Abstract: A fire damper for sealing a conduit which extends through a concrete slab to prevent fire and toxic gases from passing from one side of the slab to the other, includes a housing which has a partially spherical rotatable valve. The rotatable valve has an internal passageway of substantially the same diameter as an internal diameter of the conduit. The rotatable valve is rotatable within the housing between an open orientation whereby fluid flow through the damper is substantially unimpeded and a closed orientation. The rotatable valve is actuated by a heat detector in the form of two rings of lead alloy located between the housing and the rotatable valve. The damper may also include a deformable seal disposed between the housing and the rotatable valve.

Abstract: A fire collar, for location in a concrete slab around a deformable conduit, has a housing with a passageway through which the conduit passes. The collar has the housing in which are located two compression springs with arms which are held against the force of the springs by fusible links. When the heat of a fire on one side of the slab causes the fusible links to soften or melt, the force of the springs causes the spring arms to rotate towards the conduit, engaging the conduit and collapsing it. An intumescent layer may be provided around the conduit to assist in collapsing it.

Abstract: A fire collar or fire damper for location within a concrete slab of a building. The device incorporates a damper arrangement (12) and a heat detector (18, 19) comprising a metal alloy or lead which melts when a preset temperature is reached, causing the damper arrangement to seal off associated pipework or ducting.