Approach to assess fire risk for nuclear power plants

The results of the first fire risk assessments on an international level have shown that fires are one major contributor to the risk of a nuclear power plant depending on the plant specific fire protection concept. Therefore, fire risk assessment has today become an integral part of the probabilistic safety assessment of nuclear power plants in addition to deterministic analyses. Based on existing guidance documents a state-ofthe-art approach for performing probabilistic fire risk assessment has also been developed in Germany. This approach has been exemplarily and completely applied to a German nuclear power plant with boiling water reactor for the full power states PSA. The general approach outlines the steps necessary for performing fire risk assessment and the prerequisites for a sound and traceable database.