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:
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 NRC staff considers the first item to be an example of when a state- of-practice method is implemented in a new context whereupon the change to the PRA would be considered a PRA upgrade. However, the last three of the four items are not considered to be examples of when a state-of-practice method is implemented in a new context, because DG-1362, Page 46 they could represent cases where an NDM is being used without being subjected to the NDM technical adequacy assessment peer review.; • the recommended Section 1-7, “Newly Developed Methods” for the ASME/ANS Level 1/LERF PRA standard as documented in Section 4, which is consistent with regulatory position C.2.2.2.2 of this RG; • the recommended requirements in Section 5.1, which are consistent with regulatory position C.2.2.2.1 of this RG, with the following clarification: o PWROG-19027-NP, Revision 1, states that the extent of a focused-scope peer review includes all supporting requirements (SR) under an HLR with an SR that received a peer review Finding. However, the staff finds that, for a focused-scope peer review, all the applicable SRs under any HLR should be included in the scope of the focused-scope peer review for any HLR with one or more SRs that received a Finding from the prior peer review; • the features described in Section 5.2 that are to be added to a peer review report of a plant PRA that uses NDMs and the public availability of NDM peer review reports; and • the potential outcomes of a peer review of an NDM described in Section 5.3 with respect to whether an NDM is able to support a PRA, which meets regulatory position C.2.2.2.2 of this RG. NEI 17-07, Revision 2, provides guidance on peer review for the acceptability of an NDM and peer review for the implementation of an NDM in a PRA and