Approaches to Resolve Safety Issues Related to Sodium as a Coolant

Concluding Remarks: • Sodium handling technology has been established by means of operational experiences. • Major safety concerns about sodium as the coolant toward commercialization are following two points. › To ensure reliability of sodium contained components aiming at higher plant availability; › To prevent sodium chemical activity from becoming causes of core damage even under design extension conditions. • It is required to clarify DECs for sodium chemical activity and to make common understanding among the SFR developing countries. • DECs should be determined based on mechanistic consideration not on a priori manner.