Document: NUREG-0800
Document ID: 861c72fa-b163-4443-a01e-48d1504c12a6
Document Type: srp
Title: INTERLOCK SYSTEMS IMPORTANT TO SAFETY
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1515/ML15159B156.pdf
Revision Date: 2023-06
Chapter: 7
Section ID: 7.6
CFR Part: 
CFR Title: 

Content:
E Std 603-1991. 3. SRP Appendix 7.1-D provides guidance for evaluating conformance to the acceptance criteria contained in RG 1.152, “Criteria for Use of Computers in Safety Systems of Nuclear Power Plants,” which endorses IEEE Std 7-4.3.2, “IEEE Standard Criteria for Digital Computers in Safety Systems of Nuclear Power Generating Stations.” III. REVIEW PROCEDURES The reviewer will select material from the procedures described below, as may be appropriate for a particular case. Typical reasons for such a nonuniform emphasis are the introduction of new design features or the utilization in the design of features previously reviewed and found acceptable. These review procedures are based on the identified SRP acceptance criteria. For deviations from these specific acceptance criteria, the staff should review the applicant’s evaluation of how the proposed alternatives to the SRP criteria provide an acceptable method of complying with the relevant NRC requirements identified in Subsection II. SRP Section 7.1 describes the general procedures to be followed in reviewing any instrumentation and control system. This part of SRP Section 7.6 highlights specific topics that should be emphasized in the interlock systems review. 1. The review should include an evaluation of the interlock system design against the guidance of IEEE Std 603-1991 or IEEE Std 279-1971, depending on the applicant or licensee’s commitment regarding these design criteria. For computer-based interlock systems, the guidance is provided by RG 1.152, which endorses IEEE Std 7-4.3.2. These procedures are detailed in SRP Appendix 7.1-B for IEEE Std 279-1971, SRP Appendix 7.1-C for IEEE Std 603-1991, and SRP Appendix 7.1-D for IEEE Std 7-4.3.2. SRP Appendices 7.1-B and 7.1-C discuss IEEE Std 279-1971 and IEEE Std 603-1991, respectively, and how they are used in the review of the interlock systems. SRP Appendix 7.1-D discusses the criteria of IEEE Std 7-4.3.2 and how they are used in the review of