Document: NUREG-0800
Document ID: bc7e4c14-0eaa-4591-a506-23d7893f8a00
Document Type: srp
Title: as establishing acceptable guidance for meeting the requirements of this criterion.
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070498.pdf
Revision Date: 2023-06
Chapter: 8
Section ID: 8.3.1
CFR Part: 
CFR Title: 

Content:
rimary reviewer obtains and uses such input as required to ensure that this review procedure is complete. 1. System Redundancy Requirements General Design Criteria 33, 34, 35, 38, 41, and 44 set forth requirements with regard to the safety systems that must be supplied by the ac onsite power system. Also, these criteria state that safety system redundancy should be such that, for onsite power system operation (assuming offsite power is not available), the system safety function can be accomplished assuming a single failure. The acceptability of the onsite power system with regard to redundancy is based on conformance to the same degree of redundancy of safety-related components and systems required by these General Design Criteria. IEEE Std 603, as endorsed by Regulatory Guide 1.153, provides criteria used to evaluate all aspects of the electrical portions of safety-related systems and the onsite power system, including criteria addressing redundancy. The descriptive information — including electrical single-line 85 diagrams (CP and OL stage), functional P&IDs (CP and OL stage), and electrical schematics (OL stage) — is reviewed to verify that this redundancy is reflected in 86 the standby power system with regard to both power sources and associated 8.3.1-15 DRAFT Rev. 3 - April 1996 distribution systems. Also, it is verified in coordination with other branches that redundant safety loads are distributed between redundant distribution systems and that the instrumentation and control devices for the Class 1E loads and power system are supplied from the related redundant distribution systems. 2. Conformance with the Single Failure Criterion As required by General Design CriterionGDC 17, the onsite ac power system must be capable of performing its safety function assuming a single failure. In evaluating the adequacy of this system in meeting the single failure criterion, both electrical and physical separation of redundant power sources and distribution systems,