Fire survival cables are cables that are designed to continue to operate for a defined minimum period of time during a fire or high temperatures. Many manufacturers refer to these products as “fire-resistant” cables. Originally the need for cables to operate for longer in the circumstances of fire was purely driven by the need for Fire Alarms to be able to continue to work and serve their purpose.
Mineral insulated Cable (MI, also known as MIMS, MIC or MICC) was the earliest type of fire survival cable. The MI cable consists of copper conductors surrounded by mineral powder insulation (usually magnesium oxide) contained within an outer metal sheath, usually a copper tube. Though MI cable continues to be the traditional design of fire survival cable, alternative fire survival cable designs use polymeric insulation and tapes (often mica) and are now in wider use than MI cables. In the event of a fire, the polymeric insulation forms protective ash so that the cable can continue to operate.
Traditionally fire survival cables were low voltage energy cables, essentially building wire but with enhanced fire resistance. In more recent years other types of cables have become available with fire survival properties, including coaxial cable, twisted pair communication cable and fibre optic cable. Fire survival communication cables were aimed at applications such as, emergency telephone lines, CCTV systems public address systems and of course fire alarms that have to continue to operate in the event of a fire.
The need for Fire Survival LAN Cables has been debated over recent years, not because of their performance with regards their ability to cope in the event of a fire but because of concerns as to whether the cables could provide means for the fire to spread throughout a building and also the potential for harmful omissions to be given off by the cables when exposed to a fire.
Fire survival cables in the event of a fire
The answer to the need for buildings to be able to operate quickly and efficiently in the event of a fire today has the ideal solution in Fire Survival Fibre Optic Cable. Fibre Optic Cable running on an IP network will increase speed, and reliability as well as giving diverse flexibility. Should a fire occur in one phase of a building the network can remain fully functional and the situation can be monitored from another phase in the building.
