A Proposed Acceptance Process for Commercial Off-the-Shelf (COTS) Software in Reactor Applications (NUREG/CR-6421, UCRL-ID-112526)

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Publication Information

Manuscript Completed: September 1995
Date Published: March 1996

Prepared by:
G.G. Preckshot, J.A. Scott
Lawrence Livermore National Laboratory
P.O. Box 808, L-632
Livermore, California 94551

J. Gallagher, NRC Technical Monitor

Prepared for:
Division of Reactor Controls and Human Factors
Office of Nuclear Reactor Regulation
U.S. Nuclear Regulatory Commission
Washington, DC 20555-0001

NRC Job Code L1857

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This paper proposes a process for acceptance of commercial off-the-shelf (COTS) software products for use in reactor systems important to safety. An initial set of four criteria establishes COTS software product identification and its safety category. Based on safety category, three sets of additional criteria, graded in rigor, are applied to approve (or disapprove) the product. These criteria fall roughly into three areas: product assurance, verification of safety function and safety impact, and examination of usage experience of the COTS product in circumstances similar to the proposed application. A report addressing the testing of existing software is included as an appendix.

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