Document: NUREG-0800
Document ID: ac43f632-9db1-4857-9f56-bfba45965456
Document Type: srp
Title: * These are modifications to a plant’s design, operations, or other activities that require NRC approval. These modifica
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0232/ML023250195.pdf
Revision Date: 2023-06
Chapter: 19
Section ID: 19
CFR Part: 
CFR Title: 

Content:
tally affect the quality of the technical analysis. • Results of the licensee's analysis submitted in support of a licensing action are in some way counter-intuitive or inconsistent with results for similar plants on similar issues. • The licensee's analysis is part of a pilot application of PRA in a regulatory activity. • The PRA includes new methods that are unfamiliar to the staff. When a staff review of the base PRA is necessary, reviewers should begin by evaluating the results and conclusions from available independent peer reviews of the PRA.* The staff review should take into account the process used in the peer review (including the review guidelines or standards to which the PRA is compared, the review scope and elements, the qualification and makeup of the review team, etc.). Results from previous staff reviews of the PRA (e.g., from previous applications) could also provide a good starting point. In cases where the PRA is based on the individual plant examination (IPE) or the IPE of externally initiated events (IPEEE) models, reviewers should also be familiar with the request for additional information (RAI) issued by the 3 The American Society of Mechanical Engineers (ASME) recently issued "Standard for Probabilistic Risk Assessment for Nuclear Power Plant Applications," ASME RA-S-2002, which covers Level 1 and Level 2 (LERF only) PRAs for internal events (excluding fire) that occur during full power operations. The American Nuclear Society (ANS) is developing a draft standard for external events (e.g., seismic, including seismic margins, wind, flood), "Standard for Probabilistic Risk Assessment for Nuclear Power Plant Applications: External Events." The ANS is also developing a draft standard for low power and shutdown conditions, "Standard for Probabilistic Risk Assessment for Nuclear Power Plant Applications: Low Power and Shutdown." In addition, the various engineering professional societies are considering developing a Standard for performing