[en] A bag having air or like other gas, sealed therein is made of a flexible sheet such as a vinyl sheet. Several kinds of bags of large, medium and small sizes are prepared. Required number of bags of an appropriate size are connected depending on the kinds of the operation and place for installation, to form a house having an optional shape and size. Fasteners attached to the bags are used for the connection of the bags with each other. The fasteners used have excellent air tightness, tensile strength, joining and separation performances. When the house is fixed to the floor surface or the wall surface, it is constituted such that the house and the contact portion are easily joined and detached by one-touch operation by using a magic tape or the like. Further, the opening and closing mechanism by using the fastener is also used for the portion where opening and closing operation are conducted, such as a gateway for equipments and a doorway for operators. With such a constitution, radiation diffusion preventive effect is improved. Further, transportation and handling therefor can be made simple and convenient. (I.N.)