Important items (the protection against scattering flying pieces) in Units 2, 3 and 4 in the Fukushima No.2 Nuclear Power Station and Unit 1 in the Kashiwazaki-Kariwa Nuclear Power Station of The Tokyo Electric Power Co., Inc

The Nuclear Safety Commission has acknowledged as reasonable the line of measures taken by the Agency of Natural Resources and Energy (Ministry of International Trade and Industry) for the important items, i.e. the protection against scattering flying pieces in Units 2, 3 and 4 in Fukushima No. 2 Nuclear Power Station, and Unit 1 in Kashiwazaki-Kariwa Nuclear Power Station, Tokyo Electric Power Co., Inc. The examination concerning the matter was made by the subcommittee on power generating reactors in the Committee on Examination of Reactor Safety of the NSC. The scattering flying pieces from which the nuclear power plants are to be protected in reactor installation alteration are from the destruction of the impellers and other of recirculation pumps. The examination made by the subcommittee is described as follows: the inspection in the construction of the pumps, the behavior of the pump impellers in normal operation, a loss-of-coolant accident and pump resonance rotation, etc. (Mori, K.)