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:
ded to ensure that the fire doors will protect the opening as required in case of fire: a. Fire doors should be kept closed and electrically supervised at a continuously manned location. b. Fire doors should be locked closed and inspected weekly to verify that the doors are in the closed position. c. Fire doors should be provided with automatic hold-open and release mechanisms and inspected daily to verify that doorways are free of obstructions. DG-1359, Page 69 d. Fire doors should be kept closed and inspected daily to verify that they are in the closed position. Areas protected by automatic total-flooding gas suppression systems should have electrically supervised self-closing fire doors or should satisfy option (a) above. NFPA 80, “Standard for Fire Doors and Other Opening Protectives” (Ref. 109), provides additional guidance for fire doors. 4.2.1.3 Fire Dampers Building design should ensure that ventilation openings are properly protected. These openings should be protected with fire dampers that have been fire tested. In addition, the construction and installation techniques for ventilation openings through fire barriers should be qualified by fire endurance tests. For ventilation ducts that penetrate or terminate at a fire wall, guidance in NFPA 90A indicates that ventilation fire dampers should be installed within the fire wall penetration for barriers with a fire rating greater than or equal to 2 hours. NFPA 90A requires that fire dampers be installed in all air transfer openings within a rated wall. Until recently, the only industry standard governing the design, fabrication, and testing of fire dampers was UL Standard 555, “Fire Dampers” (Ref. 110). That standard does not evaluate whether fire dampers will close under airflow conditions. Therefore, the UL fire damper rating indicates only whether a fire damper in the closed position will maintain its integrity under fire conditions for a specific time period. Fire damper testing methods that do not