The quality fire proof cable is also called mineral insulated cable such as metal tube magnesium oxide, which is mainly composed of copper core, copper sheath and magnesium oxide insulating material. The fire proof cable has the characteristics of high fire resistance, high temperature resistance, and resistance to mechanical damage. The long-term use temperature is 250 ° C, and it can be maintained at 950 to 1000 ° C for 3 hours (international standard 90 minutes). The quality fire proof cable even can be close to the melting point of copper in a short time or in an extraordinary period.

There are also many types of the fire proof cables, which are the general term for cables with fireproof performance. It includes general flame-retardant cables and fire-resistant cables. However, the cost of the quality fire proof cable is relatively expensive, and they do not have the flexibility of ordinary cables. At present, they are mainly used in civil buildings for special loads that are important to ensure personal and property safety.
The quality fire proof cable uses polyolefin as the outer sheath, which has the function of retarding the spread of the flame along its surface, so that the fire does not expand. In tunnels, shafts or cable interlayers with dense cables, in order to prevent the cables from catching fire and causing serious accidents, it is recommended to use the quality fire proof cable for cables of 35kV and below.