Document: NUREG-0800
Document ID: 2cb61281-91f4-400a-8eda-41e187e51d77
Document Type: srp
Title: AUXILIARY FEEDWATER SYSTEM (PWR)
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0705/ML070570007.pdf
Revision Date: 2023-06
Chapter: 10
Section ID: 10.4.9
CFR Part: 
CFR Title: 

Content:
rcent capacity pump should have sufficient capacity for decay heat removal following any accident or transient although cool down to RHR cut in temperature may take longer than design. This capability should also be met for conditions involving a small-break area LOCA or a pipe break outside containment. 1. The SAR is reviewed to determine that the system description and piping and instrumentation diagrams (P&IDs) identify the AFWS equipment and arrangement that is used for normal operation and for safe plant shutdown (essential) operation. The system P&IDs, layout drawings, and component descriptions and characteristics are then reviewed to verify that: A. Minimum performance requirements are sufficient for the various AFWS functions. B. Essential AFWS portions can be isolated from nonessential portions, so that system performance is not impaired by a nonessential component failure. C. Component and system descriptions in the SAR include appropriate seismic and quality group classifications, and the P&IDs indicate any points of change in piping quality group classification. D. Design provisions have been made that permit appropriate in service inspection and functional testing of system components important to safety. A testing and inspection program described in the SAR and system drawings showing the necessary recirculation loops around pumps or isolation valves as may be required by this program are acceptable in satisfying this provision. E. Design provisions have been made that ensure detection and mitigation of steam binding of the AFWS pumps due to back-leakage from the main feedwater system (MFWS) through isolation valves between the AFWS and the MFWS. This issue is described in IE Bulletin 85-01, “Steam Binding of Auxiliary Feedwater Pumps,” October 29, 1985. F. Design provisions have been incorporated to provide proper minimum flow for pump cooling under all flow conditions, regardless of the water source (condensate storage facility or alternate