Document: NUREG-0800
Document ID: f673d9c7-5410-4f11-8c45-1935b546a77f
Document Type: srp
Title: EMERGENCY DIESEL ENGINE COOLING WATER SYSTEM
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070570.pdf
Revision Date: 2023-06
Chapter: 9
Section ID: 9.5.5
CFR Part: 
CFR Title: 

Content:
fsite power is not available. Typically, the emergency diesel generator system is the onsite electric power system relied upon when offsite power is unavailable. The diesel engine cooling water system is integral to the emergency diesel generator system and serves to transfer heat away from diesel engine components to the ultimate heat sink. Meeting GDC 44 provides assurance that important safety functions can be accomplished under normal operating and accident conditions. 7. GDC 45 establishes requirements regarding the design of cooling water systems to permit appropriate periodic inspection of important components, such as heat exchangers and piping, to assure the integrity and capability of the system. The EDECWS provides engine cooling for the emergency diesel generator which in turn provides emergency power to plant SSC important to safety. Periodic inspections/tests of the EDECWS provide assurance that the system will function as designed to support operation of the onsite emergency power supply. 8. GDC 46 establishes requirements regarding the design of cooling water systems to permit appropriate periodic pressure and functional testing under conditions as close to design as practical. The EDECWS provides engine cooling for the emergency diesel generators which in turn provide emergency power to plant SSC important to safety. Periodic inspections/tests of the EDECWS provide assurance that the system will function as designed to support operation of the onsite emergency power supply. 9. 10 CFR 50.63 requires that each light-water-cooled nuclear power plant be able to withstand and recover from a station blackout (i.e., loss of the offsite electric power system concurrent with reactor trip and unavailability of the onsite emergency ac electric power system). Paragraph (a)(2) of 50.63 establishes the conditions under which provision of an alternate ac (AAC) power source will constitute acceptable capability to withstand station blackout. Regulatory Guide 1.155