[1M08-11] External Hazard Including Security Issue

[1M08] Research and Development of Probabilistic Risk Assessment Methodology of External Hazard Combinations

Identification of Hazard Combinations in terms of Impacts on SFR Decay Heat Removal System with Final Heat Sink of Ambient Air

*Yasushi OKANO¹, Hidemasa Yamano¹, Takashi Takata¹, Hiroyuki Nishino¹, Kenichi Kurisaka¹ (1. Japan Atomic Energy Agency)

Keywords:SFR, Air cooling, Ultimate heat sink, External hazard, Combinational hazard, PRA

External hazard related to meteorological phenomena may impact on decay heat removal system using ambient air as an ultimate heat sink such as in sodium-cooled fast reactor system. This study identify the combination of external hazards to be considered and the items to be quantified for probabilistic risk assessment from the view point of strength and affecting duration of the hazard in case that secondary external hazard which has predicted appearance frequency overlaps after an primary external hazard which is very rare but high consequence.