With the ever advancing state of computer systems, it is imperative to maintain the most up-to-date and reliable safety evaluation data for nuclear power systems. Commonplace now is the practice of updating old accident simulation results with more advanced models and codes using today's faster computer systems. Though it may be quite an undertaking, the benefits of using a more advanced model and code can be significant especially if the result of the new analysis provides increased safety margin for any plant component or system. A series of parametric and sensitivity studies for the Loss of Normal Feedwater Anticipated Transient without Scram (LONF ATWS) for Southern Company's Vogtle Electric Generating Plant (VEGP) Units 1&2 located near Waynesboro, GA was performed using the best-estimate thermal-hydraulics transient analysis code RETRAN-02w. This thesis includes comparison to the results of a generic plant study published by Westinghouse Electric Corporation in 1974 using an earlier code, LOFTRAN, as well as Vogtle-specific analysis. The comparative analysis exposes and seeks to explain differences between the two codes whereas the Vogtle analysis utilizes data from the Vogtle FSAR to generate plant-specific data. The purpose of this study is to validate and update the previous analysis and gather more information about the plant actions taken in response to a LONF ATWS. As a result, now there is a new and updated evaluation of the LONF ATWS for both a generic 4-loop Westinghouse plant and VEGP using a more advanced code. Beyond the reference case analysis, a series of sensitivity and parametric studies have been performed to show how well each type of plant is designed for handling an ATWS situation. These studies cover a wide range of operating conditions to demonstrate the dependability of the model. It was found that both the generic 4-loop Westinghouse PWR system and VEGP can successfully mitigate a LONF ATWS throughout the core's operating cycle.

In this thesis we look at one of the aging mechanisms that may have affected current aged Nuclear Power Plants (NPPs). Irradiation as an age-related degradation mechanism is studied for Reinforced Concrete (RC) in NPPs. This problem can be important for aged reactor buildings, radwaste buildings, spent nuclear fuel, research reactors, or accelerators that experience high levels of radiation close to existing thresholds. Mechanical properties of concrete are the most important parameters affected by radiation in NPPs. Compressive strength of concrete is reduced between 80 and 35 \% for radiation fluences between $2\times 10^{19}$ and $2\times 10^{21} n/cm^2$. Tensile strength reduction is more significant than compressive strength. It is reduced between 20 and 80 \% for a radiation fluence equal to $5\times 10^{19}$. We chose three radiation levels $2\times 10^{19}$, $2\times 10^{20}$, $2\times 10^{20}$ based on experimental results as the critical levels of radiation that RC structures in NPPs may be exposed to. Structures susceptible to the problem are mostly RC walls; so the RC panel is chosen as an appropriate representative scale element for the analysis. The effect of radiation on mechanical properties of concrete is considered to analyze degraded scale elements. Material properties, geometry, and loading scenarios of scale elements are selected to be close to actual quantities in existing nuclear power plant. Elements are analyzed under six types of loading combination of shear and axial loading conditions. A nonlinear finite element program, Membrane-2000, based on the Modified Compression Field Theory (MCFT) is used to solve scale elements numerically. Element behaviors are studied considering the factors influence ultimate strength capacity, failure mode, and structural ductility index of members. The results show that ultimate shear capacity of the elements subjected to combinations of shear and tension loading are reduced significantly for highly reinforced elements ($1.35<\rho<1.88$) in $2\times 10^{21} n/cm^2$ radiation. RC panels under shear-biaxial and uniaxial compression also show significant strength capacity reduction in radiation levels $2\times 10^{20} n/cm^2$ and $2\times 10^{21} n/cm^2$, respectively. Failure modes of the elements change from yielding of steel to shear failure by increasing level of degradation for the elements with reinforcement ratio between 0.9 and 1.88. Ductility of the RC panels is reduced significantly in the critical levels of radiation. Ductility of the elements became less than the allowable ductility value by increasing level of radiation.

