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:
equent cold shutdown since the design meets the requirement of Branch Technical Position RSB 5-1 which requires the capability to bring primary plant temperature to the RHR cut-in point following four hours at hot standby from the control room using only safety grade equipment and assuming any single active failure. 5. The system design meets the requirements of Genral Design Criteria 34 and 44 since it has the capability to transfer heat loads, including decay heat from the reactor, during normal operating and accident conditions assuming any single active failure. The system has suit- able redundancy such that it can withstand a pipe break and single active failure and still perform its safety function. The system deign also has sufficient diversity such that it meets the require- ments of Branch Technical Position ASB 10-1. In meeting these General Design Criteria the applicant has also met the generic recommendations identified in NUREGS-0611 and -0635 and has performed a reliability analysis in accordance with NUREG-0737, item II.E.1.1. The results of the reliability analyses were acceptable since it was shown that the AFWS has an unreliability in the range of 10-4 to 10-5 per demand. 6. The pumps, valves, heat exchangers and piping of the system, to the extent practicable, are designed and located to facilitate periodic inspection as required by General Design Criterion 45. This is accomplished by providing adequate accessability to conduct the required examinations. 7. To meet the requirements of General Design Criterion 46, the auxiliary feedwater system is designed to include the capability for testing through the full operational sequence that brings the system into operation for reactor shutdown and for loss-of-coolant accidents, including operation of applicable portions of the protection system and the transfer between normal and emergency buses. V. IMPLEMENTATION The following is intended to provide guidance to applicants and licensees regarding the