Document: NRC Regulatory Guide
Document ID: 80776ca5-a83d-4667-9a94-0bffa1befa91
Document Type: regulatory_guide
Title: Fire Protection Guidelines for Nuclear Power Plants (Rev. 1)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML1221/ML12216A013.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.120
CFR Part: 
CFR Title: 

Content:
luding the AFFF deluge system. These systems should comply with the requirements of NFPA 11, NFPA 1lA, and NFPA l1B as applicable. d. Halon Suppression Systems Halon fire extinguishing systems should, as a minimum, comply with the requirements of NFPA 12A and 128, "Halogenated Fire Extinguishing Agent Systems - Nalon 1301 and Halon 1211." Only UL-listed or FM-approved agents should be used. Provisions for locally disarming automatic Halon systems should be key locked and under strict administrative control. Automatic Halon 1.120-16 extinguishing systems should not be disarmed unless controls as described in Regulatory Position C.2.c. are provided. In addition to the guidelines of NFPA 12A and 12B, preventive maintenance and testing of the systems, including check-weighing of the Halon cylinders, should be done at least quarterly. Particular consideration should also be given to: (1) Minimum required Halon concentration, distribution, soak time, and ventilation control; (2) Toxicity of Halon; (3) Toxicity and corrosive characteristics of the thermal decomposition products of Halon; and (4) Location and selection of the activating detectors. e. Carbon Dioxide Suppression Systems Carbon dioxide extinguishing systems should, as a minimum, comply with the requirements of NFPA 12, "Carbon Dioxide Extinguishing Systems." Where automatic carbon dioxide systems are used, they should be equipped with a predischarge alarm system and a discharge delay to permit personnel egress. Provisions for locally disarming automatic carbon dioxide systems should be key locked and under strict administrative control. Automatic carbon dioxide extinguishing systems should not be disarmed unless controls as described in Regulatory Position C.2.c. are provided. Particular consideration should also be given to: (1) Minimum required CO2 concentration, distribution, soak time, and ventilation control; (2) Anoxia and toxicity of CO2 ; (3) Possibility of secondary thermal shock (cooling) damage; (4)