Document: NUREG-0800
Document ID: f4b8f0c1-9a14-46be-88c9-a6cb74d64dff
Document Type: srp
Title: Rev. 4 — June 1997
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0525/ML052500499.pdf
Revision Date: 2023-06
Chapter: 7
Section ID: 7
CFR Part: 
CFR Title: 

Content:
nd 10 CFR 50.49 satisfy the requirements for equipment qualification to harsh environments and seismic events. Guidance for the review of this equipment qualification is given in SRP Sections 3.10 and 3.11. 10. Section 5.5 — System Integrity Information provided in Sections 4.7 and 4.8 is reviewed to confirm that the design includes the qualification of equipment for the conditions identified in the design bases. Failures may not be credited to protect the integrity of other equipment. The review should confirm that tests have been conducted on safety system equipment components and the system racks and panels as a whole to demonstrate that the safety system performance is adequate to ensure completion of protective actions over the range of transient and steady-state conditions of both the energy supply and the environment. Where tests have not been conducted, the applicant/licensee should confirm that the safety system components are conservatively designed to operate over the range of service conditions. A special concern for digital computer-based systems is confirmation that system real-time performance is adequate to ensure completion of protective action within the critical points of time identified as required by Rev. 4 — June 1997 SRP 7.1-C-8 Section 4.10. BTP HICB-21 provides supplemental guidance on evaluating response time for digital computer-based systems, and discusses design constraints that allow greater confidence in the results analyses or prototype testing to determine real-time performance. IEEE Std 7-4.3.2 indicates that design for computer system integrity and design for test and calibration should be addressed as part of safety system integrity. Evaluation of computer system hardware integrity should be included in the evaluation against the requirements of IEEE Std 603. Computer system software integrity (including the effects of hardware-software interaction) should be demonstrated by the applicant/licensee's software safety analysis