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:
in the number of failures attributable to unanticipated degradation, including possible increases in common cause failure mechanisms. 19.2-25 June 2007 Reviewers should evaluate the implementation and monitoring strategies on the basis of findings obtained from the traditional engineering and probabilistic evaluations. When broad implementation is proposed over a short period of time, reviewers should verify that this is consistent with the traditional engineering evaluations, defense-in-depth considerations (including common cause failure), and risk-evaluation models and assumptions. When there is a need to gain additional performance insights given a change in requirements, reviewers should verify that the licensee has proposed a phased approach to implementation. If this phased approach involves plan implementation for different SSC groups at different times, reviewers should also assess the basis for the licensee’s grouping criteria, keeping in mind the potential common cause failures. Monitoring should be applied to SSCs in a manner commensurate with their importance to safety as determined by the engineering evaluation that supports the LB change. This monitoring should be contingent on the reliability/availability allocated to SSCs in the risk model (or on performance of operators, where appropriate) used to support the proposed change in regulation. As such, reviewers should ensure that the chosen performance criteria are consistent with the level of performance allocated in the risk analysis. When monitoring that is already being performed as part of the Maintenance Rule implementation or as part of other plant programs is also proposed for the current application, reviewers should ensure that the monitoring proposed is sufficient for the SSCs affected by the risk-informed application and that the performance criteria chosen are appropriate for the application in question. As part of the evaluation of the licensee’s monitoring program, reviewers should