 sectors, in order to derive subjective probability distributions that are to model the uncertainty in the parameter value to be used for any of the fractions in a particular sector for which an EVAS simulation has not yet been performed. To this end also the impact of the uncertainties in the parameters and modelling assumptions of EVAS on the simulated times was quantified using expert judgement. The distributions permit the derivation of a set of driving times to be used as so-called ''best estimate'' or reference values in the accident consequence code. Additionally they are directly applicable in an uncertainty and sensitivity analysis

  15. The consequences of the Chernobyl nuclear accident in Greece - Report No. 2

    In this report a realistic estimate of the radioactive fallout on Greece from the Chernobyl nuclear accident is described. The measurements performed on environmental samples and samples of the food chain, as well as some realistic estimations for the population doses and the expected consequences of the accident are presented. The analysis has shown that the radiological impact of the accident in Greece can be considered minor. (J.K.)

  16. Radiation-biological consequences of the Chernobyl accident

    The paper points out essential aspects of the actual or potential impact of the Chernobyl reactor accident on human health in the areas immediately affected. In particular, radiation-induced diseases in the population are pointed out, which were caused by radioactive iodine. Epidemiological studies try to establish an increased incidence of leukaemia, lymphomas, and thyroid gland tumours. (DG)

  17. Radiological consequence of Chernobyl nuclear power accident in Japan

    Two years have elapsed since the accident in Chernobyl nuclear power station shocked those concerned with nuclear power generation. The effect that this accident exerted on human environment has still continued directly and indirectly, and the reports on the effect have been made in various countries and by international organizations. In Japan, about the exposure dose of Japanese people due to this accident, the Nuclear Safety Commission and Japan Atomic Energy Research Institute issued the reports. In this report, the available data concerning the envrionmental radioactivity level in Japan due to the Chernobyl accident are collected, and the evaluation of exposure dose which seems most appropriate from the present day scientific viewpoint was attempted by the detailed analysis in the National Institute of Radiological Sciences. The enormous number of the data observed in various parts of Japan were different in sampling, locality, time and measuring method, so difficulty arose frequently. The maximum concentration of I-131 in floating dust was 2.5 Bq/m3 observed in Fukui, and the same kinds of radioactive nuclides as those in Europe were detected. (Kako, I.)

  18. Benefits, Consequences, and Uncertainties of Conventional (Exercise) Countermeasure Approaches

    Ploutz-Snyder, Lori

    2013-01-01

    This presentation will review the pros, cons, and uncertainties of using exercise countermeasures in hypothetical long duration exploration missions. The use of artificial gravity and exercise will be briefly discussed. One benefit to continued use of exercise is related to our extensive experience with spaceflight exercise hardware and programming. Exercise has been a part of each space mission dating back to the 1960's when simple isometric and bungee exercises were performed in the Gemini capsule. Over the next 50 years, exercise hardware improved cumulating in today's ISS suite of exercise equipment: Cycle Ergometer with Vibration Isolation and Stabilization System (CEVIS), Treadmill (T2) and Advanced Resistive Exercise Device (ARED). Today's exercise equipment is the most robust ever to be flown in space and allows the variety and intensity of exercise that might reasonably be expected to maintain muscle mass and function, bone density and cardiovascular fitness. A second benefit is related to the large body of research literature on exercise training. There is a considerable body of supporting research literature including >40,000 peer reviewed research articles on exercise training in humans. A third benefit of exercise is its effectiveness. With the addition of T2 and ARED to our ISS exercise suite, crew member outcomes on standard medical tests have improved. Additionally exercise has other positive side effects such as stress relief, possible improvement of immune function, improved sleep, etc. Exercise is not without its consequences. The major cons to performance of in-flight exercise are the time and equipment required. Currently crew are scheduled 2.5 hrs/day for exercise and there is considerable cost to develop, fly and maintain exercise hardware. While no major injuries have been reported on ISS, there is always some risk of injury with any form of exercise There are several uncertainties going forward; these relate mostly to the development of

  19. The Chernobyl Accident 20 Years On: An Assessment of the Health Consequences and the International Response

    Baverstock, Keith; Williams, Dillwyn

    2006-01-01

    Background The Chernobyl accident in 1986 caused widespread radioactive contamination and enormous concern. Twenty years later, the World Health Organization and the International Atomic Energy Authority issued a generally reassuring statement about the consequences. Accurate assessment of the consequences is important to the current debate on nuclear power. Objectives Our objectives in this study were to evaluate the health impact of the Chernobyl accident, assess the international response ...

  20. The international conference ''one decade after Chernobyl: Summing up the consequences of the accident''

    An International Conference entitled ''One decade after Chernobyl: Summing up the consequences of the accident'' was held at the Austria Center Vienna from 8 to 12 April 1996, the aim being to seek a common and conclusive understanding of the nature and magnitude of the consequences of the Chernobyl accident. The Conference was attended by 845 participants and observers from 71 countries and 20 organizations and covered by 208 journalists from 31 countries and two organizations

  1. Radioecological and dosimetric consequences of the Chernobyl accident in France; Consequences radioecologiques et dosimetriques de l'accident de Tchernobyl en France

    Renaud, Ph.; Beaugelin, K.; Maubert, H.; Ledenvic, Ph. [Inst. de Protection et de Surete Nucleaire, CEA Centre d' Etudes de Fontenay-aux-Roses, 92 (France)

    1997-11-01

    This study has as objective a survey of the radioecological and dosimetric consequences of the Chernobyl accident in France, as well as a prognosis for the years to come. It was requested by the Direction of Nuclear Installation Safety (DSIN) in relation to different organisms which effected measurements after this accident. It is based on the use of combined results of measurements and modelling by means of the code ASTRAL developed at IPSN. Various measurements obtained from five authorities and institutions, were made available, such as: activity of air and water, soil, processed food, agricultural and natural products. However, to achieve the survey still a modelling is needed. ASTRAL is a code for evaluating the ecological consequences of an accident. It allows establishing the correspondence between the soil Remnant Surface Activities (RSA, in Bq.m{sup -2}), the activity concentration of the agricultural production and the individual and collective doses resulting from external and internal exposures (due to inhalation and ingestion of contaminated nurture). The results of principal synthesis documents on the Chernobyl accident and its consequences were also used. The report is structured in nine sections, as follows: 1.Introduction; 2.Objective and methodology; 3.Characterization of radioactive depositions; 4;Remnant surface activities; 5.Contamination of agricultural products and foods; 6.Contamination of natural, semi-natural products and of drinking water; 7.Dosimetric evaluations; 8.Proposals for the environmental surveillance; 9.Conclusion. Finally, after ten years, one concludes that at presentthe dosimetric consequences of the Chernobyl accident in France were rather limited. For the period 1986-2046 the average individual effective dose estimated for the most struck zone is lower than 1500 {mu}Sv, which represents almost 1% of the average natural exposure for the same period. At present, the cesium 137 levels are at often inferior to those recorded

  2. Degraded core accidents for the Sizewell PWR: A sensitivity analysis of the radiological consequences

    The radiological impact of degraded core accidents postulated for the Sizewell PWR was assessed in an earlier study. In this report the sensitivity of the predicted consequences to variation in the values of a number of important parameters is investigated for one of the postulated accidental releases. The parameters subjected to sensitivity analyses are the dose-mortality relationship for bone marrow irradiation, the energy content of the release, the warning time before the release to the environment, and the dry deposition velocity for airborne material. These parameters were identified as among the more important in determining the uncertainty in the results obtained in the initial study. With a few exceptions the predicted consequences were found to be not very sensitive to the parameter values investigated, the range of variation in the consequences for the limiting values of each parameter rarely exceeded a factor of a few and in many cases was considerably less. The conclusions reached are, however, particular to the releases analysed from Sizewell; for different releases from different locations the sensitivity may change significantly. In the earlier study and analysis was undertaken of the impact on the predicted consequences of potential overestimates in the release fractions of radionuclides. Since the results of that study were published some relatively minor numerical errors have been identified. While none of these affects the conclusions reached in that study the opportunity has been taken in this report to present revised values for those results known to be in error. This revised text and results are presented as an appendix to this report and they replace the corresponding material in the earlier study. (author)

  3. Russian National Chernobyl Register as information and and analytical for Chernobyl accident medical consequences estimation

    The paper is devoted to using of the National Radiation and Epidemiology Register basic part, namely the Russian State Medical-Dosimetric Register of the people affected by the Chernobyl accident, to estimate the medical consequences of the accident. First part of article presents the common description and current state of Register. The estimation of medical consequences of the accident for clean-up workers is given in second part. The prognosis of radiation effects and definition of basic epidemiology factors to propose optimal medicalrehabilitation measures is discussed

  4. One decade after Chernobyl. Summing up the consequences of the accident. Proceedings of an international conference

    The consequences attributed to the disastrous accident that occurred at the Chernobyl nuclear power plant on 26 April 1986 have been subjected to extensive scientific examination; however, they are still viewed with widely differing perspectives. It is fitting then that, ten years after the accident, the European Commission (EC), the International Atomic Energy Agency (IAEA) and the World Health Organization (WHO) should jointly sponsor an international conference to review the consequences of the accident and to seek a common and conclusive understanding of their nature and magnitude. The International Conference on One Decade after Chernobyl: Summing up the Consequences of the Accident was held at the Austria Center, Vienna, on 8-12 April 1996. Refs, figs, tabs

  5. Cancer consequences of the Chernobyl accident: 20 years on

    Cardis, Elisabeth [International Agency for Research on Cancer, 150 Cours Albert Thomas, 69372 Lyon CEDEX 08 (France); Howe, Geoffrey [Department of Epidemiology, Mailman School of Public Health, Columbia University, 722 W. 168th Street, Room 1104, New York, NY 10032 (United States); Ron, Elaine [Radiation Epidemiology Branch, Division of Epidemiology and Genetics, National Cancer Institute, Building EPS, MS 7238, Rockville, MD 20852 (United States)] (and others)

    2006-06-15

    26 April 2006 marks the 20th anniversary of the Chernobyl accident. On this occasion, the World Health Organization (WHO), within the UN Chernobyl Forum initiative, convened an Expert Group to evaluate the health impacts of Chernobyl. This paper summarises the findings relating to cancer. A dramatic increase in the incidence of thyroid cancer has been observed among those exposed to radioactive iodines in childhood and adolescence in the most contaminated territories. Iodine deficiency may have increased the risk of developing thyroid cancer following exposure to radioactive iodines, while prolonged stable iodine supplementation in the years after exposure may reduce this risk. Although increases in rates of other cancers have been reported, much of these increases appear to be due to other factors, including improvements in registration, reporting and diagnosis. Studies are few, however, and have methodological limitations. Further, because most radiation-related solid cancers continue to occur decades after exposure and because only 20 years have passed since the accident, it is too early to evaluate the full radiological impact of the accident. Apart from the large increase in thyroid cancer incidence in young people, there are at present no clearly demonstrated radiation-related increases in cancer risk. This should not, however, be interpreted to mean that no increase has in fact occurred: based on the experience of other populations exposed to ionising radiation, a small increase in the relative risk of cancer is expected, even at the low to moderate doses received. Although it is expected that epidemiological studies will have difficulty identifying such a risk, it may nevertheless translate into a substantial number of radiation-related cancer cases in the future, given the very large number of individuals exposed. (rev0009i.

  6. The radioecological consequences of Chernobyl accident for fish

    The estimate of dynamics of radionuclides concentration in muscles of some game-fish from Kiev reservoir and likes in Bryansk region for period after Chernobyl accident was carried out. The concentration of 137Cs in fish has not exceeded the admissible concentration (600 Bq/kg ww) since 1993. The exceptions are the cooling-pond of Chernobyl NPP and Kozlanovskoe Lake where the concentration of 137Cs in fish's muscles exceeded the admissible level more than 5-6 times even in 1995. It was concluded that chronic irradiation of game-fish in water bodies outside 30-km zone would not affect the volume of fishing

  7. Consequences of the Chernobyl accident in France. Thematic sheets; Les consequences de l'accident de Tchernobyl en France. Fiches thematiques

    NONE

    2006-07-01

    This document proposes a set of commented maps, graphs and drawings which illustrate and describe various consequences of the Chernobyl accident in France, such as air contamination (scattering of radioactive particles emitted by the reactor explosion by the wind over thousands of kilometres, evolution of air contamination between April 30 and May 5 1986), ground deposits (influence of rain, heterogeneity of these deposits), contamination of farm products (relationship between the accident date and the deposit characteristics, variable decrease rate of contamination, faster decrease of farm product contamination that caesium radioactive decay since 1987, particular cases of some more sensitive products), health effects (low doses received by the French population, concerns about thyroid cancers)

  8. Uncertainty analysis for fission products transport in CANDU primary heat transport during a severe accident

    Apostol, Mindora; Constantin, Marin [Institute for Nuclear Research, Pitesti (Romania); Leca, Aureliu [Univ. ' Politehnica' of Bucharest (UPB) (Romania)

    2010-08-15

    The work realized under the Severe Accident Research Network of excellence (SARNET) project has shown that the SOPHAEROS module, part of Accident Source Term Evaluation Code (ASTEC) can be fully used to simulate the fission products transport and deposition phenomena in the CANDU Primary Heat Transport (PHT) system. This paper presents an uncertainty analysis for the fission products transport in the CANDU PHT system during a severe accident to obtain the domains of the output parameters, for this study masses of Caesium, Strontium and Iodine deposited in the PHT system and its nodes, taking into account the associated input parameters uncertainties. Five uncertain parameters, the starting time for the releasing process, the duration of the releasing process, the releasing fractions for Cs, Sr and I have been chosen. To generate aleatory values for the uncertain parameters, a method and software have been developed and Monte Carlo simulations to determine uncertainties propagation through the SOPHAEROS module has been carried out. (orig.)

  9. Accident at the Chernobyl nuclear power plant and its consequences

    In the early morning of April 26, 1986, as the culmination of an almost incredible series of errors that began 24 hours earlier, Unit 4 of the Chernobyl nuclear complex, a so-called RBMK-1000 reactor, suffered the worst accident in the history of commercial nuclear power. There was an uncontrolled nuclear excursion, release of a large amount of energy, possibly comparable to hundreds of pounds of TNT, blowing the top off the reactor. There was no containment, in the traditional American sense, so the roof of the building was blown out, an unprecedented amount of radioactivity was released to the biosphere, and a graphite fire was ignited, which burned for days. The radiation that was released spread through Eastern Europe (the world first learned of it through Swedish observations), bringing with it both official and unofficial protests that the Soviet Union had made no announcement of the radiation release until they were, in effect, caught. In fact, after a few days, the Soviets seemed to recognize that nuclear safety is a matter of international concern, and became quite open in their search for cooperation. They invited officials of the International Atomic Energy Agency (IAEA) to visit the area and to fly over the plant, and agreed, in the end, to make a complete disclosure of the details of the accident at a special meeting of IAEA in Vienna, August 25 to 29, 1986. In preparation for that meeting they distributed a lengthy (400 pages) report on the event. This paper reviews this report

  10. Phenomenological uncertainty analysis of containment building pressure load caused by severe accident sequences

    Highlights: • Phenomenological uncertainty analysis has been applied to level 2 PSA. • The methodology provides an alternative to simple deterministic analyses and sensitivity studies. • A realistic evaluation provides a more complete characterization of risks. • Uncertain parameters of MAAP code for the early containment failure were identified. - Abstract: This paper illustrates an application of a severe accident analysis code, MAAP, to the uncertainty evaluation of early containment failure scenarios employed in the containment event tree (CET) model of a reference plant. An uncertainty analysis of containment pressure behavior during severe accidents has been performed for an optimum assessment of an early containment failure model. The present application is mainly focused on determining an estimate of the containment building pressure load caused by severe accident sequences of a nuclear power plant. Key modeling parameters and phenomenological models employed for the present uncertainty analysis are closely related to the in-vessel hydrogen generation, direct containment heating, and gas combustion. The basic approach of this methodology is to (1) develop severe accident scenarios for which containment pressure loads should be performed based on a level 2 PSA, (2) identify severe accident phenomena relevant to an early containment failure, (3) identify the MAAP input parameters, sensitivity coefficients, and modeling options that describe or influence the early containment failure phenomena, (4) prescribe the likelihood descriptions of the potential range of these parameters, and (5) evaluate the code predictions using a number of random combinations of parameter inputs sampled from the likelihood distributions

  11. Severe accident approach - final report. Evaluation of design measures for severe accident prevention and consequence mitigation.

    Tentner, A. M.; Parma, E.; Wei, T.; Wigeland, R.; Nuclear Engineering Division; SNL; INL

    2010-03-01

    An important goal of the US DOE reactor development program is to conceptualize advanced safety design features for a demonstration Sodium Fast Reactor (SFR). The treatment of severe accidents is one of the key safety issues in the design approach for advanced SFR systems. It is necessary to develop an in-depth understanding of the risk of severe accidents for the SFR so that appropriate risk management measures can be implemented early in the design process. This report presents the results of a review of the SFR features and phenomena that directly influence the sequence of events during a postulated severe accident. The report identifies the safety features used or proposed for various SFR designs in the US and worldwide for the prevention and/or mitigation of Core Disruptive Accidents (CDA). The report provides an overview of the current SFR safety approaches and the role of severe accidents. Mutual understanding of these design features and safety approaches is necessary for future collaborations between the US and its international partners as part of the GEN IV program. The report also reviews the basis for an integrated safety approach to severe accidents for the SFR that reflects the safety design knowledge gained in the US during the Advanced Liquid Metal Reactor (ALMR) and Integral Fast Reactor (IFR) programs. This approach relies on inherent reactor and plant safety performance characteristics to provide additional safety margins. The goal of this approach is to prevent development of severe accident conditions, even in the event of initiators with safety system failures previously recognized to lead directly to reactor damage.

  12. Consequences in Norway after a hypothetical accident at Sellafield - Predicted impacts on the environment.

    Thoerring, H.; Liland, A.

    2010-12-15

    This report deals with the environmental consequences in Norway after a hypothetical accident at Sellafield. The investigation is limited to the terrestrial environment, and focus on animals grazing natural pastures, plus wild berries and fungi. Only 137Cs is considered. The predicted consequences are severe, in particular for mutton and goat milk production. (Author)

  13. Consequences in Norway after a hypothetical accident at Sellafield - Predicted impacts on the environment

    This report deals with the environmental consequences in Norway after a hypothetical accident at Sellafield. The investigation is limited to the terrestrial environment, and focus on animals grazing natural pastures, plus wild berries and fungi. Only 137Cs is considered. The predicted consequences are severe - in particular for mutton and goat milk production. (Author)

  14. Small chances - great consequences or the consequences of a large-scale accident in a nuclear power plant

    This report is a sequel to the previous Boerderijcahier (no. 7502) which discussed long-term effects of soil contamination in case of a nuclear power plant accident. In this report the short-term health effects are discussed. Models describing the local consequences of a severe accident are developed, taking into account the possible weather conditions (meteorological model), the evacuation possibilities and the inhabitability of certain areas. In each case long-term and short-term effects are discussed. The safety studies by various departments of the Netherlands' government and the Rasmussen report are commented on

  15. Analysis for relocation strategy using the method of probabilistic accident consequence assessment

    Relocation is one of the long-term protective actions in case of nuclear emergency to mitigate the consequences of an accidental release of radionuclides. The strategy of relocation is characterized by its protective benefit, cost and the corresponding residual dose in planning. This paper describes the application of a probabilistic accident consequence assessment model to the calculation of these quantities and the planning of relocation. Calculations of the consequence have been made of a postulated accident with source terms derived from a generic level 2 PSA. The results provided the insights for the development optimum dose criteria for introducing and terminating relocation. (author)

  16. Health and environmental consequences of the Chernobyl nuclear power plant accident

    An assessment of the impact of the Chernobyl accident on the Northern Hemisphere is presented in this report. It relies heavily on the USSR report presented to the International Atomic Energy Agency. There are gaps in present knowledge and, in some areas, uncertainties may never be completely resolved. What is clearly apparent at this time, however, is that on a large regional scale, the estimates of collective dose have a reasonable level of confidence. The associated potential health impacts have also been projected, together with a range of estimates. A brief description of the tragic consequences to the heroic firefighting and rescue personnel is also provided, and valuable insights regarding acute exposures are developed. Much early effort was expended on estimation of the source term, especially for radiocesium and radioiodine. Several independent analyses are presented that are in reasonable agreement. Atmospheric transport of the radioactive material and its subsequent deposition provide a documented ''umbrella'' of the distributions that form the basic integration of this assessment. The estimates of radiological doses to selected Northern Hemisphere populations were employed in developing an integrated risk assessment of potential latent health effects using the most current models, parameters and risk coefficients. The estimates presented include lower- and upper-bound values, as well as the ''best'' or most realistic ranges. While many scientists believe that minuscule increases in risks to large populations are impossible to prove, it is essential that the magnitude of these possible risks be presented, if only to put an upper limit on the situation. It must be emphasized that while these are ''potential'' health effects, the values presented represent our best current assessment of the health and environmental detriment caused by the Chernobyl accident. 72 refs., 37 figs., 91 tabs

  17. The consequences of the Kyshtym accident for Flora and Fauna

    Flora and fauna irradiated in areas radioactively contaminated by the Kyshtym accident accumulated the bulk of their dose more or less in the first year, with the irradiation being at its most intensive in autumn 1957 and the winter of 1957/58, when plants and many animal species were in the physically dormant state. During the ''acute'' phase the maximum doses absorbed (at a contamination level of 4 000 Ci 90 Sr/km2) were as follows (in krad): mouse-type rodents and fish 4, birch bud meristems 20, pine bud meristems 40, pine needles 80, dormant leaf buds and gramineae seeds on the soil surface 160. The main radiobiological effects appeared in the spring of 1958 and were observed for several years after; subsequently, in the presence of chronic irradiation at a low dose rate, predominantly genetic effects were observed, conifers being the most radiosensitive among the plants. Changes in the structure of herbaceous communities occurred at doses over 20 krad (1 500 Ci 90Sr/km2). In subsequent years we observed changes in the structure and numbers of fish and mouse-type rodent populations. The radioactive contamination caused an increase in the rate of mutational processes in plant and animal populations. However, for populations as a whole the increased frequency observed for most mutations (chromosome aberrations, chemical mutations) did not play a major role, since they were speedily eliminated by natural selection. No deformities of a genetic nature were found on the contaminated territory. In the 30 years since the accident the biological characteristics of the contaminated area have not differed (except for coniferous forests) from those of the surrounding regions. Natural ecosystems are very radioresistant, and extremely high doses are needed to damage them seriously and irreversibly. (author)

  18. Development of evaluation method for economic consequences of severe accident at NPP

    A nuclear power plant accident has onsite and/or offsite consequences. A common framework into which many of the consequences of an accident may be translated is their economic cost. Though there are some consequence analysis codes, these are limited only to estimate only offsite consequence. In this study, economic losses are estimated for the case of onsite and offsite consequences for the sample PWR plant at Yong-Gwang site. For the estimation of offsite consequence, economic database unique to Korean economic structure is utilized as many as possible. By grouping of various cost components, each cost groups are compared each other. For the detailed estimation of offsite decontamination cost, offsite surface around the plant is divided into five types of surface. This division of surface types is agricultural field, wooded land, roof surface for representing house, asphalt road and water surface. But on the water surface, it is assumed that no decontamination operation is required. The comparison shows that at the severe accident, offsite consequences are more severe than onsite consequences. And in agricultural growing season, the consequence even becomes more severe. It also turned out that the importance and selection of much appropriate criteria will play a major role, because the economic consequences are widely varying depending on how the criteria was chosen

  19. Experience with psychological consequences of the Chernobyl nuclear plant accident

    The paper describes the image of radiation menance. Basic differences in image parameters are revealed for some population groups. The psychological levels of the image are regarded as psychological phenomena. Some specific psychological consequences of mental regression are outlined in the paper

  20. About some regularities consequences of accidents at NPP

    In the article are considered the principal reasons of differences in observed and calculation frequencies of emergency events in complex technological systems, including NPP. Analyzed simplification inherent in the probabilistic model of work of the reactor. The results of application of power-law probability distribution are presented for the estimation of consequences of catastrophes in complex and dangerous technologies

  1. One decade after Chernobyl: Summing up the consequences of the accident. Poster presentations

    The consequences attributed to the disastrous accident that occurred at the Chernobyl nuclear power plant on 26 April 1986 have been subjected to extensive scientific examination; however, they are still viewed with widely differing perspectives. It is fitting then that, ten years after the accident, the European Commission (EC), the International Atomic Energy Agency (IAEA) and the World Health Organization (WHO) should jointly sponsor an international conference to review the consequences of the accident and to seek a common and conclusive understanding of their nature and magnitude. The International Conference on One Decade after Chernobyl: Summing up the Consequences of the Accident was held at the Austria Center, Vienna, on 8-12 April 1996. To facilitate the discussions of the Conference, background papers were prepared for the Technical Symposium by teams of scientists from around the world, who collaborated over a period of months to ascertain, consolidate and present the current state of knowledge in six key areas: clinically observed effects; thyroid effects; long term health effects; other health related effects; consequences for the environment; and the consequences in perspective: prognosis for the future. A background paper on the social, economic, institutional and political impact of the accident was prepared by Belarus, the Russian Federation and Ukraine. The conclusions of the Forum on Nuclear Safety Aspects served as a background paper on this topic

  2. One decade after Chernobyl: Summing up the consequences of the accident. Poster presentations

    The consequences attributed to the disastrous accident that occurred at the Chernobyl nuclear power plant on 26 April 1986 have been subjected to extensive scientific examination; however, they are still viewed with widely differing perspectives. It is fitting then that, ten years after the accident, the European commission (EC), the International Atomic Energy Agency (IAEA) and the World Health Organization (WHO) should jointly sponsor an international conference to review the consequences of the accident and to seek a common and conclusive understanding of their nature and magnitude. The International Conference on One Decade after Chernobyl: Summing up the Consequences of the Accident was held at the Austria Center, Vienna, on 8-12 April 1996. To facilitate the discussions of the Conference, background papers were prepared for the Technical Symposium by teams of scientists from a round the world, who collaborated over a period of months to ascertain, consolidate and present the current state of knowledge in six key areas: clinically observed effects; thyroid effects; long term health effects; other health related effects; consequences for the environment; and the consequences in perspective: prognosis for the future. A background paper on the social, economic, institutional and political impact of the accident was prepared by Belarus, the Russian Federation and Ukraine. The conclusions of the Forum on Nuclear Safety Aspects served as a background paper on this topic. Refs, figs, tabs

  3. Help guides for post-accident consequence management: farm activities and exiting the emergency phase

    After having recalled the main actions foreseen in the PPIs (plans particuliers d'intervention, intervention specific plans) in case of radionuclide release in the environment after a nuclear accident, i.e. sheltering and ingestion of steady iodine, and also indicated the different phases of consequence management (preparation, emergency and post-accident phases), this report describes and comments the contents of two guides published by the IRSN (the French Radioprotection and Nuclear Safety Institute) and dealing with the management of post-accident consequences. The first one is a guide to aid to decision-making for the management of the agricultural sector in case of nuclear accident, and the second one is a guide for the preparation of the end of the emergency phase in which actions to be performed during the first week after the end of accidental releases are described

  4. The influence of seasonal conditions on the radiological consequences of a nuclear accident

    The impact of an accidental release of radioactivity to the environment can be strongly influenced by prevailing environmental conditions. Thus, potential variations in accident consequences caused by variable seasonal, meteorological or climatic conditions are of significance to the development and application of protective measures and emergency response plans. These proceedings present the results of a workshop organized by the NEA to examine such aspects of emergency response to a nuclear accident

  5. OFFSITE RADIOLOGICAL CONSEQUENCE CALCULATION FOR THE BOUNDING MIXING OF INCOMPATIBLE MATERIALS ACCIDENT

    This document quantifies the offsite radiological consequence of the bounding mixing of incompatible materials accident for comparison with the 25 rem Evaluation Guideline established in Appendix A of DOE-STD-3009. The bounding accident is an inadvertent addition of acid to a waste tank. The calculated offsite dose does not challenge the Evaluation Guideline. Revision 4 updates the analysis to consider bulk chemical additions to single shell tanks (SSTs)

  6. Accident on the Chernobyl nuclear power plant. Getting over the consequences and lessons learned

    The book is devoted to the 20 anniversary of the accident on the 4th Power Unit of the Chernobyl NPP. The power plant construction history, accident reasons, its consequences, the measures on its liquidation are represented. The current state of activity on the Chernobyl power unit decommission, the 'Shelter' object conversion into the ecologically safe system is described. The future of the Chernobyl NPP site and disposal zone is discussed

  7. Consequences of tractor accidents in the agriculture in Republic of Macedonia

    Dimitrovski, Zoran

    2008-01-01

    In this paper are the results from the research of the consequences of tractor accidents in the agriculture in Republic of Macedonia. During the research from 1999 till 2003, 610 people have been injured in Republic of Macedonia in agricultural production, and the tractors have been the main reason. 544 people have been injured in tractor traffic accidents and 66 have been injured during tractor operating in agricultural condition. From the total number, 101 people have died during this perio...

  8. Proceedings of the Seminar on Methods and Codes for Assessing the off-site consequences of nuclear accidents. Volume 1

    The Commission of the European Communities, within the framework of its 1980-84 radiation protection research programme, initiated a two-year project in 1983 entitled 'methods for assessing the radiological impact of accidents' (Maria). This project was continued in a substantially enlarged form within the 1985-89 research programme. The main objectives of the project were, firstly, to develop a new probabilistic accident consequence code that was modular, incorporated the best features of those codes already in use, could be readily modified to take account of new data and model developments and would be broadly applicable within the EC; secondly, to acquire a better understanding of the limitations of current models and to develop more rigorous approaches where necessary; and, thirdly, to quantify the uncertainties associated with the model predictions. This research led to the development of the accident consequence code Cosyma (COde System from MAria), which will be made generally available later in 1990. The numerous and diverse studies that have been undertaken in support of this development are summarized in this paper, together with indications of where further effort might be most profitably directed. Consideration is also given to related research directed towards the development of real-time decision support systems for use in off-site emergency management

  9. Consequences of the Chernobyl accident for reindeer husbandry in Sweden

    Gustaf Åhman

    1990-09-01

    Full Text Available Large parts of the reindeer hearding area in Sweden were contaminated with radioactive caesium from the Chernobyl fallout. During the first year after the accident no food with activity concentrations exceeding 300 Bq/kg was allowed to be sold in Sweden. This meant that about 75% of all reindeer meat produced in Sweden during the autumn and winter 1986/87 were rejected because of too high caesium activités. In May 1987 the maximum level for Cs-137 in reindeer, game and fresh-water fish was raised to 1500 Bq/kg. During the last two year, 1987/88 and 1988/89, about 25% of the slaughtered reindeer has had activities exceeding this limit. The effective long-time halflife or radiocaesium in reindeer after the nuclear weapon tests in the sixties was about 7 years. If this halflife is correct also for the Chernobyl fallout it will take about 35 years before most of the reinder in Sweden are below the current limit 1500 Bq/kg in the winter. However, by feeding the animals uncontaminated food for about two months, many reindeer can be saved for human consumption.

  10. Reactor accident at the Chernobyl nuclear power plant-Block 4. Effects, countermeasures and consequences

    The findings of the Summary Report on the Chernobyl accident issued by IAEA in September 1986 (International Nuclear Safety Advisory Group (INSAG): Summary Report on the Post-Accident Review Meeting on the Chernobyl Accident. Safety Series No. 78-INSAG-1 Vienna, International Atomic Energy Agency (IAEA). Sept. 1986) are updated, reviewing more recent publications providing more complete information on the events both within and outside the plant. The available information on the resulting radioactive pollution of agriculture and the food chain is discussed considering also the consequences for the future in comparison with the other sources of radioactivity in the environment. 21 refs.; 3 figs.; 3 tabs

  11. ASSESSMENT OF THE FUKUSIMA NUCLEAR POWER PLANT ACCIDENT CONSEQUENCES BY THE POPULATION IN THE FAR EAST

    G. V. Arkhangelskaya

    2012-01-01

    Full Text Available The article analyzes the attitude of the population in the five regions of the Far East to the consequences of the accident at the Fukushimai nuclear power plant, as well as the issues of informing about the accident. The analysis of public opinion is based on the data obtained by anonymous questionnaire survey performed in November 2011. In spite of the rather active informing and objective information on the absence of the contamination, most of the population of the Russian Far East believes that radioactive contamination is presented in the areas of their residence, and the main cause of this contamination is the nuclear accident in Japan.

  12. Assessment of radiation consequences of cabins in a nuclear accident of the nuclear ship

    The author discussed about the spread routes of radioactive nuclides from reactor cabin to other cabins and their distributions in these cabins. Methods and formulas to estimate radioactivities of nuclides and doses received by crews in cabins were established. The radiation consequences of cabins in a nuclear accident was quantified and evaluated. The assessments indicates that the consequences of cabins is light and the doses to the staff will not exceed the dose limits prescribed in standards in a design basis accident, and the consequences of cabins is serious and the doses to the staff will exceed the dose limits prescribed in standards in serious accident. Some suggestions on emergency management and radiation protection were given

  13. Estimates of the financial consequences of nuclear-power-reactor accidents

    This report develops preliminary techniques for estimating the financial consequences of potential nuclear power reactor accidents. Offsite cost estimates are based on CRAC2 calculations. Costs are assigned to health effects as well as property damage. Onsite costs are estimated for worker health effects, replacement power, and cleanup costs. Several classes of costs are not included, such as indirect costs, socio-economic costs, and health care costs. Present value discounting is explained and then used to calculate the life cycle cost of the risks of potential reactor accidents. Results of the financial consequence estimates for 156 reactor-site combinations are summarized, and detailed estimates are provided in an appendix. The results indicate that, in general, onsite costs dominate the consequences of potential accidents

  14. RADIOLOGICAL AND MEDICAL CONSEQUENCES OF THE CHERNOBYL ACCIDENT

    V. G. Bebeshko

    2012-01-01

    Full Text Available From the position of a 25-years’ experience to overcome the health effects of Chernobyl the dynamics of the radiation environment, the first summarizing at the international level (1988, the results of completed research and practical monitoring are analyzed. Cohort of acute radiation syndrome (ARS survivors under medical observation at the S.I. "Research Center for Radiation Medicine of the National Academy of Medical Sciences of Ukraine" is the largest. Within the 25 years the functional state of the major organs and body systems, and metabolic homeostasis for this category of persons were studied, a comprehensive assessment of their health, mental and physical performance were given, and risk factors and peculiarities of stochastic and non-stochastic pathology courses were identified, as well as a system of rehabilitation patients after ARS was developed. ARS survivors are suffering from chronic diseases of internal organs and systems (from 5-7 to 10-12 diagnoses at the same time. A correlation between acute radiation effects and specific HLA phenotypes were revealed. The dynamics of the immune system recovery after irradiation was studied. The role and prognostic value of telomere length and programmed cell death of lymphocytes in the formation of the cellular effects of ionizing radiation were determined for the first time. Differences between spontaneous and radiation-induced acute myeloid leukemias were found. Dose-dependent neuropsychiatric, neurophysiological, neuropsychological and neuroimaging deviations were identified after irradiation at doses above 0.3 Sv. It was shown that the lymphocytes of Chernobyl clean-up workers with doses 350 – 690 mGy can induce "the bystander effect" in the non-irradiated cells even after 19 years after exposure. The rates of cancer incidence and mortality of victims, the lessons and key problems to be solved in the third decade after the Chernobyl accident are considered.

  15. Economic consequences of major accidents in the industrial plants: The case of a nuclear power plant

    These last years, newspapers head-lines have reported various accidents (Mexico City, Bhopal, Chernobyl, ...) which have drawn attention to the fact that the major technological risk is now a reality and that, undoubtedly, industrial decision-makers ought to integrate it into their preoccupations. In addition to the sometimes considerable human problems such accidents engender, their economic consequences may be such that they become significant on a national or even international scale. The aim of the present paper is to analyse these economic effects by using the particular context of a nuclear power plant. The author has deliberately limited his subject to the consequences of a major accident, that is to say a sudden event, theoretically unforeseen and beyond man's control. The qualification major means an accident of which the consequences extend far beyond the industrial plant itself. The direct and indirect economic consequences are analysed from the responsibility point of view as well as from the national and international community's point of view. A paragraph explains how the coverage of the costs can rely on the cooperation of a number of parties: responsible company, state, insurers, customers, etc. The study is broadly based on the experience resulting from the two major accidents which happened in the nuclear industry these last years (Three Mile Island in 1979 and Chernobyl in 1986) and makes use of more theoretical considerations, for example in the field of the economic evaluation of human life. (author). 58 refs, 2 figs, 12 tabs

  16. Uncertainty and sensitivity analysis of TMI-2 accident scenario using simulation based techniques

    The Three Mile Island Unit 2 (TMI-2) accident has been studied extensively, as part of both post-accident technical assessment and follow-up computer code calculations. The models used in computer codes for severe accidents have improved significantly over the years due to better understanding. It was decided to reanalyze the severe accident scenario using current state of the art codes and methodologies. This reanalysis was adopted as a part of the joint standard problem exercise for the Atomic Energy Regulatory Board (AERB) - United States Regulatory Commission (USNRC) bilateral safety meet. The accident scenario was divided into four phases for analysis viz., Phase 1 covers from the accident initiation to the shutdown of the last Reactor Coolant Pumps (RCPs) (0 to 100 min), Phase 2 covers initial fuel heat up and core degradation (100 to 174 min), Phase 3 is the period of recovery of the core water level by operating the reactor coolant pump, and the core reheat that followed (174 to 200 min) and Phase 4 covers refilling of the core by high pressure injection (200 to 300 min). The base case analysis was carried out for all four phases. The majority of the predicted parameters are in good agreement with the observed data. However, some parameters have significant deviations compared to the observed data. These discrepancies have arisen from uncertainties in boundary conditions, such as makeup flow, flow during the RCP 2B transient (Phase 3), models used in the code, the adopted nodalisation schemes, etc. In view of this, uncertainty and sensitivity analyses are carried out using simulation based techniques. The paper deals with uncertainty and sensitivity analyses carried out for the first three phases of the accident scenario.

  17. Uncertainty quantification for accident management using ACE surrogates

    The alternating conditional expectation (ACE) regression method is used to generate RELAP5 surrogates which are then used to determine the distribution of the peak clad temperature (PCT) during the loss of feedwater accident coupled with a subsequent initiation of the feed and bleed (F and B) operation in the Zion-1 nuclear power plant. The construction of the surrogates assumes conditional independence relations among key reactor parameters. The choice of parameters to model is based on the macroscopic balance statements governing the behavior of the reactor. The peak clad temperature is calculated based on the independent variables that are known to be important in determining the success of the F and B operation. The relationship between these independent variables and the plant parameters such as coolant pressure and temperature is represented by surrogates that are constructed based on 45 RELAP5 cases. The time-dependent PCT for different values of F and B parameters is calculated by sampling the independent variables from their probability distributions and propagating the information through two layers of surrogates. The results of our analysis show that the ACE surrogates are able to satisfactorily reproduce the behavior of the plant parameters even though a quasi-static assumption is primarily used in their construction. The PCT is found to be lower in cases where the F and B operation is initiated, compared to the case without F and B, regardless of the F and B parameters used. (authors)

  18. Uncertainty Analysis of the Potential Hazard of MCCI during Severe Accidents for the CANDU6 Plant

    Sooyong Park

    2015-01-01

    Full Text Available This paper illustrates the application of a severe accident analysis computer program to the uncertainty analysis of molten corium-concrete interaction (MCCI phenomena in cases of severe accidents in CANDU6 type plant. The potential hazard of MCCI is a failure of the reactor building owing to the possibility of a calandria vault floor melt-through even though the containment filtered vent system is operated. Meanwhile, the MCCI still has large uncertainties in several phenomena such as a melt spreading area and the extent of water ingression into a continuous debris layer. The purpose of this study is to evaluate the MCCI in the calandria vault floor via an uncertainty analysis using the ISAAC program for the CANDU6.

