Characteristics of heat and flame resistant optical fiber cables

Flame resistant and flame retardant properties of various types of optical cables are investigated. As a result of the tests, the authors conclude that it is not suitable to employ the conventional 3-layer coating construction because of the weakness of thermoplastic resin coated fiber at a high temperature. By adopting the heat resistant fiber-reinforced-plastic jacketing on optical fibers, the authors have succeeded in the development of a flame resistant optical fiber cable. Furthermore this optical cable has the noninductive characteristics due to the nonmetallic construction. The cable is light in weight and small in diameter and still has the sufficient mechanical properties. Therefore, this type of cable is promising as a flame resistant optical cable for uses in severe environments such as high temperature up to 800 C half an hour.