Addressing the Issue of PRA Quality

摘要

In 1995, the U.S. Nuclear Regulatory Commission (NRC) issued a Policy Statement on the use of probabilistic risk analysis (PRA), encouraging its use in all regulatory matters. The Policy Statement states that "....the use of PRA technology should be increased to the extent supported by the state of the art in PRA methods and data and in a manner that complements the NRC's deterministic approach." Since that time, many uses have been implemented or undertaken, including modification of NRC's reactor safety inspection program and initiation of work to modify reactor safety regulations. Consequently, confidence in the information derived from a PRA is an important issue: the accuracy of the technical content must be sufficient to justify the specific results and insights that are used to support the decision under consideration. Regulatory Guide 1.200 has been developed to describe one acceptable approach for determining that the quality of the PRA, in toto or for those parts that are used to support an application, are sufficient to provide confidence in the results such that they can be used in regulatory decision making for light-water reactors. This guidance is also intended to reflect and endorse guidance provided by standards-setting and nuclear industry organizations. When used in support of an application, this regulatory guide is intended to obviate the need for an in-depth review of the PRA by NRC reviewers, allowing them to focus their review on key assumptions and areas identified by peer reviewers as being of concern, that are relevant to the application. Consequently, this guide will provide for a more focused and consistent review process.