Radiation protection issues on preparedness and response for a severe nuclear accident; Experiences of the Fukushima accident

Homma, Toshimitsu; Takahara, Shogo  ; Kimura, Masanori ; Kinase, Sakae   

The radiation protection issues on preparedness and response for severe nuclear accidents are discussed in this paper from experiences of the Fukushima Dai-ichi Nuclear Power Plant accident. The urgent protective actions such as evacuation and sheltering have been effectively implemented on the basis of the plant conditions though the national emergency plan for nuclear power plants heavily relied upon computer-based predictive models. Since there were no recommendations and criteria for long-term protective actions in the emergency preparedness guide, the revised recommendations of ICRP Publications 103, 109 and 111 have been taken into consideration for determining the temporary relocation of the inhabitants in the heavily contaminated area. Although those revised recommendations have been very helpful and useful for taking emergency protective actions, some suggestions were identified for improving emergency preparedness and response at the early stage of the accidents.