Safety Design Requirements and design concepts for SFR. Reflection of lessons learned from the Fukushima Dai-ichi accident

• To achieve safety goals for Generation IV reactor, design measures should be taken under DECs including those for external events considering the lessons learned from the Fukushima Dai-ichi NPPs accident. • In particular, core cooling under long term loss of electric power or failure of auxiliary systems such as sea water cooling systems shall be ensured by utilizing diverse decay heat removal facilities. Alternative heat removal measures under core damage situations are needed to be considered. Also countermeasures against natural disasters beyond design basis shall be considered in design. • Concepts of design measure to meet these requirements were presented. International consensus for these kind of requirements and design concepts is necessary to ensure the global safety of the nuclear power.