Abstract: A fire collar (10) including a housing defining an opening (18) and a passage (20) adapted to receive a conduit therethrough. A layer of intumescent material (43) surrounds the conduit and is supported by the housing adjacent the opening. Torsion springs (34) are mounted between the housing and the intumescent material to surround the conduit and are held in a non-operational position by fusible links (41). When the heat of a fire melts the links, each torsion spring acts in a longitudinal plane of the passage to assist the intumescent material to collapse the conduit and seal the passage against advancement of the fire.

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 present temperature is reached, causing the damper arrangement to seal off associated pipework or ducting.