The General Methodology of An Integrated Human Event Analysis System (IDHEAS-G) (NUREG-2198)

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Publication Information

Manuscript Completed: November 2020
Date Published: May 2021

Prepared by:
J. Xing
Y. J. Chang
J. DeJesus Segarra

Office of Nuclear Regulatory Research
U.S. Nuclear Regulatory Commission
Washington, DC 20555-0001

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This report describes a human reliability analysis (HRA) methodology developed by the U.S. Nuclear Regulatory Commission (NRC) staff, the General Methodology of an Integrated Human Event Analysis System (IDHEAS-G). IDHEAS-G was developed in response to the staff requirements memorandum (SRM) M061020, dated November 8, 2006, to the Advisory Committee on Reactor Safeguards (ACRS). The SRM directed the ACRS to, “work with the [NRC] staff and external stakeholders to evaluate different human reliability models in an effort to propose a single model for agency use or guidance on which model(s) should be used in specific circumstances.” IDHEAS-G is intended to be a human-centered, general methodology used to develop application-specific HRA methods by the NRC. It integrates the strengths of existing HRA methods and enhances HRA in: (1) application scope, (2) scientific basis, (3) HRA variability, and (4) data for HRA. An example of the use of the IDHEAS-G framework is the development of Research Information Letter 2020-02 – IDHEAS for Event and Condition Assessment (IDHEAS-ECA) and its associated software tool. IDHEAS-ECA has proven to be a useful HRA method for supporting the NRC’s risk-informed decisionmaking processes.

Page Last Reviewed/Updated Wednesday, May 12, 2021