Document: NRC Regulatory Guide
Document ID: 8e45dce1-e1e7-4415-b1dd-7e2a610e545b
Document Type: regulatory_guide
Title: Fire Protection for Nuclear Power Plants (Rev. 4)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML2023/ML20231A835.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.189
CFR Part: 
CFR Title: 

Content:
t require an exemption request, except for proposed modifications that would alter previously approved features used to satisfy NRC requirements. DG-1359, Page 36 Plant-specific conditions may prevent compliance with one or more of the provisions specified in Appendix R. In such a case, the licensee should demonstrate, by means of a detailed fire hazards analysis, that the existing protection, or the existing protection in conjunction with proposed modifications, will provide a level of safety equivalent to the technical requirements of Appendix R. When the fire hazards analysis (Regulatory Position 1.2 of this guide) shows that an alternative approach (i.e., an approach different from a specified requirement, such as the use of a 1-hour fire-rated barrier where a 3-hour barrier is specified) can provide adequate fire safety, licensees required to meet Appendix R may request NRC approval of an exemption from its technical requirements. Any exemption request should include a sound technical basis clearly demonstrating that the fire protection defense-in-depth philosophy is appropriately maintained and that the exemption is technically justified. As part of its evaluation, the licensee should provide a sound technical justification if it does not propose to install or improve the automatic suppression or detection capabilities in the area of concern or if it does not intend to implement other more restrictive fire prevention, detection, or suppression measures. Generally, the staff will accept an alternative fire protection configuration on the basis of a detailed fire hazards analysis if the following conditions are met: a. The alternative configuration ensures that one success path necessary to achieve hot shutdown from either the control room or emergency control stations is free of fire damage. b. The alternative configuration ensures that fire damage to equipment necessary to achieve cold shutdown is limited and can be repaired within a reasonable time (minor