A comunidade da Vila do Frade encontra-se localizada a 5 km de distância em linha reta do reator da central Nuclear almirante Álvaro Alberto, angra dos Reis, RJ. Possui uma população heterogênea, miscigenada por intensos processos de migração ocorridos a partir da década de 1960 em busca das oportunidades de emprego oferecidos pela industrialização local. Ao longo do tempo, parte dessa população assumiu o risco de morar próximo a um reator nuclear, e por isso, migrou em direção as ofertas de emprego oferecidas pelas atividades da central nuclear. Porém, outra parte da população, já residente na região antes da instalação dos reatores nucleares, foi obrigada a conviver com os riscos ou a migrar. À medida que as transformações territoriais avançaram pelas diferentes áreas do município passaram a expor a sociedade local a riscos nunca antes experimentados. Entendido como um processo ou o produto da frequência de ocorrência de um evento no tempo, o risco pode ser assumido, gerenciado ou negligenciado. Dessa forma, a presente pesquisa buscou, através de um estudo empírico, compreender como os diferentes agentes sociais locais convivem com os riscos da atividade nuclear. Foi objetivo da pesquisa a análise da concepção do conceito e da condição de risco por parte dos diferentes agentes sociais constituintes da comunidade da Vila do Frade, Angra dos Reis. Além disso, foi discutido o papel do Estado no processo do ordenamento territorial local. Para tal, uma metodologia baseada no estudo da percepção ambiental dos diferentes agentes sociais locais foi elaborada. As atividades foram precedidas de um levantamento bibliográfico capaz de dar suporte as investigações, além disso, foram realizadas entrevistas quantitativas e qualitativas com as diferentes representações sociais local. As entrevistas quantitativas foram organizadas num banco de dados e utilizadas para compor uma caracterização da população local no que se refere aos conhecimentos necessários para a aplicação do plano de emergência externo da central nuclear. As entrevistas qualitativas foram organizadas num questionário semiestruturado, composto por perguntas abertas e fechadas, e tiveram como objetivo geral uma compreensão da influência da central nuclear nos processos de desenvolvimento humano local. Para a maioria dos entrevistados a falta de um instrumental metodológico capaz de abranger com maior eficiência todas as áreas, classes sociais da comunidade da Vila do Frade e levar com clareza as questões que se colocam dentro do plano de emergência externo são apontados como o principal fator de risco existente na região. / The community of Vila do Frade is located 5 km away, on a straight line, from the reactor of the nuclear power plant Almirante Álvaro Alberto, Angra dos Reis, RJ . It has a heterogeneous population, mixed-race from intense migration processes, which started occurring inthe 1960s, in search of employment opportunities offered by the local industrialization. Over time, part of this population took the risk of living near a nuclear reactor, and, therefore, migrated towards the jobs offered by the activities of nuclear power plant. However, another part of the population, resident in the region before the installation of nuclear reactors, was forced to live with the risk or to migrate. As the territorial transformations advanced through different areas of the city, the local community started being exposed to risks they had never experienced before. Understood as a process or the product of the frequency of occurrence of an event in time, the risk can be assumed, managed or neglected. Thus, this research sought, through an empirical study, to understand how the different local social agents live with the risks of nuclear activity. Objective of the research was the analysis of the concept design and the condition of risk by social workers of the different constituents of the Vila do Frade, Angra dos Reis community. Moreover, discussed the role of the state in local land use planning process. To this end, a methodology based on the study of the environmental perception of different local social agents was prepared. The activities were preceded by a bibliographical survey capable of supporting investigations; moreover, quantitative and qualitative interviews with different social local representations were made. The quantitative interviews were organized in a database and used to compose a characterization of the local population with regard to the knowledge needed to implement the external emergency plan for nuclear power plant. The qualitative interviews were arranged in a semi-structured questionnaire consisting of open and closed questions, and with the overarching goal of an understanding of the influence of nuclear power plant in the processes of local human development. For most respondents, the lack of a methodological tool able to cover more efficiently all areas and social classes of the community Vila do Frade and to clearly lead the issues that arise within the external emergency plan are pointed out as the main factor of risk that exists in the region.

Active Particles at the Temelin NPP, Radiobiological Risks and Protective Precautions The term active particle (AC) was applied on Temelín NPP (ETE) in order to denominate small fragments of high radioactive matters, sized up to 1 millimeter, forming into primary circuit. In accordance with latest available know-how, the ACs major contains corrosion products, that were activated during passing through reactor core. After primary circuit opening, due to carry out outage works, the ACs will spread into ETE radiation controlled area. In proportion to their size, the ACs activity is relative high, so that the ACs can jeopard workers, who will contact them. This jeopardy is namely associated with AC penetration into organism - ingestion or inhalation. The main goal of this dissertation is to determine grounds of ACs occurence in Temelín NPP, to review ACs radiobiological risks and to evaluate procedures and protective aids, used for assurance of workers radiation protection. This dissertation is resuming actual know-how about ACs occured and occuring in Temelín NPP, including suggestions for radiation protection procedures and for protective aids utilization, that are to be used for reduction of above mentioned jeopardy. Next areas are concerned: - analysis of ACs forming and matters composition - description of ACs physical-radiation parameters - identification of main ACs sources in primary circuit - assesment and evaluation of radiobiological jeopardies, associated with ACs occurence in Temelín NPP radiation controlled area - assesment of procedures and protective aids used for protection of workers, who can be endangered by ACs

