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:
to help reviewers evaluate PRA quality as a function of the application. Finally, Appendix C to this SRP section discusses review issues related to the determination of risk contribution and component categorization. III.2.2.1 Characterization of Change in Terms of PRA Model Elements Where quantitative PRA results are used as part of a risk-informed evaluation of a proposed change, the licensee should define the change in terms that are compatible with the risk analysis, i.e., the risk analysis should be able to effectively evaluate the effects of the change. The approach to risk characterization should establish a cause-effect relationship to identify portions of the PRA affected by the issue being evaluated. This includes (1) identifying the specific PRA contributors for the particular application, (2) assessing the portions of the model that should be modified for the application, and (3) identifying supplemental analyses that could 19.2-13 June 2007 be used to support the application. This approach will help reviewers determine the scope and level of detail of analysis required for the remaining steps in the change process. Table III-1 of this SRP section summarizes the general guidance for use in identifying elements of the PRA model that may be affected by an application. This guidance, presented as a list of questions, will assist reviewers in establishing a cause-effect relationship between the application and the PRA model. The answers to these questions should be used to identify the extent to which the proposed change affects the design, operation, and maintenance of plant SSCs. Reviewers should also verify that the effects of the proposed changes on plant elements (SSCs, operator actions, etc.) are adequately characterized in the elements of the PRA model or by appropriate changes to the logic model structure. For full-scale applications of the PRA, for example, this should be reflected in a quantification of the impact on the PRA results. For