Probabilistic Evaluation of the Safety of Babcock and Wilcox Nuclear Reactor Power Plants with Emphasis on Historically Observed Operational Events.

摘要

The report summarizes a study performed by Brookhaven National Laboratory for the Office of Nuclear Reactor Regulation, Division of Engineering & System Technology (A/D for Systems), U.S. Nuclear Regulatory Commission. The study was requested by the NRC to assist their staff in assessing the risk significance of features of the Babcock & Wilcox (B&W) reactor plant design in the light of recent operational events. The study focuses on a critical review of submissions from the B&W Owners Group (BWOG) and as an independent assessment of the risk significance of 'Category C' events at each operating B&W reactor. Category C events are those in which system conditions reach limits which require significant safety system and timely operator response to mitigate. A precursor study for each of the major B&W historical Category C events also was carried out. In addition, selected PRAs for B&W reactor plants and plants with other pressurized water reactor (PWR) designs were reviewed to appraise their handling of Category C events, thereby establishing a comparison between the risk profiles of B&W reactor plants and those of other PWR designs.