Document: NUREG-0800
Document ID: 853719df-a6ea-408b-8d43-5956155abc38
Document Type: srp
Title: and 8.3.2.
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1007/ML100740246.pdf
Revision Date: 2023-06
Chapter: 8
Section ID: 8.3.1
CFR Part: 
CFR Title: 

Content:
operator action, following a loss of both onsite and offsite ac power sources. Consequently, passive reactor designs are not required to meet the requirements of GDCs 33, 34, 35, 38, 41, and 44 for 72 hours. Meeting the requirements of these criteria as encompassed by GDC 17 provides assurance that required electric power can be provided for all facility operating modes, including transients and design basis accidents so that the safety functions required in these criteria may be performed, even in the event of any single failure. 7. Compliance with 10 CFR 50.63 requires that each light-water-cooled nuclear power plant be able to withstand or cope with, and recover from, an SBO. As required by 10 CFR 50.63, electrical systems that are necessary support systems for SBO must be 8.2-14 Revision 5 - May 2010 of sufficient capability and capacity to ensure that core cooling and appropriate containment integrity are maintained in the event of an SBO. An acceptable means of complying with 10 CFR 50.63 requirements involves the provision of an AAC source (as defined in 10 CFR 50.2) of sufficient capacity, capability, and reliability for operation of all systems required for coping with SBO and for the time required to bring and maintain the plant in safe shutdown that will be available on a sufficiently timely basis. 10 CFR 50.63 also requires (through citation of the definition of AAC source in 10 CFR 50.2) minimum potential for common mode failure (i.e., acceptable independence) between any AAC power source used for SBO and the offsite power system or onsite power sources. Electrical ties between these systems, as well as the physical arrangement of their interface equipment, must not prevent the use of any AAC power source during loss of the offsite power system and/or onsite power sources. It is also important that provisions for an AAC source will not adversely affect performance of offsite or onsite power system functions. AAC power sources located at or near the