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:
be experienced when the diesel generator set is required to operate continuously at the maximum rated power output. gf . The combustion air intake system shall be provided with a means of reducing 37 airborne particulate material over the entire time period that emergency power is required assuming the maximum airborne particulate concentration at the combustion air intake. 9.5.8-5 DRAFT Rev. 3 - April 1996 hg . Suitable design precautions have been taken to preclude degradation of the diesel 38 engine power output due to exhaust gases and other dilutents that could reduce 39 the oxygen content below acceptable levels. Plants that have emergency ac sources in excess of minimum redundancy requirements for loss-of-offsite-power conditions may use one of the existing emergency sources as an alternate ac (AAC) power source for the purposes of coping with a station blackout, provided it meets the applicable criteria for an AAC source. For a plant relying on an emergency diesel engine as an AAC power source, the design of the combustion air intake and exhaust system for that engine is acceptable if it meets 10 CFR Part 50.63, "Loss of All Alternating Current Power," paragraph (a)(2), and Regulatory Guide 1.155, Position C.3.40 Technical Rationale:41 The technical rationale for application of the above acceptance criteria to the emergency diesel engine combustion air intake and exhaust system is discussed in the following paragraphs. 1. GDC 2 requires that SSC important to safety be designed to withstand the effects of natural phenomena such as earthquakes, tornadoes, hurricanes, floods, tsunami, and seiches without loss of capability to perform the safety function. Regulatory Guide 1.117 provides the methods acceptable to the staff for tornado design classification of structures, systems and components important to safety. The safety function of the EDECAIES is to supply quality combustion air to the emergency diesel engine. A quality combustion air supply is necessary