Fire Risk Assessment of Domestic Nuclear Power Plant Considering Fire Protection Equipment and the Damage State

Abstract

This study assessed fire risk by considering the fire protection equipment and fire damage state over time. The fire scenario of the domestic reference nuclear power plant (NPP) analyzed was the fire of the transient ignition sources in the cable spreading room. The height and time of the cable tray damaged according to the change in the heat release rates were evaluated using the closed-form algebraic equation for the plume height. The non-suppression probability was estimated using the event trees, considering the reliability of the fire protection equipment and the probability of manual non- suppression over time. The results of this study confirmed that if the non-suppression probability is evaluated as a simple product of the failure probability of automatic suppression equipment and the probability of manual non-suppression, the fire risk evaluation result may be optimistic unless the detector and the suppression equipment are independent of each other. The results of this study are expected to contribute to the systematic assessment of the fire risk of domestic NPPs.