Restructuring and hierarchisation of component lists subject to QA(Q-Lists)

Until now, component lists subject to Quality Assurance (Q-lists) included every structure, system and component (SSC) related to safety, and therefore subject to Quality Assurance, in accordance with Appendix B of 10 CFR 50. This involves applying all Quality Assurance, maintenance, standardization, auditing, inspection, etc, procedures to a large number of components, which causes delay to and hinders to a large extent refuelling and maintenance times. The NRC is currently proposing the restructuring of the Q-lists, categorizing and establishing hierarchies for the SSCs based on their particular contribution to core damage. Significance categorization is made possible by previously determining the importance or risk significance of each SSC. To identify risk significant SSCs, NUMARC 93-01 shall be used as input data. The results of PSA and other deterministic criteria, eg RG 1.97. ATWS, etc, shall also be taken into account. Iberdrola is going to apply all these criteria in the case of Cofrentes NPP, which will lead to a substantial reduction in maintenance costs and the application of a more efficient Quality Assurance Programme, in keeping with the guidelines and latest NRC trends in this item. (Author)