Document: NUREG-0800
Document ID: 5ba2907e-cf47-4a3b-b320-616735faa4cf
Document Type: srp
Title: AUXILIARY FEEDWATER SYSTEM (PWR)
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052350095.pdf
Revision Date: 2023-06
Chapter: 10
Section ID: 10.4.9
CFR Part: 
CFR Title: 

Content:
ets these requirements. e. The system is designed with adequate redundancy to accommodate a single active component failure without loss of function. This includes redundant piping and valves from the condensate storage tank (or other primary source) to the AFW pump suctions. f. Diversity in pump motive power sources and essential instrumentation and control power sources has been provided. The diverse system including pump(s), controls and valves should be independent of offsite and onsite AC power sources in accordance with the guidelines of Branch Technical Position ASB 10-1. g. The system is designed with adequate instrumentation to automatically initiate auxiliary feedwater flow to the steam generators upon receipt of an actuation signal. The initiation signal should start all auxiliary feedwater pumps and supporting systems, align the auxiliary feedwater sources, and open flow paths from the auxiliary feedwater pumps to the steam generator(s). The system is also designed with the capability to manually initiate the necessary protective actions. The AFWS is designed with redundant instrumenta- tion so that the system will automatically limit (may be flow limiting orifice rather than instrumentation) or terminate auxiliary feedwater flow to a depressurized steam generator, and to assure that the minimum required flow is directed to the intact steam generator(s). The electrical portion of this review is performed by ICSB as indicated in subsection I of this SRP section. If a flow limiter is used then it must be demonstrated that sufficient flow still goes to the intact steam generator and containment design pressure is not exceeded by the AFW flow to the depressurized generator. j. The AFWS is designed with sufficient flow capacity so that the system can remove residual heat over the entire range of reactor operation and cool the plant to the decay heat removal system cut-in temperature. This review is performed by RSB upon request as indicated in subsection I of