Document: NUREG-0800
Document ID: 949ca18d-b0e4-4b54-9ca9-fdb657988111
Document Type: srp
Title: Revision 5 - March 2007
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0706/ML070660170.pdf
Revision Date: 2023-06
Chapter: 7
Section ID: 7
CFR Part: 
CFR Title: 

Content:
ate core cooling instrumentation should provide unambiguous indication of these conditions. It should provide the operator with sufficient information during accident situations to take planned manual actions, and to determine whether safety systems are operating properly. In addition, the instrumentation should also provide sufficient data for the operator to be able to evaluate the potential for core uncovery and gross breach of protective barriers, including the resultant release of radioactivity to the environment. NUREG-0737 provides additional guidance on conformance with this requirement. The evaluation of conformance with this requirement should be addressed in the review of Section 7.5 of the SAR. (i) 10 CFR 50.34(f)(2)(xiv): Addressing [TMI Action Plan Item II.E.4.2] Containment Isolation Systems "Provide containment isolation systems that (A) ensure all non-essential systems are isolated automatically by the containment isolation system; (B) for each non-essential penetration (except instrument lines) have two isolation barriers in series; (C) do not result in reopening of the containment isolation valves on resetting of the isolation signal; (D) utilize a containment set point pressure for initiating containment isolation as low as is compatible with normal operation; and (E) include automatic closing on a high radiation signal for all systems that provide a path to the environs." Applicability - ESFAS - note that item (B) is not included in the scope for the organization responsible for I&C systems. Appendix 7.1-A-7 Revision 5 - March 2007 Review Methods - The containment isolation functions of the ESFAS should be reviewed to confirm that the ESFAS automatically closes each isolation device on each nonessential penetration. Signal diversity should be provided for the containment isolation function. For plants with digital-computer-based ESFAS, signal diversity can be confirmed by review of the licensee/applicant's diversity and defense-in-depth