Made available in DSpace on 2015-07-22T20:50:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-01-30 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Associação Fundo de Incentivo à Psicofarmacologia (AFIP) / Centros de Pesquisa, Inovação e Difusão (CEPID) / Centro de Estudos Multidisciplinar em Sonolência e Acidentes (CEMSA) / Os trabalhadores em turnos das usinas nucleares devem manter um alto desempenho e atenção ao longo do seu turno. No entanto, encontra-se consolidado na literatura que os distúrbios do sono podem prejudicar a atenção e o desempenho dos trabalhadores que são submetidos a diferentes horários de sono. Objetivo: O objetivo deste estudo foi descrever as queixas subjetivas sobre o sono e os parâmetros polissonográficos dos trabalhadores em turnos das usinas nucleares brasileiras. Método: Foi realizada uma avaliação subjetiva com a aplicação do Questionário UNIFESP do sono, no qual os trabalhadores que relataram alguma queixa referente ao sono, foram encaminhados para a realização de uma avaliação polissonográfica noturna. Resultados: Dos 327 trabalhadores que responderam ao questionário, 113 relataram queixas de sono; sendo estes também mais velhos, com um maior IMC e que trabalhavam por turnos há mais tempo, quando comparados aos sem queixas de sono. Dentre os 113 que apresentaram queixas e que foram encaminhados para a polissonografia, 90 apresentaram alterações no sono, apresentando como resultado uma maior proporção no estágio 1, um maior índice de microdespertares, um maior índice de apnéia e de hipopnéia e um maior índice de movimento das pernas, quando comparados com os demais. Destes, 18 (20%) apresentaram movimentos periódicos de pernas, 30 (33%) foram considerados como tendo apnéia, e 42 (47%) apresentaram estas duas condições combinadas. A maioria dos casos foi considerada como de grau leve. Conclusões: De maneira geral, os dados do presente estudo corroboram com os já evidenciados na literatura os quais mostram que, subjetivamente (no questionário), os trabalhadores em turnos apresentam queixas de sono. E com a polissonografia xi ii foi constatado que além de queixas a grande maioria dos trabalhadores apresenta índices preditores de distúrbios do sono. As porcentagens encontradas são próximas às da população em geral, mas é importante ressaltar que estas queixas influenciam diretamente para uma diminuição da qualidade de vida destes trabalhadores bem como, no que diz respeito ao desempenho e o aumento do risco de acidentes durante a jornada de trabalho. / It is widely recognized in the literature that shift workers present more health complaints than the general population. The objective of this study was to describe and diagnose the sleep complaints and sleep disorders of shift workers in two Brazilian Nuclear Power Plants. Three hundred and twenty seven (327) shift workers participated in the study. They worked in three rotating shifts: afternoon (3pm-11pm), morning (7am-3pm) and night (11pm-7am). We carried out a subjective evaluation with a sleep questionnaire. Based on these results, the interviewees that reported sleep-related complaints more than three times a week were referred for a Polysomnographic Evaluation. Out of the 327 volunteers initially evaluated, 145 were referred to Polysomnography. Of these, 111 (34%) workers presented some kind of sleep disorder, these being: 31 (21%) with Obstructive Sleep Apnea (OSA) and 30 (21%) with Periodic Limb Movement (PLM). Fifty subjects (34%) presented both disorders and 34 (23%) presented none. The present study shows that 37% of the population evaluated presented some sort of sleep disorder. This high percentage should be investigated for associations with other aspects of work, such as working hours, working schedule, years performing shift work and access to health services. Due to the strong association between sleep disorders and the incidence of fatigue and sleepiness (and, therefore, a higher probability of accidents), the evaluation of the sleep patterns and complaints of shift workers is essential and should be considered to be one of the basic strategies of the companies to prevent accidents. / FAPESP: 05/57.525-1 / CEPID: 98/14303-3 / TEDE / BV UNIFESP: Teses e dissertações