  19. Formation of decontamination cost calculation model for severe accident consequence assessment

    In previous studies, the authors developed an index “cost per severe accident” to perform a severe accident consequence assessment that can cover various kinds of accident consequences, namely health effects, economic, social and environmental impacts. Though decontamination cost was identified as a major component, it was taken into account using simple and conservative assumptions, which make it difficult to have further discussions. The decontamination cost calculation model was therefore reconsidered. 99 parameters were selected to take into account all decontamination-related issues, and the decontamination cost calculation model was formed. The distributions of all parameters were determined. A sensitivity analysis using the Morris method was performed in order to identify important parameters that have large influence on the cost per severe accident and large extent of interactions with other parameters. We identified 25 important parameters, and fixed most negligible parameters to the median of their distributions to form a simplified decontamination cost calculation model. Calculations of cost per severe accident with the full model (all parameters distributed), and with the simplified model were performed and compared. The differences of the cost per severe accident and its components were not significant, which ensure the validity of the simplified model. The simplified model is used to perform a full scope calculation of the cost per severe accident and compared with the previous study. The decontamination cost increased its importance significantly. (author)

  20. Cohort formation for epidemiological study of medical consequences of the Chernobyl accident

    Belarus State Registry of the Chernobyl-affected population contains information about 276 000 residents of the Republic of Belarus exposed due to the Chernobyl NPP accident. Evidently, the population who lived in the evacuation zone was exposed mostly to radiation and also people participating in the liquidation of the Chernobyl accident consequences (emergency workers) within this zone in early post accident period of the catastrophe. Taking into account this criterion, we singled out the group out of all data files including all people who stayed in the evacuation zone not later than on May 31, 1986. The total number of the group made up 39 548 people including 4251 people who were under 18 at the moment of the accident. By preliminary estimation the number of person-years taking into account the deceased and left out of observation made up at the beginning of 2007- 735 600. During the period since 1986 there was detected 2671 cases of malignant tumors in the cohort and among people who were children and adolescents in 1986 there was registered 106 cases of malignant tumors (82% -thyroid cancer). Among 7483 of the deceased, malignant tumors is the cause of death at 1260 people. At present the real number of alive and remained subjects under observation makes up 25359 people including 2321 people who were under 18 at the moment of the accident. This group will form the base for further prospective research aiming at assessment of medical consequences of the Chernobyl NPP accident. (author)

  1. An assessment of the consequences of a research reactor credible accident release

    An analysis of the consequences of a serious credible accident, a coolant flow blockage accident (CFBA) of the Greek research reactor (GRR) is presented. GRR, a 5 MW swimming pool type reactor, is located within Athens the largest population centre of Greece concentrating 32% of its population. To estimate the source term 31 isotopes are taken into consideration and conservative figures of fission product release are adopted. To estimate the CFBA consequences a CRAC2 consequence model version is used. Doses and individual cancer risk from exposure to the passing radioactive cloud are estimated up to a distance of 20km from the reactor site. Collective exposure and latent health effects due to initial exposure and chronic exposure from inhalation of resuspended radionuclides and exposure to groundshine from contaminated ground are estimated for the total Athens area of 3081000 inhabitants. The results of the analysis suggest that the CFBA consequences are not significant. 10 refs., 9 figs., 2 tabs. (Author)

  2. Critical analysis of accident scenario and consequences modelling applied to light-water reactor power plants for accident categories beyond the design basis accident (DBA)

    A critical analysis and sensitivity study of the modelling of accident scenarios and environmental consequences are presented, for light-water reactor accident categories beyond the standard design-basis-accident category. The first chapter, on ''source term'' deals with the release of fission products from a damaged core inventory and their migration within the primary circuit and the reactor containment. Particular attention is given to the influence of engineering safeguards intervention and of the chemical forms of the released fission products. The second chapter deals with their release to the atmosphere, transport and wet or dry deposition, outlining relevant partial effects and confronting short-duration or prolonged releases. The third chapter presents a variability analysis, for environmental contamination levels, for two extreme hypothetical scenarios, evidencing the importance of plume rise. A numerical plume rise model is outlined

  3. Sensitivity and uncertainty analysis for Ignalina NPP confinement in case of loss of coolant accident

    At present the best-estimate approach in the safety analysis of nuclear power plants is widely used around the world. The application of such approach requires to estimate the uncertainty of the calculated results. Various methodologies are applied in order to determine the uncertainty with the required accuracy. One of them is the statistical methodology developed at GRS mbH in Germany and integrated into the SUSA tool, which was applied for the sensitivity and uncertainty analysis of the thermal-hydraulic parameters inside the confinement (Accident Localisation System) of Ignalina NPP with RBMK-1500 reactor in case of Maximum Design Basis Accident (break of 900 mm diameter pipe). Several parameters that could potentially influence the calculated results were selected for the analysis. A set of input data with different initial values of the selected parameters was generated. In order to receive the results with 95 % probability and 95 % accuracy, 100 runs were performed with COCOSYS code developed at GRS mbH. The calculated results were processed with SUSA tool. The performed analysis showed a rather low dispersion of the results and only in the initial period of the accident. Besides, the analysis showed that there is no threat to the building structures of Ignalina NPP confinement in case of the considered accident scenario. (author)

  4. Probabilistic safety assessment (PSA) for serious accident consequences of nuclear power plant

    An analysis method for the PSA of the serious accident consequences of nuclear power plant was introduced and the operation rules, i.e. U5 rules on avoiding the containment failure of the nuclear power plant was put forward by the France. When the nuclear power plant happened core meltdown accident and caused the raising of internal pressure due to the spray failure of the containment, the U5 rules will make the gas inside the containment releasing to the environment through sand-bed filter, then the pressure in the containment will be relieved. The practical calculation was based on the being built nuclear power plant as the chief source. The effect of U5 rules on the serious accident consequences of the nuclear power plant was analysed. In conclusion, some valuable results were given

  5. Accident consequence studies for large fast breeder reactor containments built of concrete or steel

    A numerical analysis of accident consequences in a fast breeder reactor of commercial size after complete loss-of-heat-sink was performed, using the CONTAIN code. Two containment types were studied, which differ in the material used for shielding, support and confinement structures. It was found that the replacement of concrete as principal construction material by steel offers a significant potential for consequence mitigation in terms of thermal and pressure loads and of retention capability

  6. Consequences of Chernobyl accident for Poland: Retrospective assessment after 10 years

    The regional contamination in Poland after Chernobyl accident has been presented. On this base the biological and medical consequences have been discussed. The neonatal mortality as well as cancer frequency for selected regional population in Poland have been analysed during the last decade. 10 figs, 20 tabs

  7. Environmental decision support system on base of geoinformational technologies for the analysis of nuclear accident consequences

    The report deals with description of the concept and prototype of environmental decision support system (EDSS) for the analysis of late off-site consequences of severe nuclear accidents and analysis, processing and presentation of spatially distributed radioecological data. General description of the available software, use of modem achievements of geostatistics and stochastic simulations for the analysis of spatial data are presented and discussed

  8. Patterns and consequences of inadequate sleep in college students: substance use and motor vehicle accidents.

    Taylor, Daniel J; Bramoweth, Adam D

    2010-06-01

    We examined college sleep patterns and consequences using a cross-sectional design. We found that students get insufficient sleep and frequently use medication and alcohol as sleep aids, use stimulants as alertness aids, and fall asleep at the wheel, or have motor vehicle accidents due to sleepiness. Future studies should focus on effective interventions for sleep in college students. PMID:20472221

  9. Application of GIS in prediction and assessment system of off-site accident consequence for NPP

    The assessment and prediction software system of off-site accident consequence for Guangdong Nuclear Power Plant (GNARD2.0) is a GIS-based software system. The spatial analysis of radioactive materials and doses with geographic information is available in this system. The structure and functions of the GNARD system and the method of applying ArcView GIS are presented

  10. The Role of Countermeasures in Mitigating the Radiological Consequences of Nuclear Power Plant Accidents

    During the Fukushima accident the mitigation actions played an important role to decrease the consequences of the accident. The countermeasures are the actions that should be taken after the occurrence of a nuclear accident to protect the public against the associated risk. The actions may be represented by sheltering, evacuation, distribution of stable iodine tablets and/or relocation. This study represents a comprehensive probabilistic study to investigate the role of the adoption of the countermeasures in case of a hypothetical accident of type LOCA for a nuclear power plant of PWR (1000 Mw) type. This work was achieved through running of the PC COSYMA(1) code. The effective doses in different organs, short and long term health effects, and the associated risks were calculated with and without countermeasures. In addition, the overall costs of the accident and the costs of countermeasures are estimated which represent our first trials to know how much the postulated accident costs. The source term of a hypothetical accident is determined by knowing the activity of the core inventory. The meteorological conditions around the site in addition to the population distribution were utilized as input parameters. The stability conditions and the height of atmospheric boundary layers ABL of the concerned site were determined by developing a computer program utilizing Pasquill-Gifford atmospheric stability conditions. The results showed that, the area around the site requires early and late countermeasures actions after the accident especially in the downwind sectors. For late countermeasures, the duration of relocation ranged from about two to 10 years. The adoption of the countermeasures increases the costs of emergency planning by 40% but reduces the risk associated with the accident. (author)

  11. European expert network for the reduction of uncertainties in severe accident safety issues (EURSAFE)

    EURSAFE thematic network was a concerted action in the sixth framework programme of the European Commission. It established a large consensus among the main actors in nuclear safety on the severe accident issues where large uncertainties still subsist. The conclusions were derived from a first-of-kind phenomena identification and ranking tables (PIRT) on all aspects of severe accident also realised in the frame of the project. Starting from a list of all severe accident phenomena containing approximately 1000 entries and established by the twenty partner organisations, 106 phenomena were retained eventually as both important for safety and still lacking sufficient knowledge. Ultimately, 21 research areas for addressing these phenomena regrouped according to their similarities were identified. A networking structure for implementing and executing the necessary research was proposed, which promotes integration and harmonisation of the different national programmes. A severe accident database structure was proposed to ensure preservation of experimental data and enhanced communication for data exchange and use for severe accident codes assessment. The final product, named EURSAFE, is a website network, http://asa2.jrc.it/eursafe, connecting nodes located at partner sites. As the result of an action involving R and D governmental institutions, regulatory bodies, nuclear industry, utilities and universities from six EU Member States (Finland, France, Germany, Spain, Sweden, UK) plus JRC, three European third countries (Czech Republic, Hungary, Switzerland), and USA, EURSAFE represents a significant step towards harmonisation and credibility of the approaches, and resolution of the remaining severe accident issues

  12. The Fukushima Daiichi Accident. Technical Volume 4/5. Radiological Consequences. Annexes

    The Fukushima Daiichi Accident consists of a Report by the IAEA Director General and five technical volumes. It is the result of an extensive international collaborative effort involving five working groups with about 180 experts from 42 Member States with and without nuclear power programmes and several international bodies. It provides a description of the accident and its causes, evolution and consequences, based on the evaluation of data and information from a large number of sources available at the time of writing. The Fukushima Daiichi Accident will be of use to national authorities, international organizations, nuclear regulatory bodies, nuclear power plant operating organizations, designers of nuclear facilities and other experts in matters relating to nuclear power, as well as the wider public. The set contains six printed parts and five supplementary CD-ROMs. Contents: Report by the Director General; Technical Volume 1/5, Description and Context of the Accident; Technical Volume 2/5, Safety Assessment; Technical Volume 3/5, Emergency Preparedness and Response; Technical Volume 4/5, Radiological Consequences; Technical Volume 5/5, Post-accident Recovery; Annexes. The Report by the Director General is available separately in Arabic, Chinese, English, French, Russian, Spanish and Japanese

  13. The accident at the Chernobyl' nuclear power plant and its consequences

    The material is taken from the conclusions of the Government Commission on the causes of the accident at the fourth unit of the Chernobyl' nuclear power plant and was prepared by a team of experts appointed by the USSR State Committee on the Utilization of Atomic Energy. It contains general material describing the accident, its causes, the action taken to contain the accident and to alleviate its consequences, the radioactive contamination and health of the population and some recommendations for improving nuclear power safety. 7 annexes are devoted to the following topics: water-graphite channel reactors and operating experience with RBMK reactors, design of the reactor plant, elimination of the consequences of the accident and decontamination, estimate of the amount, composition and dynamics of the discharge of radioactive substances from the damaged reactor, atmospheric transport and radioactive contamination of the atmosphere and of the ground, expert evaluation and prediction of the radioecological state of the environment in the area of the radiation plume from the Chernobyl' nuclear power station, medical-biological problems. A separate abstract was prepared for each of these annexes. The slides presented at the post-accident review meeting are grouped in two separate volumes

  14. Overview of Sandia National Laboratories and Khlopin Radium Institute collaborative radiological accident consequence analysis efforts

    In January, 1995 a collaborative effort to improve radiological consequence analysis methods and tools was initiated between the V.G. Khlopin Institute (KRI) and Sandia National Laboratories (SNL). The purpose of the collaborative effort was to transfer SNL's consequence analysis methods to KRI and identify opportunities for collaborative efforts to solve mutual problems relating to the safety of radiochemical facilities. A second purpose was to improve SNL's consequence analysis methods by incorporating the radiological accident field experience of KRI scientists (e.g. the Chernobyl and Kyshtym accidents). The initial collaborative effort focused on the identification of: safety criteria that radiochemical facilities in Russia must meet; analyses/measures required to demonstrate that safety criteria have been met; and data required to complete the analyses/measures identified to demonstrate the safety basis of a facility

  15. The accident at the Chernobyl' nuclear power plant and its consequences. Pt. 1. General material

    The report contains a presentation of the Chernobyl' nuclear power station and of the RBMK-1000 reactor, including its principal physical characteristics, the safety systems and a description of the site and of the surrounding region. After a chronological account of the events which led to the accident and an analysis of the accident using a mathematical model it is concluded that the prime cause of the accident was an extremely improbable combination of violations of instructions and operating rules committed by the staff of the unit. Technical and organizational measures for improving the safety of nuclear power plants with RBMK reactors have been taken. A detailed description of the actions taken to contain the accident and to alleviate its consequences is given and includes the fire fighting at the nuclear power station, the evaluation of the state of the fuel after the accident, the actions taken to limit the consequences of the accident in the core, the measures taken at units 1, 2 and 3 of the nuclear power station, the monitoring and diagnosis of the state of the damaged unit, the decontamination of the site and of the 30 km zone and the long-term entombment of the damaged unit. The measures taken for environmental radioactive contamination monitoring, starting by the assessment of the quantity, composition and dynamics of fission products release from the damaged reactor are described, including the main characteristics of the radioactive contamination of the atmosphere and of the ground, the possible ecological consequences and data on the exposure of plant and emergency service personnel and of the population in the 30 km zone around the plant. The last part of the report presents some recommendations for improving nuclear power safety, including scientific, technical and organizational aspects and international measures. Finally, an overview of the development of nuclear power in the USSR is given

  16. Proceedings of the first international conference 'The radiological consequences of the Chernobyl accident'

    Five main objectives were assigned to the EC/CIS scientific collaborative programme: improvement of the knowledge of the relationship between doses and radiation-induced health effects; updating of the arrangements for off-site emergency management response (shot- and medium term)in the even of a future nuclear accident; assisting the relevant CIS Ministries alleviate the consequences of the Chernobyl accident, in particular in the field of restoration of contaminated territories; elaboration of a scientific basis to definite the content of Community assistance programmes; updating of the local technical infrastructure, and implementation of a large programme of exchange of scientists between both Communities. The topics addressed during the Conference mainly reflect the content of the joint collaborative programme: environmental transfer and decontamination, risk assessment and management, health related issues including dosimetry. The main aims of the Conference are to present the major achievements of the joint EC/CIS collaborative research programme (1992-1995) of the consequences of the Chernobyl accident, and to promote an objective evaluation of them by the international scientific community. The Conference is taking place close to the 10th anniversary of the accident and we hope it will contribute to more objective communication of the health and environmental consequences of the Chernobyl accident, and how these may be mitigated in future. The Conference is expected to be an important milestone in the series of meetings which will take place internationally around the 10th anniversary of the nuclear accident. It also provides a major opportunity for all participants to become acquainted with software developed within the framework of the collaborative programme, namely: Geographical Information Systems displaying contamination levels and dose-commitments; Decision Support Systems for the management of contaminated territories; Decision Support Systems for

  17. Uncertainty analysis for control rod ejection accidents simulated by KIKO3D/TRABCO code system

    Recently, considerable conservatism must be applied in the traditional safety analyses for taking into account the uncertainties originating from the input parameters, approximations in the models, due to the safety reserves, etc. The extreme values for all of the input parameters are supposed in the traditional safety analysis at the same time. Additionally it must be mentioned that the selection of the input parameter values leading to conservative results often is not easy. The main goal of this paper is to present a more realistic methodology for the case of control rod ejection accidents. The applied consistent statistical approach leads to conservative results also, but avoids the unnecessary cumulative conservatism. A method based on a mathematical model ('Two-Sided Statistical Tolerance Intervals', [1-2]) was chosen for the realization of uncertainty analyses of Reactivity Initiated Accidents (RIA). (author)

  18. Advanced Approach to Consider Aleatory and Epistemic Uncertainties for Integral Accident Simulations

    The use of best-estimate codes together with realistic input data generally requires that all potentially important epistemic uncertainties which may affect the code prediction are considered in order to get an adequate quantification of the epistemic uncertainty of the prediction as an expression of the existing imprecise knowledge. To facilitate the performance of the required epistemic uncertainty analyses, methods and corresponding software tools are available like, for instance, the GRS-tool SUSA (Software for Uncertainty and Sensitivity Analysis). However, for risk-informed decision-making, the restriction on epistemic uncertainties alone is not enough. Transients and accident scenarios are also affected by aleatory uncertainties which are due to the unpredictable nature of phenomena. It is essential that aleatory uncertainties are taken into account as well, not only in a simplified and supposedly conservative way but as realistic as possible. The additional consideration of aleatory uncertainties, for instance, on the behavior of the technical system, the performance of plant operators, or on the behavior of the physical process provides a quantification of probabilistically significant accident sequences. Only if a safety analysis is able to account for both epistemic and aleatory uncertainties in a realistic manner, it can provide a well-founded risk-informed answer for decision-making. At GRS, an advanced probabilistic dynamics method was developed to address this problem and to provide a more realistic modeling and assessment of transients and accident scenarios. This method allows for an integral simulation of complex dynamic processes particularly taking into account interactions between the plant dynamics as simulated by a best-estimate code, the dynamics of operator actions and the influence of epistemic and aleatory uncertainties. In this paper, the GRS method MCDET (Monte Carlo Dynamic Event Tree) for probabilistic dynamics analysis is explained

  19. Level of health of cleaners taking part in the Chernobyl accident consequences

    During the period of 1986-1988 about 3,000 Moldova citizens took part in Chernobyl NPP accident consequences elimination. In this article the level of morbidity, disability and mortality among Chernobyl accident consequences liquidation participants is analyzed. As a result of analysis of medical documentation and statistical data was revealed that the sickness rate among disaster fighters 2,3 times higher than general sickness rate of the population in Moldova. Disability in this category is at average of 73 per cent as opposed to the overall index for the population of Moldova - 4,4%, this means it is 17 times higher. Mortality among the participants of the accident at Chernobyl NPP is 6 times higher of general data. The participants of the breakdown elimination of Chernobyl accident consequences are equal in their right with the participants and invalids of war and with the disabled workers. Medical and social security of this group is regulated by the legislation of the Republic of Moldova

  20. Radiation health consequences after the accident of Chernobyl Nuclear Power Plant

    The sources of divergences in health consequences assessment after Chernobyl accident have been discussed. The average data about the cancer incidence in Poland have been presented. On that background the frequency of thyroid cancer, being considered as a result of iodine radionuclides exposure after Chernobyl accident in May 1986, have been performed. The great geographic differences in cancer incidence have been underlined. The observed differences between the selected group of people of different age and sex have been also discussed. 14 refs, 11 tabs, 3 figs

  1. Severe accident modeling and offsite dose consequence evaluations for nuclear power plant emergency planning

    We have investigated the roles of Firewater Addition System and Passive Flooder in ABWR severe accidents, such as LOCA and SBO. The results are apparent that Firewater System is vital in the highly unlikely situation where all AC are lost. Also in this paper, we present EPZDose, an effective and faster-than-real time code for offsite dose consequences predictions and evaluations. Illustrations with the release from our severe accident scenario show friendly and informative user's interface for supporting decision makings in nuclear emergency situations. (author)

  2. V.A. Baraboj. Chernobyl: ten years later. Medical consequences of radiation accidents

    Review of the book - Chernobyl: ten years later. Medical consequences of radiation accidents (Kiev, Chernobylinterinform, 1996) by V.A. Baraboj - is presented. The book is based on experimental data obtained by author and available data of other scientists. It is shown that experiments on rats irradiation demonstrate the same combination of symptoms as persons participated in Chernobyl accident response. Attention is paid to the dosimetric, genetic, phenotypic features of exposed persons. Contributions of chemical hazardous pollutants and psychoemotional stress to the general pattern were also accounted. The importance of the book for specialists and public is accentuated

  3. Evaluation of nuclear accident consequences at INR / Nuclear Fuel Plant at Pitesti site

    In the last years, and especially after the Chernobyl accident, considerable efforts have been devoted to develop computer codes for evaluating the radiological impact of nuclear accident and gathering information on alternative counter measures implementing corresponding to different stages of an accident. One of the most important computer codes developed to this aim is COSYMA for radiological and economical consequences evaluations of accidental release of radioactive contaminants in the atmosphere. The paper presents the results obtained with COSYMA computer code for the case of a serious core damage of TRIGA nuclear reactor from INR / Nuclear Fuel Plant at Pitesti site. The specific meteorological conditions at this site, and data on the distribution of population, agricultural production distribution for risk area were taken into account. Short- and long-term doses to the public in the surrounding area, the contribution of different isotopes and exposure pathways, health effects and air and ground concentrations, are also presented. (authors)

  4. RADIATION-HYGIENIC AND MEDICAL CONSEQUENCES OF THE СHERNOBYL ACCIDENT: RESULTS AND PROGNOSIS

    G. G. Onischenko

    2011-01-01

    Full Text Available An article is devoted to the analysis of the radiation situation in the dynamics during the years since the accident at the Chernobyl nuclear power plant in 1986. Data on the scope of activities fulfilled for the assessment of the territories radioactive contamination levels and foodstuffs contamination levels, on the values of the exposure doses for the population living on the contaminated territories, on the medical and socio-psychological consequences of the Chernobyl accident is presented. Basic norms and principles, used during the protective measures development and introduction, are considered, their effectiveness is demonstrated. Mistakes emerged during protective measures implementation are analyzed, the prognosis of the population exposure dose values for the 70-year period since the accident and main directions of activities for the contaminated territories remediation and normal life conditions restoration for the population at these territories are presented.

  5. Development of information resources package for the Chernobyl accident and its consequences by INIS

    The Chernobyl accident was a global catastrophe that captured global attention and as such literature on the Chernobyl accident and its consequences is an important subject covered by the International Nuclear Information System (INIS) Database. The INIS Database contains about 21000 bibliographic records and 9000 full text documents on this subject from 1986 up to August 2006. Based on these extensive resources INIS released a DVD that contained bibliographic references and full text documents as well a bibliometric study of the Chernobyl references on the occasion of the International Conference entitled 'Chernobyl: Looking Back to Go Forwards' held in Vienna on 6 and 7 September 2005. Subsequently, INIS decided to release Revision 1 of the DVD in August 2006 for the twentieth anniversary of the Chernobyl accident with additional value added information sources. This paper briefly discusses the bibliometric parameters of the references, the contents of DVD and the activities undertaken to produce the Chernobyl information resources package

  6. The ASN and the consequences of the Fukushima-Daiichi nuclear accident

    This Power Point document first recalls the sources of exposure to radiations for the French population, the effects of radiation, and some data on the Chernobyl accident. It presents the ASN, its organisation, its means, its missions. It presents the different French nuclear sites, indicates the mean age of nuclear reactors in the World. It describes the licence renewal process, the safety re-examination process. Then, it addresses the Fukushima accident and more particularly the main challenges after the accident: to restore a safe status for the installations, to manage the contamination of the environment. It addresses the consequences for France, i.e mainly safety additional assessment process which has been launched, and the ASN opinion. It indicates the installations located in the Rhone-Alpes region to be assessed in priority, describes the ASN approach for the next months

  7. Two decades of radiological accidents direct causes, roots causes and consequences

    Rozental Jose de Julio

    2002-01-01

    Full Text Available Practically all Countries utilize radioisotopes in medicine, industry, agriculture and research. The extent to which ionizing radiation practices are employed varies considerably, depending largely upon social and economic conditions and the level of technical skills available in the country. An overview of the majority of practices and the associated hazards will be found in the Table IV to VII of this document. The practices in normal and abnormal operating conditions should follow the basic principles of radiation protection and the Safety of Radiation Sources, considering the IAEA Radiation Protection and the Safety of Radiation Sources, Safety Series 120 and the IAEA Recommendation of the Basic Safety Standards for Radiation Protection, Safety Series Nº 115. The Standards themselves underline the necessity to be able to predict the radiological consequences of emergency conditions and the investigations that should need to be done. This paper describes the major accidents that had happened in the last two decades, provides a methodology for analyses and gives a collection of lessons learned. This will help the Regulatory Authority to review the reasons of vulnerabilities, and to start a Radiation safety and Security Programme to introduce measurescapable to avoid the recurrence of similar events. Although a number of accidents with fatalities have caught the attention of the public in recent year, a safety record has accompanied the widespread use of radiation sources. However, the fact that accidents are uncommon should not give grounds for complacency. No radiological accident is acceptable. From a radiation safety and security of the sources standpoint, accident investigation is necessary to determine what happened, why, when, where and how it occurred and who was (were involved and responsible. The investigation conclusion is an important process toward alertness and feedback to avoid careless attitudes by improving the comprehension

  8. Two decades of radiological accidents direct causes, roots causes and consequences

    Practically all countries utilize radioisotopes in medicine, industry, agriculture and research. The extent to which ionizing radiation practices are employed varies considerably, depending largely upon social and economic conditions and the level of technical skills available in the country. An overview of the majority of practices and the associated hazards will be found in the Table IV to VII of this document.The practices in normal and abnormal operating conditions should follow the basic principles of radiation protection and the Safety of Radiation Sources, considering the IAEA Radiation Protection and the Safety of Radiation Sources, Safety Series 120 and the IAEA Recommendation of the Basic Safety Standards for Radiation Protection, Safety Series 115. The Standards themselves underline the necessity to be able to predict the radiological consequences of emergency conditions and the investigations that should need to be done. This paper describes the major accidents that had happened in the last two decades, provides a methodology for analyses and gives a collection of lessons learned. This will help the Regulatory Authority to review the reasons of vulnerabilities, and to start a Radiation Safety and Security Programme to introduce measures capable to avoid the recurrence of similar events. Although a number of accidents with fatalities have caught the attention of the public in recent year, a safety record has accompanied the widespread use of radiation sources. However, the fact that accidents are uncommon should not give grounds for complacency. No radiological accident is acceptable. From a radiation safety and security of the sources standpoint, accident investigation is necessary to determine what happened, why, when, where, and how it occurred and who was (were) involved and responsible. The investigation conclusion is an important process toward alertness and feedback to avoid careless attitudes by improving the comprehension of Safety Performance

  9. Concept and validation studies of the real-time reactor-accident consequences assessment model ECOSYS

    The Chernobyl accident has demonstrated the urgent need for computer programs for real-time assessment of potential radiological consequences of major reactor accidents and for timely recommendations of useful and cost-efficient counter measures. During the past decade the dynamic radioecological program ECOSYS has been developed for nuclear accident consequence assessment with high resolution in space, time and exposure pathways. The Chernobyl reactor accident leading to relatively high contamination of Southern Germany provided excellent conditions for realistic validation studies of concept, sub-models and parameters of ECOSYS. To this purpose more than 7000 low level and in-situ gamma spectroscopy measurements were performed to study experimentally the behaviour of radionuclides in foodchains and in the urban environment and to compare the results to theoretical predictions of ECOSYS. The results show good agreement in the contamination levels of important food stuffs and in external exposure dose rates from a given surface contamination. Improvements were necessary in the assumptions regarding the food consumption habits which changed considerably - and in the functions describing the weathering off from urban and plant surfaces. The results of this validation study and the concept of the improved computerised model, which has subsequently been converted into a real-time code, are discussed in detail

  10. Evaluation of radiological and economic consequences associated with an accident in a fusion power plant

    Schneider, T. E-mail: schneider@cepn.asso.fr; Lepicard, S.; Saez, R.M.; Cabal, H.; Lechon, Y.; Ward, D.; Hamacher, T.; Aquilonius, K.; Hallberg, B.; Korhonen, R

    2001-11-01

    The evaluation of the external costs associated with an accident in a fusion power plant points out that the consequences of such an event, as far as health and environmental impacts are concerned, remain rather limited. This paper presents the main components of the evaluation on accident, performed in the framework of the Studies on Socio-Economic Research on Fusion SERF under the EURATOM agreement. This evaluation, limited to the health and environmental impacts, shows that the external costs of the fusion accident is in the range of 10{sup -5}-10{sup -4} mEURO/kW h while the total external costs for fusion are estimated in the range of a few mEURO per kilowatt hour. It should be noted that even with the integration of risk aversion, the external cost associated with the accident scenario for fusion power plant still remains quite limited due to the low radiological impacts that would have to support the populations surrounding the power plant if an accident occurred, especially the absence of evacuation and relocation of the population and the very limited constraints on food products.

  11. Evaluation of radiological and economic consequences associated with an accident in a fusion power plant

    The evaluation of the external costs associated with an accident in a fusion power plant points out that the consequences of such an event, as far as health and environmental impacts are concerned, remain rather limited. This paper presents the main components of the evaluation on accident, performed in the framework of the Studies on Socio-Economic Research on Fusion SERF under the EURATOM agreement. This evaluation, limited to the health and environmental impacts, shows that the external costs of the fusion accident is in the range of 10-5-10-4 mEURO/kW h while the total external costs for fusion are estimated in the range of a few mEURO per kilowatt hour. It should be noted that even with the integration of risk aversion, the external cost associated with the accident scenario for fusion power plant still remains quite limited due to the low radiological impacts that would have to support the populations surrounding the power plant if an accident occurred, especially the absence of evacuation and relocation of the population and the very limited constraints on food products

  12. Uncertainty analysis of preclosure accident doses for the Yucca Mountain repository

    This study presents a generic methodology that can be used to evaluate the uncertainty in the calculated accidental offsite doses at the Yucca Mountain repository during the preclosure period. For demonstration purposes, this methodology is applied to two specific accident scenarios: The first involves a crane dropping an open container with consolidated fuel rods, the second involves container failure during emplacement or removal operations. The uncertainties of thirteen parameters are quantified by various types of probability distributions. The Latin Hypercube Sampling method is used to evaluate the uncertainty of the offsite dose. For the crane-drop scenario with concurrent filter failure, the doses due to the release of airborne fuel particles are calculated to be 0.019, 0.32, and 2.8 rem at confidence levels of 10%, 50%, and 90%, respectively. For the container failure scenario with concurrent filter failure, the 90% confidence-level dose is 0.21 rem

  13. A review of the uncertainties in the assessment of radiological consequences of spent nuclear fuel disposal

    Radioactive waste disposal systems for spent nuclear fuel are designed to isolate the radioactive waste from the human environment for long period of time. The isolation is provided by a combination of engineered and natural barriers. Safety assessments are performed to describe and quantify the performance of the individual barriers and the disposal system over long-term periods. These assessments will always be associated with uncertainties. Uncertainties can originate from the variability of natural systems and will also be introduced in the predictive modelling performed to quantitatively evaluate the behaviour of the disposal system as a consequence of the incomplete knowledge about the governing processes. Uncertainties in safety assessments can partly be reduced by additional measurements and research. The aim of this study has been to identify uncertainties in assessments of radiological consequences from the disposal of spent nuclear fuel based on the Swedish KBS-3 concept. The identified uncertainties have been classified with respect to their origin, i.e. in conceptual, modelling and data uncertainties. The possibilities to reduce the uncertainties are also commented upon. In assessments it is important to decrease uncertainties which are of major importance for the performance of the disposal system. These could to some extent be identified by uncertainty analysis. However, conceptual uncertainties and some type of model uncertainties are difficult to evaluate. To be able to decrease uncertainties in conceptual models, it is essential that the processes describing and influencing the radionuclide transport in the engineered and natural barriers are sufficiently understood. In this study a qualitative approach has been used. The importance of different barriers and processes are indicated by their influence on the release of some representative radionuclides. (122 refs.) (au)

  14. A review of the uncertainties in the assessment of radiological consequences of spent nuclear fuel disposal

    Radioactive waste disposal systems for spent nuclear fuel are designed to isolate the radioactive waste from the human environment for long periods of time. The isolation is provided by a combination of engineered and natural barriers. Safety assessments are performed to describe and quantify the performance of the individual barriers and the disposal system over long-term periods. These assessments will always be associated with uncertainties. Uncertainties can originate from the variability of natural systems and will also be introduced in the predictive modelling performed to quantitatively evaluate the behavior of the disposal system as a consequence of the incomplete knowledge about the governing processes. Uncertainties in safety assessments can partly be reduced by additional measurements and research. The aim of this study has been to identify uncertainties in assessments of radiological consequences from the disposal of spent nuclear fuel based on the Swedish KBS-3 concept. The identified uncertainties have been classified with respect to their origin, i.e. in conceptual, modelling and data uncertainties. The possibilities to reduce the uncertainties are also commented upon. In assessments it is important to decrease uncertainties which are of major importance for the performance of the disposal system. These could to some extent be identified by uncertainty analysis. However, conceptual uncertainties and some types of model uncertainties are difficult to evaluate. To be able to decrease uncertainties in conceptual models, it is essential that the processes describing and influencing the radionuclide transport in the engineered and natural barriers are sufficiently understood. In this study a qualitative approach has been used. The importance of different barriers and processes are indicated by their influence on the release of some representative radionuclides. (au)

  15. Adaptation of COSYMA and assessment of accident consequences for Daya Bay nuclear power plant in China

    The program package COSYMA for assessing the radiological and economic consequences of nuclear accidents, developed with the support of the European Commission, was applied to investigate the health effects and risks from accidental releases of radioactive material from the Daya Bay nuclear power plant. Population distribution data in the range of 80 km around the site and hourly meteorological data for the year 1985 representative of accident consequence analysis were used. The results showed that early effects are more important at distances closer to the site, while the number of fatal cancers is closely related to the population density and the late effects are still important at distances larger than 50 km from the site. The mean annual expected values for early mortality and late mortality estimated for the population within a circle of 80 km around the Daya Bay nuclear power plant are 4.5x10-3 and 0.1 yr-1, respectively

  16. Environmental consequences of the Chernobyl accident and their remediation: Twenty years of experience

    The explosion on 26 April 1986 at the Chernobyl Nuclear Power Plant located just 100 km from the city of Kyiv in what was then the Soviet Union and now is Ukraine, and consequent ten days' reactor fire resulted in an unprecedented release of radiation and unpredicted adverse consequences both for the public and the environment. Indeed, the IAEA has characterized the event as the 'foremost nuclear catastrophe in human history' and the largest regional release of radionuclides into the atmosphere. Massive radioactive contamination forced the evacuation of more than 100,000 people from the affected region during 1986, and the relocation, after 1986, of another 200,000 from Belarus, the Russian Federation and Ukraine. Some five million people continue to live in areas contaminated by the accident and have to deal with its environmental, health, social and economic consequences. The national governments of the three affected countries, supported by international organizations, have undertaken costly efforts to remedy contamination, provide medical services and restore the region's social and economic well-being. The accident's consequences were not limited to the territories of Belarus, Russia and Ukraine but resulted in substantial transboundary atmospheric transfer and subsequent contamination of numerous European countries that also encountered problems of radiation protection of their populations, although to less extent than the three more affected countries. Although the accident occurred nearly two decades ago, controversy still surrounds the impact of the nuclear disaster. Therefore the IAEA, in cooperation with FAO, UNDP, UNEP, UNOCHA, UNSCEAR, WHO and The World Bank, as well as the competent authorities of Belarus, the Russian Federation and Ukraine, established the Chernobyl Forum in 2003. The mission of the Forum was - through a series of managerial and expert meetings to generate 'authoritative consensual statements' on the environmental consequences and

  17. Final report of the accident phenomenology and consequence (APAC) methodology evaluation. Spills Working Group

    Brereton, S.; Shinn, J. [Lawrence Livermore National Lab., CA (United States); Hesse, D [Battelle Columbus Labs., OH (United States); Kaninich, D. [Westinghouse Savannah River Co., Aiken, SC (United States); Lazaro, M. [Argonne National Lab., IL (United States); Mubayi, V. [Brookhaven National Lab., Upton, NY (United States)

    1997-08-01

    The Spills Working Group was one of six working groups established under the Accident Phenomenology and Consequence (APAC) methodology evaluation program. The objectives of APAC were to assess methodologies available in the accident phenomenology and consequence analysis area and to evaluate their adequacy for use in preparing DOE facility safety basis documentation, such as Basis for Interim Operation (BIO), Justification for Continued Operation (JCO), Hazard Analysis Documents, and Safety Analysis Reports (SARs). Additional objectives of APAC were to identify development needs and to define standard practices to be followed in the analyses supporting facility safety basis documentation. The Spills Working Group focused on methodologies for estimating four types of spill source terms: liquid chemical spills and evaporation, pressurized liquid/gas releases, solid spills and resuspension/sublimation, and resuspension of particulate matter from liquid spills.

