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:
LERF PRA Index No Issue Position Resolution 1-6.6.1 The specific SRs addressed in the peer review need to be documented. As written it is not clear whether certain essential items are included in the documentation requirements that are necessary to accomplish the goal of the peer review. Clarification (e) a discussion of the extent to which each PRA Element was reviewed, including a list of SRs that were reviewed Section 1-7 References See global comment on references at start of Table A-1. Appendix 1-A Global The word “significant” is used in many places throughout the Appendix. For example, the term “significant changes in scope or capability” is used to classify a change as a PRA upgrade, rather than a PRA maintenance. The term “significant change in risk insights” is used to indicate when a focused peer review is suggested even for what is nominally classified as a PRA maintenance. While what is meant by the former is clarified in the examples, what constitutes a “significant change in risk insights” needs to be defined and added to the defined terms in Section 1-2. Clarification Add to list of definitions -- Significant change in risk insights: Whether a change is considered significant is dependent on the context in which the insights are used. A change in the risk insights is considered significant when it has the potential to change a decision being made using the PRA. DG-1362, Appendix A, Page A-6 Table A-1. Staff Position on ASME/ANS RA-Sa-2009 Part 1, General Requirements for an At-Power Level 1 and LERF PRA Index No Issue Position Resolution 1-A.3, Examples 1 thru 7, 9, 11-16, 19, 20, 22 thru -------------------- No objection -------------------- 1-A.1, 4th paragraph As written, it could be inferred that a newly developed method would not be considered an upgrade. Clarification . . . “new” should be interpreted as new to the subject PRA even though the methodology in question has been applied in other PRAs and includes newly