Document: NUREG-0800
Document ID: 7916b088-fb90-4163-84fe-027bd315bcc5
Document Type: srp
Title: REVIEW OF RISK INFORMATION USED TO SUPPORT PERMANENT PLANT-
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0717/ML071700658.pdf
Revision Date: 2023-06
Chapter: 19
Section ID: 19.2
CFR Part: 
CFR Title: 

Content:
, the disposition of these issues was systematic 19.2-73 June 2007 and defensible, and the documentation of the findings is traceable and reviewable in principle, so that the basis for conclusions and recommendations is available for scrutiny and review. • The evaluation of risk significance represents appropriate consideration of probabilistic information, traditional engineering evaluations, sensitivity studies, operational experience, engineering judgment, and current regulatory requirements. • The technical information basis was adequate for the scope of the application. In particular, the analysis of success and failure scenarios was adequate to identify the roles played by the SSCs affected by the application, the quantification of the frequency of these scenarios was adequate to establish the safety significance of the SSCs, and the causal models were adequate to establish the effects of the proposed changes in the program. • The safety significance of components affected by the proposed application but not modeled in the PRA was evaluated in a systematic manner. This included a search of components that might contribute to initiating event occurrence, mitigating system components that were not modeled in the PRA because their failure was not expected to dominate system failure in the baseline configuration, and components in systems that do not play a direct role in accident mitigation but do interface with accident mitigating systems. • The process applied by the licensee to overcome limitations of PRA was appropriate. Where decisions were made that do not follow straightforwardly from the PRA, a technical basis was provided that shows how the PRA information and the supplementary information validly combine to support the finding. No findings contradict the PRA in a fundamental way. 19.2-74 June 2007 APPENDIX C Categorization of Plant Elements with Respect to Safety Significance For several proposed applications in risk-informed regulation, one of