United States Nuclear Regulatory Commission - Protecting People and the Environment

Backfitting Guidelines (NUREG-1409)

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Publication Information

Manuscript Completed: June 1990
Date Published:
July 1990

D. P. Allison, J. M. Conran, and C. A. Trottier

Office for Analysis and Evaluation of Operational Data
U.S. Nuclear Regulatory Commission
Washington, DC 20555-0001

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The backfitting process is the process by which the U.S. Nuclear Regulatory Commission (NRC) decides whether to issue new or revised requirements or staff positions to licensees of nuclear power reactor facilities. Backfitting is expected to occur and is an inherent part of the regulatory process. However, it is to be done only after formal, systematic review to ensure that changes are properly justified and suitably defined. Requirements for proper justification of backfits and information requests are provided by two NRC rules, Title 10 of the Code of Federal Regulations, Sections 50.109 and 50.54(f). Three types of backfits are recognized. Cost-justified substantial safety improvements require backfit analyses and findings of substantial safety improvement and justified costs. Two types of exceptions, compliance exceptions and adequate protection exceptions, do not require findings of substantial safety improvements and costs are not considered. However, they are still backfits and they require documented evaluations to support use of the exceptions. Information requests (as opposed to backfits) require an analysis of the burden to be imposed to ensure that they are justified in view of the potential safety significance of the information requested. NRC procedures on backfitting include the Charter of the Committee to Review Generic Requirements for generic communications and NRC Manual Chapter 0514 and individual office procedures for plant-specific communications. Considerable guidance has been developed, control mechanisms are in place, and training has been provided to NRC and industry personnel. The Director of the Office for Analysis and Evaluation of Operational Data is responsible for oversight of backfitting programs, including obtaining industry comments. Initiatives are under way to better explain the process and conduct further training for industry and NRC personnel. Further initiatives are being considered in response to industry comments obtained in a recent survey concerning the effects of the regulatory process on licensees.

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