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:
n system should result in loss of function of both sprinkler and hose standpipe systems in an area protected by such primary and backup systems. (3) As a minimum, the fire suppression system should be capable of delivering water to manual hose stations located within hose reach of areas containing equipment required for safe plant shutdown following the Safe Shutdown Earthquake (SSE). In areas of high seismic activity, the staff will consider on a case-by-case basis the need to design the fire detection and suppres- sion systems to be functional following the SSE. (4) The fire-protection systems should retain their original design capability for (a) natural phenomena of less severity and greater frequency than the most severe natural phenomena (approximately once in 10 years) such as tornadoes, hurricanes, floods, ice storms, or small- intensity earthquakes that are characteristic of the geographic region and (b) potential man- created site-related events such as oil barge collisions or aircraft crashes that have a reasonable probability of occurring at a specific plant site. The effects of lightning strikes should be included in the overall plant fire protection program. (5) The consequences of inadvertent operation of or a crack in a moderate energy line in the fire suppression system should meet the guidelines specified for moderate-energy systems outside containment in Section 3.6.1 of the Standard Review Plan, NUREG-75/087. d. Simultaneous Events (1) Fires need not be postulated to be concurrent with non-fire-related failures in safety systems, other plant accidents, or the most severe natural phenomena. (2) On multiple-reactor sites, unrelated fires need not be postulated to occur simulta- neously in more than one reactor unit. The effects of fires involving facilities shared between units and fires due to man-created site-related events that have a reasonable probability of 1.120-6 occurring and affecting more than one reactor unit (such as an aircraft crash)