Overview of nuclear power plant risk analysis

A methodology to identify and quantify the risks associated with nuclear power plant operation has evolved over the past few years. Extensive analyses are performed to quantify, not only the overall plant risk, but individual risk contributors as well. These analyses also provide information that may be used to reduce any potential risk contributors. This paper will present an overview of the general methodology as applied to nuclear power plants and will include identification of possible accidents (plant-centered, seismic, fire, etc.), modeling of each accident progression, modeling of the unavailability of safety-related plant systems necessary to mitigate the accident and operator response to the accident. The frequency of the major risk contributors for several plants will be included in the paper