  18. German offsite accident consequence model for nuclear facilities: further development and application

    The German Offsite Accident Consequence Model - first applied in the German Risk Study for nuclear power plants with light water reactors - has been further developed with the improvement of several important submodels in the areas of atmospheric dispersion, shielding effects of houses, and the foodchains. To aid interpretation, the presentation of results has been extended with special emphasis on the presentation of the loss of life expectancy. The accident consequence model has been further developed for application to risk assessments for other nuclear facilities, e.g., the liquid metal fast breeder reactor (SNR-300) and the high temperature gas cooled reactor. Moreover the model have been further developed in the area of optimal countermeasure strategies (sheltering, evacuation, etc.) in the case of the Central European conditions. Preliminary considerations has been performed in connection with safety goals on the basis of doses

  19. The usefulness of time-dependent reactor accident consequence modelling for emergency response planning

    After major releases of radionuclides into the atmosphere fast reaction of authorities will be necessary to inform the public of potential consequences and to consider and optimize mitigating actions. These activities require availability of well designed computer models, adequate and fast measurements and prior training of responsible persons. The quantitative assessment models should be capable of taking into account of actual atmospheric dispersion conditions, actual deposition situation (dry, rain, snow, fog), seasonal status of the agriculture, food processing and distribution pathways, etc. In this paper the usefulness of such models will be discussed, their limitations, the relative importance of exposure pathways and a selection of important methods to decrease the activity in food products after an accident. Real-time reactor accident consequence models should be considered as a condition sine qua non for responsible use of nuclear power for electricity production

  20. The role of uncertainty and subjective influences on consequence assessment by aquatic biosecurity experts.

    Davidson, Alisha Dahlstrom; Campbell, Marnie L; Hewitt, Chad L

    2013-09-30

    Expert judgement is often used to mitigate the knowledge gaps that limit understanding of aquatic non-indigenous species (ANS) impacts (consequences) to environmental, economic, social, cultural and human health values. To understand how this uncertainty may affect expert decision making, we explored the presence and effects of uncertainty on consequence assessment for 10 ANS by scientists and managers. We hypothesized species' distribution, taxonomy and impact type will affect assessment magnitude. These hypotheses were partially supported. We also hypothesized a difference in the relationship between consequence magnitude and uncertainty, based on assessor group. This set of hypotheses was not supported, as all group assessments had a significant negative correlation between consequence and uncertainty. Both scientists and managers assigned lower consequence when faced with knowledge gaps and other forms of uncertainty. This aligns with an "innocent until proven guilty" or hindsight approach, as opposed to a "guilty until proven innocent" or precaution approach. Based on these outcomes, the experts appeared to make decisions in violation of both the maximin principle and precaution, instead using a heuristic approach. We suggest several management strategies to prevent biases against environmental protection that occur due to use of the hindsight approach. PMID:23685271

  1. An assessment of the radiological consequences of accidents in research reactors

    This work analyses the radiological consequences of accidents in two types of research reactors: a 5 MWt open pool reactor and a 50 MWt PWR reactor. Two siting cases have been considered: the reactor located near to a large population center and sited in a rural area. The influence of several factors such as source term, meteorological conditions and population distribution have been considered in the present analysis. (author)

  2. Measures for reduction of severe accident consequences: Comprehensive evaluation of the results sponsored by the BMI

    A number of analytical studies were initial in the past by the Federal Ministry of Interior (BMI) of FRG, to investigate the potential of additional constructive measures for risk reduction. Those measures were proposed especially against uncontrolled overpressurization of the containment due to continuous gas/steam generation, penetration of the foundation of the reactor building by melt-concrete interaction, and failure of the containment due to violent hydrogen combustion. This report gives an overview about those studies and summarizes their results. Concerning uncontrolled overpressurization, only filtered venting may be a reasonable measure, while it seems to make not much sense, to look at measures against penetration of the foundation like 'core-catcher' in further detail. To prevent hydrogen combustion with severe consequences, several potential possibilities exist, but none of them can be considered as a safe measure. Additional analysis concerning hydrogen distribution and combustion in a multi-compartment containment are necessary. All studies mentioned in this report, deal with additional constructive measures to mitigate the consequences of severe accidents. Up to day in FRG, the potential of accident prevention and mitigation of its consequences by still or again operable and already existing systems of a plant have not been investigated in detail. As indicated by first results, the use of those systems in the frame of an appropriate accident management may have a large potential for risk reduction. (orig.)

  3. The fallout in France of the Chernobyl accident. Radioecological and dosimetric consequences; Les retombees en France de l'accident de Tchernobyl. Consequences radioecologiques et dosimetriques

    Renaud, Ph.; Beaugelin, K.; Maubert, H.; Ledenvic, Ph. [CEA Fontenay-aux-Roses, 92 (France). Inst. de Protection et de Surete Nucleaire

    1999-07-01

    For the first time, the whole of scientific data available has been gathered and exploited thanks to the ASTRAL model, developed at the Institute of protection and nuclear safety, (IPSN). This model has allowed to explain the principal causes of land and food contamination, as well their potential consequences on the human being. This book has elaborated with the help of every organism that has made radioactivity measurements in environment and man and his feeding. The extent of information sources used in this work makes of it a reference work. It allows to estimate the impact, in France of the Chernobyl accident on each of us and to understand the transfer mechanisms of radioactivity in environment. (N.C.)

  4. Radiological consequences of accidents during disposal of spent nuclear fuel in a deep borehole

    Grundfelt, Bertil [Kemakta Konsult AB, Stockholm (Sweden)

    2013-07-15

    In this report, an analysis of the radiological consequences of potential accidents during disposal of spent nuclear fuel in deep boreholes is presented. The results presented should be seen as coarse estimates of possible radiological consequences of a canister being stuck in a borehole during disposal rather than being the results of a full safety analysis. In the concept for deep borehole disposal of spent nuclear fuel developed by Sandia National Laboratories, the fuel is assumed to be encapsulated in mild steel canisters and stacked between 3 and 5 km depth in boreholes that are cased with perforated mild steel casing tubes. The canisters are joined together by couplings to form strings of 40 canisters and lowered into the borehole. When a canister string has been emplaced in the borehole, a bridge plug is installed above the string and a 10 metres long concrete plug is cast on top of the bridge plug creating a floor for the disposal of the next sting. In total 10 canister strings, in all 400 canisters, are assumed to be disposed of at between 3 and 5 kilometres depth in one borehole. An analysis of potential accidents during the disposal operations shows that the potentially worst accident would be that a canister string is stuck above the disposal zone of a borehole and cannot be retrieved. In such a case, the borehole may have to be sealed in the best possible way and abandoned. The consequences of this could be that one or more leaking canisters are stuck in a borehole section with mobile groundwater. In the case of a leaking canister being stuck in a borehole section with mobile groundwater, the potential radiological consequences are likely to be dominated by the release of the so-called Instant Release Fraction (IRF) of the radionuclide inventory, i.e. the fraction of the radionuclides that as a consequence of the in-core conditions are present in the annulus between the fuel pellets and the cladding or on the grain boundaries of the UO{sub 2} matrix

  5. Fukushima, one year after. First analyses of the accident and of its consequences

    This report proposes assessments and discussions of knowledge gathered by the IRSN during the first twelve months following the Fukushima accident to understand the status of the installations, to assess the releases, and to analyse and assess the consequences of the accident on workers and the impact on the population and environment. After a description of a boiling water reactor (general description, confinement barriers, safeguard systems), and of the earthquake, the authors describe and comment the consequences for several reactors (Fukushima-Dai-ini, Onagawa, Tokai, Higashidoru and Hamaoka). Then, they more precisely describe the Fukushima-Dai-ichi accident by distinguishing different periods (first two weeks, next three weeks, after the 17 of April). They analyse and comment the environmental impact in Japan (atmospheric dispersion of radioactive releases, ground contamination, impact of radioactive fallouts, contamination of the marine environment, and predictable impact on marine and ground ecosystems). They describe the actions undertaken to protect the population and in terms of post-accidental management, comment assessments of the dosimetric and health impact (workers and population exposure). They finally discuss the long range impact

  6. Družbenoekonomsko vrednotenje posledic prometnih nezgod na cestah v Sloveniji: Socioeconomic evaluation of road accident consequences in Slovenia:

    Bensa, Bruno; Kristl, Marko

    2004-01-01

    The goal of the research was to collect and merge data on traffic accidents and their consequences, collected by different institutions. The information formed the basis for calculations of socio-economic costs for the dead and injured in traffic accidents, as well as for estimates of material costs. In addition, an opinion poll on individual evaluation of costs related to trafficaccidents was conducted, and a traffic-accident information system was modeled with the purpose to enhance integra...

  7. Consequences in Norway after a hypothetical accident at Sellafield - Predicted impacts on the environment

    This report describes the possible environmental consequences for Norway due to a hypothetical accident at the Sellafield complex in the UK. The scenario considered involves an explosion and fire at the B215 facility resulting in a 1 % release of the total HAL (Highly Active liquor) inventory of radioactive waste with a subsequent air transport and deposition in Norway. Air transport modelling is based on real meteorological data from October 2008 with wind direction towards Norway and heavy precipitation. This weather is considered to be quite representative as typical seasonal weather. Based on this weather scenario, the estimated fallout in Norway will be ∼ 17 P Bq of caesium-137 which is 7 times higher than the fallout from the Chernobyl accident. The modelled radioactive contamination is linked with data on transfer to the food chain and statistics on production and hunting to assess the consequences for foodstuffs. The investigation has been limited to the terrestrial environment, focussing on wild berries, fungi, and animals grazing unimproved pastures (i.e. various types of game, reindeer, sheep and goats). The predicted consequences are severe - especially in connection to sheep and goat production. Up to 80 % of the lambs in Norway could be exceeding the food intervention levels for radiocaesium the first years after the fallout, with 30-40 % likely to be above for many years. There will, consequently, be a need for extensive countermeasures in large areas for years or even decades involving several hundred thousand animals each year. Large consequences are also expected for reindeer husbandry - the first year in particular due to the time of fallout which is just prior to winter slaughter. The consequences will be most sever for reindeer herding in middle and southern parts of Norway, but problems may reach as far north as Finnmark where we find the majority of Norwegian reindeer production. The consequences for game will mostly depend on the regional

  8. Quantitative uncertainty and sensitivity analysis of a PWR control rod ejection accident

    Pasichnyk, I.; Perin, Y.; Velkov, K. [Gesellschaft flier Anlagen- und Reaktorsicherheit - GRS mbH, Boltzmannstasse 14, 85748 Garching bei Muenchen (Germany)

    2013-07-01

    The paper describes the results of the quantitative Uncertainty and Sensitivity (U/S) Analysis of a Rod Ejection Accident (REA) which is simulated by the coupled system code ATHLET-QUABOX/CUBBOX applying the GRS tool for U/S analysis SUSA/XSUSA. For the present study, a UOX/MOX mixed core loading based on a generic PWR is modeled. A control rod ejection is calculated for two reactor states: Hot Zero Power (HZP) and 30% of nominal power. The worst cases for the rod ejection are determined by steady-state neutronic simulations taking into account the maximum reactivity insertion in the system and the power peaking factor. For the U/S analysis 378 uncertain parameters are identified and quantified (thermal-hydraulic initial and boundary conditions, input parameters and variations of the two-group cross sections). Results for uncertainty and sensitivity analysis are presented for safety important global and local parameters. (authors)

  9. Accident consequence analysis models applied to licensing process of nuclear installations, radioactive and conventional industries

    The industrial accidents happened in the last years, particularly in the eighty's decade, had contributed in a significant way to call the attention to government authorities, industry and society as a whole, demanding mechanisms for preventing episodes that could affect people's safety and environment quality. Techniques and methods already thoroughly used in the nuclear, aeronautic and war industries were then adapted for performing analysis and evaluation of the risks associated to other industrial activities, especially in the petroleum, chemistry and petrochemical areas. Some models for analyzing the consequences of accidents involving fire and explosion, used in the licensing processes of nuclear and radioactive facilities, are presented in this paper. These models have also application in the licensing of conventional industrial facilities. (author)

  10. Nuclear accidents at the Fukushima Dai-ichi power plant. History, events and consequences

    Written few weeks after the accident, this article first recalls the circumstances (earthquake and tsunami), and then describes the accidental process within the primary vessels of the Fukushima Dai-ichi number 1, 2 and 3 reactors. The author then describes the interventions which aimed at cooling these three reactors, the problem faced for the storage of used fuels, and then the sequence of accidents: loss of cooling means leading to an explosion, problems faced in the different storage pools. He describes the various steps of recovery (primary cooling, electricity supply), discusses the consequences in terms of radioactivity releases in the plant environment with a comparison with Chernobyl, and also in terms of nature and quantity of radioactive elements. He comments radioactivity controls and measurements, evacuation measures, measurements performed by the IAEA, measurements of sea radioactivity, and the establishment of maps of ground radioactivity around the plant. He discusses the perspectives associated with these measurements for the surroundings of the Fukushima site

  11. Consequences of the Chernobyl reactor accident with respect to the feeding of infants

    In view of the persisting and understandable fear of parents with regard to radioactivity in the food of their babies as a consequence of the Chernobyl reactor accident, the Commission on Nutrition of the Deutsche Gesellschaft fuer Kinderheilkunde (German Society of Pediatrics) and the Strahlenschutzkommission have published a statement. According to this statement, the maximum permissible level of radioactivity in commercial baby food has been fixed by the EC to be 370 Bq/kg. The dietetic food industry itself has fixed a maximum for its products which is only a tenth of the radioactivity level permitted by the EC directive. The milk powders for infants tested since the reactor accident contained no measurable radioactivity or only very low amounts of Cs 134 or Cs 137, correspondung to a maximum of 25 Bq/kg in the product. Late damage to health is not to be expected. (orig./ECB)

  12. [Thrombosis and post-thrombotic syndrome as a consequence of an accident].

    Wahl, U; Hirsch, T

    2015-10-01

    Phlebothromboses represent alarming complications in accident victims since they can cause fatal pulmonary embolisms. More than half of those affected also develop post-thrombotic syndrome in the course of the illness. In addition to making clinical assessments, the traumatologist should also have fundamental knowledge about diagnostic methods and be familiar with interpreting internal findings. Colour-coded duplex sonography plays a central role in diagnosing thrombosis and in assessing functional limitations. Further information can be gathered from various phlebological procedures. The expert evaluation of the immediate, as well as the long-term consequences of an accident frequently require leg swelling to be classified. It is not uncommon for post-thrombotic syndrome to be diagnosed for the first time during this process. An additional vascular appraisal is often required. An appreciation of social-medical and insurance-related aspects means a high degree of responsibility is placed on the expert. PMID:26377807

  13. Depressurization as an accident management strategy to minimize the consequences of direct containment heating

    Hanson, D.J.; Golden, D.W.; Chambers, R.; Miller, J.D.; Hallbert, B.P.; Dobbe, C.A. (EG and G Idaho, Inc., Idaho Falls, ID (USA))

    1990-10-01

    Probabilistic Risk Assessments (PRAs) have identified severe accidents for nuclear power plants that have the potential to cause failure of the containment through direct containment heating (DCH). Prevention of DCH or mitigation of its effects may be possible using accident management strategies that intentionally depressurize the reactor coolant system (RCS). The effectiveness of intentional depressurization during a station blackout TMLB' sequence was evaluated considering the phenomenological behavior, hardware performance, and operational performance. Phenomenological behavior was calculated using the SCDAP/RELAP5 severe accident analysis code. Two strategies to mitigate DCH by depressurization of the RCS were considered. One strategy, called early depressurization, assumed that the reactor head vent and pressurizer power-operated relief valves (PORVs) were latched open at steam generator dryout. The second strategy, called late depression, assumed that the head vent and PORVs were latched open at a core exit temperature of {approximately}922 K (1200{degree}F). Depressurization of the RCS to a low value that may mitigate DCH was predicted prior to reactor pressure vessel breach for both early and late depressurization. The strategy of late depressurization is preferred over early depressurization because there are greater opportunities to recover plant functions prior to core damage and because failure uncertainties are lessened. 22 refs., 38 figs., 6 tabs.

  14. Depressurization as an accident management strategy to minimize the consequences of direct containment heating

    Probabilistic Risk Assessments (PRAs) have identified severe accidents for nuclear power plants that have the potential to cause failure of the containment through direct containment heating (DCH). Prevention of DCH or mitigation of its effects may be possible using accident management strategies that intentionally depressurize the reactor coolant system (RCS). The effectiveness of intentional depressurization during a station blackout TMLB' sequence was evaluated considering the phenomenological behavior, hardware performance, and operational performance. Phenomenological behavior was calculated using the SCDAP/RELAP5 severe accident analysis code. Two strategies to mitigate DCH by depressurization of the RCS were considered. One strategy, called early depressurization, assumed that the reactor head vent and pressurizer power-operated relief valves (PORVs) were latched open at steam generator dryout. The second strategy, called late depression, assumed that the head vent and PORVs were latched open at a core exit temperature of ∼922 K (1200 degree F). Depressurization of the RCS to a low value that may mitigate DCH was predicted prior to reactor pressure vessel breach for both early and late depressurization. The strategy of late depressurization is preferred over early depressurization because there are greater opportunities to recover plant functions prior to core damage and because failure uncertainties are lessened. 22 refs., 38 figs., 6 tabs

  15. Consequence analysis

    The objectives of this paper are to: Provide a realistic assessment of consequences; Account for plant and site-specific characteristics; Adjust accident release characteristics to account for results of plant-containment analysis; Produce conditional risk curves for each of five health effects; and Estimate uncertainties

  16. Radiological and dosimetric consequences in case of nuclear accident: taking them into account within the security approach and protection challenges

    This report first proposes a presentation of the 'defence in depth' concept which comprises five as much as possible independent levels: preventing operation anomalies and system failures, maintaining the installation within the authorized domain, controlling accidents within design hypotheses, preventing the degradation of accidental conditions and limiting consequences of severe accidents, limiting radiological consequences for population in case of important releases. Then, after a description of a release atmospheric dispersion and of its consequences, this report describes the consequences of two accident scenarios. The first accident is a failure of steam generator tubes, and the second a loss of primary coolant. It notably indicates the main released radionuclides, exposure levels at different distance for a given set of dispersion conditions

  17. Consequence Analysis of Release from KN-18 Cask during a Severe Transportation Accident

    Lim, Heoksoon; Bhang, Giin; Na, Janghwan; Ban, Jaeha; Kim, Myungsu [KAERI, Daejeon (Korea, Republic of)

    2015-05-15

    Korea Hydro and Nuclear Power (KHNP) has launched a project entitled 'Development of APR1400 Physical Protection System Design' and conducting a new conceptual physical protection system(PPS) design. One of mayor contents is consequence analysis for spent nuclear fuel cask. Proper design of physical protection system for facilities and storage and transformation involving nuclear and radioactive material requires the quantification of potential consequence from prescribed sabotage and theft scenarios in order to properly understand the level of PPS needed for specific facilities and materials. An important aspect of the regulation of the nuclear industry is assessing the risk to the public and the environment from a release of radioactive material produced by accidental or intentional scenarios. This paper describes the consequence analysis methodology, structural analysis for KN-18 cask and results of release from the cask during a severe transportation accident. Accident during spent fuel cask transportation was numerically calculated for KN-18, and showed the integrity of the fuel assemblies and cask itself was unharmed on a scenario that is comparable to state of art NRC research. Even assumption of leakage as a size of 1 x 10''2 mm''2 does not exceed for a certain criteria at any distance.

  18. Economic consequences of the Chernobyl accident in Norway in 1986 and 1987

    In the accident consequence assessment (ACA) area there is extensive cooperation between the Nordic countries (Denmark, Finland, Norway, and Sweden), performed within the Nordic Safety Program, and partially funded by the Nordic Council of Ministers, via the Nordic Liaison Committee for Atomic Energy. One of the 17 projects in the ACA-related program area is concerned with the economic consequences of the Chernobyl accident in Finland, Norway, and Sweden. This paper is limited to describing conditions in Norway. There are areas in Norway where the Chernobyl fallout is >100 kBq/m2, and the total amount of radiocesium deposited over Norway is estimated by the National Institute for Radiation Hygiene to be 6% of the radiocesium released from the reactor. The areas where ground concentrations are highest are mostly in sparsely populated mountain areas. These areas are, however, important in connection with several nutritional pathways, notably, sheep, goats, reindeer, and freshwater fish. The purpose of this paper is to summarize information on mitigating actions and economic consequences of the deposited radioactive materials to Norwegian agriculture in the 1986-87 and 1987-88 slaughtering periods

  19. Consequence Analysis of Release from KN-18 Cask during a Severe Transportation Accident

    Korea Hydro and Nuclear Power (KHNP) has launched a project entitled 'Development of APR1400 Physical Protection System Design' and conducting a new conceptual physical protection system(PPS) design. One of mayor contents is consequence analysis for spent nuclear fuel cask. Proper design of physical protection system for facilities and storage and transformation involving nuclear and radioactive material requires the quantification of potential consequence from prescribed sabotage and theft scenarios in order to properly understand the level of PPS needed for specific facilities and materials. An important aspect of the regulation of the nuclear industry is assessing the risk to the public and the environment from a release of radioactive material produced by accidental or intentional scenarios. This paper describes the consequence analysis methodology, structural analysis for KN-18 cask and results of release from the cask during a severe transportation accident. Accident during spent fuel cask transportation was numerically calculated for KN-18, and showed the integrity of the fuel assemblies and cask itself was unharmed on a scenario that is comparable to state of art NRC research. Even assumption of leakage as a size of 1 x 10''2 mm''2 does not exceed for a certain criteria at any distance

  20. The environmental restoration in the management of radiological accidents with off site consequences

    Radiological accidents are among the potential cases of environmental contamination that could have consequences on the health of the population. These accidents, associated with an increase in the level of radiological exposure surpassing the natural background, have been investigated in greater depth than other conventional accidents. This investigation has included the evaluation of their probability, magnitude and consequences in order to establish safety norms. Nevertheless, the social perception of this type of risk appears to be disproportionately high. The development of a comprehensible and adequate standardized system for the evaluation of the radiological risk and the applicability of corrective actions to reduce this type of risk at local level, will undoubtedly contribute to increase the public confidence in the advised options for the restoration of environments contaminated with the long lived radionuclides. This system should consider the local specificity of each contaminated place, and take into account the associated unwanted consequences for each option. This paper presents the first results of a system to help the decision makers in the quantitative evaluation of the radiological risk produced by long lived radionuclides Cs 137, Cs 134 and Sr 90 spread over urban, agricultural and semi-natural environments and the applicable options to reduce it. The evaluation of these applicable options is made considering the reduction of dose that can be reached, the monetary costs and the significant associated secondary effects if there are any. All these factors are integrated for a time period depending on the half-life of the contaminants and on their strength and distribution on the scenario when intervention is being planned. (authors)

  1. The Fukushima Daiichi Accident. Technical Volume 4/5. Radiological Consequences

    This technical volume describes the consequences associated with radioactivity and radiation from the accident at the Fukushima Daiichi nuclear power plant (NPP) for people and the environment. A number of international organizations have already issued reports on the potential health and environmental consequences of the accident, notably the World Health Organization (WHO) and the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). The intention of the assessments presented in this volume is to build on their work, using more recent data where available. Quantitative information arising from both personal and environmental monitoring has been provided by the Government of Japan. Section 4.1 provides the best estimates of the magnitude and form of radioactive releases during the accident to the atmosphere and directly into the surrounding sea. It also explains the movement of the discharged radionuclides through air and water and the eventual deposition of the atmospheric activity on land in Japan and other countries worldwide, as well as on the open oceans. The goal is to provide a consolidated repository of information on releases to, and levels of radionuclides in, the environment. Some of this information is used in the analyses in subsequent sections of this volume. Section 4.2 gives an overview of exposures to the main groups of emergency workers at the Fukushima Daiichi NPP, to groups of off-site workers and to members of the public. Where sufficient data are available, average effective dose and thyroid equivalent doses derived from personal measurements are compared with the results of previous assessments for specific locations, population groups and time periods. Section 4.3 summarizes relevant aspects of the system of radiation protection in place at the time of the accident. It includes an overview of the legislation and guidance used to implement the radiation protection framework in Japan. This section also provides a

  2. Health effects model for nuclear power plant accident consequence analysis. Part I. Introduction, integration, and summary. Part II. Scientific basis for health effects models

    Evans, J.S.; Moeller, D.W.; Cooper, D.W.

    1985-07-01

    Analysis of the radiological health effects of nuclear power plant accidents requires models for predicting early health effects, cancers and benign thyroid nodules, and genetic effects. Since the publication of the Reactor Safety Study, additional information on radiological health effects has become available. This report summarizes the efforts of a program designed to provide revised health effects models for nuclear power plant accident consequence modeling. The new models for early effects address four causes of mortality and nine categories of morbidity. The models for early effects are based upon two parameter Weibull functions. They permit evaluation of the influence of dose protraction and address the issue of variation in radiosensitivity among the population. The piecewise-linear dose-response models used in the Reactor Safety Study to predict cancers and thyroid nodules have been replaced by linear and linear-quadratic models. The new models reflect the most recently reported results of the follow-up of the survivors of the bombings of Hiroshima and Nagasaki and permit analysis of both morbidity and mortality. The new models for genetic effects allow prediction of genetic risks in each of the first five generations after an accident and include information on the relative severity of various classes of genetic effects. The uncertainty in modeloling radiological health risks is addressed by providing central, upper, and lower estimates of risks. An approach is outlined for summarizing the health consequences of nuclear power plant accidents. 298 refs., 9 figs., 49 tabs.

  3. Health effects model for nuclear power plant accident consequence analysis. Part I. Introduction, integration, and summary. Part II. Scientific basis for health effects models

    Analysis of the radiological health effects of nuclear power plant accidents requires models for predicting early health effects, cancers and benign thyroid nodules, and genetic effects. Since the publication of the Reactor Safety Study, additional information on radiological health effects has become available. This report summarizes the efforts of a program designed to provide revised health effects models for nuclear power plant accident consequence modeling. The new models for early effects address four causes of mortality and nine categories of morbidity. The models for early effects are based upon two parameter Weibull functions. They permit evaluation of the influence of dose protraction and address the issue of variation in radiosensitivity among the population. The piecewise-linear dose-response models used in the Reactor Safety Study to predict cancers and thyroid nodules have been replaced by linear and linear-quadratic models. The new models reflect the most recently reported results of the follow-up of the survivors of the bombings of Hiroshima and Nagasaki and permit analysis of both morbidity and mortality. The new models for genetic effects allow prediction of genetic risks in each of the first five generations after an accident and include information on the relative severity of various classes of genetic effects. The uncertainty in modeloling radiological health risks is addressed by providing central, upper, and lower estimates of risks. An approach is outlined for summarizing the health consequences of nuclear power plant accidents. 298 refs., 9 figs., 49 tabs

  4. An assessment of the consequences of the Greek Research Reactor's design basis accident: sensitivity to the meteorological record

    The sensitivity of the Greek Research Reactor's design basis accident consequences to the meteorological record, as far as Athens population is concerned, is assessed in this report. Meteorological data of six years of the National Observatory of Athens are analyzed and utilized in the accident consequence calculation model by using weather categories. The results of the present analysis indicate that the meteorological record does not have a significant impact on predicted consequences, which in turn indicates that the utilization of a substitute meteorological record from a nearby meteorological station instead of the reactor's site record could be acceptable for performing consequence analyses. (author)

  5. Modeling the consequences of hypothetical accidents for the Titan II system

    Calculations have been made with the Atmospheric Release Advisory Capability (ARAC) suite of three-dimensional transport and diffusion codes MATHEW/ADPIC to assess the consequences of severe, hypothetical accident scenarios. One set of calculations develops the integrated dose and surface deposition patterns for a non-nuclear, high explosive detonation and dispersal of material. A second set of calculations depicts the time integrated dose and instantaneous concentration patterns for a substantial, continuous leak of the missile fuel oxidizer converted to nitrogen dioxide (NO2). The areas affected and some of the implications for emergency response management are discussed

  6. UFOMOD - program to calculate the radiological consequences of reactor accidents within risk studies

    The FORTRAN-IV computer code UFOMOD calculates the radiological consequences of reactor accidents for risk studies, namely early deaths, latent cancer deaths and genetic significant doses. Different models for the atmospheric transport and deposition, the dose calculation, the countermeasures and the injuries are used to calculate individual and collective injury. Up to 54 radionuclides, 10 release categories, 4 meteorological zones, 10 population distributions per zone with up to 36 sectors and 50 rings, and 115 weather sequences per zone may be used. The deterministic results are combined together with the respective probabilities and frequencies to give complementary cumulative frequency distributions. This report describes the computer code and its input and output. (orig.)

  7. Calculations of reactor-accident consequences, Version 2. CRAC2: computer code user's guide

    The CRAC2 computer code is a revision of the Calculation of Reactor Accident Consequences computer code, CRAC, developed for the Reactor Safety Study. The CRAC2 computer code incorporates significant modeling improvements in the areas of weather sequence sampling and emergency response, and refinements to the plume rise, atmospheric dispersion, and wet deposition models. New output capabilities have also been added. This guide is to facilitate the informed and intelligent use of CRAC2. It includes descriptions of the input data, the output results, the file structures, control information, and five sample problems

  8. Medico-demographic criteria in estimating the consequences of the Chernobyl accident

    Correct comparison of population statistics in affected and unaffected areas prior to and after the accident allows to detect any noticeable deviations in basic medico-demographic parameters in contaminated territories from common trends. In view of that when in 1990 in Nuclear Safety Institute a start has been made on construction of an information support system for government and regional executives to overcome the consequences of the Chernobyl disaster a specialized data bank on demography and medical statistics (MDBD) was created. 12 refs, 7 figs, 8 tabs

  9. Functional status of thyroid of Chernobyl accident consequences liquidators after 10 years after disaster

    Analysis of Chernobyl accident consequences liquidators' complaints is carried out and their clinical surveillance is conducted as well. Pronounced disorders of neuro-immune-endocrine system of the liquidators majority and ahill reflex latency half-period prolongation have been observed. By data of ultrasonic study the majority of examined ones have thyroid hyperplasia without features of chronic autoimmune inflammation and formation of adenomatous knots. Thyroid levels of hormone concentration are reduced. There is direct dependence between hormones levels and irradiation dose. The is concluded, that in delayed period after irradiation by low doses the hypo-function status of thyroid is observing

  10. Development of an accident consequence analysis program based on the object oriented programming technique

    The KAERI accident consequence analysis program KAPAC is being developed on the basis of reusable objects in PPAM (platform for the development of plant analysis and management codes). Development of PPAM is being conducted at the Korea Atomic Energy Research Institute (KAERI) in order to be able to provide portability and reusability of computer codes, and consistent user interface in developing software with the use of object oriented programming (OOP) under a Microsoft Windows environment. By constructing the platform, software development can benefit from a shorter development cycle and an easier validation and verification process. 1 ref., 2 figs

  11. Hypertension and left ventricular hypertrophy in liquidators of consequences of the Chernobyl nuclear accident

    Echocardiography was used for the study of prevalence of left ventricular hypertrophy in 839 liquidators of consequences of the Chernobyl accident. Prevalence of left ventricular hypertrophy (left ventricular myocardial mass 134 g/m2) was 10.3, 13.4 and 22.5 % in liquidators with normal blood pressure, borderline hypertension and hypertension, respectively. Liquidators with normal blood pressure had significantly greater left ventricular myocardial mass than normotensive men from general population while liquidators and non liquidators with hypertension had equal values of this parameter

  12. The accident in Fukushima. Preliminary report on the accident progress in the nuclear power plants as a consequence of the earth quake on 11th March 2011

    The preliminary report on the accident progress in the nuclear power plants as a consequence of the earth quake on 11th March 2011 describes the chronologic sequence of the accident in the different units of the power plant. The measures for mitigation of the accident impact at the site of Fukushima Daiichi and Fukushima Daini included the efforts to reach and maintain stable plant conditions. The issue radiological situation includes an estimation of the air-borne radionuclide release, the contamination of the environment and the sea water, measures for protection of the public. The lessons learned following the NISA and IAEA fact finding missions and the open questions are summarized.

  13. Epidemiological studies in Russia about the consequences of the Chernobyl APS accident

    Ryabzev, I.A. [Institute of Problem of Ecology and Evolution, Russian Academy of Sciences, Moscow (Russian Federation)

    1998-03-01

    The final purpose of all efforts to study and mitigate the consequences of the accident at the 4th reactor of the Chernobyl atomic power station (ChAPS) is protection of health of the people who were more or less exposed to radiation action. This situation has not analogs in terms of scale and character. Certain experience was accumulated earlier through the studies of biological and medical effects of atomic bombing in Hiroshima and Nagasaki, other radiation catastrophes, diagnostic and therapeutic application of radiation, and the control of health state of professionals in atomic industries. However, these experiences can be used just partially in the assessment and the forecast of possible negative after-effects of the Chernobyl accident for the present and future generations. The long-term irradiation of a lage number of population at low doses is to be considered the principal peculiarity of the Chernobyl accident. The medical activities are complicated significantly by the absence of verifiable individual dosimetric information, natural or forced migration of the population, insufficient development of radiation epidemiology, complicated social-economic situation in the country, and other factors which are inevitable at large-scaled catastrophes. Besides, many fundamental questions related to biological effects of action of low doses of ionizing radiation are still being studied. (J.P.N.)

  14. Knowledge resources on the Chernobyl accident and its consequences in the INIS Database

    Literature on the Chernobyl accident and its consequences is an important subject covered by the International Nuclear Information System (INIS) Database. The INIS Database contains 19872 bibliographic records and 8400 full text documents on this subject from 1986 up to 04/2005. A bibliometric study of these records was made to generate statistical summaries that characterise, in general terms, the intellectual content of the records and the nature of the records in terms of its major bibliographic attributes. Environmental aspects and human health constitute the two dominant subjects with a respective contribution of 49% and 38%. The rest is evenly divided among legal aspects, reactor safety and socio-economic impacts of the accident. The three countries that are most affected by the accident, namely Ukraine, Russian Federation and Belarus contributed 44% of the total input. 57% of the literature analysed are conference papers and reports while 25% are journal articles. Most of the documents were written in English (47%) and in Russian (36%). Seven percent of the publications were written in German. (author)

  15. Source term and radiological consequence evaluation for nuclear accidents using a 'hand type' methodology

    In the last decades, hand type calculations have been replaced by computerized solutions, which are much more accurate, but the preparation of an input to run the code can be a time consuming process and can require a laborious work. This is why, a place for hand calculation based on nomograms still exist in some areas. An example is emergency response to an accidental release of radioactive contaminants when the health of persons close to the accident site might be at risk. In this case, results from computerized accident consequences assessment models may be delayed due to the equipment malfunction or the time required developing minimal input files and performing the calculations (typically more than five minutes). A simple nomogram (developed using computerized dispersion model calculations) can provide dispersion and dose estimates within a minute. The paper presents the methodology used for these 'hand type' calculation and the nomograms, figures and tables used to evaluate the dose to an individual close to the release point. In order to illustrate the use of methodology, a hypothetical severe accident scenario involving 14-MW INR-TRIGA research reactor was considered. (authors)

  16. Mitigation of sodium-cooled fast reactor severe accident consequences using inherent safety principles

    Full text: Sodium-cooled fast reactors are designed to have a high level of safety. Events of high probability of occurrence are typically handled without consequence through reliable engineering systems and good design practices. For accidents of lower probability, the initiating events are characterized by larger and more numerous challenges to the reactor system, such as failure of one or more major engineered systems and can also include a failure to scram the reactor in response. As the initiating conditions become more severe, they have the potential for creating serious consequences of potential safety significance, including fuel melting, fuel pin disruption and recriticality. If the progression of such accidents is not mitigated by design features of the reactor, energetic events and dispersal of radioactive materials may result. In the United States, accidents which have the potential for severe consequences usually are of probability less than 1 x 10-4 per reactor year, intended to satisfy the U.S. Nuclear Regulatory Commission (NRC) goal of limiting accidents with any fuel melting to such low probabilities. Such severe accidents include the category of Anticipated Transient Without Scram (ATWS) events mentioned above. Three accidents are usually analyzed to evaluate the reactor response in these cases; the unprotected (unscrammed) loss-of-flow (ULOF), where pumping power is lost and the pumps coast down, reducing coolant flow through the reactor core; the unprotected transient overpower (UTOP), where a control rod is inadvertently withdrawn from the core; and the unprotected loss-of-heat-sink (ULOHS), where the steam generator is isolated from the reactor in response to a turbine trip. For each of these accidents, there are several approaches that can be used to mitigate the consequences of such severe accident initiators, which typically include fuel pin failures and core disruption. One approach is to increase the reliability of the reactor protection

  17. Fukushima, one year later. Initial analyses of the accident and its consequences

    The earthquake of magnitude 9 of March 11, 2011 with an epicenter 80 km east of the Japanese island of Honshu, and the subsequent tsunami, severely affected the region of Tohoku, with major consequences for its population and infrastructure. Devastating the site of the Fukushima Dai-ichi nuclear power plant, these natural events were the cause of the core meltdowns of three nuclear reactors and the loss of cooling of several spent fuel pools. Explosions also occurred in reactor buildings 1 through 4 due to hydrogen produced during fuel degradation. Very significant radioactive releases into the environment took place. The accident was classified level 7 on the International Nuclear Event Scale (INES). This report provides an assessment and perspective on the information gathered by IRSN during the first twelve months following the disaster in an effort to understand the condition of the installations, evaluate the releases and analyze and evaluate the consequences of the accident on workers and the impact on the population and the environment. On the basis of available information, the report provides an initial analysis of the chain of events. It should be noted that a year after the accident, the full sequence of events is still not understood. Operating experience feedback from the 1979 Three Mile Island accident in the United States, in which reactor core damage was not confirmed until 1986, suggests that it may be several years before a detailed scenario can be constructed of the accident that led to radioactive releases. It will require access to the damaged installations. The situation at the site remains dangerous (reactor pressure vessels and containments are not leak-tight, diffuse releases, etc.). If it has significantly improved as a result of the significant resources deployed by the Tokyo Electro Power Company (TEPCO) to regain control of the installations, this effort must continue over the long term to begin evacuation of fuel from pools (in two

  18. A review of the Melcor Accident Consequence Code System (MACCS): Capabilities and applications

    MACCS was developed at Sandia National Laboratories (SNL) under U.S. Nuclear Regulatory Commission (NRC) sponsorship to estimate the offsite consequences of potential severe accidents at nuclear power plants (NPPs). MACCS was publicly released in 1990. MACCS was developed to support the NRC's probabilistic safety assessment (PSA) efforts. PSA techniques can provide a measure of the risk of reactor operation. PSAs are generally divided into three levels. Level one efforts identify potential plant damage states that lead to core damage and the associated probabilities, level two models damage progression and containment strength for establishing fission-product release categories, and level three efforts evaluate potential off-site consequences of radiological releases and the probabilities associated with the consequences. MACCS was designed as a tool for level three PSA analysis. MACCS performs probabilistic health and economic consequence assessments of hypothetical accidental releases of radioactive material from NPPs. MACCS includes models for atmospheric dispersion and transport, wet and dry deposition, the probabilistic treatment of meteorology, environmental transfer, countermeasure strategies, dosimetry, health effects, and economic impacts. The computer systems MACCS is designed to run on are the 386/486 PC, VAX/VMS, E3M RISC S/6000, Sun SPARC, and Cray UNICOS. This paper provides an overview of MACCS, reviews some of the applications of MACCS, international collaborations which have involved MACCS, current developmental efforts, and future directions

  19. Research activities about the radiological consequences of the Chernobyl NPS accident and social activities to assist the sufferers by the accident

    The 12th anniversary is coming soon of the accident at the Chernobyl nuclear power station in the former USSR on April 26, 1986. Many issues are, however, still unresolved about the radiological impacts on the environment and people due to the Chernobyl accident. This report contains the results of an international collaborative project about the radiological consequences of the Chernobyl accident, carried out from November 1995 to October 1997 under the research grant of the Toyota foundation. Collaborative works were promoted along with the following 5 sub-themes: 1) General description of research activities in Russia, Belarus and Ukraine concerning the radiological consequences of the accident. 2) Investigation of the current situation of epidemiological studies about Chernobyl in each affected country. 3) Investigation of acute radiation syndrome among inhabitants evacuated soon after the accident from the 30 km zone around the Chernobyl NPS. 4) Overview of social activities to assist the sufferers by the accident in each affected country. 5) Preparation of special reports of interesting studies being carried out in each affected country. The 27 papers are indexed individually. (J.P.N.)

