Fire-resistant collars can prevent the propagation of a fire and the transit of toxic smoke and gas through openings in the wall or floor left by a PVC conduit that has been destroyed by fire. CSTB tested: Ref. nos. 98-e-275 in the wall 98-h-276 in the floor.
Fire-resistant collars can be used for any PVC conduit penetrating the fire-resistant wall or floor of a building that must be perfectly sealed in the event of fire. The goal of these sleeves is to restore the fire-resistant properties of a partition or slab where they are penetrated by tubes or cables.
Fire-resistant collars consist of a metal casing containing several bands of intumescent graphite.
Under the effect of heat at a temperature of around 150 °C, the graphite bands contained inside the collar expand and put pressure on the PVC conduit that has been softened by the fire. They effectively obstruct the hole left by the PVC conduit and preserve the two-hour fire resistance of the wall or floor.