Document: NUREG-0800
Document ID: 71224475-ca63-4c09-acc1-c682d58112dd
Document Type: srp
Title: Revision 5 - March 2007
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0705/ML070550082.pdf
Revision Date: 2023-06
Chapter: 7
Section ID: 7
CFR Part: 
CFR Title: 

Content:
ormed passively by opening the discharge check valve when RCS pressure is lower than the tank pressure. Therefore, Category 3 instrumentation is an acceptable alternative to Category 2 if there are no operator actions that depend on use of this instrumentation for accident mitigation. Accumulator isolation valve position Category Category 3 position indication is acceptable if the accumulator isolation valves are locked-open, motor-operated valves (i.e., power to the motor operators is disabled during normal operation) and cannot change position during an accident. Pressurizer heater status Indication At a minimum, status indication should be provided for pressurizer heaters governed by the technical specification (i.e., heaters required to be served by emergency power). Quench tank temperature and pressure Range Pressure relief of the tank via rupture disk limits the temperature of the tank contents to saturated steam conditions (less than 750°F). Therefore, it is acceptable if the upper-range value includes (with adequate margin) the saturation temperature corresponding to the tank rupture disk relief pressure (e.g., a rupture disk relief pressure of 100 psig corresponds to 328°F saturation temperature). Likewise, an upper-range value less than the design pressure of the tank is acceptable if the upper-range value covers (with adequate margin) the rupture disk relief pressure. Steam generator level (wide-range) Redundancy For the wide-range level, two-loop plants should have two channels of instrumentation per loop, but three- and four-loop plants may have one channel of instrumentation per loop Steam generator pressure Redundancy If steam generator pressure is identified as a Type A variable, two-loop plants should have two channels of instrumentation per loop, but three- and four-loop plants may have one channel of instrumentation per loop. Containment atmosphere temperature • Category • Direct measurement Category 3 instrumentation is an acceptable