Document: NUREG-0800
Document ID: fe8ec6c2-e960-404c-854f-55c77bde1672
Document Type: srp
Title: NUREG-0800
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML2400/ML24005A077.pdf
Revision Date: 2024-05
Chapter: 7
Section ID: 7
CFR Part: 
CFR Title: 

Content:
tand the limitations associated with some PRA models related to CCFs. One limitation is that some PRA models do not include details of the hardware or software components of DI&C systems or of all the interdependencies across different SSCs. If an application uses a plant-specific PRA as part of its risk-informed approach to address a CCF, the reviewer should determine whether the application identifies the base PRA used to BTP 7-19-31 Revision 9 — May 2024 support the D3 assessment, and whether the base PRA meets the PRA acceptability guidance in RG 1.200 or equivalent guidance for new reactors such as DC/COL-ISG-028. The application may identify an approved risk-informed application that was supported by the same base PRA. The reviewer may leverage the previous risk-informed application to help determine the technical acceptability of the base PRA to support the D3 assessment. The application should justify the exclusion of any PRA hazard or operating mode from the D3 assessment. The application should also justify any changes made to the PRA model (beyond those needed to model the CCF) to support the application, including whether the changes are considered PRA maintenance or a PRA upgrade (typically based on the corresponding definitions in the application’s specified revision of RG 1.200 or equivalent guidance for new reactors, such as DC/COL-ISG-028). A change made to a PRA model, including the use of a newly developed method, may be classified as PRA maintenance or a PRA upgrade. RG 1.200 provides guidance for classifying changes to a PRA model as PRA maintenance or a PRA upgrade. The reviewer should consider any guidance used (e.g., the specific revision of RG 1.200 or DC/COL-ISG-028) for configuration control of the PRA supporting the application. The reviewer should confirm whether any changes made to the PRA model constitute PRA maintenance or a PRA upgrade, based on the corresponding definition in the identified guidance. SRP Section 19.2 provides