Research & development of safety approach and safety assessment for the next generation SFR

Okano, Yasushi; Kurisaka, Kenichi ; Yamano, Hidemasa   ; Fujita, Satoshi; Nishino, Hiroyuki  ; Sakai, Takaaki

Preliminary safety assessments have been conducted on JSFR under the FaCT project. The main conclusions were: (1) the key safety parameters satisfy design limits, (2) passive reactor shutdown mechanism for the prevention and an in-vessel retention concept for the mitigation of severe accidents were built-in, (3) the core damage frequency was assessed to be less than 10/site-year, and risk target for earthquakes was assessed to meet the design conditions as of 2007. In the light of TEPCO's Fukushima Dai-ichi NPP accidents, the next safety-related research and development items will be: (1) In-detail Level-1 PRA on loss of heat sink type severe accidents, (2) Unreliability factor evaluations on passive safety system, (3) Accident scenario initiated by external events, (4) Risk-informed approach to extreme external hazards for clarifying reasonable design margins and (5) Establishment of harmonized safety design criteria.