  20. Assessment of Radiological and Economic Consequences of a Hypothetical Accident for ETRR-2, Egypt Utilizing COSYMA Code

    A comprehensive probabilistic study of an accident consequence assessment (ACA) for loss of coolant accident (LOCA) has accomplished to the second research reactor ETRR-2, located at Inshas Nuclear Research Center, Cairo, Egypt. PC-COSYMA, developed with the support of European Commission, has adopted to assess the radiological and economic consequences of a proposed accident. The consequences of the accident evaluated in case of early and late effects. The effective doses and doses in different organs carried out with and without countermeasures. The force mentioned calculations were required the following studies: the core inventory due to the hypothetical accident, the physical parameters of the source term, the hourly basis meteorological parameters for one complete year, and the population distribution around the plant. The hourly stability conditions and height of atmospheric boundary layers (ABL) of the concerned site were calculated. The results showed that, the nuclides that have short half-lives (few days) give the highest air and ground concentrations after the accident than the others. The area around the reactor requires the early and late countermeasures action after the accident especially in the downwind sectors. Economically, the costs of emergency plan are effectively high in case of applying countermeasures but countermeasures reduce the risk effects

  1. Techniques and decision making in the assessment of off-site consequences of an accident in a nuclear facility

    This Guide is intended to complement the IAEA's existing technical guidance on emergency planning and preparedness by providing information and practical guidance related to the assessment of off-site consequences of an accident in a nuclear or radioactive materials installation and to the decision making process in implementing protective measures. This Guide contains information on emergency response philosophy, fundamental factors affecting accident consequences, principles of accident assessment, data acquisition and handling, systems, techniques and decision making principles. Many of the accident assessment concepts presented are considerably more advanced than some of those that now pertain in most countries. They could, if properly interpreted, developed and applied, significantly improve emergency response in the early and intermediate phases of an accident. Furthermore, they are considered to be applicable to a broad range of serious nuclear accidents and radiological emergencies. The extent of their application is governed by both the scale of the accident and by the availability of preplanned resources for accident assessment and emergency response. 68 refs, 28 figs, 14 tabs

  2. Applications of Probabilistic Consequence Assessment Uncertainty Analysis for Plant Management (invited paper)

    Probabilistic Consequence Assessment (PCA) models describe the dispersion of released radioactive materials and predict the resulting interaction with and influence on the environment and man. Increasing use is being made of PCA tools as an input to the evaluation and improvement of safety for nuclear installations. The nature and extent of the assessment performed varies considerably according to its intended purpose. Nevertheless with the increasing use of such techniques, greater attention has been given to the reliability of the methods used and the inherent uncertainty associated with their predictions. Uncertainty analyses can provide the decision-maker with information to quantify how uncertain the answer is and what drives that uncertainty. They often force a review of the baseline assumptions for any PCA methodology and provide a benchmark against which the impact of further changes in models and recommendations can be compared. This process provides valuable management information to help prioritise further actions or research. (author)

  3. Qualification and application of nuclear reactor accident analysis code with the capability of internal assessment of uncertainty

    This paper presents an independent qualification of the CIAU code ('Code with the capability of - Internal Assessment of Uncertainty') which is part of the internal uncertainty evaluation process with a thermal hydraulic system code on a realistic basis. This is done by combining the uncertainty methodology UMAE ('Uncertainty Methodology based on Accuracy Extrapolation') with the RELAP5/Mod3.2 code. This allows associating uncertainty band estimates with the results obtained by the realistic calculation of the code, meeting licensing requirements of safety analysis. The independent qualification is supported by simulations with RELAP5/Mod3.2 related to accident condition tests of LOBI experimental facility and to an event which has occurred in Angra 1 nuclear power plant, by comparison with measured results and by establishing uncertainty bands on safety parameter calculated time trends. These bands have indeed enveloped the measured trends. Results from this independent qualification of CIAU have allowed to ascertain the adequate application of a systematic realistic code procedure to analyse accidents with uncertainties incorporated in the results, although there is in an evident need of extending the uncertainty data base. It has been verified that use of the code with this internal assessment of uncertainty is feasible in the design and license stages of a NPP. (author)

  4. Qualification and application of nuclear reactor accident analysis code with the capability of internal assessment of uncertainty

    This thesis presents an independent qualification of the CIAU code ('Code with the capability of - Internal Assessment of Uncertainty') which is part of the internal uncertainty evaluation process with a thermal hydraulic system code on a realistic basis. This is done by combining the uncertainty methodology UMAE ('Uncertainty Methodology based on Accuracy Extrapolation') with the RELAP5/Mod3.2 code. This allows associating uncertainty band estimates with the results obtained by the realistic calculation of the code, meeting licensing requirements of safety analysis. The independent qualification is supported by simulations with RELAP5/Mod3.2 related to accident condition tests of LOBI experimental facility and to an event which has occurred in Angra 1 nuclear power plant, by comparison with measured results and by establishing uncertainty bands on safety parameter calculated time trends. These bands have indeed enveloped the measured trends. Results from this independent qualification of CIAU have allowed to ascertain the adequate application of a systematic realistic code procedure to analyse accidents with uncertainties incorporated in the results, although there is an evident need of extending the uncertainty data base. It has been verified that use of the code with this internal assessment of uncertainty is feasible in the design and license stages of a NPP. (author)

  5. Reactor safety study. An assessment of accident risks in U.S. commercial nuclear power plants. Appendix VI. Calculation of reactor accident consequences

    Information is presented concerning the radioactive releases from the containment following accidents; radioactive inventory of the reactor core; atmospheric dispersion; reactor sites and meteorological data; radioactive decay and deposition from plumes; finite distance of plume travel; dosimetric models; health effects; demographic data; mitigation of radiation exposure; economic model; and calculated results with consequence model

  6. Reactor safety study. An assessment of accident risks in U. S. commercial nuclear power plants. Appendix VI. Calculation of reactor accident consequences. [PWR and BWR

    1975-10-01

    Information is presented concerning the radioactive releases from the containment following accidents; radioactive inventory of the reactor core; atmospheric dispersion; reactor sites and meteorological data; radioactive decay and deposition from plumes; finite distance of plume travel; dosimetric models; health effects; demographic data; mitigation of radiation exposure; economic model; and calculated results with consequence model.

  7. The radiological consequences of degraded core accidents for the Sizewell PWR The impact of adopting revised frequencies of occurrence

    Kelly, G N

    1983-01-01

    The radiological consequences of degraded core accidents postulated for the Sizewell PWR were assessed in an earlier study and the results published in NRPB-R137. Further analyses have since been made by the Central Electricity Generating Board (CEGB) of degraded core accidents which have led to a revision of their predicted frequencies of occurrence. The implications of these revised frequencies, in terms of the risk to the public from degraded core accidents, are evaluated in this report. Increases, by factors typically within the range of about 1.5 to 7, are predicted in the consequences, compared with those estimated in the earlier study. However, the predicted risk from degraded core accidents, despite these increases, remains exceedingly small.

  8. Radiological consequences of a propagated fire accident in a radiochemical separations facility

    A radiological consequence analysis of a propagated fire accident in a Savannah River Site (SRS) radiochemical separations facility has been performed. This analysis supports the safety documentation for the SRS plutonium reprocessing facility. Included are the evaluation of the doses resulting from the exposure to the radioactive airborne release for co-located facility worker and the off-site individual receptors. Atmospheric dispersion calculations using qualified five-year (1987-1991) meteorological data were performed with the computer code AXAIR89Q, a validated computer code for radiological dose calculations. Radioactive source term estimates and assumptions of material composition and isotope distribution were based on existing permissible storage levels as defined in approved safety documentation. The fire accident scenario assumes that the fire propagates in the entire facility on four structural levels. Approximately 97% of the radioactive materials released occurs from levels three and four of the facility, which are not included in the ventilation pathway to the sand trap filter. Radiological analysis results indicate that the doses to co-located worker and off-site individual receptors are equal to 4.4 rem and 3.3 rem, respectively. Accident mitigators that were identified include provision for filtration capacity from levels three and four of the facility, and relocation of stored radioactive materials. Provision for filtration capacity would reduce the source term from an unfiltered activity of 53.6 Ci to a filtered activity of 2.0 Ci. Relocation of stored radioactive materials would result in a source term reduction from 53.6 Ci to 20 Ci. Limitations exist, however, that may make implementation of the identified mitigators difficult or prohibitive

  9. Analysis for mechanical consequences of a core disruptive accident in Prototype Fast Breeder Reactor

    The mechanical consequences of a core disruptive accident (CDA) in a fast breeder reactor are described. The consequences are development of deformations and strains in the vessels, intermediate heat exchangers (IHX) and decay heat exchangers (DHX), impact of sodium slug on the bottom surface of the top shield, sodium release to reactor containment building through top shield penetrations, sodium fire and consequent temperature and pressure rise in reactor containment building (RCB). These are quantified for 500 MWe Prototype Fast Breeder Reactor (PFBR) for a CDA with 100 MJ work potential. The results are validated by conducting a series of experiments on 1/30 and 1/13 scaled down models with increasing complexities. Mechanical energy release due to nuclear excursion is simulated by chemical explosion of specially developed low density explosive charge. Based on these studies, structural integrity of primary containment, IHX and DHX is demonstrated. The sodium release to RCB is 350 kg which causes pressure rise of 12 kPa in RCB. (author)

  10. Application of Bayesian nonparametric models to the uncertainty and sensitivity analysis of source term in a BWR severe accident

    A full-scope method is constructed to reveal source term uncertainties and to identify influential inputs during a severe accident at a nuclear power plant (NPP). An integrated severe accident code, MELCOR Ver. 1.8.5, is used as a tool to simulate the accident similar to that occurred at Unit 2 of the Fukushima Daiichi NPP. In order to figure out how much radioactive materials are released from the containment to the environment during the accident, Monte Carlo based uncertainty analysis is performed. Generally, in order to evaluate the influence of uncertain inputs on the output, a large number of code runs are required in the global sensitivity analysis. To avoid the laborious computational cost for the global sensitivity analysis via MELCOR, a surrogate stochastic model is built using a Bayesian nonparametric approach, Dirichlet process. Probability distributions derived from uncertainty analysis using MELCOR and the stochastic model show good agreement. The appropriateness of the stochastic model is cross-validated through the comparison with MELCOR results. The importance measure of uncertain input variables are calculated according to their influences on the uncertainty distribution as first-order effect and total effect. The validity of the present methodology is demonstrated through an example with three uncertain input variables. - Highlights: • A method of source term uncertainty and sensitivity analysis is proposed. • Source term in Fukushima Daiichi NPP severe accident is demonstrated. • Uncertainty distributions of source terms show non-standard shapes. • A surrogate model for integrated code is constructed by using Dirichlet process. • Importance ranking of influential input variables is obtained

  11. Optimum modellings of atmospheric diffusion of radioactive effluents and exposure doses in the accident consequence assessment (Level 3 PSA)

    Atmospheric diffusion and exposure strongly dependent on the environment were firstly considered in the full spectrum of accident consequence assessment to establish based on Korean conditions. An optimum weather category based on Korean climate and site-specific meteorology of Kori region was established by statistical analysis of measured data for 10 years. And a trajectory model was selected as the optimal one in the ACA by reviewing several existing diffusion models. Following aspects were considered in this selection as availability of meteorological data, ability to treat the change to wind direction, easy applicability of the model, and restriction of CPU time and core memory in current computers. Numerical integration method of our own was selected as the optimal dose assessment tool of external exposure. Unit dose rate was firstly computed with this method as the function of energy level of radionuclide, size of lattice, and distance between source and receptor, and then the results were rearranged as the data library for the rapid access to the ACA run. Dynamic ecosystem modelling has been done in order to estimate the seasonal variation of radioactivity for the assessment of ingestion exposure, considering Korean ingestion behavior, agricultural practice and the transportation. There is a lot of uncertainty in a countermeasure model due to the assumed values of parameters such as fraction of population with different shielding factor and driving speed. A new countermeasure model was developed using the concept of fuzzy set theory, since it provided the mathematical tools which could characterize the uncertainty involved in countermeasure modelling. (Author)

  12. Agroindustrial production sphere - radiological consequences of the Chernobyl accident and the chief protective measures

    As a result of the Chernobyl accident, fallout of radionuclides has occurred on farm lands, and the contaminated production of the agroindustrial complex has become a source of additional irradiation of the population. The contribution of the irradiation associated with the consumption of locally produced food products was quite significant, and led to the implementation of protective measures in the agroindustrial production sphere. It should be noted that irradiation of people owing to the consumption of contaminated agricultural products is more easily regulated than external irradiation. For this reason, the decrease in the total dose load is largely determined by the possibilities of restricting the internal irradiation dose to the population from the consumption of food products. The paper discusses radiological conditions in the agroindustrial production sphere in the region of the accident; intake of radionuclides by agricultural plants through leaves; distribution and form of 137Cs in soils; uptake of radionuclides by plants from the soil, animal husbandry aspects of the migration of radionuclides and their biological action; and organizational measures of the USSR for mitigating the consequences

  13. Chernobyl NPP accident consequences cleaning up participants in Ukraine -health status epidemiologic study main results

    The Epidemiologic Studies System for Chernobyl NPP Accident consequences cleaning up participants (CNPP ACCP) health status was worked out and than improving in Ukraine after the CNPP Accident. The State Register of Ukraine both with several other Registers are the organizational, methodological and informational basis here. The ACCP health status worsening ,-was registered in dynamics through the post-accidental period i.e. the nervous system, digestive system, blood circulation system, respiratory system, bone-muscular system, endocrine and genitourinary systems chronic non-tumoral pathology both with mental disorders amount increase. In cohort study the differences of morbidity formation were fixed among emergency workers with different radiation exposure doses. The dependence of leukemia morbidity on presence in 30-km zone duration was noticed, it's access manifested 5 years after the participance in ACC. The ACCP disablement increase with main reason of general somatic diseases, and annual mortality growth are registered. But that doesn't exceed the mortality rate among population of working age in Ukraine

  14. A dynamic food-chain model and program for predicting the radiological consequences of nuclear accident

    A dynamic food-chain model and program, DYFOM-95, for predicting the radiological consequences of nuclear accident has been developed, which is not only suitable to the West food-chain but also to Chinese food chain. The following processes, caused by accident release which will make an impact on radionuclide concentration in the edible parts of vegetable are considered: dry and wet deposition interception and initial retention, translocation, percolation, root uptake and tillage. Activity intake rate of animals, effects of processing and activity intake of human through ingestion pathway are also considered in calculations. The effects of leaf area index LAI of vegetable are considered in dry deposition model. A method for calculating the contribution of rain with different period and different intensity to total wet deposition is established. The program contains 1 main code and 5 sub-codes to calculate dry and wet deposition on surface of vegetable and soil, translocation of nuclides in vegetable, nuclide concentration in the edible parts of vegetable and in animal products and activity intake of human and so on. (24 refs., 9 figs., 11 tabs.)

  15. Agro-industrial sphere-radiological consequence of Chernobyl accident and major safety measures

    The early spring radionuclide fall as a consequence of Chernobyl accident caused air contamination of aerial part of agriculture crop - winter crops, natural and seeded permanent grasses. For other plants the soil and wind contamination are prevailing. After radionuclide fall most of them are concentrated in the soil upper layer. Radionuclide uptake depends on the ratio of their concentration in soils, that is varied due to the soil type. The soil development results in variation of radionuclide migration in the crop. In cattle production two main trends are the most significant: estimation of food contamination (primarily of milk and meat) and analysis of physiological state of animals near NPP. Organization and land-improvement measures permitting a stable agro-industrial functionaing on the contaminated territory are considered

  16. Introductory remarks by the Chairman. [Session 1: Environmental and health consequences of the Chernobyl accident

    Many scientists as well as representatives from UN organizations and governments of affected regions participated in the work of the Chernobyl Forum. Several meetings of the Forum were necessary to initiate the work and monitor the progress of the expert groups. Two expert groups formulated comprehensive reports - one on environmental issues, organized by the IAEA, and one on health issues, organized by the WHO. Experts from throughout the world were invited to contribute to these evaluations. The representatives of governments and the staff of international organizations then reviewed the results of these groups to be sure that the reviews were complete and the evaluations reasonable, so that they could serve as the basis for consensus agreements and effective recommendations for further dealing with the consequences of the accident

  17. Accidental beam loss in superconducting accelerators: Simulations, consequences of accidents and protective measures

    The consequences of an accidental beam loss in superconducting accelerators and colliders of the next generation range from the mundane to rather dramatic, i.e., from superconducting magnet quench, to overheating of critical components, to a total destruction of some units via explosion. Specific measures are required to minimize and eliminate such events as much as practical. In this paper we study such accidents taking the Superconducting Supercollider complex as an example. Particle tracking, beam loss and energy deposition calculations were done using the realistic machine simulation with the Monte-Carlo codes MARS 12 and STRUCT. Protective measures for minimizing the damaging effects of prefire and misfire of injection and extraction kicker magnets are proposed here

  18. Health effects models for off-site radiological consequence analysis on nuclear reactor accidents (II)

    Homma, Toshimitsu [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Takahashi, Tomoyuki [Kyoto Univ., Kumatori, Osaka (Japan). Research Reactor Inst; Yonehara, Hidenori [National Inst. of Radiological Sciences, Chiba (Japan)] [eds.

    2000-12-01

    This report is a revision of JAERI-M 91-005, 'Health Effects Models for Off-Site Radiological Consequence Analysis of Nuclear Reactor Accidents'. This revision provides a review of two revisions of NUREG/CR-4214 reports by the U.S. Nuclear Regulatory Commission which is the basis of the JAERI health effects models and other several recent reports that may impact the health effects models by international organizations. The major changes to the first version of the JAERI health effects models and the recommended parameters in this report are for late somatic effects. These changes reflect recent changes in cancer risk factors that have come from longer followup and revised dosimetry in major studies on the Japanese A-bomb survivors. This report also provides suggestions about future revisions of computational aspects on health effects models. (author)

  19. Health effects models for off-site radiological consequence analysis on nuclear reactor accidents (II)

    This report is a revision of JAERI-M 91-005, 'Health Effects Models for Off-Site Radiological Consequence Analysis of Nuclear Reactor Accidents'. This revision provides a review of two revisions of NUREG/CR-4214 reports by the U.S. Nuclear Regulatory Commission which is the basis of the JAERI health effects models and other several recent reports that may impact the health effects models by international organizations. The major changes to the first version of the JAERI health effects models and the recommended parameters in this report are for late somatic effects. These changes reflect recent changes in cancer risk factors that have come from longer followup and revised dosimetry in major studies on the Japanese A-bomb survivors. This report also provides suggestions about future revisions of computational aspects on health effects models. (author)

  20. The radiological consequences in the USSR from the Chernobyl accident: Description of the scheme of implementation

    After October 1989 the Government of the USSR requested the IAEA to organize an international assessment of the 'concept which the USSR has evolved to enable the population to live safely in areas affected by radioactive contamination following the Chernobyl accident, and an evaluation of the effectiveness of the steps taken in these areas to safeguard the health of the population'. The IAEA responded positively to this request for special assistance. The IAEA is carried out an extensive international project involving over 100 experts who assessed the human health and environmental consequences in the affected areas of Byelorussia, the Ukraine, and the Russian Federation, and evaluate measures taken by Soviet authorities to protect the population and the environment

  1. The fuzzy set theory application to the analysis of accident progression event trees with phenomenological uncertainty issues

    Fuzzy set theory provides a formal framework for dealing with the imprecision and vagueness inherent in the expert judgement, and therefore it can be used for more effective analysis of accident progression of PRA where experts opinion is a major means for quantifying some event probabilities and uncertainties. In this paper, an example application of the fuzzy set theory is first made to a simple portion of a given accident progression event tree with typical qualitative fuzzy input data, and thereby computational algorithms suitable for application of the fuzzy set theory to the accident progression event tree analysis are identified and illustrated with example applications. Then the procedure used in the simple example is extended to extremely complex accident progression event trees with a number of phenomenological uncertainty issues, i.e., a typical plant damage state 'SEC' of the Zion Nuclear Power Plant risk assessment. The results show that the fuzzy averages of the fuzzy outcomes are very close to the mean values obtained by current methods. The main purpose of this paper is to provide a formal procedure for application of the fuzzy set theory to accident progression event trees with imprecise and qualitative branch probabilities and/or with a number of phenomenological uncertainty issues. (author)

  2. Calculation of dose consequences of a hypothetical large accident at a nuclear power reactor

    The fission product release to the atmosphere from a nuclear reactor during a hypothetical large accident is discussed, and the consequences in terms of doses to the population are calculated. The reactor is a light-water reactor located at a site representing an idealized, simplified Danish location. Three release categories are discussed: The first is the release in an accident with a core meltdown and a major rupture of the containment. This release is represented by the BWR-2 release of WASH-1400. The second is the release where the containment integrity is maintained, but there is a failure to isolate the containment. This release is represented by the PWR-4 release. The third is obtained as a Best Estimate from Empirical Data, and it is called the BEED release. The release of the BEED case is deduced from empirical evidence - especially the SL-1 accident - in a seperate study which is described in the appendix. The release fractions for the most significant elements such as iodine and cesium decrease by a decade from BWR-2 to PWR-4, and from PWR-4 to BEED, while the release fractions of the noble gases are assumed to be at an almost constant high level. The dose consequences in terms of a long-term committed effective dose equivalent is found to be practically directly proportional to the release fractions, i.e. decreasing by a decade from BWR-2 to PWR-4, and from PWR-4 to BEED. For the acute bone marrow dose the contribution from the noble gases is significant in all three cases, and as the noble gas release is almost constant the decrease from one case to the next is of the order of only half a decade. For the BEED case the noble gases, which give an external gamma dose from the plume, are the most significant radioactive fission products, both for long-term and acute doses. For the BWR-2 and PWR-4 cases the I-131 in the plume is predominant in the acute dose, while Cs-137 deposited on the ground is the main contributor to the long-term dose. (author)

  3. Uncertainties in the analysis of water ingress accident for the HTGR cores

    Behaviour of the reactor major physical characteristics during the accident related to the water/steam ingress into the core, resulted from the steam generator (SG) loss of integrity has been analysed on the example of the VGM reactor with the pebble bed core designed in the USSR. The header tube instantaneous double-ended rupture without interaction of the outgoing flows has been considered due to the uncertainties of its failure process. Calculation of water quantity discharged into the core has been made under the following assumptions: 1) Accumulation of water in liquid state in the core is eliminated in as much as the fuel elements and helium temperature exceed water boiling temperature at a pressure of about 5 MPa: 2) Chemical interaction of water with graphite is not taken into account: 3) Moisture sensors fail to be actuated. The calculation results of the water mass variations in the core vs. time as well as reactivity changes caused by water ingress into the core are given in the paper. The need to take into account reactivity changes caused by the front edge of the steam/helium mixture that defines the neutron power increase rate has been shown is the paper. Changes of the reactivity compensation members' efficiency at a steam/water ingress into the core and reflector both in hot and cooled down reactor have been evaluated. The paper carries requirements for experimental investigations intended to prove the adequacy of the reactivity compensation members' efficiency in the accident under consideration. (author). 6 refs, 3 figs

  4. PWR rod ejection accident: uncertainty analysis on a high burn-up core configuration

    Le Pallec, J.C.; Studer, E.; Royer, E. [CEA Saclay, Direction de l' Energie Nucleaire, Service d' Etudes de Reacteurs et de Modelisation Avancee (DEN/SERMA), 91 - Gif sur Yvette (France)

    2003-07-01

    With the increasing of the discharge burn-up assembly, the rod ejection accident (REA) methodology based on the analyse of the hot spot from a decoupling methods of calculation does not allow to ensure the respect of safety criteria. The main reason is that the irradiated fuel certainly less solicited thermally is in the other hand more sensitive to a transient due to a rod ejection. Thus, the hot spot is not necessarily the sensitive point of the core. In the framework of high burn-up configurations, a new methodology tends to replace the former. It characterizes by the use of a best-estimate 3-dimensional modelling: coupling of the thermal hydraulics and neutronics, taking in account fuel properties depending on irradiation. To ensure the conservatism of the modelling response, this new approach has to be followed by an uncertainties analysis. Inputs from the benchmark RIA TMI-1 conducted by IRSN (France), NRC (United State of America) and KI (Russian) are used to perform a first analysis. The response of the modelling is the enthalpy deposited in an assembly. The analysis is based on the Design of Experiments (DoE) that permits to measure the weight of the main parameters and their interactions on the response. These last cannot be disregarded because they represent up to 20% of the penalizing uncertainty. This study shows that the main fuel modifications due to irradiation (radial power distribution, thermal properties degradation) have to be taken into account in a realistic thermal modelling during a strong transient.

  5. Study on the possible consequences of a severe accident in a Swiss nuclear power plant on the drinking water supply

    The study on the possible consequences of a severe accident in a Swiss nuclear power plant on the drinking water supply covers the following issues: estimation of possible source terms and radioactive materials release rates, airborne water contamination, water contamination by direct pollution, consequences for the drinking water supply, emergency measures in case of a drinking water contamination, routine surveillance of surface and ground water and improvement possibilities in nuclear power plants.

  6. Analysis of medico-biological consequences of ChNPP accident for liquidators-participants of the Russian scientific centre

    A base of medico-biological and dosimetric data was created for research workers of Kurchatov Institute, and Institute of nuclear reactors who participated in ChNPP accident mitigation. An attempt is made to analyze possible connection of medico-biological consequences with dose loads

  7. Application of natural adsorbents as decontamination agents for the elimination of the consequences of the Chernobyl reactor accident

    The scientific foundations of using natural adsorbents as ion exchangers,filtering media and adagulants for water purification ase presented. The results showing the efficiency of practical application of natural adsorbents for the decontamination of water, clothes, machinery, construction materials, etc. during the elimination of the consequences of the Chernobyl reactor accident in 1986-1987 are presented

  8. Chernobyl nuclear reactor accident fallout: Measurement and consequences. (Latest citations from the NTIS bibliographic database). Published Search

    The bibliography contains citations concerning the consequences of radioactive fallout from the Chernobyl nuclear reactor accident. Citations discuss radioactive monitoring, health hazards, and radiation dosimetry. Radiation contamination in the air, soil, vegetation, and food is examined. (Contains a minimum of 210 citations and includes a subject term index and title list.)

  9. Chernobyl nuclear reactor accident fallout: Measurement and consequences. (Latest citations from the NTIS Bibliographic database). Published Search

    The bibliography contains citations concerning the consequences of radioactive fallout from the Chernobyl nuclear reactor accident. Citations discuss radioactive monitoring, health hazards, and radiation dosimetry. Radiation contamination in the air, soil, vegetation, and food is examined. (Contains a minimum of 208 citations and includes a subject term index and title list.)

  10. A dynamic food-chain model and program for predicting the consequences of nuclear accident

    1998-01-01

    A dynamic food-chain model and program, DYFOM-95, forpredicting the radiological consequences of nuclear accident hasbeen developed, which is not only suitable to the West food-chainbut also to Chinese food chain. The following processes, caused byaccident release which will make an impact on radionuclideconcentration in the edible parts of vegetable are considered: dryand wet deposition interception and initial retention,translocation, percolation, root uptake and tillage. Activityintake rate of animals, effects of processing and activity intakeof human through ingestion pathway are also considered incalculations. The effects of leaf area index LAI of vegetable areconsidered in dry deposition model. A method for calculating thecontribution of rain with different period and different intensityto total wet deposition is established. The program contains 1 maincode and 5 sub-codes to calculate dry and wet deposition on surfaceof vegetable and soil, translocation of nuclides in vegetable,nuclide concentration in the edible parts of vegetable and inanimal products and activity intake of human and so on.

  11. Internal dose coefficients for off-site radiological consequence analysis of nuclear reactor accidents

    The OSCAAR computer code for use in probabilistic accident consequence assessment (Level 3PSA) developed at Japan Atomic Energy Research Institute has calculated dose to the public with internal dose conversion factors based on dosimetric models and biokinetic data provided in International Commission on Radiological Protection (ICRP) Publication 30. Since ICRP issued age-dependent biokinetic models for a limited set of radioisotopes are ICRP Publication 56, a new Human Respiratory Tract model, age-dependent biokinetic model for other radioisotopes and urinary and faecal excretion models were issued. ICRP has published age-dependent internal dose coefficients for a large set of radionuclides in its publications, but they provided only committed effective dose coefficients for inhalation and ingestion. Since OSCAAR estimated acute and late health effects for members of the public, it needs internal dose coefficients for specific tissues and organs in arbitrary integration times. This report describes a preprocessor code DSYS developed for use with OSCAAR for calculating inhalation and ingestion dose coefficients based on these new ICRP models. It also provides the internal dose coefficients for 54 radionuclides used in OSCAAR calculations. (author)

  12. Consequences of the Chernobyl accident for the natural and human environments

    In the ten years since the Chernobyl accident, an enormous amount of work has been done to assess the consequences to the natural and human environment. Although it is difficult to summarize such a large and varied field, some general conclusions can be drawn. This background paper includes the main findings concerning the direct impacts of radiation on the flora and fauna; the general advances of knowledge in the cycling of radionuclides in natural, seminatural and agricultural environments; some evaluation of countermeasures that were used; and a summary of the human radiation doses resulting from the environmental contamination. although open questions still remain, it can be concluded that: (1) at high radiation levels, the natural environment has shown short term impacts but any significant long term impacts remain to be seen; (2) effective countermeasures can be taken to reduce the transfer of contamination from the environment to humans but these are highly site specific and must be evaluated in terms of practicality as well as population does reduction; (3) the majority of the doses have already been received by the human population. If agricultural countermeasures are appropriately taken, the main source of future doses will be the gathering of food and recreational activities in natural and seminatural ecosystems

  13. Consequences of the Chernobyl accident for the natural and human environments

    Dreicer, M. [Lawrence Livermore National Lab., CA (United States); Aarkog, A. [Risoe National Lab., Roskilde (Denmark); Alexakhin, R. [Russian Inst. of Agricultural Radiology and Agroecology (Russian Federation); Anspaugh, L. [Lawrence Livermore National Lab., CA (United States); Arkhipov, N.P. [Scientific and Technical Centre of the RIA `Pripyat` (Ukraine); Johansson, K.-J. [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden)

    1996-07-01

    In the ten years since the Chernobyl accident, an enormous amount of work has been done to assess the consequences to the natural and human environment. Although it is difficult to summarize such a large and varied field, some general conclusions can be drawn. This background paper includes the main findings concerning the direct impacts of radiation on the flora and fauna; the general advances of knowledge in the cycling of radionuclides in natural, seminatural and agricultural environments; some evaluation of countermeasures that were used; and a summary of the human radiation doses resulting from the environmental contamination. although open questions still remain, it can be concluded that: (1) at high radiation levels, the natural environment has shown short term impacts but any significant long term impacts remain to be seen; (2) effective countermeasures can be taken to reduce the transfer of contamination from the environment to humans but these are highly site specific and must be evaluated in terms of practicality as well as population does reduction; (3) the majority of the doses have already been received by the human population. If agricultural countermeasures are appropriately taken, the main source of future doses will be the gathering of food and recreational activities in natural and seminatural ecosystems.

  14. General situation of the radiological consequences of the Chernobyl accident in Ukraine

    Following the Chernobyl Nuclear Accident on April 26, 1986, epidemiological analyses of data point to impressive deterioration of the health of the people affected by radionuclide contamination in the environment. This deterioration of population health embraces a broad spectrum of diseases. Epidemiological prediction of the rate of thyroid cancer in children near Chernobyl seems strikingly compatible with a real increase. But there is a tendency to consider the morbidity augmentation as a result having been associated with the factors of non-radioactive origin (chemical compounds, heavy metals and mainly social-psychological syndrome development). The Chernobyl catastrophe has implied a heavy burden for Ukraine: pollution of air, water, soils and vegetation in all ecosystems, late radiological effects in the health of people, losses of arable land and forest, necessity of mass-evacuation from thousands of settlements in the contaminated regions, severe psychological shock for millions of people, and painful suffering of unexpected life tragedies. Eleven years after, this tragic event with its causes and consequence brings one to very important conclusions concerning moral aspects of human relations within the nuclear society, as well as interactions between the society and the environment. (J.P.N.)

  15. Uncertainties propagation in the framework of a Rod Ejection Accident modeling based on a multi-physics approach

    The control of uncertainties in the field of reactor physics and their propagation in best-estimate modeling are a major issue in safety analysis. In this framework, the CEA develops a methodology to perform multi-physics simulations including uncertainties analysis. The present paper aims to present and apply this methodology for the analysis of an accidental situation such as REA (Rod Ejection Accident). This accident is characterized by a strong interaction between the different areas of the reactor physics (neutronic, fuel thermal and thermal hydraulic). The modeling is performed with CRONOS2 code. The uncertainties analysis has been conducted with the URANIE platform developed by the CEA: For each identified response from the modeling (output) and considering a set of key parameters with their uncertainties (input), a surrogate model in the form of a neural network has been produced. The set of neural networks is then used to carry out a sensitivity analysis which consists on a global variance analysis with the determination of the Sobol indices for all responses. The sensitivity indices are obtained for the input parameters by an approach based on the use of polynomial chaos. The present exercise helped to develop a methodological flow scheme, to consolidate the use of URANIE tool in the framework of parallel calculations. Finally, the use of polynomial chaos allowed computing high order sensitivity indices and thus highlighting and classifying the influence of identified uncertainties on each response of the analysis (single and interaction effects). (authors)

  16. Best estimate and uncertainty analysis of a critical large break loss of coolant accident at Darlington NGS

    This paper briefly describes the development and application of a Best Estimate Analysis with Uncertainty (BEAU) methodology to a critical large break loss of coolant accident at Darlington NGS. Best estimate and uncertainty predictions are obtained for maximum fuel centreline temperature, maximum fuel sheath temperature, maximum fuel string relative axial expansion, and peak pressure tube strain. The results are compared against similar results obtained using the Limit of Operating Envelope (LOE) approach reported in the most recent licensing submission. The comparison shows significant improvements in predicted safety margins can be achieved. (author)

  17. Radiological consequence analyses under severe accident conditions for the Advanced Neutron Source Reactor at the Oak Ridge National Laboratory

    This paper discusses salient aspects of methodology, assumptions, modeling of various features related to radiation exposure, and health consequences from source terms resulting from two conservatively scoped severe accident scenarios. Radiological consequences for a site-suitability scenario based on 10 CFR 100 guidelines also are presented. Consequences arising from severe accidents involving steaming pools and core-concrete interaction (CCI) events combined with several different containment configurations are presented. Results are presented in the form of mean cumulative values for prompt and latent cancer fatality estimates and related cumulative, complementary distribution functions as a function of distance from the reactor site. It is shown that the reactor-site-suitability risk goals are met by a large margin and that overall risk is dominated by early containment failure combined with CCI events

  18. Review of psychological consequences of nuclear accidents and empirical study on peoples reactions to radiation protection activities in an imagined situation

    The report consist of two parts: a review of studies on psychological consequences of nuclear and radiation accidents in population and an empirical study of peoples reactions to protection actions in an event of hypothetical accident. Review is based on research results from two nuclear reactor accidents (Three Mile Island 1979, Chernobyl 1986) and a radiation accident in Goiania, Brazil 1987. (53 refs, 2 figs.,7 tabs.)

  19. Impact of Uncertainty in SWAT Model Simulations on Consequent Decisions on Optimal Crop Management Practices

    Krishnan, N.; Sudheer, K. P.; Raj, C.; Chaubey, I.

    2015-12-01

    The diminishing quantities of non-renewable forms of energy have caused an increasing interest in the renewable sources of energy, such as biofuel, in the recent years. However, the demand for biofuel has created a concern for allocating grain between the fuel and food industry. Consequently, appropriate regulations that limit grain based ethanol production have been developed and are put to practice, which resulted in cultivating perennial grasses like Switch grass and Miscanthus to meet the additional cellulose demand. A change in cropping and management practice, therefore, is essential to cater the conflicting requirement for food and biofuel, which has a long-term impact on the downstream water quality. Therefore it is essential to implement optimal cropping practices to reduce the pollutant loadings. Simulation models in conjunction with optimization procedures are useful in developing efficient cropping practices in such situations. One such model is the Soil and Water Assessment Tool (SWAT), which can simulate both the water and the nutrient cycle, as well as quantify long-term impacts of changes in management practice in the watershed. It is envisaged that the SWAT model, along with an optimization algorithm, can be used to identify the optimal cropping pattern that achieves the minimum guaranteed grain production with less downstream pollution, while maximizing the biomass production for biofuel generation. However, the SWAT simulations do have a certain level of uncertainty that needs to be accounted for before making decisions. Therefore, the objectives of this study are twofold: (i) to understand how model uncertainties influence decision-making, and (ii) to develop appropriate management scenarios that account the uncertainty. The simulation uncertainty of the SWAT model is assessed using Shuffled Complex Evolutionary Metropolis Algorithm (SCEM). With the data collected from St. Joseph basin, IN, USA, the preliminary results indicate that model

  20. Fukushima Daiichi Unit 1 Accident Progression Uncertainty Analysis and Implications for Decommissioning of Fukushima Reactors - Volume I.

    Gauntt, Randall O. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Mattie, Patrick D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2016-01-01

    Sandia National Laboratories (SNL) has conducted an uncertainty analysis (UA) on the Fukushima Daiichi unit (1F1) accident progression with the MELCOR code. The model used was developed for a previous accident reconstruction investigation jointly sponsored by the US Department of Energy (DOE) and Nuclear Regulatory Commission (NRC). That study focused on reconstructing the accident progressions, as postulated by the limited plant data. This work was focused evaluation of uncertainty in core damage progression behavior and its effect on key figures-of-merit (e.g., hydrogen production, reactor damage state, fraction of intact fuel, vessel lower head failure). The primary intent of this study was to characterize the range of predicted damage states in the 1F1 reactor considering state of knowledge uncertainties associated with MELCOR modeling of core damage progression and to generate information that may be useful in informing the decommissioning activities that will be employed to defuel the damaged reactors at the Fukushima Daiichi Nuclear Power Plant. Additionally, core damage progression variability inherent in MELCOR modeling numerics is investigated.

  1. Fukushima Daiichi Unit 1 Accident Progression Uncertainty Analysis and Implications for Decommissioning of Fukushima Reactors - Volume I

    Sandia National Laboratories (SNL) has conducted an uncertainty analysis (UA) on the Fukushima Daiichi unit (1F1) accident progression with the MELCOR code. The model used was developed for a previous accident reconstruction investigation jointly sponsored by the US Department of Energy (DOE) and Nuclear Regulatory Commission (NRC). That study focused on reconstructing the accident progressions, as postulated by the limited plant data. This work was focused evaluation of uncertainty in core damage progression behavior and its effect on key figures-of-merit (e.g., hydrogen production, reactor damage state, fraction of intact fuel, vessel lower head failure). The primary intent of this study was to characterize the range of predicted damage states in the 1F1 reactor considering state of knowledge uncertainties associated with MELCOR modeling of core damage progression and to generate information that may be useful in informing the decommissioning activities that will be employed to defuel the damaged reactors at the Fukushima Daiichi Nuclear Power Plant. Additionally, core damage progression variability inherent in MELCOR modeling numerics is investigated.

