Patent ID: 7692092

Claim:
A fire-retarding cable conduit for electrical lines in regions potentially exposed to fire comprising: a tubular base body having a first slit, an interior volume and an exterior surface, and being comprised of an intumescent material, such that the intumescent material is expandable when exposed to the effects of a fire, and the intumescent material is substantially converted to an expanded, inorganic foam after exposure to the effects of a fire causes the intumescent material to fully expand; and a sheath comprised of a glass fabric or a fused silica fabric and having a second slit, the sheath being disposed about the exterior surface of the body; wherein the first slit and the second slit are arranged such that the electrical lines are insertable into the interior volume through the first slit and the second slit, such that the intumescent material foams through an open mesh of the glass fabric or the fused silica fabric, when the conduit is exposed to fire.