Sodium Fire Probabilistic Safety Assessment of Primary Cold Trap Room for China Experimental Fast Reactor

The sodium fire scenarios after the fire was ignited in primary cold trap room of China Experimental Fast Reactor were deduced using event tree method. The systems related to the accident were modeled using fault tree method. Thereby, the conditional occurrence probabilities of all sodium fire sequences were calculated. The results show that 25 typical sodium fire accident sequences are obtained in total, and 19 sequences have lower probabilities of occurrence. Among the 6 sequences with relatively higher probabilities, 4 sequences cause minor consequences, and the remaining 2 sequences require a detailed hazard evaluation in the next work because of the uncertainty.