Document: NUREG-0800
Document ID: 05a851a6-07ff-41b4-8528-a032ba433e04
Document Type: srp
Title: FIRE PROTECTION PROGRAM
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0327/ML032740044.pdf
Revision Date: 2023-06
Chapter: 9
Section ID: 9.5.1
CFR Part: 
CFR Title: 

Content:
tions and to provide positive (manual) control of safe shutdown equipment. Others have procedures that may cause a SBO condition to be created as a result of fire effects (e.g., procedures that direct operators to manually trip the credited safe shutdown emergency diesel generator (EDG) in the event of fire damage to circuits of vital EDG support systems). The acceptability of safe shutdown procedures that voluntarily enter, or otherwise create, an SBO condition is determined on a case-by-case basis. The ability to cope with SBO as part of the post-fire safe shutdown methodology is dependent on such issues as time-line logic; assumptions and bases for plant and operator response relative to component realignment; the ability of plant operators to monitor and control plant parameters and align plant components before, during, and after SBO control room evacuation and abandonment; and the practicality and reliability of EDG start and load (and restart, if applicable) under post-fire safe shutdown SBO conditions. The relative risk of self- imposed SBO may greatly exceed the actual risk posed by the fire and should be given appropriate consideration when evaluating the plant safe shutdown design and procedures. Applications for advanced reactor designs may not rely on SBO to mitigate potential fire damage to safe shutdown systems or associated circuits. 2.7 Shutdown/Low Power Operations Revision 4 - October 2003 19 Safe shutdown requirements and objectives are focused on achieving shutdown conditions for fires occurring during normal at-power operations. During shutdown operations (i.e., maintenance or refueling outages) fire conditions can change significantly as a result of work activities. In addition, redundant systems important to safety may not be available as allowed by plant Technical Specifications and plant procedures. The fire protection program should be reviewed to verify that fire protection systems, features, and procedures will minimize the potential for