A consideration about the various situation occurred after the accident of the Fukushima Daiichi Nuclear Power Station. About exposure dose of the evacuation especially

It seems the most important among the various situation happened that the evacuation of residents had been carried out after the accident of the Fukushima Daiichi Nuclear Power Station. There are both of results of the environmental radiation monitoring of 2011, 2012 and 2013, and calculation or assumption method of avoided annual exposure dose due to evacuation in this paper. And so, calculation or assumption results and some consideration concerning that are indicated here. The evacuation areas were decided based on this assumption. The many people hope to come back. If the radiation dose level become under the standard of restriction and the many people take understanding of the radiation influence, the many people will come back. In order to achieve this purpose, the radioactive decontamination will be need in some case. (author)