Probabilistic Risk Assessment and Regulatory Decisionmaking: Some Frequently Asked Questions (NUREG-2201)

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Publication Information

Manuscript Completed: April 2016
Date Published: September 2016

Prepared by:
Nathan Siu
Martin Stutzke
Suzanne Dennis
Donald Harrison

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

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Probabilistic risk assessment (PRA) is an important decision-support tool at the U.S. Nuclear Regulatory Commission. The availability of experiential data for accidents, including those at the Fukushima Dai-ichi nuclear power plant, raises natural questions regarding the need for and utility of PRA, which is, at heart, a systems modeling-based analytical approach. This report addresses these questions using the format of frequently asked questions (FAQs). The FAQs are organized into four topic categories: regulatory decisionmaking, PRA basics, core damage frequency state of knowledge, and large early release frequency state of knowledge. For each FAQ, the report provides both a brief answer and a supplementary discussion elaborating on that answer. The report also includes two appendices, which provide additional technical details on quantifying uncertainty and updating data based on experience.

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