The thesis deals with the solution to evacuation of the population from the zone of emergency planning of the nuclear power station Temelín in the event of an incident connected with the release of radioactive substances . It analyzes the way of evacuation of the persons, as one of the most important safety measures to ensure protection of the population. In particular, the work focuses on the correct procedures in the case of realization of the evacuation and competence of the persons involved in safety measures. It lists the basic criteria which are applied in protection of the population from the effects of ionizing radiation in vicinity of nuclear power plants. It proposes improving of quality of security protection and information of persons in the zone of emergency planning. The work is based on valid law regulations and special publications of the examined problems. The predominantly part is based on the laws in force, and expertise of publications covering the evacuation of the area.It refers to the external emergency plan, as the basic document for the planning of measures for the disposal of the consequences of radiation accidents or radiation accidents and the limitation of their consequences for the zone of emergency planning. The theoretical part proceeeds from analysis of contemporary legislation concerning the stated problematics, presents the general characteristics of a nuclear device and zone of emergency planning, defining the basic concepts and discusses the important measures in addressing emergencies arising in connection with radiation accidents in nuclear power plant. The work puts emphasis on the principle of correct behaviour of the population in the event of such an accident. For the processing of the thesis there has been used an exploration method, which is based on the proposed methodology. On the base of analysis of survey, possible ways of improvement of this branch were suggested. From the collected data there have been assessed possible system measures of evacuation with regard to their application in practice.

A comunidade da Vila do Frade encontra-se localizada a 5 km de distância em linha reta do reator da central Nuclear almirante Álvaro Alberto, angra dos Reis, RJ. Possui uma população heterogênea, miscigenada por intensos processos de migração ocorridos a partir da década de 1960 em busca das oportunidades de emprego oferecidos pela industrialização local. Ao longo do tempo, parte dessa população assumiu o risco de morar próximo a um reator nuclear, e por isso, migrou em direção as ofertas de emprego oferecidas pelas atividades da central nuclear. Porém, outra parte da população, já residente na região antes da instalação dos reatores nucleares, foi obrigada a conviver com os riscos ou a migrar. À medida que as transformações territoriais avançaram pelas diferentes áreas do município passaram a expor a sociedade local a riscos nunca antes experimentados. Entendido como um processo ou o produto da frequência de ocorrência de um evento no tempo, o risco pode ser assumido, gerenciado ou negligenciado. Dessa forma, a presente pesquisa buscou, através de um estudo empírico, compreender como os diferentes agentes sociais locais convivem com os riscos da atividade nuclear. Foi objetivo da pesquisa a análise da concepção do conceito e da condição de risco por parte dos diferentes agentes sociais constituintes da comunidade da Vila do Frade, Angra dos Reis. Além disso, foi discutido o papel do Estado no processo do ordenamento territorial local. Para tal, uma metodologia baseada no estudo da percepção ambiental dos diferentes agentes sociais locais foi elaborada. As atividades foram precedidas de um levantamento bibliográfico capaz de dar suporte as investigações, além disso, foram realizadas entrevistas quantitativas e qualitativas com as diferentes representações sociais local. As entrevistas quantitativas foram organizadas num banco de dados e utilizadas para compor uma caracterização da população local no que se refere aos conhecimentos necessários para a aplicação do plano de emergência externo da central nuclear. As entrevistas qualitativas foram organizadas num questionário semiestruturado, composto por perguntas abertas e fechadas, e tiveram como objetivo geral uma compreensão da influência da central nuclear nos processos de desenvolvimento humano local. Para a maioria dos entrevistados a falta de um instrumental metodológico capaz de abranger com maior eficiência todas as áreas, classes sociais da comunidade da Vila do Frade e levar com clareza as questões que se colocam dentro do plano de emergência externo são apontados como o principal fator de risco existente na região. / The community of Vila do Frade is located 5 km away, on a straight line, from the reactor of the nuclear power plant Almirante Álvaro Alberto, Angra dos Reis, RJ . It has a heterogeneous population, mixed-race from intense migration processes, which started occurring inthe 1960s, in search of employment opportunities offered by the local industrialization. Over time, part of this population took the risk of living near a nuclear reactor, and, therefore, migrated towards the jobs offered by the activities of nuclear power plant. However, another part of the population, resident in the region before the installation of nuclear reactors, was forced to live with the risk or to migrate. As the territorial transformations advanced through different areas of the city, the local community started being exposed to risks they had never experienced before. Understood as a process or the product of the frequency of occurrence of an event in time, the risk can be assumed, managed or neglected. Thus, this research sought, through an empirical study, to understand how the different local social agents live with the risks of nuclear activity. Objective of the research was the analysis of the concept design and the condition of risk by social workers of the different constituents of the Vila do Frade, Angra dos Reis community. Moreover, discussed the role of the state in local land use planning process. To this end, a methodology based on the study of the environmental perception of different local social agents was prepared. The activities were preceded by a bibliographical survey capable of supporting investigations; moreover, quantitative and qualitative interviews with different social local representations were made. The quantitative interviews were organized in a database and used to compose a characterization of the local population with regard to the knowledge needed to implement the external emergency plan for nuclear power plant. The qualitative interviews were arranged in a semi-structured questionnaire consisting of open and closed questions, and with the overarching goal of an understanding of the influence of nuclear power plant in the processes of local human development. For most respondents, the lack of a methodological tool able to cover more efficiently all areas and social classes of the community Vila do Frade and to clearly lead the issues that arise within the external emergency plan are pointed out as the main factor of risk that exists in the region.

