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:
REVIEW RESPONSIBILITIES Primary - Auxiliary Systems Branch (ASB) Secondary - None I. AREAS OF REVIEW The auxiliary feedwater system (AFWS) normally operates during startup, hot standby and shutdown as. the feedwater system for pressurized water reactor (PWR) plants. In conjunction with a seismic Category I water source, it also functions as an emergency system for the removal of heat from the primary system when the main feedwater system is not available for emergency conditions including small LOCA cases. The AFWS operates over a time period sufficient either to hold the plant at hot standby for several hours or to cool down the primary system, at a rate not to exceed limits specified in technical specifications, to temperature and pressure levels at which the low pressure decay heat removal system can operate. The design of the AFWS should meet the requirements of General Design Criteria 2, 4, 5, 19, 34, 44, 45 and 46. The ASB reviews the AFWS from the condensate storage tank (normal operation), or the seismic Category I water supply including valving and cross-connects (emergency operation), to the connections with the steam generators, which are made either through a connection to the main feedwater piping or through separate auxiliary feedwater piping connected directly to the steam generators. All inter-connections and cross-connections are included in the review. The review also includes AFWS components, e.g., pumps, valves, and piping, with respect to their functional performance as affected by adverse environ- mental occurrences, abnormal operational requirements, and off-normal conditions, e.g., small breaks in the primary system or the loss of offsite power. The system is reviewed to determine that a single malfunction, a failure of a component, or the loss of a cooling source does not reduce the safety-related Rev. 2 - July 1981 USNRC STANDARD REVIEW PLAN Standard review plans are prepared for the guidance of the Office of Nuclear Reactor Regulation