Document: NUREG-0800
Document ID: 7e9d3620-7a94-488e-b2d5-992282113080
Document Type: srp
Title: NUREG408OO
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052350480.pdf
Revision Date: 2023-06
Chapter: 7
Section ID: 7
CFR Part: 
CFR Title: 

Content:
er requirements of IEEE Std 279. A number of designs have been proposed and accepted which reliably and simply satisfy this requirement. During the review of some applications, however, certain design deficiencies have been found. The purpose of this position is to provide additional guidance on the application of Section 4.15 of IEEE Std 279. B. BRANCH TECHNICAL POSITION 1. If more restrictive safety trip points are required for operation with a reactor coolant pump out of service, and if operation with a reactor coolant pump out of service is of sufficient likelihood to be a planned mode of operation, the change to the more restrictive trip points should be accomplished automatically. 2. Plants with designs not in accordance with the above should have included in the plant technical specifications a requirement that the reactor be shut down prior to changing the set points manually. C. REFERENCES 1. Millstone-3 Safety Evaluation Report, September 24, 1973. 2. Beaver Valley-2 Safety Evaluation Report, October 10, 1973. 3. IEEE Std 279, "Criteria for Protection Systems for Nuclear Power Generating Stations." 7A-9 Rev. 2 - July 1981 BRANCH TECHNICAL POSITION ICSB 13 DESIGN CRITERIA FOR AUXILIARY FEEDWATER SYSTEMS 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. It is the purpose of this Branch Technical Position to provide guidance and to establish uniform requirements for acceptable designs of auxiliary feedwater systems. B. BRANCH TECHNICAL POSITION The auxiliary feedwater system should be capable