Asbestos was a common material used in electrical wiring insulation, which is used to prevent deadly fires in buildings. Almost all electric wiring is insulated by electrical cloth, a fire and heat-resistant material wrapped around metal wires to prevent fire.Click to see full answer. In this way, how can you tell if wire is asbestos?Turn the flashlight on and look closely at the end of the wires where they are screwed to the socket. If the outside of the wire is black fabric and you can see white fiber where the bare wire is sticking out from the insulation then the wiring has asbestos insulation wrapped around it.Also Know, is cloth wiring dangerous? Cloth Wiring is considered a fire hazard for most insurance companies due to the the wiring overheating the cloth and starting a fire. Cloth wiring considered extremely dangerous and replaced immediately. Most cloth wiring found in houses may not be dangerous. Also question is, does cloth covered wire contain asbestos? The Use of Asbestos in Wiring Insulation for wiring may include paper or cloth materials, tapes, and other materials. Any of these materials may be impregnated with asbestos fibers.Does knob and tube wiring contain asbestos?Knob and tube wiring used cloth insulation. The insulation is also somewhat flammable. Some knob and tube insulation intended for industrial use contained asbestos, which reduced the risk of fire, but can cause cancer. Unlike modern wiring, splices were not contained in a protective box.