Document: NUREG-0800
Document ID: 59c7531b-4cb1-436b-af66-a05bf36ba24f
Document Type: srp
Title: SAFE SHUTDOWN SYSTEMS
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1515/ML15159B122.pdf
Revision Date: 2023-06
Chapter: 7
Section ID: 7.4
CFR Part: 
CFR Title: 

Content:
safe shutdown. 7.4-7 Draft Revision 6 – August 2015 temperature, emergency or isolation condenser level indication for tanks involved in shutdown, and shutdown system diagnostic instrumentation. The remote shutdown capability should be capable of accommodating expected plant response following a reactor trip, including protective system actions that could occur as a result of plant cooldown. For example, in the cooldown of a PWR, reactor cooling system pressure will eventually drop below the safety- injection initiation setpoint. Because the control room is not available, it may be impossible to block this trip. Therefore, the remote shutdown capability must be able to accommodate this condition. Access to remote shutdown stations should be under strict administrative controls. The equipment in the remote shutdown stations should be designed to the same standards as the corresponding equipment in the main control room. Remote shutdown station-control transfer devices should be located remote from the main control room and their use should initiate an alarm in the control room. The location should be consistent with the procedures for remote, alternative, and dedicated shutdown, as appropriate. Where the control functions are transferred between the control room and the remote shutdown station, the design should maintain parameter indications such that the operators at the control room and the remote shutdown station both have access to the same parameters that are being relied upon. E. Safe shutdown - System conformance to the single-failure criterion on a system basis and operability from onsite and offsite electrical power as required by General Design Criteria 34, 35, and 38. Safe shutdown systems that are safety systems according to the definition of IEEE Std 603-1991 should fulfill the requirements of that standard. The following topics are recommended for review emphasis with respect to IEEE Std 603- 1991: - Meet the single-failure criterion - See SRP