Document: NUREG-0800
Document ID: b2d15b43-96b5-4876-877d-f6ba1944c6d7
Document Type: srp
Title: INTERLOCK SYSTEMS IMPORTANT TO SAFETY
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1602/ML16020A092.pdf
Revision Date: 2023-06
Chapter: 7
Section ID: 7.6
CFR Part: 
CFR Title: 

Content:
ns 3.10 and 3.11 of the SER address the qualification programs to demonstrate the capability of these systems and components to survive these events. Therefore, the staff finds that the identification of these systems and components satisfies the requirements of General Design Criteria 2 and 4. The staff reviewed the bypassed or inoperable status indication of safety interlocks. The staff finds that appropriate bypass indications are provided to give the operators timely information and status reports so the operators can mitigate the effects of unexpected system unavailability. The bypass indications satisfy the guidelines of RG 1.47, “Bypassed and Inoperable Status Indication for Nuclear Power Plant Safety Systems.” Therefore, the staff concludes that the safety interlock systems satisfy the applicable requirements of 10 CFR 50.55a(h) and 10 CFR 50.34(f)(2)(v). The nonsafety interlock 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 7.6-9 Revision 6 – August 2016 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