Document: NUREG-0800
Document ID: de7ae6d6-3745-486a-a2db-b3d5d2ce1009
Document Type: srp
Title: Draft Revision 6 – August 2015
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1515/ML15159A672.pdf
Revision Date: 2023-06
Chapter: 7
Section ID: 7
CFR Part: 
CFR Title: 

Content:
latory Commission, Washington, DC 20555, Attention: Reproduction and Distribution Services Section, by fax to (301) 415-2289; or by email to DISTRIBUTION@nrc.gov. Electronic copies of this section are available through the NRC’s public Web site at http://www.nrc.gov/reading-rm/doc-collections/nuregs/staff/sr0800/, or in the NRC’s Agencywide Documents Access and Management System (ADAMS), at http://www.nrc.gov/reading-rm/adams.html, under ADAMS Accession No. ML15159A672. NUREG-0800 U.S. NUCLEAR REGULATORY COMMISSION STANDARD REVIEW PLAN BRANCH TECHNICAL POSITION 7-4 GUIDANCE ON DESIGN CRITERIA FOR AUXILIARY FEEDWATER SYSTEMS REVIEW RESPONSIBILITIES Primary - Organization responsible for the review of instrumentation and controls Secondary - None A. Background The function of the auxiliary feedwater system in pressurized water reactors is to provide an emergency source of feedwater supply to the steam generators. It is required to ensure safe shutdown in the event of a main turbine trip with loss of offsite power. The system is also started on a safety injection signal. Feedwater is pumped to each steam generator through normally open control valves. It was found that in some plant designs the auxiliary feedwater system did not meet the single failure criterion. Title 10 of the Code of Federal Regulations (10 CFR) 50.34(f)(2)(xii) requires automatic and manual auxiliary feedwater initiation. The purpose of this branch technical position is to provide guidance related to acceptable designs of auxiliary feedwater systems. BTP 7-4-2 Draft Revision - August 2015 B. Branch Technical Position The auxiliary feedwater system should be capable of satisfying the system functional requirements after a postulated break in the auxiliary feedwater piping inside containment together with a single electrical failure. The basis for the position is that an auxiliary feedwater piping break would result in tripping the unit and, in turn, might cause loss of offsite power. Standard