抄録
It was widely known by the Fukushima nuclear power plant disaster at the nuclear power plant that it may be a fatal accident. Since there is possibility of fatal damage, even if it will be unexpected accident, the nuclear power plant disaster must avoid. It consider that in order to correspond to an unexpected accident, the stop based on the definite theory of safety, especially a time concept Moreover, it consider that the safety of a nuclear power plant and the active safety which attains a high operating ratio simultaneously.
