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:
propriate fire protection, and control use of specific combustibles (e.g., wood) in plant areas important to safety. DG-1359, Page 40 2.1.1 Transient Fire Hazards Bulk storage of combustible materials should be prohibited inside or adjacent to buildings or systems important to safety during all modes of plant operation. Procedures should limit and govern the handling of transient fire hazards, such as combustible and flammable liquids, wood and plastic products, high-efficiency particulate air (HEPA) and charcoal filters, dry ion exchange resins, or other combustible materials in buildings containing systems or equipment important to safety during all phases of operation, particularly during maintenance, modification, or refueling operations. Licensees should control and provide suitable protection against transient fire hazards that cannot be eliminated. Specific controls and protective measures include the following: a. Unused ion exchange resins should not be stored in areas that contain or expose equipment important to safety. b. Hazardous chemicals should not be stored in areas that contain or expose equipment important to safety. c. Use of wood inside buildings containing systems or equipment important to safety should be permitted only when suitable noncombustible substitutes are not available. All wood smaller than 152 millimeters (mm) ×152 mm (6 inches (in.) × 6 in.) used in plant areas important to safety during maintenance, modification, or refueling operations (such as lay down blocks or scaffolding) should be treated with a flame retardant. (For guidance, see NFPA 703, “Standard for Fire-Retardant Treated Wood and Fire-Retardant Coatings for Building Materials” (Ref. 56).) Wood should be allowed into plant areas important to safety only when it is to be used immediately. d. The use of plastic materials should be minimized. Halogenated plastics, such as polyvinyl chloride and neoprene, should be used only when substitute noncombustible materials