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:
nctional. Sample size and inspection frequency should be determined by the total number of penetrations and observed failure rates. NFPA 25, “Standard for the Inspection, Testing, and Maintenance of Water-Based Fire Protection Systems” (Ref. 67), contains additional guidance. 3. Fire Detection and Suppression 3.1 Fire Detection In general, the fire hazards analysis and regulatory requirements determine the scope of fire detection and suppression in the plant, whereas the applicable industry codes and standards (generally NFPA codes, standards, and recommended practices) determine the design, installation, and testing requirements of the systems and components. The design of fire detection systems should minimize the adverse effects of fires on SSCs important to safety. Automatic fire detection systems should be installed in all areas of the plant that contain or present an exposure fire hazard to SSCs important to safety. These fire detection systems should be capable of operating with or without offsite power. With regard to protection of safe-shutdown systems, Regulatory Positions 5.3.1.1.b and 5.3.1.1.d of this guide state, “In addition, fire detectors and an automatic fire suppression system should be installed in the fire area.” Where automatic fire detection is installed, it should provide complete protection throughout the fire area. For those areas where only partial coverage is installed, the fire hazards analysis should demonstrate the adequacy of the design to provide the necessary protection. The fire detection and alarm system should be designed with the following objectives: a. Detection systems are to be provided for all areas that contain or present a fire exposure to equipment important to safety. b. Fire detection and alarm systems should comply with the requirements of Class A systems, as defined in NFPA 72, “National Fire Alarm Code” (Ref. 68), and Class I circuits, as defined in NFPA 70, “National Electrical Code” (Ref. 69).