  2. Assessment Of Source Term And Radiological Consequences For Design Basis Accident And Beyond Design Basis Accident Of The Dalat Nuclear Research Reactor

    The paper presents results of the assessment of source terms and radiological consequences for the Design Basis Accident (DBA) and Beyond Design Basis Accident (BDBA) of the Dalat Nuclear Research Reactor. The dropping of one fuel assembly during fuel handling operation leading to the failure of fuel cladding and the release of fission products into the environment was selected as a DBA for the analysis. For the BDBA, the introduction of a step positive reactivity due to the falling of a heavy block from the rotating bridge crane in the reactor hall onto a part of the platform where are disposed the control rod drives is postulated. The result of the radiological consequence analyses shows that doses to members of the public are below annual dose limit for both DBA and BDBA events. However, doses from exposure to operating staff and experimenters working inside the reactor hall are predicted to be very high in case of BDBA and therefore the protective actions should be taken when the accident occurs. (author)

  3. Key drivers and economic consequences of high-end climate scenarios: uncertainties and risks

    Halsnæs, Kirsten; Kaspersen, Per Skougaard; Drews, Martin

    2015-01-01

    The consequences of high-end climate scenarios and the risks of extreme events involve a number of critical assumptions and methodological challenges related to key uncertainties in climate scenarios and modelling, impact analysis, and economics. A methodological framework for integrated analysis...... of extreme events and damage costs is developed and applied to a case study of urban flooding for the medium sized Danish city of Odense. Moving from our current climate to higher atmospheric greenhouse gas (GHG) concentrations including a 2°, 4°, and a high-end 6°C scenario implies that the...... frequency of extreme events increase beyond scaling, and in combination with economic assumptions we find a very wide range of risk estimates for urban precipitation events. A sensitivity analysis addresses 32 combinations of climate scenarios, damage cost curve approaches, and economic assumptions...

  4. A risk measurement tool for an underground electricity distribution system considering the consequences and uncertainties of manhole events

    This paper explores a risk measure of underground vaults that considers the consequences of arc faults. The increasing use of underground systems, together with the aging of networks, the lack of maintenance and interference from other (third party) underground systems nearby have caused many accidents in urban areas, thus endangering human life. The involvement of a large number (hundreds or thousands) of underground vaults with different characteristics, the lack of historical data on modes of failure, the rarity of the occurrence of some faults, the magnitude of their consequences and the involvement of a complex environment surrounding the hazard zone make risk management even more complex and uncertain. Furthermore, given that the (monetary, time, staff, etc.) resources of an electrical power company are limited and scarce, it is necessary to use decision-making tools that aggregate the consequences and the uncertainties to assess the risks jointly with the preference structure of the company, thus solving the problem more realistically. Therefore, this paper puts forward the use of an additional risk analysis for manhole events in underground electrical distribution networks with a view to its being used as a decision aid tool in risk management. As an illustration of the use of the risk measurement tool proposed, a numerical application is presented. The result rather than showing a ranking of underground vaults, gives a measure of the risk used that can show the decision-maker (DM) how much better one group of alternatives (formed by alternatives with quite similar risk values) is than other groups, based on the DM’s attitude to risk and grounded on the axiomatic structure of utility theory. - Highlights: • The paper proposes a risk measure of underground vaults for manhole events. • It makes risk analysis in underground electrical distribution networks. • It makes more than show a risk ranking of underground vaults. • It can show to the DM how

  5. Effect of check valve on consequences of coolant pump rotor seizure accident for EPR reactor

    Counter current flow phenomenon would appear during reactor coolant pump rotor seizure accident. Present work analyzes the coolant pump rotor seizure accident for European Pressurized Reactor (EPR). The accident safety analysis results of model with check valve and with out check valve are compared. It can be found that the check valve can increase the core inlet flow rate of model about 4%. The increasing of coolant flow rate is beneficial to the reactor core cooling. Check valve can increase the minimum departure from nucleate boiling ratio (DNBR), reduce the departure from nucleate boiling (DNB) fraction and the fuel rod cladding temperature about 14℃ during coolant pump rotor seizure accident. The analyses results show that the model with check valve can maintain the integrity of nuclear fuel rod effectively during reactor coolant pump rotor seizure accident. (authors)

  6. COSYMA, a mainframe and PC program package for assessing the consequences of hypothetical accidents

    COSYMA (Code System from MARIA) is a program package for assessing the off-site consequences of accidental releases of radioactive material to atmosphere, developed as part of the European Commission's MARIA programme (Methods for Assessing the Radiological Impact of Accidents). COSYMA represents a fusion of ideas and modules from the Forschungszetrum Karlsruhe program system UFOMOD, the National Radiological Protection Board program MARC and new model developments together with data libraries from other MARIA contractors. Mainframe and PC versions of COSYMA are distributed to interested users by arrangement with the European Commission. The system was first released in 1990, and has subsequently been updated. The program system uses independent modules for the different parts of the analysis, and so permits a flexible problem-oriented application to different sites, source terms, emergency plans and the needs of users in the various parts of Europe. Users of the mainframe system can choose the most appropriate combination of modules for their particular application. The PC version includes a user interface which selects the required modules for the endpoints specified by the user. This paper describes the structure of the mainframe and PC versions of COSYMA, and summarises the models included in them. The mainframe or PC versions of COSYMA have been distributed to more than 100 organisations both inside and outside the European Union, and have been used in a wide variety of applications. These range from full PRA level 3 analyses of nuclear power and research reactors to investigations on advanced containment concepts and the preplanning of off-site emergency actions. Some of the experiences from these applications are described in the paper. An international COSYMA user group has been established to stimulate communication between the owners, developers and users of the code and to serve as a reference point for questions relating to the code. The group produces

  7. An empirical study on causes and consequences of inflation and inflation uncertainty

    Hartmann, Matthias

    2012-01-01

    Empirical study of causality between inflation, inflation uncertainty and other macroeconomicy quantities. Additionally, the issue of how to measure the unobservable inflation uncertainty is addressed.

  8. Diagnostics and medical treatment of multiple somatic pathology for liquidators of consequences of Chernobyl power plant accident

    States conditioned impacts of radiation, chemical and psychologic stresses and appeared by polyorgan combine somatic pathology are typical for liquidators of consequences of Chernobyl power plant accident and of 30-km zone. Minimizing of medicinal therapy, formation of purpose to active recovery, discharge-dietary therapy, organism satiation of vitamins and microelements, creation and progress of dynamic reserves are main principles therapy correction of these states

  9. Scientometric analysis of the means of scientific communication of the problem of medical consequences of Chernobyl Nuclear accident

    In this paper evaluation of the structure and trends in the development of the Ukrainian scientific communication tools on the medical consequences of the Chernobyl nuclear accident using bibliometric methods has been given. The main developers of methodical documents are allocated, the dynamics of the distribution of methodical references, information letters and innovations is estimated. The importance of scientific communications tools in dissemination and use of new medical knowledge is demonstrated

  10. Human exposure to radiation following the release of radioactivity from a reactor accident: a quantitative assessment of the biological consequences

    The objective of this review is to provide a biological basis upon which to assess the consequences of the exposure of a population to radioactivity released after a reactor accident. Depending upon the radiation dose, both early and late somatic damage could occur in the exposed population and hereditary effects may occur in their descendants. The development of dose-effect relationships has been based upon the limited amount of information available on humans, supplemented by data obtained from experiments on animals. (author)

  11. Elimination of the consequences of radiation accidents at the Mayak production association in the 1950s and 1960s

    The paper describes the consequences of radiation accidents happened at Mayak production association located in Chelyabinsk region, Urals, Russia, and countermeasures applied for reduction of radiation exposure of local population. The assessment of the efficiency of countermeasures based on the averted dose criterion is presented. It is stated that the most efficient measures on prevention of the population exposure were relocation of the population and construction of the Techa Reservoir Cascade. (author)

  12. Evaluation of sanitary consequences of Chernobylsk accident in France. Epidemiological surveillance plan, state of knowledge, risks evaluation and perspectives

    This report jointly written by IPSN and InVS, reviews the sanitary consequences in France of the Chernobyl accident, which occurred in 1986. The first point is dedicated to a short presentation of the knowledge relative to the sanitary consequences of the Chernobyl accident in the high contaminated countries and to the risk factors of the thyroid cancer. Secondly, this report describes the main systems of epidemiological surveillance of health implemented in France in 1986 and in 1999, as well as the data of the incidence and mortality of thyroid cancer observed in France since 1975. In addition, this report presents an analysis of the risk of thyroid cancer related to radioactive contamination in France, for young people of less than 15 years of age who where living in 1986 in the highest contaminated areas of France (Eastern territories). For this purpose, the theoretical number of thyroid cancers in excess is evaluated for this population, on the basis of different available risk model. Finally starting from the results of risk assessment, there is a discussion about the relevance and the feasibility of different epidemiological methods in view of answering the questions related to the sanitary consequences of the Chernobyl accident. In conclusion, this report recommends to reinforce the surveillance of thyroid cancer in France. (author)

  13. Effect of the Duration Time of a Nuclear Accident on Radiological Health Consequences

    Hyojoon Jeong

    2014-03-01

    Full Text Available This study aimed to quantify the effect of duration time of a nuclear accident on the radiation dose of a densely populated area and the resulting acute health effects. In the case of nuclear accidents, the total emissions of radioactive materials can be classified into several categories. Therefore, the release information is very important for the assessment of risk to the public. We confirmed that when the duration time of the emissions are prolonged to 7 hours, the concentrations of radioactive substances in the ambient air are reduced by 50% compared to that when the duration time of emission is one hour. This means that the risk evaluation using only the first wind direction of an accident is very conservative, so it has to be used as a screening level for the risk assessment. Furthermore, it is judged that the proper control of the emission time of a nuclear accident can minimize the health effects on residents.

  14. First International Conference of the European Commission, Belarus, Russian Federation and Ukraine on the radiological consequences of the Chernobyl accident

    The First International Conference of European Commission, Belarus, Russian Federation and Ukraine on the radiological consequences of the Chernobyl accident has been held in Minsk, 18-22 March 1996. During the Conference 84 lectures as well as 74 posters have been presented. The most important problems connected with general topic was: the radiation contaminations and their measurements; environmental aspects and between them; radionuclide migration and remedial actions in contaminated areas; healthy consequences with irradiated people curing and epidemiology; thyroid neoplasms in children; organization rescue actions during future radiation disasters

  15. Effect of the Duration Time of a Nuclear Accident on Radiological Health Consequences

    Hyojoon Jeong; Misun Park; Haesun Jeong; Wontae Hwang; Eunhan Kim; Moonhee Han

    2014-01-01

    This study aimed to quantify the effect of duration time of a nuclear accident on the radiation dose of a densely populated area and the resulting acute health effects. In the case of nuclear accidents, the total emissions of radioactive materials can be classified into several categories. Therefore, the release information is very important for the assessment of risk to the public. We confirmed that when the duration time of the emissions are prolonged to 7 hours, the concentrations of radio...

  16. The radiological accident of Goiania and its consequences for the development of law

    The radiological accident of Goiania and its repercussions caused intense debate in Brazilian society, which extended to the legislative sphere. One of the principal outcomes of this debate was the inclusion in the new Brazilian Constitutional Charter of legal provisions covering the control of nuclear energy and of radiation sources. Internationally, the 1986 Vienna Convention on Early Notification of a Nuclear Accident and the Convention on Assistance in the Case of a Nuclear Accident or Radiological Emergency were invoked following the accident and proved to be effective in facilitating international co-operation and solidarity to deal with the aftermath of the accident. A number of international treaties on assistance in the event of nuclear accidents, the management of radioactive waste and the management of spent fuel are currently in force. The Joint Convention on the Safety of Spent Fuel Management and on the Safety of Radioactive Waste, adopted in 1997, is the most recent treaty promoting the sustainability of nuclear activities. Looking ahead, an international legal framework is needed to build upon and improve the principles of a culture of radiation safety. (author)

  17. Uncertainties in hydrological modelling and its consequences for water management in Central Asia

    Malsy, Marcus; aus der Beek, Tim; Flörke, Martina

    2013-04-01

    Central Asia features an extreme continental climate with mostly arid to semi-arid conditions. Due to low precipitation and therefore low water availability, water is a scarce resource and often the limiting factor in terms of socio-economic development. The aim of this model study is to compare the uncertainties of hydrological modelling induced by global and regional climate datasets and to calculate the impacts on estimates of local water resources. Within this integrated model study the hydrological and water use model WaterGAP 3 (Global Assessment and Prognosis) is being applied to all river basins located in Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, Uzbekistan, and Mongolia in five arc minutes spatial resolution (~ 6 x 9 km per grid cell). First of all, water abstractions for the sectors households, irrigation, livestock, manufacturing industries, and electricity production are being computed and fed into the hydrological module of WaterGAP. Then, water fluxes of the terrestrial water cycle are being modelled. The performance of the model is then being evaluated by comparing modelled and observed river discharge for the time period 1971 to 2000. As WaterGAP input, various global and regional climate datasets are available for the study region. In detail, these are the global TS dataset of the Climate Research Unit (CRU), the WATCH forcing data (WFD) developed within the EU-FP6 Project WATer and global CHange (WATCH) and the regional Aphrodités Water Resources dataset. Finally, the uncertainties in modelled water availability induced by the different datasets are quantified to point out the consequences for a sustainable water management. The results show that the datasets differ in both aspects, temporal and spatial goodness. At this, not only differences between the regional and the global datasets, but also among the global datasets are evident.

  18. INFLUENCE OF ANTIHYPERTENSIVE THERAPY ON PSYCHOLOGICAL STATUS OF CHERNOBYL NUCLEAR POWER PLANT ACCIDENT CONSEQUENCES LIQUIDATORS

    E. M. Manoshkina

    2016-01-01

    Full Text Available Aim. To study psychological status and influence of antihypertensive therapy (AHT on it in Chernobyl nuclear power plant (NPP accident consequences liquidators, who suffer arterial hyper-tension (AH, with controlled treatment compared to the standard treatment in out-patient clinic. Material and methods. 81 liquidators with AH (all men were included into open compara-tive randomized study. Study duration was 12 months. Patients were randomized into main group (MG and control group (CG. Patients of MG received strictly regulated stepped AHT based on ACE inhibitor spirapril 6 mg daily (Quadropril®, Pliva-AVD, hypothiazide was added if necessary (12.5-25 mg daily and afterwards – atenolol (12.5-100 mg daily. In CG AHT and its correction was set by physician in polyclinic. Brief multifactor questionnaire for personality analysis was used to study psychological status. Results. 57 patients completed the study, 28 in MG and 29 in CG. In MG target blood pres-sure (BP levels were reached in 22 (78.6% patients, in CG – in 11 (38% patients (p<0.01. The main feature of psychological status of liquidators with AH was hypochondriac, depressive and anxious disorders. Controlled AHT made it possible to reach improvement in psychological status, i.e. growth of optimism and activity of patients, more often, than standard treatment in out-patient clinics. Increase in number of patients with pronounced anxious changes was observed in CG. Effi-ciency of AHT in liquidators with AH is connected with severity of depressive disturbances: in subgroups with inefficient treatment patients had the highest level of depression. In liquidators with AH, possessing neurotic disturbances, spirapril was efficient both as monotherapy, and in combina-tion with diuretic hydrochlorothiazide and beta-blocker atenolol. Conclusion. Controlled AHT in liquidators with AH has advantages over standard treatment in out-patient clinic and results in more frequent target BP level

  19. Perceptions of technology uncertainty and the consequences for performance in buyer-supplier relationships

    Oosterhuis, M.; van der Vaart, T.; Molleman, E.

    2011-01-01

    In this paper, we investigate how buyers' and suppliers' distinct perceptions of technology uncertainty affect the relationship between communication frequency and supplier performance. Information processing theory suggests that a fit is desirable between perceived environmental uncertainty and the

  20. Evaluation of sanitary consequences of Chernobyl accident in France: epidemiological monitoring device, state of knowledge, evaluation of risks and perspectives

    The objectives of this document are firstly, to present the situation of knowledge both on the sanitary consequences of the Chernobyl accident and on the risk factors of thyroid cancers, these ones constituting one of the most principal consequences observed in Belarus, in Ukraine and Russia; secondly, the give the principal system contributing to the epidemiological surveillance of effects coming from a exposure to ionizing radiations, in France and to give the knowledge on incidence and mortality of thyroid cancer in France; thirdly, to discuss the pertinence and the feasibility of epidemiological approaches that could be considered to answer questions that the public and authorities ask relatively to the sanitary consequences of Chernobyl accident in France; fourthly to male a calculation of thyroid cancer risk in relation with Chernobyl fallout in France from works and studies made from 1986 on the consequences of this disaster in terms of radioecology and dosimetry at the national level. Besides, the improvement of thyroid cancer surveillance is also tackled. (N.C.)

  1. Assessing the consequences in a nuclear accident scenario at Cernavoda NPP

    Having in view a possible nuclear incident, considerable planning is necessary to reduce at manageable levels the types of decisions leading to effective responses concerning the public protection. One of the most important parts of an emergency response plan is the computerized system which allows to predict the radiological impact of the accident and to provide information in a manageable and effective form for evaluating alternative countermeasure strategies in the various stages of the accident. In this paper the PC-COSYMA results for early containment failure of a CANDU reactor are presented. The deterministic health effects arising in nuclear accident situation are also presented. As source term we have used the core inventory obtained with ORIGEN computer code. The essential input parameters for PC-COSYMA computer code are also done. (authors)

  2. Local Consequences of Global Uncertainty: Capacity Development and LNG Trade under Shale Gas and Demand Uncertainty and Disruption Risk

    Ruud Egging; Franziska Holz

    2015-01-01

    Recent supply security concerns in Europe have revived interest into the natural gas market. Here, we investigate investment behavior and trade in an imperfect market structure under uncertainty in both supply and demand. We focus on three uncertain events: i) transit of Russian gas via Ukraine that may be disrupted from 2020 on; ii) natural gas intensity of electricity generation in OECD countries that may lead to higher or lower natural gas demand after 2025; and iii) availability of shale ...

  3. Local consequences of global uncertainty: Capacity development and LNG trade under shale gas and demand uncertainty and disruption risk

    Egging, Ruud; Holz, Franziska

    2015-01-01

    Recent supply security concerns in Europe have revived interest into the natural gas market. Here, we investigate investment behavior and trade in an imperfect market structure under uncertainty in both supply and demand. We focus on three uncertain events: i) transit of Russian gas via Ukraine that may be disrupted from 2020 on; ii) natural gas intensity of electricity generation in OECD countries that may lead to higher or lower natural gas demand after 2025; and iii) availability of shale ...

  4. The consequences of the Chernobyl accident in the Ukraine and problems with the sarcophagus

    The reactor accident in the Ukraine contaminated part of the territory with iodine 131, caesium 137, strontium 90, and plutonium 239 and 240. The zone surrounding the site of the accident was declared restricted area; more than 90 000 persons were evacuated. The paper reports on current conditions in the restricted area and prospects for this area as well as on the current state of, and problems with, the sarcophagus. The conversion of the sarcophagus into an ecologically safe system and the economic situation of the Ukraine pose great problems. (DG)

  5. Uncertainty of climate change impacts and consequences on the prediction of future hydrological trends

    In the future, water is very likely to be the resource that will be most severely affected by climate change. It has been shown that small perturbations in precipitation frequency and/or quantity can result in significant impacts on the mean annual discharge. Moreover, modest changes in natural inflows result in larger changes in reservoir storage. There is however great uncertainty linked to changes in both the magnitude and direction of future hydrological trends. This presentation discusses the various sources of this uncertainty and their potential impact on the prediction of future hydrological trends. A companion paper will look at adaptation potential, taking into account some of the sources of uncertainty discussed in this presentation. Uncertainty is separated into two main components: climatic uncertainty and 'model and methods' uncertainty. Climatic uncertainty is linked to uncertainty in future greenhouse gas emission scenarios (GHGES) and to general circulation models (GCMs), whose representation of topography and climate processes is imperfect, in large part due to computational limitations. The uncertainty linked to natural variability (which may or may not increase) is also part of the climatic uncertainty. 'Model and methods' uncertainty regroups the uncertainty linked to the different approaches and models needed to transform climate data so that they can be used by hydrological models (such as downscaling methods) and the uncertainty of the models themselves and of their use in a changed climate. The impacts of the various sources of uncertainty on the hydrology of a watershed are demonstrated on the Peribonka River basin (Quebec, Canada). The results indicate that all sources of uncertainty can be important and outline the importance of taking these sources into account for any impact and adaptation studies. Recommendations are outlined for such studies. (author)

  6. Uncertainties under emergency conditions in Hiroshima and Nagasaki in 1945 and Bikini accident in 1954

    In exploding an atomic bomb, in addition to ionizing radiation, strong non-ionizing radiation, such as infrared, ultraviolet light, visible light, electromagnetic pulse radiation, as well as heat and shock waves are produced. The survivors and those who visited Hiroshima immediately after the atomic bombing could have been subjected to a number of other possible noxious effects in addition to atomic radiation. Hospitals, laboratories, drugstores, pharmaceutical works, storehouses of chemicals, factories, etc. that were situated close to the hypocenter were all completely destroyed and various mutagenic, carcinogenic or teratogenic substances must have been released, many doctors, nurses and chemists were killed. There was no medical care and no food in the region of high dose exposure and the drinking water was contaminated. There would have been various possibilities of infection. Mental stress would also have been much higher in the survivors closer to the hypocenter. It is confusing which factor played a dominant role. In addition, there would be problems in accurately identifying the position of the exposed persons at the time of the atomic bombing and also in estimating the shielding factors. There may be considerable uncertainty in human memory under such conditions. It is also possible that there could have been a large storage of gasoline to be used for transportation of the army corps in Hiroshima. Therefore there is a possibility that various toxic substances, mutagenic or carcinogenic agents such as benzopyrene and other radiomimetic substances, chemical weapons (Yperit, Lewisite, etc.) could have been released from various facilities which were destroyed at the time of the atomic bombing. After the German surrender, in May 1945, it was reported in June, in Japan, that the USA might attempt landing on Japan mainland, and that they might be planning massive use of chemical weapons all over Japan on that occasion. Preparing for such case chemical officers

  7. Uncertainties under emergency conditions in Hiroshima and Nagasaki in 1945 and Bikini accident in 1954

    Nishiwaki, Y. [Universitaet Wien, Institut fuer Medizinische Physik, Vienna (Austria); Kawai, H. [Atomic Energy Research Institute of Kinki Univ., Osaka (Japan); Shono, N. [Hiroshima Jogakuin Univ., Hiroshima (Japan); Fujita, S. [Radiation Effects Research Foundation, Department of Statistics, Hiroshima (Japan); Matsuoka, H. [Japan Atomic Energy Research Institute, Earth Simulator Research and Development Center, Tokyo (Japan); Fujiwara, S. [Japan Nuclear Cycle Development Institute, Ibaraki (Japan); Hosoda, T. [Chiyoda Technol Corporation, Tokyo (Japan)

    2000-05-01

    In exploding an atomic bomb, in addition to ionizing radiation, strong non-ionizing radiation, such as infrared, ultraviolet light, visible light, electromagnetic pulse radiation, as well as heat and shock waves are produced. The survivors and those who visited Hiroshima immediately after the atomic bombing could have been subjected to a number of other possible noxious effects in addition to atomic radiation. Hospitals, laboratories, drugstores, pharmaceutical works, storehouses of chemicals, factories, etc. that were situated close to the hypocenter were all completely destroyed and various mutagenic, carcinogenic or teratogenic substances must have been released, many doctors, nurses and chemists were killed. There was no medical care and no food in the region of high dose exposure and the drinking water was contaminated. There would have been various possibilities of infection. Mental stress would also have been much higher in the survivors closer to the hypocenter. It is confusing which factor played a dominant role. In addition, there would be problems in accurately identifying the position of the exposed persons at the time of the atomic bombing and also in estimating the shielding factors. There may be considerable uncertainty in human memory under such conditions. It is also possible that there could have been a large storage of gasoline to be used for transportation of the army corps in Hiroshima. Therefore there is a possibility that various toxic substances, mutagenic or carcinogenic agents such as benzopyrene and other radiomimetic substances, chemical weapons (Yperit, Lewisite, etc.) could have been released from various facilities which were destroyed at the time of the atomic bombing. After the German surrender, in May 1945, it was reported in June, in Japan, that the USA might attempt landing on Japan mainland, and that they might be planning massive use of chemical weapons all over Japan on that occasion. Preparing for such case chemical officers

  8. Consequences of Windscale accident (October 1957) and study of the validity of the Sutton's mathematical model of atmospheric diffusion (1960)

    The reactor accident that happens at the number 1 pile of Windscale in 1957 was followed by a discharge of radioactive products into the atmosphere from the 1.X.1957 at 4.30 PM to the 12.X.1957 at 3.10 PM. On october the 11th it was possible to say that there was no more risk either of external irradiation or inhalation. But in adopting a M.A.C. of 0,1 μcurie of iodine 131 per litre of milk, the Authority had to control the milk delivery till november 23rd on a 500 km2 area. On the other hand, this exceptional accident permit to verify that Sutton's atmospheric diffusion model could give an easy means to foresee, with a sufficient approximation, the consequences of a dispersion of radioactive products into the atmosphere. (author)

  9. Comparison of the foodchain transport models of WASH-1400 and MARC using the accident consequence model UFOMOD

    Within the frame of the contract with the European Community 'Methods for Assessing the Radiological Impact of Accidents' (CEC-MARIA) comparative accident consequence assessments were performed with the computer code UFOMOD, replacing the currently implemented foodchain transport model of the WASH-1400 study by the dynamic transport model of the MARC methodology. The calculations were based on the release category FK2 of the German Risk Study with meteorological data representing four different regions of the Federal Republic of Germany. The study of seasonal variations was carried out with the MARC data for four representative times of deposition with an agricultural practice adopted in the UK. In this report the differences are presented which are observed in the potential doses due to ingestion, the areas affected by food-bans and the late health effects when using both models and taking the influence of seasonal effects into account. (orig.)

  10. Consequences of major nuclear accidents on wild fauna and flora: dosimetric assessments remain a weakness to establish robust conclusions

    As about hundred of studies have been undertaken after the major nuclear accidents (Chernobyl and Fukushima) to study the consequences of these accidents on wild flora and fauna, notably on the effects of low doses of ionizing radiations, it appears that some of them reported noticeable effects due to extremely low doses. Such findings put knowledge in radiobiology into question again. This note aims at discussing the importance of the quality of dosimetric assessments for any study performed 'in natura'. It seems that the ambient external dose rate is not systematically a good indicator of the dose or dose rate absorbed by a living organism in radio-contaminated environment. This note outlines the problem related to the spatial heterogeneity of the radioactive contamination, that some statistic methods are not always adapted to data set quality. It briefly indicates other factors which may affect the quality of data set obtained during in situ studies

  11. 10 years after the Chernobyl reactor accident. Thyroid cancer and consequences of public health in the CIS

    Ten years after the accident at the Chernobyl nuclear reactor, governmental and international organisations have identified considerable effects on the health of the various affected groups. A dramatic - over 100-fold - increase in thyroid cancers among children in Belarus has been caused by papillary thyroid carcinomas that are marked by aggressive growth with early metastatic spread. As early as 1995, the number of new cases of thyroid cancer among adults was four times the mean figure in the period before 1986. In Oblast Gomel, the number of children with diabetes mellitus doubled between 1986 and the end of 1995. The number of recorded cases of thyroid cancer, particularly among children, by far exceeds the prognoses made on the basis of established radiation risk estimates, and points to a considerable underestimation of the consequences of the Chernobyl accident. (orig.)

  12. Emergency Responses and Health Consequences after the Fukushima Accident; Evacuation and Relocation.

    Hasegawa, A; Ohira, T; Maeda, M; Yasumura, S; Tanigawa, K

    2016-04-01

    The Fukushima accident was a compounding disaster following the strong earthquake and huge tsunami. The direct health effects of radiation were relatively well controlled considering the severity of the accident, not only among emergency workers but also residents. Other serious health issues include deaths during evacuation, collapse of the radiation emergency medical system, increased mortality among displaced elderly people and public healthcare issues in Fukushima residents. The Fukushima mental health and lifestyle survey disclosed that the Fukushima accident caused severe psychological distress in the residents from evacuation zones. In addition to psychiatric and mental health problems, there are lifestyle-related problems such as an increase proportion of those overweight, an increased prevalence of hypertension, diabetes mellitus and dyslipidaemia and changes in health-related behaviours among evacuees; all of which may lead to an increased cardiovascular disease risk in the future. The effects of a major nuclear accident on societies are diverse and enduring. The countermeasures should include disaster management, long-term general public health services, mental and psychological care, behavioural and societal support, in addition to efforts to mitigate the health effects attributable to radiation. PMID:26876459

  13. Epidemiological survey of the medical consequences of the Chernobyl accident in Ukraine

    The characteristics of the contamination resulting from the Chernobyl accident are defined, as a basis for epidemiological investigations. Due to loss of integrity of the nuclear fuel and thermal buoyancy from fire and nuclear heating, a large quantity of radioisotopes were released over a period of up to 16 days. The areas affected were very large, 37 million hectares in Ukraine alone. About 5 million persons were affected in one way or another, over 2 million of them in Ukraine. Registration and epidemiological follow-up in the former USSR and the three republics afterwards are presented with an emphasis on Ukraine. Considering the long incubation times for some of the expected illnesses and relatively low average doses, the difficulties of confirming significant effects become evident. For example leucosis morbidity among cleanup personnel within a 30 km zone around the accident was 3.4 per 100,000 before the accident and 7 per 100,000 afterwards. The question of the statistical significance of such numbers is discussed by the authors, in the context of confounding factors. For some of the observed effects it has already been established that stress and anxiety caused by the accident and living conditions in the affected areas are the principal cause rather than radiation. According to the authors, more detailed retrospective and prospective epidemiological studies are needed in the future, in order to clarify the causes of observed health effects

  14. Status of safety technology for radiological consequence assessment of postulated accidents in liquid metal fast breeder reactors, Canoga Park, California, 29 July--31 July 1975

    State-of-the-art capabilities are examined for prediction and mitigation of radiological consequences of postulated LMFBR accidents. The following topics are treated: radioactive source terms, sodium reactions, aerosol behavior, radiological dose assessment, and engineered safeguards. (U.S.)

  15. The unique field experiments on the assessment of accident consequences at industrial enterprises of gas-chemical complexes

    Sour natural gas fields are the unique raw material base for setting up such large enterprises as gas chemical complexes. The presence of high toxic H2S in natural gas results in widening a range of dangerous and harmful factors for biosphere. Emission of such gases into atmosphere during accidents at gas wells and gas pipelines is of especial danger for environment and first of all for people. Development of mathematical forecast models for assessment of accidents progression and consequences is one of the main elements of works on safety analysis and risk assessment. The critical step in development of such models is their validation using the experimental material. Full-scale experiments have been conducted by the All-Union Scientific-Research institute of Natural Gases and Gas Technology (VNIIGAZ) for grounding of sizes of hazard zones in case of the severe accidents with the gas pipelines. The source of emergency gas release was the working gas pipelines with 100 mm dia. And 110 km length. This pipeline was used for transportation of natural gas with significant amount of hydrogen sulphide. During these experiments significant quantities of the gas including H2S were released into the atmosphere and then concentrations of gas and H2S were measured in the accident region. The results of these experiments are used for validation of atmospheric dispersion models including the new Lagrangian trace stochastic model that takes into account a wide range of meteorological factors. This model was developed as a part of computer system for decision-making support in case of accident release of toxic gases into atmosphere at the enterprises of Russian gas industry. (authors)

  16. Uncertainty analysis for containment response of U.S. EPR TM reactor to large break loss-of-coolant accidents

    This paper presents an uncertainty analysis applying the GOTHIC containment analysis code to simulate the first 24-hours following a large-break loss-of-coolant accident (LBLOCA) in AREVA's U.S. EPR TM plant. The uncertainty method is modeled after a study performed by the Gesellschaft fur Anlagen und Reaktorsicherheit (GRS) using data from the Heifidampf-Reaktor (HDR) Test T31.5. The analysis method incorporates an assessment of phenomenological importance, identifying the dominant contributors that influence the principle analysis metric, containment pressure. As with the GRS approach, this study employs non-parametric statistics. This analysis illustrates U.S. EPR containment response sensitivity to realistic variation in a set of important model parameters influencing containment conditions during LBLOCA. In considering a set of model uncertainty parameters, a number of GOTHIC variation calculations were performed (59 calculations) to effect a best estimate plus uncertainty result at 95/95 coverage/confidence level for the key metric, containment pressure. The results of the importance analysis showed condensation phenomena on the surface of the containment structures to be important during the passive cooling period, which occurred prior to the start of HL (hot leg) injection of SI (safety injection). In this study, hot leg injection was assumed to initiate at 1.5 hours. Condensation phenomena faded in importance after 1.5 hours due to the hot leg injection of SI suppressing steaming. Structure conduction, especially, the physical properties of concrete, retained importance throughout the transient. (authors)

  17. Uncertainty and Sensitivity of Neutron Kinetic Parameters in the Dynamic Response of a PWR Rod Ejection Accident Coupled Simulation

    C. Mesado

    2012-01-01

    Full Text Available In nuclear safety analysis, it is very important to be able to simulate the different transients that can occur in a nuclear power plant with a very high accuracy. Although the best estimate codes can simulate the transients and provide realistic system responses, the use of nonexact models, together with assumptions and estimations, is a source of uncertainties which must be properly evaluated. This paper describes a Rod Ejection Accident (REA simulated using the coupled code RELAP5/PARCSv2.7 with a perturbation on the cross-sectional sets in order to determine the uncertainties in the macroscopic neutronic information. The procedure to perform the uncertainty and sensitivity (U&S analysis is a sampling-based method which is easy to implement and allows different procedures for the sensitivity analyses despite its high computational time. DAKOTA-Jaguar software package is the selected toolkit for the U&S analysis presented in this paper. The size of the sampling is determined by applying the Wilks’ formula for double tolerance limits with a 95% of uncertainty and with 95% of statistical confidence for the output variables. Each sample has a corresponding set of perturbations that will modify the cross-sectional sets used by PARCS. Finally, the intervals of tolerance of the output variables will be obtained by the use of nonparametric statistical methods.

  18. Radiological consequence analyses of loss of coolant accidents of various break sizes of Pressurized Heavy Water Reactor

    For any advanced technology, it is essential to ensure that the consequences associated with the accident sequences arising, if any, from the operation of the plant are as low as possible and certainly below the guidelines/limits set by the regulatory bodies. Nuclear power is no exception to this. In this paper consequences of the events arising from Loss of Coolant Accident (LOCA) sequences in Pressurized Heavy Water Reactor (PHWR), are analysed. The sequences correspond to different break sizes of LOCA followed by the operation or otherwise of Emergency Core Cooling System (ECCS). Operation or otherwise of the containment safety systems has also been considered. It has been found that there are no releases to the environment when ECCS is available. The releases, when ECCS is not available, arise from the slack and the ground. The radionuclides considered include noble gases, iodine, and cesium. The hourly meteorological parameters (wind speed, wind direction, precipitation and stability category), considered for this study, correspond to those of Kakrapar site. The consequences evaluated are the thyroid dose and the bone marrow dose received by a person located at various distances from the release point. Isodose curves are generated. From these evaluations, it has been found that the doses are very low. The complementary cumulative frequency distributions (CCFD) for thyroid and bone marrow doses have also been presented for the cases analysed. (author)

  19. Source term uncertainties for the Seabrook station probabilistic risk assessment

    Accident source terms are defined as a set of release categories that define the time and quantity of radionuclides released for different containment failure modes and groups of accident sequences. Best estimates of these source terms are characterized by very large uncertainties. A probabilistic risk assessment (PRA) aims to determine realistic consequences. Estimating source term uncertainties is therefore as important as estimating the source terms themselves. A systematic analysis of source term uncertainties was performed for the Seabrook PRA. Uncertainties were quantified due to in-vessel retention, ex-vessel retention, different accident sequences, accident progression phenomena, containment failure time, containment failure modes, and leak path attenuation

  20. Perceptions of Technology Uncertainty and the Consequences for Performance in Buyer-Supplier Relationships

    Oosterhuis, Marian; Vaart, Taco van der; Molleman, Eric

    2011-01-01

    Abstract In this paper, we investigate how buyers? and suppliers? distinct perceptions of technology uncertainty affect the relationship between communication frequency and supplier performance. Information processing theory suggests that a fit is desirable between perceived environmental uncertainty and the communication processes between organisations. However, if partners in a buyer-supplier relationship do not concur on there being a high level of technology uncertainty, it is ...

  1. A two-stage optimization model for emergency material reserve layout planning under uncertainty in response to environmental accidents.

    Liu, Jie; Guo, Liang; Jiang, Jiping; Jiang, Dexun; Liu, Rentao; Wang, Peng

    2016-06-01

    In the emergency management relevant to pollution accidents, efficiency emergency rescues can be deeply influenced by a reasonable assignment of the available emergency materials to the related risk sources. In this study, a two-stage optimization framework is developed for emergency material reserve layout planning under uncertainty to identify material warehouse locations and emergency material reserve schemes in pre-accident phase coping with potential environmental accidents. This framework is based on an integration of Hierarchical clustering analysis - improved center of gravity (HCA-ICG) model and material warehouse location - emergency material allocation (MWL-EMA) model. First, decision alternatives are generated using HCA-ICG to identify newly-built emergency material warehouses for risk sources which cannot be satisfied by existing ones with a time-effective manner. Second, emergency material reserve planning is obtained using MWL-EMA to make emergency materials be prepared in advance with a cost-effective manner. The optimization framework is then applied to emergency management system planning in Jiangsu province, China. The results demonstrate that the developed framework not only could facilitate material warehouse selection but also effectively provide emergency material for emergency operations in a quick response. PMID:26897572

  2. A risk-based evaluation of the impact of key uncertainties on the prediction of severe accident source terms - STU

    The purpose of this project is to address the key uncertainties associated with a number of fission product release and transport phenomena in a wider context and to assess their relevance to key severe accident sequences. This project is a wide-based analysis involving eight reactor designs that are representative of the reactors currently operating in the European Union (EU). In total, 20 accident sequences covering a wide range of conditions have been chosen to provide the basis for sensitivity studies. The appraisal is achieved through a systematic risk-based framework developed within this project. Specifically, this is a quantitative interpretation of the sensitivity calculations on the basis of 'significance indicators', applied above defined threshold values. These threshold values represent a good surrogate for 'large release', which is defined in a number of EU countries. In addition, the results are placed in the context of in-containment source term limits, for advanced light water reactor designs, as defined by international guidelines. Overall, despite the phenomenological uncertainties, the predicted source terms (both into the containment, and subsequently, into the environment) do not display a high degree of sensitivity to the individual fission product issues addressed in this project. This is due, mainly, to the substantial capacity for the attenuation of airborne fission products by the designed safety provisions and the natural fission product retention mechanisms within the containment

  3. Bounding Radionuclide Inventory and Accident Consequence Calculation for the 1L Target

    Kelsey, Charles T. IV [Los Alamos National Laboratory

    2011-01-01

    A bounding radionuclide inventory for the tungsten of the Los Alamos Neutron Science Center (LANSCE) IL Target is calculated. Based on the bounding inventory, the dose resulting from the maximum credible incident (MCI) is calculated for the maximally exposed offsite individual (MEOl). The design basis accident involves tungsten target oxidation following a loss of cooling accident. Also calculated for the bounding radionuclide inventory is the ratio to the LANSCE inventory threshold for purposes of inventory control as described in the target inventory control policy. A bounding radionuclide inventory calculation for the lL Target was completed using the MCNPX and CINDER'90 codes. Continuous beam delivery at 200 {micro}A to 2500 mA{center_dot}h was assumed. The total calculated activity following this irradiation period is 205,000 Ci. The dose to the MEOI from the MCI is 213 mrem for the bounding inventory. The LANSCE inventory control threshold ratio is 132.

