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:
ion 2, as a means of satisfying the peer review requirements in ASME/ANS RA-Sa-2009 and for the purpose of meeting regulatory position C.2 of this RG. The NRC staff has endorsed ASME/ANS RA-Sa-2009 in Appendix A of this RG with exceptions and clarifications and the Code Case to ASME/ANS RA-Sb-2013 for Seismic PRA in Appendix B of this RG, with exceptions and clarifications. A peer review can be used to demonstrate that the base Level 1 and limited-Level 2, internal and external hazards, at-power, PRA is acceptable for supporting a risk-informed application if the peer review is conducted consistent with the staff’s regulatory position in Appendix A or Appendix B, as applicable, and the guidance in NEI 17-07, Revision 2. Differences between the current version of ASME/ANS RA-Sa-2009, as endorsed by the NRC, and the earlier version (ASME RA-Sb-2005) should be identified and addressed by the licensee in a risk-informed application. In addition, future peer reviews should be performed against the established national consensus PRA standards and peer review guidance, as endorsed in this RG with staff exceptions and clarifications. As described in regulatory positions C.2.2.2.1 and C.2.2.2.2, the Glossary, and Appendix C of this RG, PWROG-19027-NP, Revision 1, provides definitions of terms, requirements and guidance related to the peer review of NDMs, and guidance for determining whether a change to a base PRA is PRA maintenance or a PRA upgrade. The staff reviewed PWROG-19027-NP, Revision 1, and endorses: • specific definitions from Section 2, as included in the Glossary of this RG; • the guidance provided in Section 3 as one acceptable approach for determining whether a change to a PRA model is classified as PRA maintenance or a PRA upgrade, which is consistent with regulatory position C.2.2.2 and Appendix C of this RG, with the following clarification: o The description of Step 2 of the process in Section 3 of PWROG-19027-NP, Revision 1, includes four items. The