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:
e remaining unit. The safety function of the EDECWS is to provide cooling water to the EDE following an engine start signal. In order to ensure the availability of emergency ac power to safety-related components, the EDECWS must be designed to perform this safety function in each unit regardless of events, failures, and conditions in the other unit(s). Compliance with GDC 5 provides assurance that equipment failures and events occurring in one unit of the site will not propagate to other units of the site. 9.5.5-7 DRAFT Rev. 3 - April 1996 4. GDC 17, in relevant part, requires provision of an onsite electric power system to permit the functioning of structures, systems and components important to safety. GDC 17 requirements include that the onsite electric power system have sufficient independence and redundancy to perform their safety functions assuming a single failure. Typically, the emergency diesel generator system is the onsite electric power system relied upon to meet these requirements. The diesel engine cooling water system is integral to the emergency diesel generator system. Regulatory Guide 1.9 provides regulatory positions with regard to EDE and cooling water system design criteria and features applicable to GDC 17 compliance. Meeting the GDC 17 requirements provides assurance that electric power will be available for systems necessary to: 1) prevent fuel damage in the event of anticipated operational occurrences; and 2) maintain core cooling and containment integrity in the event of postulated accidents. 6. GDC 44 requires a cooling system to transfer heat from SSC important to safety to an ultimate heat sink. Requirements include suitable redundancy, interconnections, leak detection and isolation capabilities to assure onsite power system operation if offsite 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