[en] A vessel has a multiple structure, and functions are distributed to each of the constitutional vessels. The distribution includes distribution of shielding functions, and the shielding functions may not always be provided to one vessel, but can distributed to two or more vessels. Namely, when standards of dose rate during storage are moderated than those during transportation, it is suffice that the vessels have shielding property by so much required during storage, so that the properties of the difference between the shielding property during storage and those required during transportation can be saved by so much. Accordingly, the weight of the vessels during storage can be reduced compared with the vessels having shielding properties satisfying the transportation standards, namely, the capacity of the containers can be increased thereby enabling to reduce the number of vessels. Procedures for removing activated or contaminated wastes are made apparent to make operations smooth. (N.H.)

[en] A radiation shielding member comprises a metal vessel and a liquid therein, and is disposed to the upper surface of a lower flange of a reactor core shroud. Waterproof hot wires are contained in the liquid and are connected to a power source disposed at the outside. Electric current is supplied to the hot wires to elevate the temperature of the liquid, and the temperature of the vessel is kept higher than an atmospheric temperature thereby suppressing generation of dew condensation or water droplets. In addition, a water repellent coating is applied to the shielding member itself to prevent deposition of water droplets. Further, the bottom of the shielding member is inclined, and a water droplet-recovering vessel is disposed at the lower portion of the shielding member, so that the water droplets collected by the inclination of the bottom are recovered to the water droplet recovering vessel. With such a constitution, access of an operator to the inside of a reactor pressure vessel is facilitated, and at the same time, the working circumstance at the reactor bottom can be improved. (I.N.)