Document: NUREG-0800
Document ID: 2b0752f4-9104-408c-b400-d0ec931a3dbf
Document Type: srp
Title: FIRE PROTECTION PROGRAM
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052350030.pdf
Revision Date: 2023-06
Chapter: 9
Section ID: 9.5.1
CFR Part: 
CFR Title: 

Content:
own with fire suppression water without electrical faulting. Manual hose stations and portable hand extinguishers should be provided. Safety-related cable trays of a single division that are separated from redundant divisions by a fire barrier with a minimum rating of 3 hours 9.5.1-34 Rev. 2 - July 1981 and are normally accessible for manual firefighting should be protected from the effects of a potential exposure fire by providing automatic water suppression in the area where such a fire could occur. Automatic area protection, where provided, should consider cable tray arrangements and possible transient combustibles to ensure adequate water coverage for areas that could present an exposure hazard to the cable system. Manual hose standpfpe systems may be relied upon to provide the primary fire suppression (in lieu of automatic water suppression systems) for safety-related cable trays of a single division that are separated from redundant safety divisions by a fire barrier with a minimum rating of 3 hours and are normally acces- sible for manual firefighting if all of the following conditions are met: (a) The number of equivalent* standard 24-inch-wide cable trays (both safety-related and nonsafety-related) in a given fire area is six or less; (b) The cabling does not provide instrumentation, control or power to systems required to achieve and maintain hot shutdown; and (c) Smoke detectors are provided in the area of these cable routings, and continuous line-type heat detectors are provide in the cable trays. Safety-related cable trays that are not accessible for manual fire fighting should be protected by a zoned automatic water system with open-head deluge or open directional spray nozzles arranged so that adequate water coverage is provided for each cable tray. Such cable trays should also be protected from the effects of a potential exposure fire by providing automatic water suppression in the area where such a fire could occur. In other areas where it may not