  4. Assessment of possible consequences of hypothetical reactivity initiated accident connected with Topaz-2 space NPS landing

    The preliminary results of analysis of the hypothetical accident connected with supercritical state initiation in the case of landing of the Topaz-2 space NPP with the thermionic reactor-converter into water are discussed. The results of analysis of the reactivity effects, when the reactor core cavities are filled with water, are considered. The results of numerical simulation of emergency transients are given as well. It is shown that the reactor has the property to compensate the redundant reactivity due to change of the density (phase state) of water filling the core cavities. At that several damping self-quenching power bursts, which transform into stable oscillations around the mean value amounting to several tens kw, may be initiated at the accident initial stage. 8 refs., 2 tabs., 2 figs

  5. What are the consequences of the reactor accident in Fukushima for the evaluation of nuclear risk?

    There are historical breaks in the relation of risk analysis, risk perception and regulation policy. The year 2011 with the reactor accident in the NPP Fukushima was such a break, especially in Germany. The nuclear phase-out was reduced to ten years the energy policy turnaround received a broad societal agreement. Nuclear facilities loose public acceptance, the risk perception has changed. The Japanese evaluation results on faulty and nontransparent behavior and the lack of governance of responsible persons and authorities including a poor accident management have further decreased the public confidence. A new concept of safety culture for all nuclear facilities including the radioactive waste management is required, the communication processes between plant operator, authorities, science and the public have to be intensified.

  6. Character of protective clothes contamination of the personnel participated in the efforts to eliminate the Chernobyl accident consequences

    The results of investigation of radioactive contamination of protective clothes made of cotton and mixed materials for personnel participated in elimination of the Chernobyl accident consequences are described. Radionuclide composition of clothes contamination before and after decontamination, as well as the values of decontamination coefficients, which are much lower than calculated ones, are presented. Clothes contamination is shown to be caused by difficulty soluble particles of irradiated uranium fuel. The contamination radionuclide composition changes a little as a result of decontamination: decrease only the total quantity of radionuclide substances, but contribution of every radionuclide remains unchanced. During decontamination particles of irradiated uranium fuel are removed from material without solution in the decontaminating solution

  7. Accident simulation and consequence analysis in support of MHTGR safety evaluations

    This paper summarizes research performed at Oak Ridge National Laboratory (ORNL) to assist the Nuclear Regulatory Commission (NRC) in preliminary determinations of licensability of the US Department of Energy (DOE) reference design of a standard modular high-temperature gas-cooled reactor (MHTGR). The work described includes independent analyses of core heatup and steam ingress accidents and the reviews and analyses of fuel performance and fission product transport technology

  8. Accident simulation and consequence analysis in support of MHTGR safety evaluations

    This paper summarizes research performed at Oak Ridge National Laboratory (ORNL) to assist the Nuclear Regulatory Commission (NRC) in preliminary determinations of licensability of the US Department of Energy (DOE) reference design of a standard modular high-temperature gas-cooled reactor (MHTGR). The work described includes independent analyses of core heatup and steam ingress accidents, and the reviews and analyses of fuel performance and fission product transport technology

  9. Accident consequences analysis of the HYLIFE-II inertial fusion energy power plant design

    Reyes, S; Gomez del Rio, J; Sanz, J

    2000-02-23

    Previous studies of the safety and environmental (S and E) aspects of the HYLIFE-II inertial fusion energy (IFE) power plant design have used simplistic assumptions in order to estimate radioactivity releases under accident conditions. Conservatisms associated with these traditional analyses can mask the actual behavior of the plant and have revealed the need for more accurate modeling and analysis of accident conditions and radioactivity mobilization mechanisms. In the present work a set of computer codes traditionally used for magnetic fusion safety analyses (CHEMCON, MELCOR) has been applied for simulating accident conditions in a simple model of the HYLIFE-II IFE design. Here the authors consider a severe lost of coolant accident (LOCA) producing simultaneous failures of the beam tubes (providing a pathway for radioactivity release from the vacuum vessel towards the containment) and of the two barriers surrounding the chamber (inner shielding and containment building it self). Even though containment failure would be a very unlikely event it would be needed in order to produce significant off-site doses. CHEMCON code allows calculation of long-term temperature transients in fusion reactor first wall, blanket, and shield structures resulting from decay heating. MELCOR is used to simulate a wide range of physical phenomena including thermal-hydraulics, heat transfer, aerosol physics and fusion product release and transport. The results of these calculations show that the estimated off-site dose is less than 6 mSv (0.6 rem), which is well below the value of 10 mSv (1 rem) given by the DOE Fusion Safety Standards for protection of the public from exposure to radiation during off-normal conditions.

  10. Consequences of the Chernobyl accident for people and the environment; Les consequences de Tchernobyl pour l'homme et l'environnement

    NONE

    2006-07-01

    This report recalls the accident scenario, discusses the dispersion of the radioactive plume, comments the contamination at the vicinity of the power station, discusses and comments data related to radioactive deposits in Europe and in France, comments available information regarding radioactive fallouts in Belarus, Ukraine and Russia (models have been used to assess radioactive deposits). It addresses the issue of food product contamination in these three countries (impact on farm products, on water streams and on forests), but also in France. It comments the health impacts, more particularly on the people who intervened on the site, but also on people who received medium doses. Thyroid cancer data are discussed for the three mainly concerned countries. Other pathologies and non-cancerous effects are also discussed. The mortality induced by the accident is commented. Effects in France are evoked as well as social and economic consequences in Ukraine, Belarus and Russia. The document provides several links to other documents for further and more detailed information

  11. Important severe accident research issues after Fukushima accident

    After the Fukushima accident several investigation committees issued reports with lessons learned from the accident in Japan. Among those lessons, several recommendations have been made on severe accident research. Similar to the EURSAFE efforts under EU Program, review of specific severe accident research items was started before Fukushima accident in working group of Atomic Energy Society of Japan (AESJ) in terms of significance of consequences, uncertainties of phenomena and maturity of assessment methodology. Re-investigation has been started since the Fukushima accident. Additional effects of Fukushima accident, such as core degradation behaviors, sea water injection, containment failure/leakage and re-criticality have been covered. The review results are categorized in ten major fields; core degradation behavior, core melt coolability/retention in containment vessel, function of containment vessel, source term, hydrogen behavior, fuel-coolant interaction, molten core concrete interaction, direct containment heating, recriticality and instrumentation in severe accident conditions. Based on these activities and also author's personal view, the present paper describes the perspective of important severe accident research issues after Fukushima accident. Those are specifically investigation of damaged core and components, advanced severe accident analysis capabilities and associated experimental investigations, development of reliable passive cooling system for core/containment, analysis of hydrogen behavior and investigation of hydrogen measures, enhancement of removal function of radioactive materials of containment venting, advanced instrumentation for the diagnosis of severe accident and assessment of advanced containment design which excludes long-term evacuation in any severe accident situations. (author)

  12. An Investigation of Spray Performance to Remove Gaseous Iodine- Approach to mitigate the consequences of severe accident

    New technological approaches need to be in place to address such concern which has significantly deteriorated public confidence in nuclear power. Such technological approach must be capable of systematically mitigate the consequence of severe nuclear accidents involving radioactivity release. An example of such approach is spray technology. In case of an accident involving radioactivity release to the environment, it may possible to deploy spray system to quickly respond to the released radioactivity and to minimize the impact of accidental releases on humans and the environment. During early phase of Fukushima nuclear accident mitigation process, water spray operations were carried out through fire trucks and military helicopters, but the primary concern of such operations was to cool down the reactor and to extinguish the fire and not to minimize the spread of radioactive materials. The aim of this research is to investigate spray technology for effective and efficient capturing of fission products released from leaked/damaged nuclear reactor to the environment. For this purpose, a systematic approach with in depth information about release phenomena and spray features will be required. Based on the information regarding release phenomena including types of materials and their amount and size, release locations, release conditions such as rates, velocities, temperature, etc., requirements for spray application is being developed including spray material types (foam, mist etc.), spray solution additives, flow rates, pressure, drop size, spray coverage area and spray duration, etc. Subsequently the efficiency and effectiveness of spray system to reduce the Dispersion of radioactivity in the environment during the course of severe accident can be characterized. This paper is a summary of our initial investigation for the use of spray technology to reduce the consequence of severe nuclear accident. An experimental investigation of iodine removal efficiency in a spray

  13. Uncertainty in the description of water-conducting features and consequences for the calculation of radionuclide transport

    A number of approaches are presented to dealing with uncertainty in the description of water-conducting features which make up pathways for radionuclide transport from a repository for nuclear waste to the biosphere. Using radionuclide transport models, the consequences of these uncertainties can be explored in terms of their influence on calculated releases, yielding information on parameter sensitivity. This in turn allows to focus on the most important parameters in site characterisation work. Three cases from recent Swiss safety assessments are used as examples. (author)

  14. Joint USNRC/EC consequence uncertainty study: The ingestion pathway, dosimetry and health effects expert judgment elicitations and results

    Harper, F. [Sandia National Labs., Albuquerque, NM (United States); Goossens, L. [Delft Univ. of Technology (Netherlands); Abbott, M. [Lockheed Idaho Technologies Co., Idaho Falls, ID (United States)] [and others

    1996-08-01

    The US Nuclear Regulatory Commission (USNRC) and the European Commission (EC) have conducted a formal expert judgment elicitation jointly to systematically collect the quantitative information needed to perform consequence uncertainty analyses on a broad set of commercial nuclear power plants. Information from three sets of joint US/European expert panels was collected and processed. Information from the three sets of panels was collected in the following areas: in the phenomenological areas of atmospheric dispersion and deposition, in the areas of ingestion pathways and external dosimetry, and in the areas of health effects and internal dosimetry. This exercise has demonstrated that the uncertainty for particular issues as measured by the ratio of the 95th percentile to the 5th percentile can be extremely large (orders of magnitude), or rather small (factor of two). This information has already been used by many of the experts that were involved in this process in areas other than the consequence uncertainty field. The benefit to the field of radiological consequences is just beginning as the results of this study are published and made available to the consequence community.

  15. Luminescence techniques for dose reconstruction in accident situations: possibilites, limitations and uncertainties

    In a nuclear accident of even moderate size, locations will inevitably be exposed which do not have adequate monitoring. In these situations nontraditional dosimeters such as brick, tiles or other environmental materials have historically provided measurements against which models of transport and exposure could be tested. Given sufficient speed and accuracy, the utility of TL techniques applied to natural materials can extend well beyond model verification to a variety of dosimetric applications

  16. The radioecological consequences of the Kyshtym and Chernobyl radiation accidents for forest ecosystems

    Following the Urals and Chernobyl accidents 60 to 90% of the radioactive fallout was retained by the above-ground part of forest stands. In the Urals the period for semi-removal of contamination from crowns ranged from 6 to 8 months, compared to around one month in the Chernobyl region - due to different seasonal conditions during the fallout period. The bulk of the dose burden in woody plants' critical organs built up over one to six months. The minimum lethal dose for pine tree needles in the Urals was around 50 Gy, and 25 Gy for the apical meristem; the corresponding figures for Chernobyl were 100 Gy and 25-30 Gy. At lower doses we observed morphological disturbances, reduced growth and suppressed reproductive capability in pines. The resistance to radioactive contamination of deciduous forest was 10-20 times greater than that of conifers. We studied the irradiation doses of the different groups of organisms living in the various forest storeys, and the effects of irradiation (changes in species composition, prevalence and productivity) in communities of herbaceous plants and soil invertebrates. Specific examples are given to highlight the secondary changes in these communities stemming from radiation damage in species sensitive to radioactive contamination. We studied the dynamics of dispersion and migration of the long-lived radionuclides 90Sr and 137Cs in the various components of the biogeocenoses and in the network of geochemically interconnected forest landscapes, and their content in forestry produce. Some six to ten years after the deposition of radioactive fallout in forest ecosystems the radionuclides were more or less evenly spread throughout the soil-woody plant system. Thus, overall 90Sr content in the arboreal storey amounts to 1-2% in coniferous forests, and 5-10% in deciduous forests (Urals accident), while the corresponding figures for 137Cs (Chernobyl accident) are 2 to 3 times higher. (author)

  17. The French-German initiative for Chernobyl: programme 3: Health consequences of the Chernobyl accident

    - Goals: The main objectives of the health programme are collection and validation of existing data on cancer and non cancer diseases in the most highly contaminated regions of Ukraine, Russia and Belarus, common scientific expertise on main health indicators and reliable dosimetry, and finally communication of the results to the scientific community and to the public. - General Tasks: 1- Comparison between high and low exposed regions, 2- Description of trends over time, 3- Consideration of specific age groups. This methodological approach is applied on Solid cancer incidence and leukaemia incidence in different regions in Ukraine, Belarus and Russia, With a special focus on thyroid cancer in young exposed ages. - Thyroid cancer: Those exposed in very young ages continue to express a relatively high excess of thyroid cancer even though they have now reached the age group 15-29. Those exposed as young adults show a small increase, at least partly due to better screening conditions - Leukemia: Description of leukemia trends for various age groups show no clear difference between exposed and unexposed regions when focusing on those exposed at very young ages. The rates of childhood leukemia before and after the accident show no evidence of any increase (oblasts in Belarus over 1982-1998). - Specific studies: Incidence of congenital malformations in Belarus; Infant mortality and morbidity in the most highly contaminated regions; Potential effects of prenatal irradiation on the brain as a result of the Chernobyl accident; Nutritional status of population living in regions with different levels of contamination; Dosimetry of Chernobyl clean-up workers; Radiological passports in contaminated settlements. - Congenital malformations: As a national register was existing since the 1980's and gives the possibility to compare trends before and after the accident, results of congenital malformations describe large results collected over Belarus, There is no evidence of a

  18. Food monitoring for radioactivity concentrations after the Chernobyl accident: Consequences for the citizen

    Radioactively contaminated food accounts for most of the radiation exposure after the Chernobyl reactor accident. Hence, food low in radiation will allow to kerb exposure. Precautions include a general identification of radioactivity contents in food commodities by industry and trade as well as preferential supply of pregnant women, nursing mothers and young children with low-activity food. Such food would have an acceptable level of 10 Bq Cs 137/kg. Private precautions are needed for as long as the government fails to initiate corresponding measures. (DG)

  19. Environmental consequences of the Chernobyl accident and their remediation: 20 years of experience

    The Chernobyl Forum was organized by the United Nations to examine the health and environmental effects of the accident at the Chernobyl Nuclear Power Station Unit Number 4. This paper is concerned with the environmental effects, including human exposure, as determined by the Expert Group on Environment. The accident on 26 April 1986 resulted in the release of a large amount of radioactive materials over a period of ten days. These materials were deposited throughout Europe (and to a minor extent throughout the remainder of the northern hemisphere) with the three more affected countries being Belarus, the Russian Federation and Ukraine. The more important radionuclides from a human dosimetric standpoint were 131I, 134Cs and 137Cs, with half-lives of 8 d, 2 a and 30 a, respectively. More than five million persons lived on territories in these three countries judged to be contaminated at >37 kBq/m2. Many countermeasures were employed to mitigate the effects of the accident, with the main focus being on urban and agricultural areas. The collective effective dose to the residents of the contaminated territories is estimated to be about 55 000 man Sv; the collective thyroid dose is estimated to be 1.6 x 106 man Gy. Effects on non-human biota were observed that ranged from minor to lethal; a notable effect was the killing of a pine forest near the accident site. The current increase in the number and diversity of species in the most contaminated area is due to the absence of human pressure. The current shelter over the damaged reactor was constructed under time pressure, and it has significant leakage or airborne radionuclides and inflow of rainwater. The immediate waste management practices were chaotic and remediation is needed. It is planned to build an NSC structure over the top of the existing structure and to eventually dismantle the damaged reactor. This will put additional pressure on waste management, including the need for a new site for geologic disposal of

  20. Development of hydrogeological modelling approaches for assessment of consequences of hazardous accidents at nuclear power plants

    This paper introduces some modeling approaches for predicting the influence of hazardous accidents at nuclear reactors on groundwater quality. Possible pathways for radioactive releases from nuclear power plants were considered to conceptualize boundary conditions for solving the subsurface radionuclides transport problems. Some approaches to incorporate physical-and-chemical interactions into transport simulators have been developed. The hydrogeological forecasts were based on numerical and semi-analytical scale-dependent models. They have been applied to assess the possible impact of the nuclear power plants designed in Russia on groundwater reservoirs

  1. Study on consequences of radioactive iodine pollution and iodine prophylaxis after Chernobyl accident in Cracow region

    Program of investigations of effects of radiation and iodine prophylaxis undertaken after Chernobyl accident in Cracow region had to be modified due to goiter endemic in this region.These modifications included: 1) Division of the region into 3 areas (voivodeship Nowy Sacz, urban voivodeship Cracow and area of Kielce and Swietokrzyskie Mountains). 2) Study on iodine uptake in food and urinary secretion. 3) Examination of iodine level in drinking water, and an attempt of calculation of radiation dose absorbed by thyroid. Characterization of selected areas, principles of selection of study groups are presented as well as organisational details and methods of data collection. (author). 11 refs, 2 tabs

  2. Updated action plan for the implementation of measures as a consequence of the Fukushima reactor accident

    The action plan of the German government concerning the measures following the Fukushima reactor accident include the decision on the future of nuclear power in Germany, safety analyses, investigations and measures for nuclear power plants in a national frame, investigations in an international frame, planning for the implementation of CNS (Convention on nuclear safety) topics 1-3, i.e. measures to increase the robustness in German nuclear power plants, and the planning of implementation of further measures (CNS topics 4-6).

  3. Calculation notes that support accident scenario and consequence determination of a waste tank criticality

    The purpose of this calculation note is to provide the basis for criticality consequences for the Tank Farm Safety Analysis Report (FSAR). Criticality scenario is developed and details and description of the analysis methods are provided

  4. A synergistic use of CFD, experiments and effective convectivity model to reduce uncertainty in BWR severe accident analysis

    In a previous work we presented an analysis approach developed to effectively and accurately assess thermal loads on vessel and structures in a Boiling Water Reactor (BWR) lower head during a severe accident. Central to the assessment is the Effective Convectivity Model (ECM) that makes use of experimental heat transfer correlations to capture the effect of turbulent natural convection in a volumetrically heated liquid pool, while retaining the pool three-dimensional energy splitting and ability to represent local heat transfer effects. Thanking to its features, the ECM is unique in enabling calculations of complex heat transfer phenomena during long severe accident transients that would not be otherwise feasible using higher-fidelity methods such as Computational Fluid Dynamics (CFD). Efficiency notwithstanding, the natural questions are: (i) how good are those ECM-calculated results, and, (ii) if required, what can be done (with the highest return-on-investment) to improve the quality of ECM prediction results. The approach refers to experiments and CFD simulations as the main resources to address (i) and (ii). However, validation of ECM against simulant-fluid experiments by itself does not reveal deficiencies (due to non-prototypicality factors). In the present work we focus on the use of CFD-based numerical 'experiments' to identify and quantify source of epistemic uncertainty in the calculated thermal loads due to modeling assumptions in ECM. Specifically, heat transfer correlations that underlie the ECM are obtained as surface-averaged (even though implemented as spatially distributed) and derived from experiments conducted at different geometries and using fluids that are not reactor prototypical (molten corium in the present case of severe accident). The CFD simulations exhibit so-called fluid Prandtl number effect on local peaking of the pool's downward heat flux for corium as working fluid. The main premise is a synergistic use of a fast-running model

  5. Evaluating the consequences of loss of flow accident for a typical VVER-1000 nuclear reactor

    Mirvakili, S.M.; Safaei, S. [Shiraz Univ., Shiraz (Iran, Islamic Republic of). Dept. of Nuclear Engineering, School of Mechanical Engineering; Faghihi, F. [Shiraz Univ., Shiraz (Iran, Islamic Republic of). Safety Research Center

    2010-07-01

    The loss of coolant flow in a nuclear reactor can result from a mechanical or electrical failure of the coolant pump. If the reactor is not tripped promptly, the immediate effect is a rapid increase in coolant temperature, decrease in minimum departure from nucleate boiling ratio (DNBR) and fuel damage. This study evaluated the shaft seizure of a reactor coolant pump in a VVER-1000 nuclear reactor. The locked rotor results in rapid reduction of flow through the affected reactor coolant loop and in turn leads to an increase in the primary coolant temperature and pressure. The analysis was conducted with regard for superimposing loss of power to the power plant at the initial accident moment. The required transient functions of flow, pressure and power were obtained using system transient calculations applied in COBRA-EN computer code in order to calculate the overall core thermal-hydraulic parameters such as temperature, critical heat flux and DNBR. The study showed that the critical period for the locked rotor accident is the first few seconds during which the maximum values of pressure and temperature are reached. 10 refs., 1 tab., 3 figs.

  6. Managing Errors to Reduce Accidents in High Consequence Networked Information Systems

    Ganter, J.H.

    1999-02-01

    Computers have always helped to amplify and propagate errors made by people. The emergence of Networked Information Systems (NISs), which allow people and systems to quickly interact worldwide, has made understanding and minimizing human error more critical. This paper applies concepts from system safety to analyze how hazards (from hackers to power disruptions) penetrate NIS defenses (e.g., firewalls and operating systems) to cause accidents. Such events usually result from both active, easily identified failures and more subtle latent conditions that have resided in the system for long periods. Both active failures and latent conditions result from human errors. We classify these into several types (slips, lapses, mistakes, etc.) and provide NIS examples of how they occur. Next we examine error minimization throughout the NIS lifecycle, from design through operation to reengineering. At each stage, steps can be taken to minimize the occurrence and effects of human errors. These include defensive design philosophies, architectural patterns to guide developers, and collaborative design that incorporates operational experiences and surprises into design efforts. We conclude by looking at three aspects of NISs that will cause continuing challenges in error and accident management: immaturity of the industry, limited risk perception, and resource tradeoffs.

  7. Estimation of health in Chernobyl NPP accident consequences cleaning-up participants

    Over 11 years period of health observation of Chernobyl Accident's victims permits to make some conclusions. Quantitative changes of peripheral blood and bone marrow cells, changes in ultrastructural organization of hemopoietic cells, disturbance of proliferative activity of hemopoietic and stromal progenitor cells in clean-up workers testify to alterations of functional properties of hemopoiesis. There are high level of T- helpers, early appearance regenerated T-cells, which simultaneously express surface antigens of helpers and supressors, synchronization of proliferative cycle of immunocompetentive cells in these patients. Oppressing of antioxidant protection, stable changes of hormonal maintenance of adaptation and reproduction processes, disturbance of feedback mechanism between effector glands and hypophysis, significant rise of polyamines were determined. Cardiovascular diseases are the principal cause of health disruptions at victims. Neural and psychological diseases, suicidal cases, trauma, death in automobile accidents are rank second and third in structure of morbidity. In structure of chronic nonspecific pulmonary diseases dominated chronic obstructive bronchitis. The adrenergic tonus of vegetative nervous system was seen. The peculiarity of rehabilitation measures is complexness and continuity in-patients, out-patients service and providing facilities in health resorts. (author)

  8. Early clinical consequences of victims in JCO criticality accident in Tokaimura

    The JCO criticality accident occurred at 10:35 on September 30, 1999 when two workers (O and S) poured the solution of uranyl nitrate into the precipitation tank and one (Y) worked at desk in the neighboring room. O's symptoms were unconsciousness, rigidity and emesis, and S's, numbness. The three were moved to Mito National Hospital by an ambulance car at 12:07 and then to the Hospital of National Institute of Radiological Sciences by the helicopter and car at 15:25, where contamination of their cloths by Na-24, suggesting the exposure to neutron, was found. O exhibited emesis within 10 min after the accident and diarrhea, unconsciousness and severe pyrexia within 1 hr, suggesting he had undergone the lethal exposure of >8 Gy. S showed emesis, light unconsciousness and numbness within 1 hr, suggesting >6 Gy and Y did not show even emesis, less dose exposure than the two. They underwent firstly the drip of sodium hydrogen carbonate (due to possible internal exposure of uranium), oxygen inhalation and then corticoid injection as well as the drip of antibiotics. At that day, they had the special therapy with pentoxyphylline and L-glutamine+elementary diet. Later, in the Hospital of Tokyo University, O and S had the heamopoietic stem cell transplantation. At present, O passed away, S is still in hospital and Y is discharged. (K.H.)

  9. Medical consequences of the Kyshtym radiation accident of 29 September 1957

    As a result of the accidental release of long-lived radionuclides, the gamma-radiation dose rate in the near zone of the trail reached tens of cGy per hour and, in a number of populated areas in the open countryside, 0.1 c Gy x hour-1. The evacuation of 10 730 people reduced the possible radiation doses by 2-24 times. Examination of people who had received the highest effective dose equivalents prior to evacuation (2.3-52 cSv) revealed, in the first two years, instability in leukocytes and thrombocytes (used as indicators), but this did not exceed normal fluctuations. The structure of morbidity and mortality among the adult and child populations and the incidence of congenital pathology and infant mortality do not differ from the control. The proportion of families with children born of parents aged between 10 and 30 at the time of the accident does not differ from the same indicators for the whole of the USSR, and, in the case of those aged between 0 and 9 years at the time of the accident, this proportion is 5-10% lower than control values, although the number of people who married is considerably higher than in the control group. In addition, the standardized birthrate coefficients in the study group (31.8 x 10-3) are considerably higher than in the control group (18.4 x 10-3). (author)

  10. The ecological consequences of transuranium elements realize on Belarus as a result of Chernobyl NPP accident

    The levels of radioactive contamination with transuranium elements (TUE) on territory of Belarus as a result of nuclear weapon tests and Chernobyl NPP accident have been assessed . The uniform contamination of soil with level of 53±17 Bq/m2 for Pu-239+240 was formed as a result of global precipitation after the nuclear weapon test. This value increased up to 1.1·105 Bq/m2 in South regions of Belarus and gradually decreased to level of global fall out on the North of the republic after Chernobyl NPP accident. The study of the atmosphere contamination with TUE in Republic of Belarus is being held since 1980 to now. The mechanism of radioactive air pollution from April, 1986 is determined by dust transfer from radioactive contaminated regions. The value of this transfer is influenced considerably by agricultural activities on contaminated territory, forest fires and other anthropogenic factors. The transfer coefficients in the soil-plant system have plant species dependence. The behavior of TUE in environment is discussed. (Authors)

  11. Proceedings of the first part of a joint OECD(NEA)/CEC workshop on recent advances in reactor accident consequence assessment

    The first part of the Joint Workshop, organised by the NEA, is focused on the progress achieved in the work of CSNI's GRECA (Group of Experts on Accident Consequences). The program is composed of the following papers. Session 1: characteristics of the Chernobyl release and fallout that affect transport and behaviour of radioactive substances in the environment; Chernobyl accident and hot particles in the fallout; radionuclides associated with colloids and particles in the Chernobyl fallout; source term in the Chernobyl accident; long range transport of radionuclides; parameters in consequence calculations for an urban area. Session 2: review of evaluations concerning radionuclide transfer to foodstuffs via plants in view of the data available after the Chernobyl accident; GRECA review of Chernobyl data on transfer to animal products; Chernobyl accident radiometric data (Cs-137 in fresh water fishes of north Italy lakes); distribution of Cs-137 in water sediment and fish in the Ijsselmeer (Netherlands); uptake in the human body resulting from the Chernobyl accident; radioactivity of people in the nordic countries following the Chernobyl accident; preparations for an international study to evaluate long-range transport models against the Chernobyl accident

  12. Accidents - Chernobyl accident; Accidents - accident de Tchernobyl

    NONE

    2004-07-01

    This file is devoted to the Chernobyl accident. It is divided in four parts. The first part concerns the accident itself and its technical management. The second part is relative to the radiation doses and the different contaminations. The third part reports the sanitary effects, the determinists ones and the stochastic ones. The fourth and last part relates the consequences for the other European countries with the case of France. Through the different parts a point is tackled with the measures taken after the accident by the other countries to manage an accident, the cooperation between the different countries and the groups of research and studies about the reactors safety, and also with the international medical cooperation, specially for the children, everything in relation with the Chernobyl accident. (N.C.)

  13. Radiocontamination patterns and possible health consequences of the accident at the Chernobyl nuclear power station

    The main hazard in the early phase after Chernobyl was radioiodine. Thyroid doses were esimated separately for (i) zones of strict control, (ii) most contaminated provinces (iii) the whole central European region of the USSR. Distinction was made between children under the age of 7 years at the time of the accident and the rest of the population. In the later phase the main concern is whole-body exposure to radiocaesium. Doses were calculated for the same areas and age groups as radioiodine. The following were considered: thyroid malignancies, leukaemia, other types of cancer, genetic defects and teratogenic anomalies. A stastistically significant excess over the spontaneous level is unlikely to be detectable for these effects, with the possible exception of thyroid disorders. The risk was greatly reduced by preventive measures, in particular lifetime doses have been restricted by establishment of a limit of 0.35 Sv. (author)

  14. Health effects models for off-site radiological consequence analysis of nuclear reactor accidents

    A first version of models has been developed for predicting the number of occurrences of health effects induced by radiation exposure in nuclear reactor accidents. The models are based on the health effects models developed originally by Harvard University (NUREG/CR-4214). These models are revised on the basis of the new information on risk estimates by the reassessment of the radiation dosimetry in Hiroshima and Nagasaki. The models deal with the following effects: (1) early effects models for bone marrow, lungs, gastrointestinal tract, central nervous system, thyroid, skin and reproductive organs, using the Weibull function, (2) late somatic effects models including leukemia and cancers of breast, lungs, thyroid, gastrointestinal tract and so forth, on the basis of the information derived from epidemiological studies on the atomic bomb survivors of Hiroshima and Nagasaki, (3) models for late and developmental effects due to exposure in utero. (author)

  15. Probability and consequences of severe reactor accidents. 60th year atw

    Rasmussen, Norman Carl [Massachusetts Institute of Technology (MIT), Cambridge, MA (United States). Dept. of Nuclear Engineering

    2015-06-15

    The study carried out on behalf of former USAEC (United States Atomic Energy Commission) led by Prof. Rasmussen and published in reworked form as WASH 1400 by the USNRC (United States Nuclear Regulatory Commission) in 1975, assessed in 3,300 pages the risks that can be deducted from severe accidents in nuclear power plants. The results, often quoted and criticised, were so far the most conclusive statements to this question. In his lecture at the reactor meeting in 1976, Prof. Rasmussen tried to trace back the conclusion of the results to the question: Is the use of larger nuclear power plants, in accordance to experiences and calculations so far, acceptable? His risk assessment, related to American power plants and cites, on behalf of the BMI is currently evaluated by the IRS together with the LRA on specific occurrences within the Federal Republic of Germany.

  16. The French-German initiative for Chernobyl: programme 3: Health consequences of the Chernobyl accident

    Tirmarche, M. [Institut de Radioprotection et de Surete Nucleaire (IRSN), Radiological Protection and Human Health Div. (DRPH), Radiobiology and Epidemiology Dept., 92 - Fontenay-aux-Roses (France); Kellerer, A.M. [Munchen Univ., Strahlenbiologisches Institut (Germany); Bazyka, D. [Chornobyl Center (CC), Kiev regoin (Ukraine)

    2006-07-01

    - Goals: The main objectives of the health programme are collection and validation of existing data on cancer and non cancer diseases in the most highly contaminated regions of Ukraine, Russia and Belarus, common scientific expertise on main health indicators and reliable dosimetry, and finally communication of the results to the scientific community and to the public. - General Tasks: 1- Comparison between high and low exposed regions, 2- Description of trends over time, 3- Consideration of specific age groups. This methodological approach is applied on Solid cancer incidence and leukaemia incidence in different regions in Ukraine, Belarus and Russia, With a special focus on thyroid cancer in young exposed ages. - Thyroid cancer: Those exposed in very young ages continue to express a relatively high excess of thyroid cancer even though they have now reached the age group 15-29. Those exposed as young adults show a small increase, at least partly due to better screening conditions - Leukemia: Description of leukemia trends for various age groups show no clear difference between exposed and unexposed regions when focusing on those exposed at very young ages. The rates of childhood leukemia before and after the accident show no evidence of any increase (oblasts in Belarus over 1982-1998). - Specific studies: Incidence of congenital malformations in Belarus; Infant mortality and morbidity in the most highly contaminated regions; Potential effects of prenatal irradiation on the brain as a result of the Chernobyl accident; Nutritional status of population living in regions with different levels of contamination; Dosimetry of Chernobyl clean-up workers; Radiological passports in contaminated settlements. - Congenital malformations: As a national register was existing since the 1980's and gives the possibility to compare trends before and after the accident, results of congenital malformations describe large results collected over Belarus, There is no evidence of a

  17. Parameters of peroxidation and proteolysis in the organism of the liquidators of Chernobyl accident consequences.

    Lykholat, E A; Chernaya, V I

    1999-01-01

    The specificity of lung irradiation caused by ionizing radiation is influence on mucous membranes of respiratory ways, alveolar epithelium and capillaries of a small circle of the blood circulation. Under diseases of bronchus-lung system the lipid peroxidation (LPO) processes activation is observed. The radiating influence strengthening effect. In results in imbalance aggravation in system "LPO-antioxidants", and long expressing of LPO intensification is the important mechanism of the inflammation chronization. The sharp increase of proteolytic activity and inhibitor activity decrease is found out in the patients-liquidators. Noticed imbalance results in the further change of permeability of membranes and correlates with an index of endoscopy inflammation changes and index of irreversible changes in lung tissue. Thus, the direct connection between LPO intensity and imbalance degree of proteinase-inhibitor system of blood at the patients with chronic bronchitic taking part in Chernobyl accident liquidation is revealed. PMID:10609329

  18. Probability and consequences of severe reactor accidents. 60th year atw

    The study carried out on behalf of former USAEC (United States Atomic Energy Commission) led by Prof. Rasmussen and published in reworked form as WASH 1400 by the USNRC (United States Nuclear Regulatory Commission) in 1975, assessed in 3,300 pages the risks that can be deducted from severe accidents in nuclear power plants. The results, often quoted and criticised, were so far the most conclusive statements to this question. In his lecture at the reactor meeting in 1976, Prof. Rasmussen tried to trace back the conclusion of the results to the question: Is the use of larger nuclear power plants, in accordance to experiences and calculations so far, acceptable? His risk assessment, related to American power plants and cites, on behalf of the BMI is currently evaluated by the IRS together with the LRA on specific occurrences within the Federal Republic of Germany.

  19. Uncertainties in geologic disposal of high-level wastes - groundwater transport of radionuclides and radiological consequences

    The analysis for radionuclide transport in groundwater considers models and methods for characterizing (1) the present geologic environment and its future evolution due to natural geologic processes and to repository development and waste emplacement, (2) groundwater hydrology, (3) radionuclide geochemistry, and (4) the interactions among these phenomena. The discussion of groundwater transport focuses on the nature of the sources of uncertainty rather than on quantitative estimates of their magnitude, because of the lack of evidence that current models can provide realistic quantitative predictions of radionuclide transport in groundwater for expected repository environments. The analysis for the long-term health risk to man following releases of long-lived radionuclides to the biosphere is more quantitative and involves estimates of uncertainties in (1) radionuclide concentrations in man's exposure environment, (2) radionuclide intake by exposed individuals per unit concentration in the environment, (3) the dose per unit intake, (4) the number of exposed individuals, and (5) the health risk per unit dose. For the important long-lived radionuclides in high-level waste, uncertainties in most of the different components of a calculation of individual and collective dose per unit release appear to be no more than two or three orders of magnitude; these uncertainties are certainly much less than uncertainties in predicting groundwater transport of radionuclides between a repository and the biosphere. Several limitations in current models for predicting the health risk to man per unit release to the biosphere are discussed

  20. IRSN press briefing on the issue 'Fukushima, one year after': Situation of Fukushima Dai-ichi nuclear installations; Accident of the Fukushima Dai-ichi: briefing on the situation in February 2012; The Fukushima 1 accident one year after: assessment of environmental consequences in Japan; assessment of consequences of the Fukushima accident on the environment in Japan, one year after; Health consequences of the Fukushima Dai-ichi: situation briefing in February 2012

    This document gathers reports and Power Point presentations (with maps, data tables and graphs) dealing with the Fukushima accident, one year after its occurrence. Different issues are addressed: the status of the nuclear installations, the situation of the installations and of the environment, assessments, measurements and investigations on the effects and consequences of the accident (radioactive releases and fallouts) on the ground and marine environment and on public health

  1. Help guides for post-accident consequence management: farm activities and exiting the emergency phase; Les guides d'aide a la gestion des consequences post-accidentelles: activites agricoles et sortie de la phase d'urgence

    Cessac, B.; Reales, N. [Institut de Radioprotection et de Surete Nucleaire, BP 17 - 92262 Fontenay-aux-Roses (France); Mehl-Auget, I. [Autorite de Surete Nucleaire - 6, place du Colonel Bourgoin - 75012 Paris (France)

    2010-07-01

    After having recalled the main actions foreseen in the PPIs (plans particuliers d'intervention, intervention specific plans) in case of radionuclide release in the environment after a nuclear accident, i.e. sheltering and ingestion of steady iodine, and also indicated the different phases of consequence management (preparation, emergency and post-accident phases), this report describes and comments the contents of two guides published by the IRSN (the French Radioprotection and Nuclear Safety Institute) and dealing with the management of post-accident consequences. The first one is a guide to aid to decision-making for the management of the agricultural sector in case of nuclear accident, and the second one is a guide for the preparation of the end of the emergency phase in which actions to be performed during the first week after the end of accidental releases are described

  2. An overview of current knowledge concerning the health and environmental consequences of the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident.

    Aliyu, Abubakar Sadiq; Evangeliou, Nikolaos; Mousseau, Timothy Alexander; Wu, Junwen; Ramli, Ahmad Termizi

    2015-12-01

    Since 2011, the scientific community has worked to identify the exact transport and deposition patterns of radionuclides released from the accident at the Fukushima Daiichi Nuclear Power Plant (FDNPP) in Japan. Nevertheless, there still remain many unknowns concerning the health and environmental impacts of these radionuclides. The present paper reviews the current understanding of the FDNPP accident with respect to interactions of the released radionuclides with the environment and impacts on human and non-human biota. Here, we scrutinize existing literature and combine and interpret observations and modeling assessments derived after Fukushima. Finally, we discuss the behavior and applications of radionuclides that might be used as tracers of environmental processes. This review focuses on (137)Cs and (131)I releases derived from Fukushima. Published estimates suggest total release amounts of 12-36.7PBq of (137)Cs and 150-160PBq of (131)I. Maximum estimated human mortality due to the Fukushima nuclear accident is 10,000 (due to all causes) and the maximum estimates for lifetime cancer mortality and morbidity are 1500 and 1800, respectively. Studies of plants and animals in the forests of Fukushima have recorded a range of physiological, developmental, morphological, and behavioral consequences of exposure to radioactivity. Some of the effects observed in the exposed populations include the following: hematological aberrations in Fukushima monkeys; genetic, developmental and morphological aberrations in a butterfly; declines in abundances of birds, butterflies and cicadas; aberrant growth forms in trees; and morphological abnormalities in aphids. These findings are discussed from the perspective of conservation biology. PMID:26425805

  3. Comparison of MACCS users calculations for the international comparison exercise on probabilistic accident consequence assessment code, October 1989--June 1993

    Neymotin, L. [Brookhaven National Lab., Upton, NY (United States)

    1994-04-01

    Over the past several years, the OECD/NEA and CEC sponsored an international program intercomparing a group of six probabilistic consequence assessment (PCA) codes designed to simulate health and economic consequences of radioactive releases into atmosphere of radioactive materials following severe accidents at nuclear power plants (NPPs): ARANO (Finland), CONDOR (UK), COSYMA (CEC), LENA (Sweden), MACCS (USA), and OSCAAR (Japan). In parallel with this effort, two separate groups performed similar calculations using the MACCS and COSYMA codes. Results produced in the MACCS Users Group (Greece, Italy, Spain, and USA) calculations and their comparison are contained in the present report. Version 1.5.11.1 of the MACCS code was used for the calculations. Good agreement between the results produced in the four participating calculations has been reached, with the exception of the results related to the ingestion pathway dose predictions. The main reason for the scatter in those particular results is attributed to the lack of a straightforward implementation of the specifications for agricultural production and counter-measures criteria provided for the exercise. A significantly smaller scatter in predictions of other consequences was successfully explained by differences in meteorological files and weather sampling, grids, rain distance intervals, dispersion model options, and population distributions.

