Aging PSA as a Tool for Evaluation of Impact of Aging and Maintenance of SSC to the Overall Plant Safety

The paper will present a brief summary of EC JRC Aging PSA network activities and futures actions planned, as well as some results obtained from feasibility studies and benchmark exercises. Specific emphasis will be done on the task of reliability data and operating experience analysis and interpretation of the results. The Network on Incorporating Ageing Effects into Probabilistic Safety Assessment (Aging PSA) is under development within the framework of the JRC FP-6 institutional Project "Analysis and Management of Nuclear Accidents". The Aging PSA state of the arts “living report” (www.energyrisks.jrc.nl/APSA ) provides several examples of feasibility studies carried out by the network participants. The following case studies are performed or under development now : • Demonstration of statistical approaches to identify the component’s aging by operational data analysis, • Incorporation of Ageing and Maintenance Effects into System Reliability Models, • Investigation of component age dependent reliability models : representativness, uncertainties and predictive extrapolations. Some results of these activities will be presented and discussed. The main outputs from the network activities (2004-2006) could be summarized as follows ; • Aging PSA could be used as a complementary to the deterministic approach, for evaluation of SSC aging impacts to the overall plant safety, • related areas of applications are the Periodical Safety Review, Aging Management, Maintenance Optimization and Lifetime Extension activities, • incorporation of aging effects into the PSA model require important resources and time allocations, • methods and approaches of Aging PSA are not well developed for the moment and need additional R&D.JRC.F.4-Nuclear design safet