Document: NRC Regulatory Guide
Document ID: 81395c8e-49df-441c-b98a-8ae655d174db
Document Type: regulatory_guide
Title: Emergency Planning and Preparedness for Nuclear Power Reactors (Rev. 7)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML2401/ML24019A202.pdf
Revision Date: 2025-03
Chapter: 
Section ID: RG-1.101
CFR Part: 
CFR Title: 

Content:
ary and backup ANS methods should ensure that any common- mode failures are evaluated, if applicable, to ensure that reasonable assurance that adequate protective measures can and will be taken in the event of a radiological emergency is maintained regardless of this common-mode failure possibility. 4.4.1 Any common-mode failures identified should be adequately identified and evaluated by satisfying the following: 4.4.1.1 These common-mode failures should be appropriately risk-informed. 4.4.1.2 The evaluation should be documented. 4.4.1.3 For example, if both the primary and backup systems utilize a common system or component for activation, the submittal should include an evaluation of how the potential common failure would be addressed, how the ANS is adequately risk-informed and performance-based, and how reasonable assurance is maintained (i.e., reliability of diverse methods, defense-in-depth, etc.). Note that the reliability of FEMA’s Integrated Public Alert and Warning System (IPAWS) is primarily based upon the multiple methods of public alert and notification that would be activated simultaneously using the IPAWS architecture versus relying on one method (e.g., fixed sirens) and that each of these separate ANS methods can be individually activated if, for whatever reason, the IPAWS architecture fails to activate ANS as intended. 4.4.1.4 The evaluation should be included in the ANS Evaluation Report. Reference: Information Notice (IN) 2024-02, “Impact on Licensee Emergency Plans From Changes Made By Offsite Response Organizations to Alert and Notification System,” dated March 25, 2024 (Ref. 34), for additional information. NEI White Paper, “Implementing a 24-Month Frequency for Emergency Preparedness Program Reviews,” Revision 0, and Staff Requirements Memorandum (SRM)-SECY-23-0010 5. The NRC staff previously endorsed the NEI white paper, “Implementing a 24-Month Frequency for Emergency Preparedness Program Reviews,” Revision 0, in Revision 6 of