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:
ck systems are appropriately isolated from safety systems. Therefore, the staff concludes that the isolation of these systems from safety systems satisfies the requirements of 10 CFR 50.55a(h) and the requirements of GDC 24. Based on the review of interlock safety system design, the staff concludes that the safety portions of the interlock systems comply with the requirements of (IEEE Std 279-1971 or IEEE Std 603-1991). Therefore, the staff finds that the interlock safety systems satisfy the requirements of 10 CFR 50.55a(h). In the review of the interlock systems, the staff examined the dependence of this system on the availability of auxiliary supporting features and other auxiliary features. Based on this review and coordination with those having primary review responsibility of auxiliary supporting features and other auxiliary features, the staff concludes that the design of the interlock systems is compatible with the functional requirements of auxiliary supporting features and other auxiliary features. 2. Note: The following finding applies to systems involving digital computer-based components. Based on the review of software development plans and the inspections of the computer development process and design outputs, the staff concludes that the computer systems meet the guidance of RG 1.152. Therefore, the special characteristics of computer systems have been adequately addressed, and the staff finds that the interlock systems satisfy the requirements of 10 CFR 50.54(jj) and 50.55(i), and General Design Criteria 1, 13, and 19. 3. For DC and COL reviews, the findings will also summarize the staff’s evaluation of the requirements and restrictions (e.g., interface requirements and site parameters) and COL action items relevant to this SRP section. 4. Note: The following conclusion is applicable to all applications. The conclusions noted above for the interlock systems are applicable to all portions of the systems except for the following, for which acceptance