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Michael W. Golay. Verdier, Edouard (Edouard Pierre Emmanuel) Environmental Defense Fund. Massachusetts Institute of Technology. Department of Nuclear Science and Engineering e-fr--- n-us--- 2013-01-23T19:50:33Z 2013-01-23T19:50:33Z 2012 2012 http://hdl.handle.net/1721.1/76537 824140349 Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Nuclear Science and Engineering, 2012. Cataloged from PDF version of thesis. "This study is part of a research project sponsored by EDF at MIT"--P. 3. Includes bibliographical references (p. 175-178). During the past twenty-five years, the US Nuclear Regulatory Commission has been progressing toward a more risk-informed, performance-based regulation. This regulatory framework has effectively supported the development of online maintenance practices. In France, while the safety authority has been encouraging particular risk-informed applications, PRA (Probabilistic Risk Assessment) techniques have not penetrated the nuclear regulatory framework and industry to the same extent. After presenting relevant differences between the French and US nuclear industries and regulatory frameworks, the development and use of risk-informed applications in both countries are reviewed. In the United States, these techniques are usually well-accepted and have brought positive results regarding operational performance, plant safety and regulatory efficiency. In France, there have been in some cases difficulties regarding the acceptability of these techniques with the safety authority, but also within the operating company. While PRA results are commonly used in the US at the operational level through the use of risk-monitors, there appear to be in France obstacles to such practices. Online maintenance regulations and practices are then presented. US technical specifications provide much flexibility to voluntarily enter technical specifications action statements for online maintenance. As a result, following the implementation of the Maintenance Rule, online maintenance has been increasingly applied, leading to operational as well as safety improvements. In France technical specifications are more restrictive regarding these aspects, and online maintenance of safety-significant systems is often not allowed or allowed under restrictive conditions. A case study concerning the maintenance of emergency diesel generators and emergency core cooling systems is presented to illustrate and study these points in more detail. Finally, possible directions to facilitate the implementation of an online maintenance strategy in France are identified, and their implications are discussed. by Edouard Verdier. S.M. 180 p. eng Massachusetts Institute of Technology M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission. http://dspace.mit.edu/handle/1721.1/7582 Nuclear Science and Engineering. Environmental Defense Fund. Risk-informed applications and online maintenance in France and the United States Thesis application/pdf false Publication unknown unknown <Publication xmlns="https://www.openaire.eu/cerif-profile/1.1/" id="3daf9b3d-375b-4f2e-a867-96605b6689b9"> <Type xmlns="https://www.openaire.eu/cerif-profile/vocab/COAR_Publication_Types">http://purl.org/coar/resource_type/c_1843</Type> <Language>eng</Language> <Title>Risk-informed applications and online maintenance in France and the United States</Title> <PublishedIn> <Publication> </Publication> </PublishedIn> <PublicationDate>2012</PublicationDate> <Authors> <Author> <DisplayName>Verdier, Edouard (Edouard Pierre Emmanuel)</DisplayName> <Affiliation> <OrgUnit> </OrgUnit> </Affiliation> </Author> </Authors> <Editors> </Editors> <Publishers> <Publisher> <DisplayName>Massachusetts Institute of Technology</DisplayName> <OrgUnit /> </Publisher> </Publishers> <License>http://dspace.mit.edu/handle/1721.1/7582</License> <Keyword>Nuclear Science and Engineering.</Keyword> <Keyword>Environmental Defense Fund.</Keyword> <Abstract>During the past twenty-five years, the US Nuclear Regulatory Commission has been progressing toward a more risk-informed, performance-based regulation. This regulatory framework has effectively supported the development of online maintenance practices. In France, while the safety authority has been encouraging particular risk-informed applications, PRA (Probabilistic Risk Assessment) techniques have not penetrated the nuclear regulatory framework and industry to the same extent. After presenting relevant differences between the French and US nuclear industries and regulatory frameworks, the development and use of risk-informed applications in both countries are reviewed. In the United States, these techniques are usually well-accepted and have brought positive results regarding operational performance, plant safety and regulatory efficiency. In France, there have been in some cases difficulties regarding the acceptability of these techniques with the safety authority, but also within the operating company. While PRA results are commonly used in the US at the operational level through the use of risk-monitors, there appear to be in France obstacles to such practices. Online maintenance regulations and practices are then presented. US technical specifications provide much flexibility to voluntarily enter technical specifications action statements for online maintenance. As a result, following the implementation of the Maintenance Rule, online maintenance has been increasingly applied, leading to operational as well as safety improvements. In France technical specifications are more restrictive regarding these aspects, and online maintenance of safety-significant systems is often not allowed or allowed under restrictive conditions. A case study concerning the maintenance of emergency diesel generators and emergency core cooling systems is presented to illustrate and study these points in more detail. Finally, possible directions to facilitate the implementation of an online maintenance strategy in France are identified, and their implications are discussed.</Abstract> <Access xmlns="http://purl.org/coar/access_right" > </Access> </Publication>