Document: NUREG-0800
Document ID: 010ad62f-cd7b-4f06-9f81-a781faf5701b
Document Type: srp
Title: ENGINEERED SAFETY FEATURE VENTILATION SYSTEM
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070560.pdf
Revision Date: 2023-06
Chapter: 9
Section ID: 9.4.5
CFR Part: 
CFR Title: 

Content:
ceptable alternate ac source is provided) or coping with a station blackout event is required. The analysis should address, as appropriate, the potential failures of equipment/systems during the event (e.g., loss of or degraded operability of HVAC systems, including the ESFVS, as appropriate), the expected environmental conditions associated with the event, the operability and reliability of equipment necessary to cope with the event under the expected environmental conditions, and the habitability of plant areas requiring operator access during the event and associated recovery period. Acceptance is based on meeting the applicable guidance provided in Regulatory Guide 1.155 including position C.3.2.4.50 Technical Rationale51 The technical rationale for application of the above acceptance criteria to the ESFVS is discussed in the following paragraphs:52 1. Compliance with GDC 2, as related to the system being capable of withstanding the effects of earthquakes, requires that structures, systems, and components important to safety be designed to withstand the effects of a design basis earthquake without loss of capability to perform their safety functions. 9.4.5-7 DRAFT Rev. 3 - April 1996 The function of the ESFVS is to provide a suitable and controlled operating environment for engineered safety feature components during normal operation, during adverse environmental occurrences, and during and subsequent to postulated accidents, including loss of offsite power. GDC 2 is imposed to ensure that engineered safety features will remain functional during and after a design basis earthquake. Meeting this requirement provides assurance that engineered safety features will operate as designed, thus providing protection against loss of core cooling and/or loss of containment integrity.53 2. Compliance with GDC 4 requires that structures, systems, and components important to safety be designed to accommodate the effects of, and be compatible with, environmental conditions