The structure of safety of fire wall and structure of building having a structural opening requiring fire protection

摘要

There is provided a fire stop device (10) having a closure for a conduit (20) passing through an aperture extending through a wall, floor or the like. Fire resistant movable closure (22) means are operatively associated with the aperture. The closure means are movable between a first retracted position and a second functional position wherein the aperture is closed-off by the closure means. Self-sustaining restraining means of a heat disposable low-temperature melting metallic substance are used, the material being dispersible into a non-sustaining form when heated above the melting temperature thereof. The restraining means retains the closure means in the first position while permitting it to move to the second position when the substance is dispersed upon being heated. Means (26) are also provided for normally urging the closure means in the second position. Thus normally combustible thermoplastic conduits can be used up to the fire stop without affecting its operation.