Document: NUREG-0800
Document ID: 7bdf9a80-e0a1-48fe-a048-0d2501e0ff68
Document Type: srp
Title: EMERGENCY DIESEL ENGINE COMBUSTION AIR INTAKE AND EXHAUST
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070573.pdf
Revision Date: 2023-06
Chapter: 9
Section ID: 9.5.8
CFR Part: 
CFR Title: 

Content:
emergency diesel engines. DRAFT Rev. 3 - April 1996 9.5.8-6 3. GDC 5 prohibits the sharing of SSC important to safety among nuclear power units unless it can be demonstrated that such sharing will not significantly impair their ability to perform their safety functions, including in the event of an accident in one unit, an orderly shutdown and cooldown of the remaining unit. The safety function of the EDECAIES is to provide combustion air to the emergency diesel engines under all operating conditions. In order to ensure the availability of emergency ac power to safety- related components, the EDECAIES 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. 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 combustion air intake and exhaust system is integral to the emergency diesel generator system. Regulatory Guide 1.9 provides regulatory positions with regard to emergency diesel engine and combustion air 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. 5. 10 CFR 50.63 requires that each light-water-cooled nuclear