Building air exhaustion device

An opening is formed on the side wall of a building such as of a nuclear power plant, and a blow out panel is held (supported) by a clip for closing the opening. A large-diameter pipeline is connected at one end to the opening so as to cover the blow out panel, and immersed at the other end in a pool water. When a pipeline such as of main steam pipelines is ruptured in the building, high temperature and high pressure coolants are flown out from the ruptured port, and the pressure in the building is elevated. The blow out panel falls off from the side of the building by the elevation of the pressure in the building. Steams or compressed air discharged from the opening is introduced to the pool through the large diameter pipeline, then the steams are condensed by the pool water and radioactive materials contained in the condensed steams are kept in the pool water. Radioactive materials contained in the released compression air are also removed into the pool water. (I.N.)