Document: NRC Regulatory Guide
Document ID: 22ccfd5e-c5d8-4615-a02c-32369aa9f533
Document Type: regulatory_guide
Title: Acceptability of Probabilistic Risk Assessment Results for Risk-Informed Activities (Rev. 3)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML1930/ML19308B636.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.200
CFR Part: 
CFR Title: 

Content:
� endorses the following from PWROG-19027-NP, Revision 1, “Newly Developed Method Requirements and Peer Review” (Ref. 24): o requirements for the peer review of newly developed methods (NDMs) (see regulatory positions C.2.2.2 through C.2.2.4); o process for determining whether a change to a PRA is classified as PRA maintenance or a PRA upgrade (see Appendix C); and o definitions related to NDMs, PRA maintenance, and PRA upgrade (see Glossary); • enhances guidance related to key assumptions and sources of uncertainty (see regulatory position C.3.3.2); • provides a glossary of key terms; and • provides a list of hazards to be considered in the development and use of PRA (see Appendix D). Staff's previous endorsement of ASME/ANS RA-Sa-2009, “Standard for Level 1/Large Early Release Frequency Probabilistic Risk Assessment for Nuclear Power Plant Applications,” in RG 1.200, Revision 2, is not changed by this revision and is reproduced in Appendix A. Background In 1995, the U.S. Nuclear Regulatory Commission (NRC) issued a Policy Statement titled, “Use of Probabilistic Risk Assessment Methods in Nuclear Regulatory Activities; Final Policy Statement” (Ref. 1). This Policy Statement encourages the use of probabilistic risk assessment (PRA) in all regulatory matters and states that, “…the use of PRA technology should be increased to the extent supported by the state-of-the-art in PRA methods and data and in a manner that complements the NRC’s deterministic approach.” Additionally, on July 28, 2000, the staff issued SECY-00-0162, “Addressing PRA Quality in Risk-Informed Activities” (Ref. 25), which describes an approach for addressing PRA quality in risk- informed activities, including identification of the scope and minimal functional attributes of a technically acceptable PRA. Subsequently, on July 13, 2004, the staff issued SECY-04-0118, “Plan for the Implementation of the Commission’s Phased Approach to PRA Quality” (Ref. 26), which