Document: NUREG-0800
Document ID: 4ae4fdd9-3c00-4bbd-8ed8-caac69daf3a5
Document Type: srp
Title: describes the general procedures to be followed in reviewing any instrumentation and control
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0525/ML052500507.pdf
Revision Date: 2023-06
Chapter: 7
Section ID: 7.1
CFR Part: 
CFR Title: 

Content:
system. This part of section 7.6 highlights specific topics that should be emphasized in the interlock systems review. The review should include an evaluation of the interlock system design against the guidance of ANSI/IEEE Std 279, or Reg. Guide 1.153, "Criteria for Power, Instrumentation, and Control Portions of Safety Systems" (which endorses IEEE Std 603, "IEEE Standard Criteria for Safety Systems for Nuclear Power Generating Stations"), depending upon the applicant/licensee's commitment regarding these design criteria. This procedure is detailed in Appendix 7.1-B for ANSI/IEEE Std 279 and in Appendix 7.1-C for IEEE Std 603. The procedures in Appendices 7.1-B and 7.1-C address specific design requirements. Appendices 7.1-B and 7.1-C discuss ANSI/IEEE Std 279 and IEEE Std 603, respectively, and how they are used in the review of the interlock systems. Although the primary emphasis is on the equipment comprising the interlock systems, the reviewer should consider the interlock functions on a system level. The interlock systems design should be compatible with the SAR Chapter 15 design bases accident analyses. It is not sufficient to evaluate the adequacy of the interlock systems only on the basis of the design meeting the specific requirements of ANSI/IEEE Std 279 or IEEE Std 603. The interlock systems review should address the applicable topics identified in Table 7-1. Appendix 7.1-A describes review methods for each topic. Major design considerations that should be emphasized in the review of the interlock systems are identified below. • Single-failure criterion — See Appendix 7.1-B item 3 or Appendix 7.1-C item 6. • Quality of components and modules — See Appendix 7.1-B item 4 or Appendix 7.1-C item 8. • Independence — See Appendix 7.1-B items 7 and 8 or Appendix 7.1-C item 11 and 24. • System testing and inoperable surveillance — See Appendix 7.1-B items 10 and 11 or Appendix 7.1-C item 12, 13, and 27. • Use of digital systems — See