Document: NUREG-0800
Document ID: 4139e3ab-3087-44d3-8f66-193711d2480a
Document Type: srp
Title: EMERGENCY DIESEL ENGINE STARTING SYSTEM
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052350041.pdf
Revision Date: 2023-06
Chapter: 9
Section ID: 9.5.6
CFR Part: 
CFR Title: 

Content:
r the safe shutdown of the reactor or necessary to mitigate the consequences of an accident are designed to seismic Category I and Quality Group C. The staff concludes that the design of the emergency diesel engine starting system is acceptable and meets the requirements of GDC 2, 4, 5, and 17. This conclusion is based on the following: 1. The applicant met the requirements of GOC 2, "Design Bases for Protection Against Natural Phenomena," with respect to the ability of structures housing the EDESS and the system itself 9.5.6-5 Rev. 2 - July 1981 to withstand the effects of natural phenomena such as earth- quakes, tornadoes, hurricanes, and floods, and GDC 4, "Environmental and Missile Design Bases," with respect to structures housing the system and the system itself being capable of withstanding the effects of externally and internally generated missiles, pipe whip, and jet impingement forces associated with pipe breaks. The EDESS is housed in a seismic Category I.structure which provides protection from the effects of tornado, tornado missiles, turbine missiles, and floods. This meets the positions of Regulatory Guides 1.115, "Protec- tion Against Low-Trajectory Turbine Missiles," Position C.1, and 1.117, "Tornado Design Classification," Appendix Position 13. 2. The applicant has met the requirements of GDC 5, "Sharing of Structures, Systems and Components," with respect to capability of shared systems and components important to safety. to perform required safety functions. Each unit of the plant has its own emergency diesel generators, whose EDESS is not shared between the diesel generators. 3. The applicant has met the requirements of GDC 17, "Electric Power Systems," with respect to the capability of the air starting system to meet independence and redundancy criteria. Each EDESS is independent and physically separated from the other system serving the redundant diesel generator. A single failure in any one of the systems will affect only the asso- ciated