Document: NUREG-0800
Document ID: 062bafc6-0bc5-4a2f-a566-7200c0c49d7a
Document Type: srp
Title: ENGINEERED SAFETY FEATURES SYSTEMS
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1515/ML15159B099.pdf
Revision Date: 2023-06
Chapter: 7
Section ID: 7.3
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CFR Title: 

Content:
testable and are operable using either onsite or offsite power (assuming only one source is available). Additionally, the controls associated with redundant ESF systems are independent and satisfy the single-failure criterion and, therefore, meet the relevant requirements of General Design Criteria 34, 35, 38, and 41. The conclusions noted above are based upon the requirements of (IEEE Std 279-1971 or IEEE Std 603-1991) with respect to the design of the ESFAS. Therefore, the staff finds that the ESFAS satisfies the requirements of 10 CFR 50.55a(h). The applicant or licensee has also incorporated in the system design the (recommendations of the TMI task action plan items or the requirements of 10 CFR 50.34(f)), (identify item number and how implemented) which the staff has reviewed and found acceptable. In the review of the ESFAS, the staff examined the dependence of this system on the availability of essential auxiliary systems. Based on this review and coordination with those having primary review responsibility of auxiliary supporting features and other auxiliary features systems, the staff concludes that the design of the ESFAS is compatible with the functional requirements of auxiliary supporting features and other auxiliary features systems. 2. Note: The following finding applies to systems involving computer-based components. Based on the review of software development plans and the review of the computer software 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 ESFAS satisfies these requirements of General Design Criteria 1 and 21. Based on the review of the applicant/licensee’s defense-in-depth and diversity analysis, the staff concludes that the ESFAS complies with the criteria for defense against common-cause failure in digital instrumentation and control systems.