Discussion on the Application of Fire Probability Safety Assessment to Sodium Cooled Fast Reactor

As sodium cooled fast reactor (SFR) uses liquid sodium as coolant, the risk of sodium fire is brought to reactor safety, which is different from conventional fire. Sodium is very chemically active, and violent chemical reactions can happen when sodium is exposed to air or water. Sodium fire is a typical and distinctive hazard in sodium cooled fast reactors, which is probably one of the main contributors to the total reactor risk. In this paper, the methodology of fast reactor sodium fire risk assessment is studied, and the principles and procedure of sodium fire probabilistic safety assessment (PSA) are given. The application of this technology in China Experimental Fast Reactor (CEFR) is explored, and several key problems which need more research in the future during the process of sodium fire probabilistic safety assessment are discussed.