This thesis deals with the influence of the discharges of the Dukovany Nuclear Power Plant ("Dukovany NPP") and the assessment of impacts on the population and the vicinity of the power plant. The thesis summarizes the issues of tritium 3H discharges into waterways and partially deals with the 14C discharges. Attention is paid especially to the radioisotope of hydrogen 3H, due to its chemical and physical form and its presence in the cooling medium (light water) used by that type of nuclear power reactor. The thesis also contains a description of the current state of the Dukovany NPP, especially the existing discharges of the radioactive substances to the surroundings of the nuclear power plant, both to the air and into the waterway. Also was discussed the issue of the new planned blocks of the Dukovany NPP and impacts of the projected discharges on the population during the simultaneous operation of the existing blocks and the planned blocks, again in relation to the 3H discharged into the waterway. The application ESTE AI was used for the determination of individual groups of inhabitants who are most exposed to the radioactive discharges (also called representative person). Based on the current discharges of the Dukovany NPP and the planned blocks discharges were determined the annual effective doses for a representative person. The doses were compared with the legislation on the conditions for the peaceful use of nuclear energy requirements and then with the water management legislation. In order to avoid exceeding these limits were set up recommendations how to dispose of radioactive substances optimally. The thesis answer to the research question: What impacts on the population will have discharges of the Dukovany NPP after the construction of a new nuclear source, especially in relation to the discharges of the 3H into the waterway and which measures will must be applied on the optimization of the inhabitants doses.

This work deals with occupational professional exposures at Temelín Nuclear Power Plant. The introductory part is devoted to types of ionising radiation participating on radiation load of workers, values and units and to the essential legislation requests associated with individual monitoring. In the following part characteristics of methods used to measure individual doses of external exposures like film dosimetry, thermoluminescent do-simetry, radio-photoluminescent dosimetry and electronic dosimetry are described. For assessment of the committed effective dose from the internal exposures in vivo moni-toring or indirect measuring were used. The possibilities of the occupational dose optimisation were discussed Results of individual monitoring in 2005 and 2006 and layout of monitoring program are presented in this work. The new monitoring program is based on the active personal dosimeters (EPDs) rather than on the passive ones and covers the period of transformation between them. With respect to the passive dosimeters, EPDs offer some advantages which on one hand contribute to a better exposure control and on the other hand foster the development of a sound culture in radiation protection due to direct feedback of dose information.

In this work, which deals with problematics of releases from nuclear power plants, I tried to make an overview of various types of nuclear power plants and radioizotopes which are released through liquid and gasseous effluents. As a part of this comparison evaluation of czech and world nuclear power plants gaseous and liquid releases was made. Introductory part of this work contains information about different types of nuclear power plants and radioizotopes, which are produced in their reactors. It continues with today{\crq}s legislative and information about releasing levels and methods and systems used for measurement of radioactive gaseous and liquid effluents from nuclear power plants. Second part of this work describes the aim of this work and hypothesis. Third part explains the methods, which were used for completing of this work. Fourth part contains results in the form of tables and graphs. Fifth part represents discussion of the results. Last part is a summarization of the results.