  4. Potential consequences in Norway after a hypothetical accident at Leningrad nuclear power plant. Potential release, fallout and predicted impacts on the environment

    Nalbandyan, A.; Ytre-Eide, M.A.; Thoerring, H.; Liland, A.; Bartnicki, J.; Balonov, M.

    2012-06-15

    The report describes different hypothetical accident scenarios at the Leningrad nuclear power plant for both RBMK and VVER-1200 reactors. The estimated release is combined with different meteorological scenarios to predict possible fallout of radioactive substances in Norway. For a hypothetical catastrophic accident at an RBMK reactor combined with a meteorological worst case scenario, the consequences in Norway could be considerable. Foodstuffs in many regions would be contaminated above the food intervention levels for radioactive cesium in Norway. (Author)

  5. Potential consequences in Norway after a hypothetical accident at Leningrad nuclear power plant. Potential release, fallout and predicted impacts on the environment

    The report describes different hypothetical accident scenarios at the Leningrad nuclear power plant for both RBMK and VVER-1200 reactors. The estimated release is combined with different meteorological scenarios to predict possible fallout of radioactive substances in Norway. For a hypothetical catastrophic accident at an RBMK reactor combined with a meteorological worst case scenario, the consequences in Norway could be considerable. Foodstuffs in many regions would be contaminated above the food intervention levels for radioactive cesium in Norway. (Author)

  6. An assessment of the radiological consequences of releases to groundwater following a core-melt accident at the Sizewell PWR

    In the extremely unlikely event of a degraded core accident at the proposed Sizewell PWR it is theoretically possible for the core to melt through the containment, after which activity could enter groundwater directly or as a result of subsequent leaching of the core in the ground. The radiological consequences of such an event are analysed and compared with the analysis undertaken by the NRPB for the corresponding releases to atmosphere. It is concluded that the risks associated with the groundwater route are much less important than those associated with the atmospheric route. The much longer transport times in the ground compared with those in the atmosphere enable countermeasures to be taken, if necessary, to restrict doses to members of the public to very low levels in the first few years following the accident. The entry of long-lived radionuclides into the sea over very long timescales results in the largest contribution to population doses, but these are delivered at extremely low dose rates which would be negligible compared with background exposure. (author)

  7. Health effects models for nuclear power plant accident consequence analysis. Part 1, Introduction, integration, and summary: Revision 2

    Evans, J.S. [Harvard School of Public Health, Boston, MA (United States); Abrahmson, S. [Wisconsin Univ., Madison, WI (United States); Bender, M.A. [Brookhaven National Lab., Upton, NY (United States); Boecker, B.B.; Scott, B.R. [Inhalation Toxicology Research Inst., Albuquerque, NM (United States); Gilbert, E.S. [Battelle Pacific Northwest Lab., Richland, WA (United States)

    1993-10-01

    This report is a revision of NUREG/CR-4214, Rev. 1, Part 1 (1990), Health Effects Models for Nuclear Power Plant Accident Consequence Analysis. This revision has been made to incorporate changes to the Health Effects Models recommended in two addenda to the NUREG/CR-4214, Rev. 1, Part 11, 1989 report. The first of these addenda provided recommended changes to the health effects models for low-LET radiations based on recent reports from UNSCEAR, ICRP and NAS/NRC (BEIR V). The second addendum presented changes needed to incorporate alpha-emitting radionuclides into the accident exposure source term. As in the earlier version of this report, models are provided for early and continuing effects, cancers and thyroid nodules, and genetic effects. Weibull dose-response functions are recommended for evaluating the risks of early and continuing health effects. Three potentially lethal early effects -- the hematopoietic, pulmonary, and gastrointestinal syndromes are considered. Linear and linear-quadratic models are recommended for estimating the risks of seven types of cancer in adults - leukemia, bone, lung, breast, gastrointestinal, thyroid, and ``other``. For most cancers, both incidence and mortality are addressed. Five classes of genetic diseases -- dominant, x-linked, aneuploidy, unbalanced translocations, and multifactorial diseases are also considered. Data are provided that should enable analysts to consider the timing and severity of each type of health risk.

  8. Review, analysis and report on the radiological consequences resulting from accidents and incidents involving radioactive materials during transport in the period 1975-1986 by and within member states of the european communities

    Radioactive materials are routinely transported throughout the European Communities, by all modes of transport. These shipments occur in accordance with comprehensive regulations and the vast majority of these shipments are made without incident. Occasionally however accidents and other incidents have occurred at various stages of transport operations and the purpose of this study was to examine the available information on events that occurred within the Communities during the years 1975 to 1986. The information was gathered from Member States' Competent Authorities and other organisations, using a questionnaire. Most of the detailed information came from the two countries carrying out the study, the UK and France. The information gathered covered many different types of event involving a wide range of materials: it is concluded that under-reporting is a major source of uncertainty in the results. Therefore, it is emphasised that care should be used in comparisons between the results for different types of transport operations, since accidents and incidents involving certain types of transport are more fully reported than others. Consequently, the authors stress the need for improved reporting and recording procedures. No evidence was found of any major health consequences resulting from the accidents and incidents studied. However, there were instances of high doses having been received by workers, mainly as a result of inadequate preparation of packages prior to despatch. These events point to the need to maintain high standards of quality assurance at all stages of transport operations

  9. Health effects models for nuclear power plant accident consequence analysis: Low LET radiation

    This report describes dose-response models intended to be used in estimating the radiological health effects of nuclear power plant accidents. Models of early and continuing effects, cancers and thyroid nodules, and genetic effects are provided. Weibull dose-response functions are recommended for evaluating the risks of early and continuing health effects. Three potentially lethal early effects -- the hematopoietic, pulmonary, and gastrointestinal syndromes -- are considered. In addition, models are included for assessing the risks of several nonlethal early and continuing effects -- including prodromal vomiting and diarrhea, hypothyroidism and radiation thyroiditis, skin burns, reproductive effects, and pregnancy losses. Linear and linear-quadratic models are recommended for estimating cancer risks. Parameters are given for analyzing the risks of seven types of cancer in adults -- leukemia, bone, lung, breast, gastrointestinal, thyroid, and ''other.'' The category, ''other'' cancers, is intended to reflect the combined risks of multiple myeloma, lymphoma, and cancers of the bladder, kidney, brain, ovary, uterus and cervix. Models of childhood cancers due to in utero exposure are also developed. For most cancers, both incidence and mortality are addressed. The models of cancer risk are derived largely from information summarized in BEIR III -- with some adjustment to reflect more recent studies. 64 refs., 18 figs., 46 tabs

  10. Health effects models for nuclear power plant accident consequence analysis: Low LET radiation

    Evans, J.S. (Harvard Univ., Boston, MA (USA). School of Public Health)

    1990-01-01

    This report describes dose-response models intended to be used in estimating the radiological health effects of nuclear power plant accidents. Models of early and continuing effects, cancers and thyroid nodules, and genetic effects are provided. Weibull dose-response functions are recommended for evaluating the risks of early and continuing health effects. Three potentially lethal early effects -- the hematopoietic, pulmonary, and gastrointestinal syndromes -- are considered. In addition, models are included for assessing the risks of several nonlethal early and continuing effects -- including prodromal vomiting and diarrhea, hypothyroidism and radiation thyroiditis, skin burns, reproductive effects, and pregnancy losses. Linear and linear-quadratic models are recommended for estimating cancer risks. Parameters are given for analyzing the risks of seven types of cancer in adults -- leukemia, bone, lung, breast, gastrointestinal, thyroid, and other.'' The category, other'' cancers, is intended to reflect the combined risks of multiple myeloma, lymphoma, and cancers of the bladder, kidney, brain, ovary, uterus and cervix. Models of childhood cancers due to in utero exposure are also developed. For most cancers, both incidence and mortality are addressed. The models of cancer risk are derived largely from information summarized in BEIR III -- with some adjustment to reflect more recent studies. 64 refs., 18 figs., 46 tabs.

  11. Economic consequences of the Chernobyl accident in Norway in the decade 1986-1995

    Although the distance from Chernobyl to Norway is about 2000 km, it is estimated that 3-5% of the radiocesium released from Chernobyl was deposited upon Norwegian territory. This was caused by an unfortunate (for Norway) and unusual combination of large initial thermal lift of the plume (which kept the materials airborne), wind direction (which brought the plume across Scandinavia), and precipitation (which led to strong deposition in parts of Norway and Sweden). The areas in which deposition took place in Norway to a large extent comprise natural environments (mountain plains and forest) which are important in an agricultural context. In 1986, large amounts of mutton, reindeer meat and goat's cheese exceeded the limits for radiocesium content set by the authorities. Some non-destructive countermeasures were implemented, but much of the meat was condemned. By the following year the authorities had implemented a large programme of countermeasures, and thereby managed drastically to reduce the amount of discarded food. In the present report, the cost of these countermeasures, as well as the cost of discarded foodstuff, is summarized for each of the ten years since the accident. Although ten years have passed, all the countermeasures are still required, even though there has been some decline in the size of the areas and the number of animals involved. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  12. Accident consequence calculations and risk assessments for pressurized light water reactors with the computer code UFOMOD/B3

    With respect to the application of the accident consequence model of the German Risk Study (GRS) for light water reactors to risk assessments of other reactor types (high temperature reactor HTR-1160, fast breeder reactor SNR-300), the improved version UFOMOD/B3 was developed. The modifications mainly concern the deposition parameters, the resuspension process, the ingestion model and the dose factors. To make results comparable, recalculations for pressurized light water reactors were performed with the release categories of the GRS. The results show in contrast to the findings of the GRS a significant reduction of the acute fatality risk by a factor of 3.6. This essentially results from the smaller deposition parameters. The latent fatality risk was calculated nearly unchanged. (orig.)

  13. Radiological and dosimetric consequences in case of nuclear accident: taking them into account within the security approach and protection challenges; Consequences radiologiques et dosimetriques en cas d'accident nucleaire: prise en compte dans la demarche de surete et enjeux de protection

    Cogez, E.; Herviou, K.; Isnard, O.; Cessac, B.; Reales, N.; Quentric, E.; Quelo, D. [Institut de Radioprotection et de Surete Nucleaire, Direction de l' Environnement et de l' Intervention, Service des Situations d' Urgence et d' Organisation de Crise, BP 17 - 92262 Fontenay-aux-Roses (France)

    2010-07-01

    This report first proposes a presentation of the 'defence in depth' concept which comprises five as much as possible independent levels: preventing operation anomalies and system failures, maintaining the installation within the authorized domain, controlling accidents within design hypotheses, preventing the degradation of accidental conditions and limiting consequences of severe accidents, limiting radiological consequences for population in case of important releases. Then, after a description of a release atmospheric dispersion and of its consequences, this report describes the consequences of two accident scenarios. The first accident is a failure of steam generator tubes, and the second a loss of primary coolant. It notably indicates the main released radionuclides, exposure levels at different distance for a given set of dispersion conditions

  14. Current status and epidemiological research needs for achieving a better understanding of the consequences of the Chernobyl accident.

    Cardis, Elisabeth

    2007-11-01

    Twenty years after the Chernobyl accident, there is no clearly demonstrated increase in the incidence of cancers in the most affected populations that can be attributed to radiation from the accident, except for the dramatic increase in thyroid cancer incidence among those exposed in childhood and adolescence. Increases in the incidence of cancers and other diseases have been reported in Belarus, the Russian Federation, and Ukraine, but much of the increase appears to be due to other factors, including improvements in diagnosis, reporting, and registration. Recent findings indicate a possible doubling of leukemia risk among Chernobyl liquidators and a small increase in the incidence of premenopausal breast cancer in the very most contaminated districts. Increased risks of cardiovascular diseases and cataracts have also been reported. These findings, however, need confirmation in well-designed analytical epidemiological studies with careful individual dose reconstruction. The absence of demonstrated increases in cancer risk--apart from thyroid cancer--is not the proof that no increase has in fact occurred. Based on the experience of atomic bomb survivors, and assuming that there is a linear, no-threshold dose-response relationship between exposure to ionizing radiation and the development of cancer in humans, a small increase in the relative risk of cancer is expected, even at the low to moderate doses received. Given the large number of individuals exposed, the absolute number of cancer cases caused could be substantial, particularly in the future. It is therefore essential to continue to use population registries to monitor trends in disease morbidity and mortality in the most contaminated areas, as well as among liquidators, in order to assess the public health impact of the accident. Studies of selected populations and diseases are also essential in order to study the real effect of the accident and compare it to predictions. Careful studies may in particular

  15. Source term assessment, containment atmosphere control systems, and accident consequences. Report to CSNI by an OECD/NEA Group of experts

    CSNI Report 135 summarizes the results of the work performed by CSNI's Principal Working Group No. 4 on the Source Term and Environmental Consequences (PWG4) during the period extending from 1983 to 1986. This document contains the latest information on some important topics relating to source terms, accident consequence assessment, and containment atmospheric control systems. It consists of five parts: (1) a Foreword and Executive Summary prepared by PWG4's Chairman; (2) a Report on the Technical Status of the Source Term; (3) a Report on the Technical Status of Filtration and Containment Atmosphere Control Systems for Nuclear Reactors in the Event of a Severe Accident; (4) a Report on the Technical Status of Reactor Accident Consequence Assessment; (5) a list of members of PWG4

  16. Modeling and assessment of accident consequences; development of RODOS, a real-time on-line decision support system for nuclear emergencies in Europe

    In cooperation with NRPB (UK), the first version 1.0 of PC COSYMA for use on advanced PCs has been released; during a training course in mid 1993, future users were educated in operating the software. The main frame version of the program package COSYMA has been up-dated with new dose conversion factors and fodd-chain data and was distributed to some 20 institutes in Europe and abroad. The comparative calculations performed within the international OECD(NEA)/CEC intercomparison of accident consequence assessment codes were analysed and documented in three reports. Furtheron, consequence assessments have been performed for the research reactor BER II (two source terms) and documented; the influence on individual doses and emergency actions of inplant accident management measures in future EPRs was quantified; within th scope of a EC/US-study on the external costs of the energy cycle, accident consequences were assessed for three source terms. (orig.)

  17. Environmental and health consequences in Japan due to the accident at Chernobyl nuclear reactor plant

    A comprehensive review was made on the results of national monitoring program for environmental radioactivity in Japan resulting from the accident at the Chernobyl nuclear power plant in USSR. Period of monitoring efforts covered by the present review is from 30th of April 1986 to 31st of May 1987. A radioactive cloud released from the Chernobyl nuclear reactor initially arrived in Japan on 30th of April 1986 as indicated by the elevated level of 131I, 137Cs and 134Cs activity in the total deposition on 30th of April and also by the increased 137Cs body burden noted on 1st of May. Almost all the radioactive nuclides detected in the European countries were also identified in Japan. For example, the observed nuclides were: 95Zr, 95Nb, 99mTc, 103Ru, 106Ru, 110mAg, 111Ag, 125Sb, 127Sb, 129mTe, 131I, 132Te, 132I, 133I, 134Cs, 136Cs, 137Cs, 140Ba, 140La, 141Ce and 144Ce. Among the above radionuclides, the country average concentration was determined for 131I, 137Cs and 134Cs in various environmental materials such as air, fresh water, soil, milk, leafy and root vegetables, cereals, marine products and other foodstuffs. In contrast to the sharp decline of 131I which was negligible after a few months, 137Cs showed a tendency to maintain its activity in foodstuffs at an appreciable level one year later. Collective effective dose equivalent and dose equivalent to thyroid in Japanese population due to 137Cs, 134Cs and 131I were estimated to be around 590 man Sv and 4760 man Sv, respectively. Corresponding values for the per caput dose equivalent are 5 μSv for whole body and 40 μSv for thyroid, respectively. (author)

  18. Dermatological consequences of the Cs-137 radiological accident in Goiania, Goias State, Brazil

    The objective of the present study was to analyse the occurrence of dermatosis in individuals that had been exposed to cesium137 during the radioactive accident in Goiania, in 1987 and detect pre-cancerous dermatosis or those predictive of low immunity. The groups were evaluated according to the intensity of radiation they had been exposed to and then compared to a control group of people not exposed to radiation. The population exposed to the cesium137 was comprised of 109 people, who were divided into Groups I and II, according to the CNEN norms. In group I, 54 people with ≤ 20 rads exposure and/or radio lesion were included; in group II, 55 people with > 20 rads exposure were included, along with the children of group I individuals. This was a historic cohort study, that is, a retrospective study that lasted 9 years, extending from September of 1987 to August, 1996. The presence of the oncoprotein p-53 was studied in the radio lesions of 10 patients. There is no evidence of an increase in the incidence of dermatosis in the exposed groups, excepts for pyoderma in patients with radio lesions. The most frequent dermatosis were: pyoderma, pityriasis versicolor, scabies, dermatophytosis and seborrhoeic dermatitis. The results obtained were not statistically significant for the evaluation of dermatosis predictive of low immunity or precancerous lesions. The oncoprotein p-53 in individuals with radio lesion showed a 80% positivity rate and risk factor estimated in 8 times, for the test. It has proved to be useful because it represents one more option in terms of propaedeutic evaluation and suggests that one should pay close and continuous attention in order to better control the evolution of these individuals. (author)

  19. Preliminary thermal design of a pressurized water reactor containment for handling severe accident consequences

    A one-dimensional mathematical model has been developed for a 4250 MW(th) Advanced Pressurized Water Reactor containment analysis following a severe accident. The cooling process of the composite containment-steel shell and concrete shield- is achievable by natural circulation of atmospheric air. However, for purpose of gettering higher degrees of safety margin, the present study undertakes two objectives: (1) Installment of a diesel engine-driven air blower to force air through the annular space between the steel shell and concrete shield. The engine can be remotely operated to be effective in case of station blackout. (ii) Fixing longitudinally plate fins on the circumference of the inside and outside containment steel shell. These fins increase the heat transfer areas and hence the rate of heat removal from the containment atmosphere. In view of its importance - from the safety viewpoint - the long term behaviour of the containment which is a quasi-steady state problem, is formulated through a system of coupled nonlinear algebraic equations which describe the thermal-hydraulic and thermodynamic behaviour of the double shell containment. The calculated results revealed the following: (i) the passively air cooled containment can remove maximum heat load of 11.5 MW without failure, (ii) the effect of finned surface in the air passage tends to decrease the containment pressure by 20 to 30%, depending on the heat load, (iii) the effect of condensing fins is negligible for the proposed fin dimensions and material. However, by reducing the fin width, increasing their thickness, doubling their number, and using a higher conductive metal than the steel, it is expected that the containment pressure can be further reduced by 10% or more, (iv) the fins' dimensions and their number must be optimized via maximizing the difference or the ratio between the heat removed and pressure drop to get maximum heat flow rate

  20. Consequences of irreversibilities on optimal intertemporal CO2 emission policies under uncertainty

    This paper investigates how irreversibilities affect the optimal intertemporal accumulation of greenhouse gases in the atmosphere under uncertainty. More precisely, the evolution of the future temperature is assumed to follow an Ito-process with the drift provided by greenhouse gas emissions. This paper considers two different kinds of irreversibilities: of emissions (i.e., CO2 once dissolved into the air cannot be collected later) and of stopping. These issues are investigated first (in the tradition of the real option literature) as pure stopping problems and then allowing for a continuous choice of emissions. Implications for global warming are: an irreversible stopping of greenhouse gas emissions is never optimal in a continuous framework and yields in the real option framework a less conservationist stopping rule in which uncertainty increases the stopping threshold (i.e. works against conservation). (author)

  1. Generic uncertainty model for DETRA for environmental consequence analyses. Application and sample outputs

    Computer model DETRA applies a dynamic compartment modelling approach. The compartment structure of each considered application can be tailored individually. This flexible modelling method makes it possible that the transfer of radionuclides can be considered in various cases: aquatic environment and related food chains, terrestrial environment, food chains in general and food stuffs, body burden analyses of humans, etc. In the former study on this subject, modernization of the user interface of DETRA code was carried out. This new interface works in Windows environment and the usability of the code has been improved. The objective of this study has been to further develop and diversify the user interface so that also probabilistic uncertainty analyses can be performed by DETRA. The most common probability distributions are available: uniform, truncated Gaussian and triangular. The corresponding logarithmic distributions are also available. All input data related to a considered case can be varied, although this option is seldomly needed. The calculated output values can be selected as monitored values at certain simulation time points defined by the user. The results of a sensitivity run are immediately available after simulation as graphical presentations. These outcomes are distributions generated for varied parameters, density functions of monitored parameters and complementary cumulative density functions (CCDF). An application considered in connection with this work was the estimation of contamination of milk caused by radioactive deposition of Cs (10 kBq(Cs-137)/m2). The multi-sequence calculation model applied consisted of a pasture modelling part and a dormant season modelling part. These two sequences were linked periodically simulating the realistic practice of care taking of domestic animals in Finland. The most important parameters were varied in this exercise. The performed diversifying of the user interface of DETRA code seems to provide an easily

  2. A brief overview uncertainties in climate change projections and their consequences for impact assessment

    Tebaldi, C.

    2014-12-01

    Using as an entry-point a recent study that quantified the risk of global crop production slowdown due to anthropogenic warming in the next couple of decades, I will talk about approaches to characterizing uncertainties in future climate projections; I will highlight the hurdles and challenges in translating characterization into quantification; and I will offer some examples of methodologies in the literature. I hope to span, with this overview, the space of assumptions that I consider crucial to any formal analysis of climate projections and their effects on human or natural systems.

  3. Prenatal diagnostics of congenital malformations, the most efficient way to decrease genetic consequences of Chernobyl accident

    in the last 5 years about 500 pregnancies were terminated annually for genetic reasons. Over 100 pregnancies were terminated in Gomel region, which considerably reduced (by 1-3%) perinatal mortality, children's morbidity and disability. The number of children, born with the anomalies of the central nervous system, renal polycystosis and agenesis, omphalocele, reduction limb defects, is decreasing most considerably. The potentialities of prenatal diagnostics of CM are far from being used adequately in the Republic. With sufficient financing, present-day techniques allow prenatal diagnosing of 1000 cases instead of 600 diagnosed each year. The program will be productive, if prenatal biochemical screening and invasive prenatal procedures are financed regularly and interregional centres for prenatal diagnostics are created. These measures will not only reduce the proportion of children, born with congenital malformations, but increase the birth rate in Belarus, since the future mothers will not be scared to give birth to a malformed child, which is especially essential for the population exposed to radiation due to Chernobyl accident (authors)

  4. Including uncertainty in hazard analysis through fuzzy measures

    This paper presents a method for capturing the uncertainty expressed by an Hazard Analysis (HA) expert team when estimating the frequencies and consequences of accident sequences and provides a sound mathematical framework for propagating this uncertainty to the risk estimates for these accident sequences. The uncertainty is readily expressed as distributions that can visually aid the analyst in determining the extent and source of risk uncertainty in HA accident sequences. The results also can be expressed as single statistics of the distribution in a manner analogous to expressing a probabilistic distribution as a point-value statistic such as a mean or median. The study discussed here used data collected during the elicitation portion of an HA on a high-level waste transfer process to demonstrate the techniques for capturing uncertainty. These data came from observations of the uncertainty that HA team members expressed in assigning frequencies and consequences to accident sequences during an actual HA. This uncertainty was captured and manipulated using ideas from possibility theory. The result of this study is a practical method for displaying and assessing the uncertainty in the HA team estimates of the frequency and consequences for accident sequences. This uncertainty provides potentially valuable information about accident sequences that typically is lost in the HA process

  5. Results and tasks of the implementation of federal target programs aimed at overcoming the consequences of radiation accidents and catastrophes in the Russian Federation

    Major results are presented on the implementation of federal target programs on overcoming the consequences of the accident at the Chernobyl nuclear power plant, radiation accidents and incidents at the 'Mayak' Industrial Association, nuclear tests at the Semipalatinsk test site in the period of 1992-2000. The status of the standards and legislation regulating the activities aimed at population protection and rehabilitation of territories is analyzed. The current state of the problem is evaluated. The proposals are laid down for major directions of the state policy of the Russian Federation in overcoming the consequences of radiation accidents for the period until 2010, and the outlook for the efforts in the above domain and the above period is given. About 130 thousand square kilometers of the territories of 20 Russian Federation subjects with a population of around 4 million people were affected by accidents at nuclear fuel cycle sites/facilities, and nuclear and hydrogen weapons tests. The accidents entailed a host of grave radioecological, medical, demographic, and socio-economic consequences, exerted a significant unfavorable impact upon the socio-economic development of the affected territories. (author)

  6. Thyroid cancer in children living near Chernobyl. Expert panel report on the consequences of the Chernobyl accident

    In January 1992, the Radiation Protection Research Action formed a panel of thyroid experts in order to evaluate the current situation concerning reported increased rates of thyroid cancer in children living in the neighbourhood of Chernobyl, where the reactor accident occurred on April 26 1986 and resulted in widespread radioactive contamination over large areas of Belarus, Russia, Ukraine. Studies of the Atom Bomb survivors in Japan have revealed that the incidence of leukemia starts to increase some five years after exposure. For Chernobyl accident health consequences are now becoming evident. Thyroid cancer has already been observed in children. Iodine 131 was seen to pose a specific hazard because it is taken up by the body and concentrated in the thyroid gland. At a dose of 5 Gy to the childhood thyroid about 4000 thyroid cancers per 100000 children exposed can be anticipated. An essential component of the verification of this observation is the study of the pathology of the lesions, which derived from four cell types: follicular cells, C cells, lymphoid cells and connective tumor cells. All distant metastases are lung metastases. Measures to be considered for the prevention of the development of thyroid cancer in a radiation-exposed population include correction of iodine deficiency by iodine prophylaxis and suppression of TSH. There are three methods of diagnosis: ultrasound imaging, thyroid scanning, fine needle aspiration performed by skilled personnel. For the therapy total or near-total thyroidectomy is regarded as the treatment of choice. Radioactive iodine can be used to treat lymph node and distant metastases which take up iodine after a total thyroidectomy. Thyroid hormone replacement should be carried out with TSH suppressive doses of L-Thyroxine. 45 refs., 1 annexe

  7. The reactor accident in Fukushima Daiichi. The consequence of design deficiencies and inadequate safety engineering; Der Reaktorunfall in Fukushima Daiichi. Folge fehlerhafter Auslegung und unzureichender Sicherheitstechnik

    NONE

    2015-03-15

    The reactor accident in Fukushima Daiichi is discussed in the frame of design deficiencies and inadequate safety engineering. The progress of the accident as consequence of the earthquake and the tsunami is described. The radiological situation for the public is supposed to be blow the dose limit of 20 mSv/year. The WHO and UNSCEAR (United Nations Scientific Committee on the Effects of Atomic radiation) did not observe acute radiation injuries. The Japanese authorities have classified the accident to 7 of the INES scale. The German Atomforum e.V. considers the safety engineering of German NPPs to be superior to the Japanese situation due to higher emergency energy supply, extensive measures to reduce the hydrogen accumulation and mitigating measures for the accident management. German NPPS are considered highly robust as the EU stress tests have shown.

  8. Investigations on the safety of radioactive materials transport. Pt. 2. Modeling of the radiological consequences in the vicinity of an accident. Final report on the working package 2

    One aim of this project 3611R03300 was to analyse methods and procedures accord-ing to state-of-the-art technology concerning their applicability to assess the radiologi-cal consequences in the near vicinity of a transport accident. The analysis focusses on the dispersion models used for the airborne radionuclides released during an accident. In view of the large amount of simulations needed for a probabilistic assessment of the accident's radiological impact, simplified methods to calculate nuclide concentrations and deposition rates for the near vicinity were searched. Additionally, conservative fac-tors were determined to convert the results valid for 150 m distance to the accident, which was the shortest distance examined in the Transportstudie Konrad 2009, to the near vicinity (20 m distance).

  9. 30th and 29th anniversary of reactor accidents in A-1 nuclear power plant Jaslovske Bohunice - radioecological and radiobiological consequences

    In this paper authors present facts about construction, operation and reactor accidents in A-1 Nuclear Power Plant Jaslovske Bohunice, Slovakia. There was the reactor KS 150 (HWGCR) cooled with carbon dioxide and moderated with heavy water. A-1 NPP was commissioned on December 25, 1972. The first reactor accident happened on January 5, 1976 during fuel loading. Two persons of personal died by suffocation with carbon dioxide. This accident has been not evaluated according to the INES scale up to present time. The second serious accident in A-1 NPP occurred in February 22, 1977 also during fuel loading. This INES level 4 of reactor accident resulted in damaged fuel integrity with extensive corrosion damage of fuel cladding and release of radioactivity into the plant area. The A-1 NPP was consecutively shut down and is being decommissioned in the present time. Both reactor accidents are described in this paper. Some radioecological and radiobiological consequences of accidents and contamination of area of A-1 NPP as well as of Manivier canal and Dudvah River as result of flooding during the decommissioning are presented. (authors)

  10. Quantifying reactor safety margins: Application of code scaling, applicability, and uncertainty evaluation methodology to a large-break, loss-of-coolant accident

    The US Nuclear Regulatory Commission (NRC) has issued a revised rule for loss-of-coolant accident/emergency core cooling system (ECCS) analysis of light water reactors to allow the use of best-estimate computer codes in safety analysis as an option. A key feature of this option requires the licensee to quantify the uncertainty of the calculations and include that uncertainty when comparing the calculated results with acceptance limits provided in 10 CFR Part 50. To support the revised ECCS rule and illustrate its application, the NRC and its contractors and consultants have developed and demonstrated an uncertainty evaluation methodology called code scaling, applicability, and uncertainty (CSAU). The CSAU methodology and an example application described in this report demonstrate that uncertainties in complex phenomena can be quantified. The methodology is structured, traceable, and practical, as is needed in the regulatory arena. The methodology is systematic and comprehensive as it addresses and integrates the scenario, experiments, code, and plant to resolve questions concerned with: (a) code capability to scale-up processes from test facility to full-scale nuclear power plants; (b) code applicability to safety studies of a postulated accident scenario in a specified nuclear power plant; and (c) quantifying uncertainties of calculated results. 127 refs., 55 figs., 40 tabs

  11. Radioecological consequences of Chernobyl accident for Lake ecosystems within 10 km exclusion zone

    During 1997-2005 we studied distribution and dynamics of 90Sr, 137Cs, 238Pu, 239+240Pu and 241Am in the main components of the aquatic ecosystems within exclusion zone, defined as a roughly circular area of 30-km radius around the destroyed unit of the Chernobyl NPP. Our special attention was given to bottom sediments, water, seston, higher aquatic plants, molluscs and fish of lake ecosystems within inner (10-km) exclusion zone: Azbuchin Lake, Dalekoye Lake and Glubokoye Lake. The data analysis has shown that about 98-99% of 137Cs and more than 99% of transuranic elements of the total radionuclide content has deposited in the bottom sediments. The content of 90Sr in sediments of lakes, due to higher solubility, amounts to 89-95%. About 2-10% of radionuclides concentrated in water and only about 1% - in biota. In this percent a prevailing value for different radionuclides has the macro benthos species (especially bivalve molluscs) and higher aquatic plants. The average specific activity of radionuclides in fish tissue more than in 100 times exceeds a maximum permissible level for fish production in Ukraine. The absorbed dose rate for hydrobionts, living within littoral zone of the researched lakes, due to external irradiation and radionuclides incorporated in tissue was in a range from 0.2 to 3.4 Gy year-1. The highest value was found for hydrobionts from lakes within embankment territory on left-bank flood plain of the Pripyat River with high density of radionuclide contamination (Dalekoye Lake and Glubokoye Lake). The numerous effects of irradiation on hydrobionts within the exclusion zone are revealed. Some of these effects required for the short period of time for their formation, however it is supposed that an increasing importance will be got by the remote consequences - genetic damages induced by a long-term irradiation. The molluscs embryos from Dalekoye-1 Lake and Glubokoye Lake were characterised by the highest rate of chromosome aberration - about 20

  12. Consequences of Chernobyl accident for Poland: Retrospective assessment after 10 years; Skutki katastrofy w Czarnobylu dla Polski: Ocena retrospektywna po 10 latach

    Jaskowski, J. [Akademia Medyczna, Gdansk (Poland)

    1996-12-31

    The regional contamination in Poland after Chernobyl accident has been presented. On this base the biological and medical consequences have been discussed. The neonatal mortality as well as cancer frequency for selected regional population in Poland have been analysed during the last decade. 10 figs, 20 tabs.

  13. Risk management & organizational uncertainty implications for the assessment of high consequence organizations

    Bennett, C.T.

    1995-02-23

    Post hoc analyses have demonstrated clearly that macro-system, organizational processes have played important roles in such major catastrophes as Three Mile Island, Bhopal, Exxon Valdez, Chernobyl, and Piper Alpha. How can managers of such high-consequence organizations as nuclear power plants and nuclear explosives handling facilities be sure that similar macro-system processes are not operating in their plants? To date, macro-system effects have not been integrated into risk assessments. Part of the reason for not using macro-system analyses to assess risk may be the impression that standard organizational measurement tools do not provide hard data that can be managed effectively. In this paper, I argue that organizational dimensions, like those in ISO 9000, can be quantified and integrated into standard risk assessments.

  14. Accidents - Chernobyl accident

    This file is devoted to the Chernobyl accident. It is divided in four parts. The first part concerns the accident itself and its technical management. The second part is relative to the radiation doses and the different contaminations. The third part reports the sanitary effects, the determinists ones and the stochastic ones. The fourth and last part relates the consequences for the other European countries with the case of France. Through the different parts a point is tackled with the measures taken after the accident by the other countries to manage an accident, the cooperation between the different countries and the groups of research and studies about the reactors safety, and also with the international medical cooperation, specially for the children, everything in relation with the Chernobyl accident. (N.C.)

  15. Optimisation of information influences on problems of consequences of Chernobyl accident and quantitative criteria for estimation of information actions

    Consequences of Chernobyl NPP accident still very important for Belarus. About 2 million Byelorussians live in the districts polluted by Chernobyl radionuclides. Modern approaches to the decision of after Chernobyl problems in Belarus assume more active use of information and educational actions to grow up a new radiological culture. It will allow to reduce internal doze of radiation without spending a lot of money and other resources. Experience of information work with the population affected by Chernobyl since 1986 till 2004 has shown, that information and educational influences not always reach the final aim - application of received knowledge on radiating safety in practice and changing the style of life. If we take into account limited funds and facilities, we should optimize information work. The optimization can be achieved on the basis of quantitative estimations of information actions effectiveness. It is possible to use two parameters for this quantitative estimations: 1) increase in knowledge of the population and experts on the radiating safety, calculated by new method based on applied theory of the information (Mathematical Theory of Communication) by Claude E. Shannon and 2) reduction of internal doze of radiation, calculated on the basis of measurements on human irradiation counter (HIC) before and after an information or educational influence. (author)

  16. Quality assurance and verification of the MACCS [MELCOR Accident Consequence Code System] code, Version 1.5

    An independent quality assurance (QA) and verification of Version 1.5 of the MELCOR Accident Consequence Code System (MACCS) was performed. The QA and verification involved examination of the code and associated documentation for consistent and correct implementation of the models in an error-free FORTRAN computer code. The QA and verification was not intended to determine either the adequacy or appropriateness of the models that are used MACCS 1.5. The reviews uncovered errors which were fixed by the SNL MACCS code development staff prior to the release of MACCS 1.5. Some difficulties related to documentation improvement and code restructuring are also presented. The QA and verification process concluded that Version 1.5 of the MACCS code, within the scope and limitations process concluded that Version 1.5 of the MACCS code, within the scope and limitations of the models implemented in the code is essentially error free and ready for widespread use. 15 refs., 11 tabs

  17. Review of psychological consequences of nuclear accidents and empirical study on peoples reactions to radiation protection activities in an imagined situation.; Katsaus ydinonnettomuuksien psykologisiin seurauksiin sekae empiirinen tutkimus saeteilysuojelutoimenpiteiden vaikutuksista kaeyttaeytymiseen kuvitteelisessa tilanteessa

    Haukkala, A.; Eraenen, L. [Helsinki Univ. (Finland). Dept. of Social Psychology

    1994-10-01

    The report consist of two parts: a review of studies on psychological consequences of nuclear and radiation accidents in population and an empirical study of peoples reactions to protection actions in an event of hypothetical accident. Review is based on research results from two nuclear reactor accidents (Three Mile Island 1979, Chernobyl 1986) and a radiation accident in Goiania, Brazil 1987. (53 refs, 2 figs.,7 tabs.).

  18. The Chernobyl accident 20 years on: an assessment of the health consequences and the international response O acidente de Chernobyl 20 anos depois: avaliação das conseqüências e resposta internacional

    Keith Baverstock; Dillwyn Williams

    2007-01-01

    Twenty years after the Chernobyl accident the WHO and the International Atomic Energy Authority issued a reassuring statement about the consequences. Our objectives in this study were to evaluate the health impact of the Chernobyl accident, assess the international response to the accident, and consider how to improve responses to future accidents. So far, radiation to the thyroid from radioisotopes of iodine has caused several thousand cases of thyroid cancer but very few deaths; exposed chi...

  19. An Evaluation of the Role that Traffic Culture Plays in Reducing Consequences of Accidents and Promoting Social Security and Order

    Nasser Pourmoallem; Seyed Ehsan Jafari Nasab

    2013-01-01

    IntroductionAccidents and traffic security have become serious issues in our country, to the extent that most of the people and authorities are severely concerned about them. On the other hand, research shows that human factor has the most important role in the occurrence of accidents. According to the records, only %1 of all accidents in Iran are resulted from "vehicle malfunction" and “immunodeficiency of the roads”; while other events, directly or indirectly, are caused by human wrong oper...

