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:
urces would be consistent with other SRs related to data. Clarification COMPARE results and EXPLAIN differences in the initiating event analysis with generic data sources to provide a reasonable check of the results. An example of an acceptable generic data sources is NUREG/CR-6928 [Note (1)]. Footnote (1)(a) to Table 2-2.1- 4(c) The first example makes an assumption that the hourly failure rate is applicable for all operating conditions. Clarification …Thus, fbus at power = 1×10-7/hr * 8760 hrs/yr * 0.90 = 7.9×10-4/reactor year. In the above example, it is assumed the bus failure rate is applicable for at- power conditions. It should be noted that initiating event frequencies may be variable from one operating state to another due to various factors. In such cases, the contribution from events occurring only during at-power conditions should be utilized. IE-D1 thru IE-D3 -------------------- No objection -------------------- DG-1362, Appendix A, Page A-10 Table A-2. Staff Position on ASME/ANS RA-Sa-2009 Part 2, Technical and Peer Review Requirements for At-Power Internal Events Index No Issue Position Resolution 2-2.2 – AS 2-2.2.1 The HLR and associated SRs are written for CDF and not LERF; therefore, references to LERF are not appropriate. Clarification 2-2.2.1 Objectives. The objectives… reflected in the assessment of CDF and LERF is such a way that…. Table 2-2.2-1 -------------------- No objection -------------------- Tables 2-2.2-2(a) thru 2-2.2-4(c) AS-A1 thru AS-A8, AS- A10, AS-A11 -------------------- No objection -------------------- AS-A9 The code requirements for acceptability need to be stated. Clarification Cat II and III: …affect the operability of the mitigating systems. (See SC-B4.) AS-B1 thru AS-B7 -------------------- No objection -------------------- AS-C1 thru AS-C3 -------------------- No objection -------------------- 2-2.3 – SC 2-2.3.1 The HLR and associated SRs are written for CDF and not LERF; therefore, references to LERF are