Feasibility Study of Developing Alternative Common-Cause Failure Model for Event Assessment

Ma, Zhegang; Knudsen, James K.; Schroeder, John A.; Smith, Curtis L.

doi:10.2172/1836026

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DOE OSTI · 1836026

Feasibility Study of Developing Alternative Common-Cause Failure Model for Event Assessment

Ma, Zhegang·Knudsen, James K.·Schroeder, John A.·Smith, Curtis L.

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Abstract

This report is a revision of the original report, INL/LTD-14-33376. The original report, which was a limited distribution to the Nuclear Regulatory Commission (NRC) only and not available to the public, was revised as this report for public distribution. The report presents the feasibility study of alternative common-cause failure (CCF) models that could be used for event assessment in the Standardized Plant Analysis Risk (SPAR) models. The current CCF model used by the SPAR models is the alpha factor model. The proposed alternative CCF models are the partial alpha factor model and general dependency model. These alternative CCF models are reviewed and compared to the current alpha factor model, with the partial alpha factor model being identified as the preferred CCF model that could be used for event assessment in the SPAR models.

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21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS 42 ENGINEERING Causal Alpha Factor Model Common Cause Failure Event Assessment Partial Alpha Factor Model PRA SAPHIRE SPAR

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Ma, Zhegang, Knudsen, James K., Schroeder, John A., Smith, Curtis L.. 2021-09-01. Feasibility Study of Developing Alternative Common-Cause Failure Model for Event Assessment. https://doi.org/10.2172/1836026

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