Document: NUREG-0800
Document ID: fe8ec6c2-e960-404c-854f-55c77bde1672
Document Type: srp
Title: NUREG-0800
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML2400/ML24005A077.pdf
Revision Date: 2024-05
Chapter: 7
Section ID: 7
CFR Part: 
CFR Title: 

Content:
the correct area of review and level of expertise are applied to the evaluation effort. For example, a reactor safety system engineer should perform the evaluation of a best-estimate analysis for each postulated accident (PA) or other event, while the I&C technical reviewer would be responsible for the determination of adequate independence in the design of a proposed diverse actuation system. A. BACKGROUND CCF has been a concern of the U.S. Nuclear Regulatory Commission (NRC) and has been addressed as part of the licensing process throughout its history (in part by defense in depth and diversity). For example, as noted in General Electric Topical Report NEDO-10189, “An Analysis of Functional Common-Mode Failure in General Electric Boiling Water Reactor Protection and Control Instrumentation,” in early 1969, concern for possible effects of common- mode-type failures on plant operation—particularly in regard to nuclear safety functions—led the Atomic Energy Commission (AEC) to request the various reactor manufacturers to systematically examine their plant designs in that respect. Furthermore, in 1971 (36 FR 3255), the AEC promulgated the final version of Title 10 of the Code of Federal Regulations (10 CFR) Part 50, “Domestic Licensing of Production and Utilization Facilities,” Appendix A, “General Design Criteria for Nuclear Power Plants,” which now states the following: The development of these General Design Criteria is not yet complete. For example, some of the definitions need further amplification. Also, some of the specific design requirements for structures, systems, and components important to safety have not as yet been suitably defined. Their omission does not relieve any applicant from considering these matters in the design of a specific facility and satisfying the necessary safety requirements. These matters include: ...(4) Consideration of the possibility of systematic, nonrandom, concurrent failures of redundant elements in the design