Document: NUREG-0800
Document ID: f03d2c71-27a1-41fd-9362-1e62c6142e13
Document Type: srp
Title: Containment Systems and Severe Accidents (Tier 1)
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070653.pdf
Revision Date: 2023-06
Chapter: 14
Section ID: 14.3.11
CFR Part: 
CFR Title: 

Content:
April 1996 - Lighting - emergency control room, remote shutdown panel NOTE:It may be difficult to rationalize its inclusion based on "accomplishing a direct safety function." The basis has to be more defense-in-depth and operating experience and possibly PRA. 4. Lightning protection - general configuration type check. 5. Grounding - configuration type check. For both lightning protection and grounding, it is expected that this will be part of a inspection to check that the features exist. No analyses to demonstrate adequacy need be in ITAAC. 6. Lighting 7. GDC 17 and 18 specified requirements. For example, GDC 17 requires that physically independent circuits be provided from the offsite to the Class 1E distribution system. Also, GDC 17 requires provisions be included to minimize the likelihood of losing all electric power as a result of a coincident loss of more than one power supply. Here is a case where some design description and ITAAC or interface requirements are needed for a "non-Class 1E" area, because of its "importance to safety." 8. Other specific rules and regulations that are applicable to electric systems. For example, the Station Blackout Rule (10 CFR 50.63) is met by an Alternate AC source or a coping analysis, and the appropriate features should be in Tier 1. These are non-Class 1E aspects, but are "important to safety." 9. Regulatory Guides (RGs) which have specific recommendations (all the RG guidance may not need Tier 1 treatment). Here may be an area that Tier 1 treatment captures the design aspect addressed by the RG but the acceptance criteria allows alternate approaches which are then discussed in DCD Tier 2. 10. Operating experience problems of safety significance that have been identified - particularly through EDSFIs, Generic Letters, NRC Bulletins and in some cases Information Notices. For example, degraded voltages have been highlighted. In addition, breaker coordination and short circuit protection have been also highlighted. 11. Policy