Fire caused by freeze-prevention heating wires are often used as freeze-prevention heating wires to prevent damage caused by freezing and rupture in industrial sites, buildings, apartments, water meters, fire pipes, water storage tanks, agricultural and fishery pipes and tanks. There are many ways to prevent freezing, but one of the measures commonly used in the field is to lay a heating wire on a pipe, wrap it with a tape, wrap it with a pipe insulation material, and protect it with a cover. As the construction of the freeze-prevention heating wire (Self-regulating heating cable) is inadequate, but fires are frequently caused by the freeze-prevention heating wire due to negligence in maintenance, management, and inspection, human and property damage are increasing, we hope this paper will be helpful in safety construction, maintenance, and fire investigation.