  20. The analysis outlining the occurrence and consequences of accidents in the work environment of the firefighters employed by the State Fire Service in Poland in 2008–2013

    Agata Pawlak

    2016-02-01

    Full Text Available Background: Due to the specifics of their work and to being exposed to a wide range of hazards, firefighters working for the State Fire Service (SFS face the risk of work-related accidents more often than members of other occupational groups. The aim of this paper is to analyze the occurrence and consequences of accidents in the work environment of the SFS officers in Poland between the years 2008–2013. Material and Methods: The material analyzed is based on aggregate data collected by the Headquarters of the State Fire Service. Figures regarding accidents in the period between 1 January 2008 and 31 December 2013 show that 8518 workrelated accidents occurred in that period and 8635 people were injured. Results: The data shows that neither the number of accidents nor their frequency indicator underwent any significant fluctuations over the 6 years under consideration. The group that is most exposed to accidents on duty in the profession includes active firefighters serving in rescue and fire extinguishment divisions. According to the data, the greatest number of trauma incidents in the SFS between the years 2008–2013 occurred during sporting activities. The predominant cause of these was inappropriate behavior or the lack of proper care. The most frequent injuries sustained during the accidents were broken or fractured bones and sprained joints. Conclusions: Accidents on duty occur significantly more often when firefighters are at their stations, during sporting classes, exercises or maneuvers, than in the course of actual rescue operations. The firefighters of the State Fire Services are insufficiently prepared for their sporting activities. Med Pr 2016;67(1:1–9

  1. The Chernobyl accident 20 years on: an assessment of the health consequences and the international response O acidente de Chernobyl 20 anos depois: avaliação das conseqüências e resposta internacional

    Keith Baverstock

    2007-06-01

    Full Text Available Twenty years after the Chernobyl accident the WHO and the International Atomic Energy Authority issued a reassuring statement about the consequences. Our objectives in this study were to evaluate the health impact of the Chernobyl accident, assess the international response to the accident, and consider how to improve responses to future accidents. So far, radiation to the thyroid from radioisotopes of iodine has caused several thousand cases of thyroid cancer but very few deaths; exposed children were most susceptible. The focus on thyroid cancer has diverted attention from possible nonthyroid effects. The international response to the accident was inadequate and uncoordinated, and has been unjustifiably reassuring. Accurate assessment in future health effects is not currently possible in the light of dose uncertainties, current debates over radiation actions, and the lessons from the late consequences of atomic bomb exposure. Because of the uncertainties from and the consequences of the accident, it is essential that investigations of its effects should be broadened and supported for the long term. The United Nations should initiate an independent review of the actions and assignments of the agencies concerned, with recommendations for dealing with future international-scale accidents. These should involve independent scientists and ensure cooperation rather than rivalry.Vinte anos após o acidente de Chernobyl ocorrido em 1986, a OMS e a Autoridade Internacional sobre Energia Atômica lançaram um relatório sobre as conseqüências desse desastre. Nosso objetivo neste estudo é avaliar o impacto de tal acidente sobre a saúde e a reação internacional sobre o ocorrido, além de considerar se é possível melhorar as respostas em futuros desastres. Observamos que a radiação sobre a tireóide, proveniente de radioisótopos de iodo, causou milhares de casos de câncer, mas poucas mortes; as crianças expostas foram as mais suscetíveis. O

  2. Management of radioactive waste during the initial period of eliminating the consequences of the Chornobyl accident. Review and analysis

    This review discusses basic sources of radioactive waste (RAW) formation during the Chornobyl accident, processes of RAW formation, and describes the relevant experience of RAW collection and disposal. Not all sources and materials were available for the research, but the author endeavored to provide the most comprehensive presentation of all the aspects of RAW management during elimination of the Chornobyl accident

  3. 2. International conference. Radiobiological consequences of nuclear accidents; Russian-Norwegian Satellite Symposium on nuclear accidents, radioecology and health. Abstracts. Part 2

    Materials on radiobiological effect of ionizing radiation under emergency situations are presented. The radiation contamination of environmental media after the Chernobyl NPP accident (ground, earth and water ecological systems), effect of external and internal irradiation on the inhabitants of the region are estimated. Time characteristic of radiation risk of originating tumors and genetic injuries is given

  4. Using accident management to address phenomenological uncertainties related to lower plenum debris bed chemistry and mixing during in-vessel retention (IVR) of molten core debris in the AP1000 passive plant

    In-vessel retention (IVR) of core debris via external reactor vessel cooling is an important severe accident management strategy that is inherent in the AP1000 passive nuclear power plant. Uncertainties in molten debris bed chemistry and mixing behavior in the lower plenum of a RPV (reactor pressure vessel), at the extreme bounding limits, have been suggested to potentially result in lower plenum debris bed configurations that may challenge vessel integrity during IVR. To resolve epistemic uncertainties related to severe accident phenomena, the uncertainties are addressed via engineered severe accident management solutions that are shown to be reliable using a probabilistic framework to quantify success. Vessel failure probability and large release frequency in the AP1000 plant design are demonstrated to be as low as reasonably practicable (ALARP), and the IVR strategy is demonstrated to provide a robust approach to severe accident management in the AP1000 plant, capable of addressing postulated uncertainties and concerns

  5. An experience of information support of the Russian federal programs of the overcoming of consequences of the accident at the Chernobyl NPP

    Since 1992, by a number of paragraphs of the federal programs on overcoming consequences of accident on Chernobyl NPP, the measures on informational-analytic support of the federal programs were provided. Within the framework of this activity for the solution of various aspects of Chernobyl's problem central bank of generalized data and numerous information systems were created. In the report the brief description of some of them is presented. In particular the databank on radioactive situation includes the information on 12 thousand settlements of Russia which have been exposed to radioactive contamination as a result of the accident.The medico-demographic section of a databank includes information on death rate for the reasons for all subjects of Russian Federation since 1982 till the present time. The developed information systems are available to all participants of work on overcoming of consequences of the accident. There are given the examples of integral estimates in short- and long-term forecasts of development of a situation in territories suffered by the accident at the Chernobyl NPP. (author)

  6. An uncertainty analysis of the hydrogen source term for a station blackout accident in Sequoyah using MELCOR 1.8.5

    Gauntt, Randall O.; Bixler, Nathan E.; Wagner, Kenneth Charles.

    2014-03-01

    A methodology for using the MELCOR code with the Latin Hypercube Sampling method was developed to estimate uncertainty in various predicted quantities such as hydrogen generation or release of fission products under severe accident conditions. In this case, the emphasis was on estimating the range of hydrogen sources in station blackout conditions in the Sequoyah Ice Condenser plant, taking into account uncertainties in the modeled physics known to affect hydrogen generation. The method uses user-specified likelihood distributions for uncertain model parameters, which may include uncertainties of a stochastic nature, to produce a collection of code calculations, or realizations, characterizing the range of possible outcomes. Forty MELCOR code realizations of Sequoyah were conducted that included 10 uncertain parameters, producing a range of in-vessel hydrogen quantities. The range of total hydrogen produced was approximately 583kg 131kg. Sensitivity analyses revealed expected trends with respected to the parameters of greatest importance, however, considerable scatter in results when plotted against any of the uncertain parameters was observed, with no parameter manifesting dominant effects on hydrogen generation. It is concluded that, with respect to the physics parameters investigated, in order to further reduce predicted hydrogen uncertainty, it would be necessary to reduce all physics parameter uncertainties similarly, bearing in mind that some parameters are inherently uncertain within a range. It is suspected that some residual uncertainty associated with modeling complex, coupled and synergistic phenomena, is an inherent aspect of complex systems and cannot be reduced to point value estimates. The probabilistic analyses such as the one demonstrated in this work are important to properly characterize response of complex systems such as severe accident progression in nuclear power plants.

  7. Administrative circular No.14 (Rev. 3) – Protection of members of the personnel against the financial consequences of illness, accident and incapacity for work

    2013-01-01

    Administrative Circular No. 14 (Rev. 3) entitled “Protection of members the personnel against the financial consequences of illness, accident and incapacity for work”, approved by the Director-General following discussion at the Standing Concertation Committee meeting of 19 April 2012 and entering into force on 1 January 2013, is available on the intranet site of the Human Resources Department.   This circular is applicable to all members of the personnel. It cancels and replaces Administrative Circular No. 14 (Rev. 2) entitled “Protection of members of the personnel against the financial consequences of illness, accident and disability” from July 2006. The circular was revised in order to improve the procedure before the Joint Advisory Rehabilitation and Disability Board (JARDB) and the management of long-term sick leave through a multidisciplinary approach launched upstream. The aim of this approach is to allow staff/fellows c...

  8. The environmental consequences of a major accident at a nuclear power plant: rehabilitation of soils and land

    The objectives of the RESSAC project are to study the technique, of and their applications to the intervention to the contaminated zones induced by a nuclear power plant accident, in order to rehabilitate the terrain surface for normal use. The short-term and long-term impacts of the accident are evaluated, and the detection and transport of radionuclides in the soil and the vegetation are investigated. (R.P.) 6 refs

  9. Consequences of the Chernobyl accident in Russia: search for effects of radiation exposure in utero using psychometric tests

    Psychometric indicators for mental development of children in towns distinguished by radioactive contamination resulting from the Chernobyl accident are studied. Using some radiological information obtained after the Chernobyl accident, values of expected intelligence quotient (IQ) reduction have been assessed as a result of brain exposure in utero due to various components of dose. Comparing the results of examinations in Novozybkov, Klintsy and Obninsk, no confident evidence has been obtained that radiation exposure of the developing brain exerts influence on indicators for mental development

  10. Source term uncertainties for the Seabrook station probabilistic risk assessment

    Accident source terms are defined as a set of release categories that define the time and quantity of radionuclides released for different containment failure modes and groups of accident sequences. Best estimates of these source terms are characterized by very large uncertainties. A probabilistic risk assessment (PRA) aims to determine realistic consequences. Estimating source term uncertainties is therefore as important as estimating the source terms themselves. A systematic analysis of source term uncertainties was performed for the Seabrook PRA. Uncertainties were quantified due to in-vessel retention, ex-vessel retention, different accident sequences, accident progression phenomena, containment failure time, containment failure modes, and leak path attenuation. The cumulative effect of all sources of uncertainties resulted in a difference between best estimate release fractions and the 99% confidence level of a factor of 10 to 100. The CORRAL predicted release fractions are found to be upper bounds with a 99% confidence level or higher

  11. Source term uncertainties for the seabrook station probabilistic risk assessment

    Accident source terms are defined as a set of release categories that define the time and quantity of radionuclides released for different containment failure modes and groups of accident sequences. Best estimates of these source terms are characterized by very large uncertainties. A probabilistic risk assessment (PRA) aims to determine realistic consequences. Estimating source term uncertainties is therefore as important as estimating the source terms themselves. A systematic analysis of source term uncertainties was performed for the Seabrook PRA. Uncertainties were quantified due to in-vessel retention, ex-vessel retention, different accident sequences, accident progression phenomena, containment failure time, containment failure modes, and leak path attenuation. The cumulative effect of all sources of uncertainties resulted in a difference between best estimate release fractions and the 99% confidence level of a factor of 10 to 100. The CORRAL predicted release fractions are found to be upper bounds with a 99% confidence level or higher

  12. Code comparison with MAAP 3.0 and March 3 (-STCP) for Nordic BWR and PWR plants to evaluate uncertainties in severe accident phenomena

    This study has been carried out within the framework of the Nordic NKA-AKTI-130-project whose participants are from Denmark, Finland and Sweden. The study is financed partly by the Nordic liaison committee for atomic energy and partly by national organisations. The goals of the study have been to achieve a common Nordic understanding of the capabilities of the severe accident codes MAAP 3.0 /1, 2/ and March 3-STCP /3/ and to evaluate uncertainties in severe accident phenomena by performing benchmark calculations and related sensitivity analyses for the existing Nordic power plants. The MAAP 3.0 code, which is an integrated thermal hydraulic and aerosol code, has been the main analysis tool in severe accident analyses in Sweden and Finland. Danish organisations have used the Source Term Code Package system (Mod 1.0) which is composed of several separate codes such as March 3, TRAPMELT etc. When plant specific design features are analyzed, a sensitivity type of study with a code system like MAAP 3.0 is an efficient tool. Experimental data for validation of code systems modelling the complex phenomena involved in severe accidents are, however, limited. It is in this situation valuable to compare models and results for two code systems developed by different organizations

  13. Report on the consequences of Chernobylsk accident in France Minister missions from the 25. february to 6. august 2002

    Actually, we have not any map that gives reliable quantitative data of Chernobylsk accident fallout on soils. The maps proposed for these deposits give order of magnitude; they find east-west gradient conform to the origin of the accident and confirm the importance of the rain. But the quantitative value is only an approximation where the precision is not known (error interval). It does not allow to know the radiation doses to the thyroid because the food contamination does not increase like the soils contamination. It could be possible to improve the models but the scientific council of I.R.S.N. proposes to realize a periodic ground state of soils contamination in cesium. It would be a better step of a more reliable mapping of Chernobylsk accident fallout. (N.C.)

  14. RaCon: a software tool serving to predict radiological consequences of various types of accident in support of emergency management and radiation monitoring management

    The RaCon software system, developed by the Nuclear Research Institute Rez, is described and its application when addressing various tasks in the domain of radiation accidents and nuclear safety (accidents at nuclear facilities, transport of radioactive material, terrorist attacks) are outlined. RaCon is intended for the prediction and evaluation of radiological consequences to population and rescue teams and for optimization of monitoring actions. The system provides support to emergency management when evaluating and devising actions to mitigate the consequences of radiation accidents. The deployment of RaCon within the system of radiation monitoring by mobile emergency teams or remote controlled UAV is an important application. Based on a prediction of the radiological situation, RaCon facilitates decision-making and control of the radiation monitoring system, and in turn, refines the prediction based on observed values. Furthermore, the system can perform simulations of evacuation patterns at the Dukovany NPP and at schools in the vicinity of the power plant and can provide support to emergency management should any such situation arise. (orig.)

  15. Investigation of loss of coolant accidents in pressurized water reactors using the ''Dynamic Best-Estimate Safety Analysis'' (DYBESA) method for considering of uncertainties in TRACE

    Sporn, Michael; Hurtado, Antonio [Technische Univ. Dresden (Germany)

    2016-02-15

    Loss of coolant accident must take uncertainties with potentially strong effects on the accident sequence prediction into account. For example, uncertainties in computational model input parameters resulting from varying geometry and material data due to manufacturing tolerances or unavailable measurements should be considered. The uncertainties of physical models used by the software program are also significant. In this paper, use of the ''Dynamic Best-Estimate Safety Analysis'' (DYBESA) method to quantify the uncertainties in the TRACE thermal-hydraulic program is demonstrated. For demonstration purposes loss of coolant accidents with breaks of various types and sizes in a DN 700 reactor coolant pipe are used as an example Application.

  16. Investigation of loss of coolant accidents in pressurized water reactors using the ''Dynamic Best-Estimate Safety Analysis'' (DYBESA) method for considering of uncertainties in TRACE

    Loss of coolant accident must take uncertainties with potentially strong effects on the accident sequence prediction into account. For example, uncertainties in computational model input parameters resulting from varying geometry and material data due to manufacturing tolerances or unavailable measurements should be considered. The uncertainties of physical models used by the software program are also significant. In this paper, use of the ''Dynamic Best-Estimate Safety Analysis'' (DYBESA) method to quantify the uncertainties in the TRACE thermal-hydraulic program is demonstrated. For demonstration purposes loss of coolant accidents with breaks of various types and sizes in a DN 700 reactor coolant pipe are used as an example Application.

  17. Uncertainty and sensitivity analysis for a nuclear power plant Large Break Loss of Coolant Accident (LB-LOCA) in the context of OECD BEMUSE programme

    The second comparative exercise performed as part of BEMUSE (Best Estimate Methods - Uncertainty and Sensitivity Evaluation) Programme, was devoted to Nuclear Power Plant (NPP) application. The BEMUSE programme has been promoted by the Working Group on Analysis and Management of Accidents (WGAMA) and endorsed by the Committee on the Safety of Nuclear Installations (CSNI). The programme was divided into two main steps. The first step was to perform an uncertainty and sensitivity analysis related to the LOFT L2-5 test, and the second step was to perform the same analysis for a Nuclear Power Plant Large Break Loss of Coolant Accident (LB-LOCA). The second step, also known as Phases IV and V, started in May 2006 and was finished in September 2009. Phase IV of BEMUSE Program is connected with previous Phase II, being a necessary step for an uncertainty analysis: the simulation of the reference scenario and sensitivity analysis. The selected plant was Zion 1 NPP, a 4 loop PWR unit. Thirteen participants coming from ten different countries have taken part in the Phase IV of the program. Phase V main objective was to obtain uncertainty bands for the maximum cladding temperature (time trend), upper plenum pressure (time trend), maximum peak cladding temperature (scalar), 1st peak cladding temperature (scalar), 2nd peak cladding temperature (scalar), time of accumulator injection (scalar), time of complete core quenching (scalar). Fourteen groups from twelve organizations and ten countries have participated in BEMUSE Phase V. Both Phases IV and V compared procedures with experience gained in the previous step of the programme. (author)

  18. Non-radiological consequences to the aquatic biota and fisheries of the Susquehanna River from the 1979 accident at Three Mile Island Nuclear Station

    The non-radiological consequences to the aquatic biota and fishes of the Susquehanna River from the March 28, 1979 accident at Three Mile Island Nuclear Station were assessed through the post-accident period of July 1979. Thermal and chemical discharges during the period did not exceed required effluent limitations. Several million gallons of treated industrial waste effluents were released into the river which were not of unusual volumes compared with normal operation and were a very small proportion of the seasonally high river flows. The extent and relative location of the effluent plume were defined and the fisheries known to have been under its immediate influence were identified, including rough, forage, and predator/sport fishery species

  19. Search of the Russian scientific literature for the descriptions of the medical consequences of the Kyshtym accident

    Parker, F.L.

    1983-03-01

    This report describes a study concerning the nuclear waste accident at Kyshtym in the Soviet Urals in 1958. Soviet medical literature, interviews with potentially knowledgeable people, and the Samizdat Writing (underground documents smuggled to the West and/or surreptitiously circulated in the Soviet Union), were studied to attempt to determine what injuries or deaths, if any, occurred as a result of the event. All of the cases of radiation exposure discussed in the various literature searched seemed to be typical occupational or therapy overdoses. No allusion to the massive numbers reportedly irradiated in the accident appears in the literature searched. Evidently, these data are classified and not discussed in the open literature. This study also resulted in a modification of our understanding of the accident's cause; i.e., perhaps there was no single cause. At present, the best supposition is that there were many releases of wastes to the river system over time, plus an explosion in the fuel reprocessing plant, and that would help to explain the widespread distribution of nuclides. The lack of short-half-lived nuclides relative to long-lived ones can also be explained by the release over an extended period and the time between the accident and the beginning of the studies.

  20. TRACE - a time-dependent and realistic accident consequence evaluation module for use in emergency response planning

    Following the identification of an off-normal condition at nuclear power plant, the plant operators have one over-riding responsibility: protection of the offsite population. In discharging this responsibility, the operators utilize a set of emergency operating procdedures. A. Immediately following the identification of the off-normal condition, the operators primary actions are focused on establishing a safe, stable shutdown condition for the reactor. B. The plant condition is categorized according to the perceived severity of the event based on a broad overview of the plant conditions, and the information is transmitted to appropriate governmental authorities. C. Estimations of potential environmental releases of radioactivity, based on design basis accident results, are performed and transmitted to the governmental authorities. The TRACE package was developed to provide the operators with the tools to make realistic predictions of the range of possible releases of radioactivity to the environment during all phases of an off-normal condition, including severe accident situations. The TRACE package provides a means to project, during the early stages of an accident, the potential range of possible fission product releases on a realistic and time-dependent basis. The TRACE package also provides a means to update previous evaluations of the potential range of radioactivity releases as plant conditions change or a new information (on accident sequence or plant parameters) becomes available. (orig./HSCH)

  1. Medical consequences for children population of survivors after the accident at the Chernobyl nuclear power plant (12 years later)

    Chernobyl NPP accident is recognized as the global disaster. Wide amount of population including children was involved. According to the direct measurements results from 1986 the 40% of children population received thyroid irradiation doses from 0.3 to 2.0 Gy and 10% of them - over 2 Gy respectively. Cesium incorporation value calculated per irradiation dose not exceeded 0.5 rem in 97% of kids. Children examination was organized in 2 steps. Within 1. one various transient reactions of nervous system, skin, mucosa, blood formula were revealed. Within 2. one the complete medical examinations were carried out both with dosimetric control. ChNPP accident poly-factor nature was fixed. Wide amount of somatic pathology not related to radiation exposure dose was registered. 12 years after the accident as the result of wide-scale epidemiological study was found out that children population had been exposed to both acute (evacuated persons) and long-term chronic (contaminated territories residents) effect of radiation factor. The main health risk for children involved in nuclear disaster zone is connected with non-oncological blood and haemopoietic organs diseases, digestive system pathology and mental disorders. Parameters excess was revealed in group of persons with higher collective dose accumulated for 10-12 years. Thyroid cancer incidence rate growth is recognized as the radioinduced effect. 12 years after the accident is obvious that 'health detriment' for children population of ChNPP accident survivors is expressed in additional number of endocrine system diseases cases - 24%, blood and haemopoietic organs - 33%, digestive system - 24%, mental disorders - 52% respectively. (authors)

  2. Environmental consequences of the Chernobyl accident and their remediation: Twenty years of experience. Report of the UN Chernobyl Forum Expert Group 'Environment' (EGE). Working material

    The purpose of this report is to provide an up-to-date evaluation of the environmental effects of the 26 April 1986 accident at the Chernobyl Nuclear Power Plant. Even though it is now nearly 20 years after the accident and substantial monies have been spent on such evaluations, there are still many conflicting reports and rumours. This joint report has been developed with the full cooperation of the United Nations (UN) family of relevant organisations and with political representatives from the three more affected countries: Ukraine, Belarus, and the Russian Federation. In addition, recognised scientific experts from the three countries and additional international experts provided the basis for the preparation of reports for review by the actual members of the Chernobyl Forum. The - Chernobyl Forum - is a high-level political forum whose suggestion for existence was initiated by the International Atomic Energy Agency (IAEA) in cooperation with the Food and Agriculture Organisation (FAO), the United Nations Office for Coordination of Humanitarian Affairs (OCHA), the United Nations Development Programme (UNDP), the United Nations Environment Programme (UNEP), the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), the World Health Organisation (WHO), and the World Bank, as well as the competent authorities of Belarus, the Russian Federation, and Ukraine. The organisational meeting of the Chernobyl Forum was held on 3-5 February 2003, at which time the decision was reached to establish the Forum as an ongoing entity of the above named organisations. Thus, the organisational meeting of the Forum decided to establish the Chernobyl Forum as a series of managerial, expert and public meetings in order to generate authoritative consensual statements on the health effects attributable to radiation exposure arising from the accident and the environmental consequences induced by the released radioactive materials, to provide advice on

  3. A real-time, dynamic early-warning model based on uncertainty analysis and risk assessment for sudden water pollution accidents.

    Hou, Dibo; Ge, Xiaofan; Huang, Pingjie; Zhang, Guangxin; Loáiciga, Hugo

    2014-01-01

    A real-time, dynamic, early-warning model (EP-risk model) is proposed to cope with sudden water quality pollution accidents affecting downstream areas with raw-water intakes (denoted as EPs). The EP-risk model outputs the risk level of water pollution at the EP by calculating the likelihood of pollution and evaluating the impact of pollution. A generalized form of the EP-risk model for river pollution accidents based on Monte Carlo simulation, the analytic hierarchy process (AHP) method, and the risk matrix method is proposed. The likelihood of water pollution at the EP is calculated by the Monte Carlo method, which is used for uncertainty analysis of pollutants' transport in rivers. The impact of water pollution at the EP is evaluated by expert knowledge and the results of Monte Carlo simulation based on the analytic hierarchy process. The final risk level of water pollution at the EP is determined by the risk matrix method. A case study of the proposed method is illustrated with a phenol spill accident in China. PMID:24781332

  4. Twenty years of the Chernobyl accident: Results and problems in eliminating its consequences in Russia 1986-2006. Russian national report

    Twenty years after the Chernobyl accident, above 1.5 million people in 14 subjects of the Russian Federation continue to live in the area of radioactive contamination. More than 180,000 of the Russians were affected by radiation, when participating in elimination of the accident and its consequences. Since the first days of the accident, the public health service faced a task to develop and implement the measures on minimization of medical effects of the accident and public provision with medical assistance, including the employees of the nuclear power plant and the participants in mitigation of the accident. The health of the liquidators and the public living in the contaminated areas is the most socially significant issue being solved in the process of elimination of the Chernobyl consequences. Radiological effects have been the focus of attention for the overall 20-year period. The radiation protection system was based on performance of the two conditions, namely: absolute prevention of acute (deterministic) effects and reduction in the risk of remote (stochastic) effects to acceptable (justified) levels. As early as in 1986, a decision was made to create the unified system of medical observation for the individuals affected by radiation as a result of the Chernobyl accident. The Russian State Medical and Dosimetry Register (RSMDR) was established on the basis of the Medical Radiological Research Center of the Russian Academy of Medical Sciences. The two most suffered public groups were defined as a result of research activity of the Register. These are the children (at the moment of the accident) living in the highly contaminated areas and the liquidators who have obtained the exposure dose above 150 mGy. According to the Register's data, 122 cases (54%) out of 226 thyroid cancers revealed during the years 1991-2003 among the children (at the moment of the Chernobyl catastrophe) from the Bryansk region can be considered as radiation-stipulated. Hygienic

  5. Cooperative research at JAERI on the consequences of the Chernobyl accident. 1. Study on the measurements and evaluation of environmental external exposure after the nuclear accident

    Measurement data obtained from 1992 mainly in 30 km distant areas from the accident reactor were analyzed and evaluated. On-site study included the radiation survey studies of wide range of areas with the spherical NaI(Tl) detector carried on the car and helicopter, studies on the accumulated dose in inhabitants and dose rate distribution of their residential settlements with the glass dosimeter and portable gamma dose-rate meter, experimental studies on the shielding effect of houses by simulation and studies on the characterization of environmental γ-ray field. These studies brought about developments of the method for rapid radiation survey in wide range of contaminated areas, of the evaluation method for estimated external exposure dose in residents, of the Monte Carlo arrangement method for evaluation of γ-ray doses and of analytical method for contaminated areas. Data were provided to organizations for measures of Ukraine and Belarus and would be also useful for possible urgent matters in future. (K.H.)

  6. Radiation accidents in the former Soviet Union: Medical consequences and experience in the application of radiation protection measures

    The Institute of Biophysics of the Russian Federation is a scientific center which has extensive archives containing scientific studies and information on radiation safety problems and occurrences since the early days of nuclear science and research and nuclear weapons tests in the Soviet Union. Some of this classified, top secret material has recently been published by Prof. L.A. Iljin in a renowned Russian scientific journal in the form of a review of radiation accidents in the Soviet Union, general medical reports, case reports, and the effects of nuclear weapons tests. He also added his own expert view of the accidents and their effects, and his conclusions relating to public health effects and required radiation protection policy. The article in this issue of Strahlenschutz Praxis is a German translation of excerpts from the original journal article. (orig./CB)

  7. Metabolic syndrome X as a clinical outcome of hormonal changes on the liquidators of the Chernobyl accident consequences (the problem analysis)

    An analysis of hormonal changes in the liquidators of the Chernobyl accident consequences, which promote the metabolic syndrome X development, was carried out on the base of clinical and experimental data. The system insulin-glucose, the mechanisms of insulinresistance and gyperinslinemia forming, the pathogenetical role of hyperinsulinemia interaction with others hormomes, some aspects of hormone - receptor interaction, an interconnection of hyperinsulinemia and vascular pathology, peculiarities of radiobiological stress as a non-classic adaptive reaction, which frequently resulting with a pathology, were discussed in the article

  8. Long-term therapy for polymorphic mental disorders in liquidators of the consequences of the accident at the Chernobyl nuclear power plant

    V. N. Krasnov

    2012-01-01

    Full Text Available The paper gives the results of a long-term comparative therapeutic study of a large cohort of more than 500 liquidators of the consequences of the accident at the Chernobyl nuclear power plant in 1986. The patients were followed up (and periodically treated at hospital 5 years or more, usually 10—15 years. The study confirmed mainly the cerebrovascular nature of disorders following the pattern seen in moderate psychoorganic syndrome. Therapy with cerebroprotective agents having vascular vegetotropic properties could yield certain therapeutic results and, to some extent, preserve social functioning capacity in these patients.

  9. Updated action plan for the implementation of measures as a consequence of the Fukushima reactor accident; Fortgeschriebener Aktionsplan zur Umsetzung von Massnahmen nach dem Reaktorunfall in Fukushima

    NONE

    2016-03-15

    The updated German action plan for the implementation of measures as a consequence of the Fukushima reactor accident covers the following issues: decision on the future utilization of nuclear energy in Germany; national frame for security checks, inspections and measures for nuclear power plants; international frame for inspections; action plan and WENRA reference level; action plan for the implementation of measures form robustness enhancement in German nuclear power plants (SNC topics 1-3), action plan for implementation of further measures (CNS topics 4-6).

  10. Multiple endocrine neoplasia (MEN) - like syndrome and other hormonal factors of promotion and progression of thyroid gland cancer in males-liquidators of Chernobyl accident consequences

    The clinical and laboratory endocrinological screening performed in 1,000 males - liquidators of Chernobyl accident consequences revealed hormonal factors leading to node formation and having unfavourable influence on progression and promotion of thyroid gland cancer. The factors include syndrome of low thriiodothyronine, hyperprolactinemia, latent hypothyrosis and increased production of thyroglobulin. Peculiarities of hormonal status in liquidators allow us to suggest the presence of MEN-like syndrome among the liquidators population. Possible mechanisms of expression of RET oncogene in adults that may result in MEN- like syndrome have been discussed. (author)

  11. [Informational and analytical system for the support of decision making during liquidation of consequences of a large-scale radiation accident].

    Zlatoustov, N N; Bizin, I A; Bondarenko, I M; Kaganov, V M; Grenkova, G K

    2001-07-01

    The developed information and analytic system (IAS) of decision making support in liquidation medical-and-sanitary consequences of the large-scale radiation accidents permits on the base of computer models to evaluate the size and degree of territorial radioactive pollution, the radiation doses, the number and structure of radiation affection, the forces and means of medical service required for rendering the casualties the first medical aid as well as to compare the available and necessary medical forces and means. IAS is intended for equipping the toxicologist-radiologist's working place. To solve the private problems the IAS computer methods can be used both in complex and autonomously. PMID:11561428

  12. Information-Analytic support of the programs of eliminating the consequences of the Chernobyl accident: gained experience and its future application

    On the initial stage of eliminating the consequences of the Chernobyl accident, the role of system-analytic and information support in the decision making process for protection of the population and rehabilitation of territories was. to a certain extent, underestimated. Starting from 1991, activity in system-analytic support was the part of the USSR (later on, Russian) stage programs. This activity covered three direction: development of the Central bank of the generalized data on the radiation catastrophes; development, implementation, and maintenance of the control informational system for the Federal bodies; computer-system integration

  13. Estimation of Public Health consequences of Tchernobyl nuclear accident (26 April 1986) based on CEA centers measurements

    Based on fallout measurements, additional radiation doses to the French population from external exposure to the plume, inhaled radioactivity and consumption of milk, meat and vegetables, have been estimated for the first period following the Chernobyl accident, by the various CEA centers in different regions of the country. Effective dose equivalent from the various exposures and radiation measurements in the different centers are presented in tables

  14. Main aspects of the design of a support structure of a LMFBR with particular reference to the explosive accident consequences

    The aim of this paper is a review of the main aspects of the design of a support structure of a LMFBR tank, with particular reference to the analysis of the non-linear dynamic behavior of the structure in the plastic range under the effect of an explosive accident within the tank. The structure is composed by a L-shaped flange, which supports the tank, connected by means of nine square beams to a rigid box-type ring, fixed to the concrete. The plug of the tank is connected to the L-shaped flange by means of a group of SS bars. The non-linear dynamic analysis of the explosive accident has been carried out on a lumped mass model, with elastic-plastic elements which simulate main components of the support structure and tank. The impulsive load connected to the explosive accident has been modelled (on the basis of extensive comparative studies carried out) as two triangular pressure impulses has been the object of a parametric evaluation. The dynamic transient on the support structure during and after the explosive accident for each couple of pressure impulses has been analyzed by means of modified version of the NON SAP code running on a CDC 7600 computer. A large amount of results, which describe displacements, velocities and accelerations of the plug, of the tank, and of the support structure, together with the forces and stresses acting on the main structural components are presented and discussed, with particular reference to the influence of the various parameters involved in the analysis

  15. CEC/CIS collaboration projects on the consequences of the Chernobyl accident preliminary results on the project dealing with strategies of decontamination

    In 1992, an agreement was signed between the Commission of the European Communities (CEC) and the relevant Ministries of Belarus, Russia and Ukraine in order to mitigate the consequences of the Chernobyl accident, through the implementation of a collaboration program involving the participation of about 200 CIS (Commonwealth of Independent States) and EU (European Union) Institutes and Research Centers. In such a context, a collaboration project aiming at evaluating strategies of decontamination for the territories affected by the accident was launched. This project not only dealt with decontamination of agricultural soils, urban areas and forests but also included treatment of contaminated foodstuff. To date, the project comprised both experimental and theoretical activities. It is expected that the results of this project can be used for the development of practical strategies for decontaminating the relevant CIS territories, as well as for the definition of appropriate policies in the event of a future nuclear accident. Relying on a strong collaboration network which was progressively established between EU and CIS scientists, field experiments mainly dealt with decontamination of meadows using a turf harvester, and forests while producing valuable wood derivatives

  16. German (GRS) approach to accident analysis (part III). Status of uncertainty evaluations of thermal-hydraulic code results in Germany

    There is an increasing interest in computational reactor safety analysis to replace the conservative evaluation model calculations by best estimate calculations supplemented by a quantitative uncertainty analysis. Sources of uncertainties - code models, initial and boundary conditions, plant state, fuel parameters, scaling, and numerical solution algorithm. Measurements, which are the basis of computer code model, show a scatter around a mean value. For example, data for two-phase pressure drop show a scatter range of about ± 20 - 30%. A range of values should be taken into account for the respective model parameter instead of one discrete value only. The state of knowledge about all uncertain parameters is described by ranges and subjective probability distributions. Stochastic variability due to possible component failures of the reactor plant is not considered in an uncertainty analysis. The single failure criterion is taken into account in a deterministic way. The aim of the uncertainty analysis is at first to identify and quantify all potentially important uncertain parameters. Their propagation through computer code calculations provides subjective probability distributions (and ranges) for the code results. The evaluation of the margin to acceptance criteria, (= technical limit value) e.g. the maximum fuel rod clad temperature, should be based on the upper limit of this distribution for the calculated temperatures. Investigations are underway to transform data measured in experiments and post-test calculations into thermal-hydraulic model parameters with uncertainties. It is effective to concentrate on those uncertainties showing the highest sensitivity measures. The state of knowledge about these uncertain input parameters has to be improved, and suitable experimental as well as analytical information has to be selected. This is a general experience applying different uncertainty methods

  17. Developing and implementing a computer assisted emergency facility for assessing off-site consequences due to accidents in UK nuclear power reactors

    This paper outlines considerations in the development of the RAD computer code as used in the Emergency Room at HM NII for assessing off-site consequences of accidents in UK civil nuclear power reactors. A wide range of requirements have been accommodated within the facility, particularly the need of HM NII to meet its responsibilities by producing realistic and timely estimates of a suitably high quality for propagating advice. The development of the computer code has required the balancing of many competing factors. Valuable experience has been gained by using the code during emergency exercises. Importance is laid on the feedback of field measurements to enhance the accuracy of estimated radiological consequences. (author)

  18. Australia's role during the crisis and consequence management phase of the Fukushima Dai-ichi NPP accident

    In the aftermath of the nuclear accident following the Great Last-Japan earthquake and tsunami disaster, Australia provided extensive advice to its citizens living, working, visiting or returning from Japan. This assistance was underpinned by provision of nuclear and radiation protection advice from ARPANSA, in collaboration with the Chief Medical Officer of the Department of Health and Ageing. During the first weeks of the accident this advice was provided and updated every 6 hours to the Australian Government in detailed briefing material and to members of the public via the ARPANSA website. Regular advice was provided on: protective measures for Australians in Japan including shelter in place Evacuation of Australians from affected areas; the availability and use of potassium iodide tablets for Australians in Japan; Precautions on consumption of contaminated food and water; transport directions of airborne radioactive material; status of Nuclear Power Plants and Nuclear Fuel storage facilities; frequently asked questions for medical practitioners; restriction on shipping to Japan. Provision of briefing material, information and general advice was underpinned by the routine assessment of the status of reactors and storage facilities and resulting environmental releases from information supplied by the Japan Government, TEPCO, and International Agencies like the IAEA. Protective measures were determined from the estimation of radiation doses for locations in Japan based on credible scenarios and atmospheric dispersion modelling using generic interventional levels as defined in the Radiation Protection Series 'Recommendations for Intervention in Emergency Situations Involving Radiation Exposure (2004).' This presentation provides an overview of Australia's response to the nuclear accident and ARPANSA's capability and methodology in providing advice.

  19. The main results of fulfilment in 1996 of the scientific part of the State programme of the Republic of Belarus for minimization and overcoming of the Chernobyl NPP accident consequences (1996-2000)

    In the publication are summarized the basic results of the researches executed in 1996 in the framework of the 'Scientific maintenance of the decision of problems of the Chernobyl NPP accident consequences' of the State program of Republic of Belarus for minimization and overcoming of the Chernobyl NPP accident consequences on 1996-2000 on the following directions: dose monitoring of the population, estimation and forecast of both collective irradiation dozes and risks of radiation induced diseases; development and optimization of a complex of measures for effective land use and decrease of radioactive contamination of agricultural production in order to reduce irradiation dozes of the population; development of complex technologies and means of decontamination, processing and burial of radioactive wastes; development of the measures for increase of radiation protection of the population of Belarus during of the reducing period after the Chernobyl accident; development of complex system of an estimation and decision-making on problems of radiation protection of the population living on contaminated territories; study of influence of radiological consequences of the Chernobyl accident on health of people, development of methods and means of diagnostics, treatment and preventive maintenance of diseases for various categories of the victims; development of effective methods of preventive maintenance and treatment of diseases of both mother and child in conditions of influence of the Chernobyl NPP accident consequences; study of genetic consequences caused by the Chernobyl accident and development of effectual measures of their prevention; creation of the effective both prophylactic means and food additives for treatment and rehabilitation of the persons having suffered after the Chernobyl accident; study of the radioisotopes behaviour dynamics in environment (air, water, ground), ecosystems and populated areas; optimization of the system of radiation ecological

  20. Evaluation of sanitary consequences of Chernobylsk accident in France. Epidemiological surveillance plan, state of knowledge, risks evaluation and perspectives; Evaluation des consequences sanitaires de l'accident de Tchernobyl en France. Dispositif de surveillance epidemiologique, etat des connaissances, evaluation des risques et perspectives

    Verger, P.; Cherie-Challine, L

    2000-12-15

    This report jointly written by IPSN and InVS, reviews the sanitary consequences in France of the Chernobyl accident, which occurred in 1986. The first point is dedicated to a short presentation of the knowledge relative to the sanitary consequences of the Chernobyl accident in the high contaminated countries and to the risk factors of the thyroid cancer. Secondly, this report describes the main systems of epidemiological surveillance of health implemented in France in 1986 and in 1999, as well as the data of the incidence and mortality of thyroid cancer observed in France since 1975. In addition, this report presents an analysis of the risk of thyroid cancer related to radioactive contamination in France, for young people of less than 15 years of age who where living in 1986 in the highest contaminated areas of France (Eastern territories). For this purpose, the theoretical number of thyroid cancers in excess is evaluated for this population, on the basis of different available risk model. Finally starting from the results of risk assessment, there is a discussion about the relevance and the feasibility of different epidemiological methods in view of answering the questions related to the sanitary consequences of the Chernobyl accident. In conclusion, this report recommends to reinforce the surveillance of thyroid cancer in France. (author)