Kidde Graviner's engine compartment fire protection system has been designed to detect engine fires caused by fuel leaks or overheating of the engine. By mid-1999 some 35,000 vehicles in 40 countries had been fitted with Kidde Graviner detection systems.

Atypical engine compartment system consists of a control unit, FIREWIRE sensors and mounting hardware, extinguishant distribution system, extinguishers and mounting brackets.

The extinguisher is normally mounted outside of the engine compartment with the FIREWIRE continuous fire detector being mounted around the engine compartment. Extinguishing is achieved utilising a high-rate discharge system.

The control unit will provide a warning signal if a fire is detected within the engine compartment. The control unit has the provision for automatic operation whereby the extinguishant would be discharged immediately following detection of a fire.

FIREWIRE control units draw minimal powerfromthe vehicle batteries and it is recommended that the system is connected to the live side of the master switch thereby providing 24 hour protection, even when the vehicle is left unattended.

The FIREWIRE element consists of a stainless steel capillary approximately 1.8 mm in diameter which houses a central electrode. This electrode is coaxially located by temperature sensitive semiconductive materials giving a construction that is both lightweight and rugged.

The installation in the engine compartment is fireproof and resettable. It is equally important to provide the crew with a 'Fire Out' signal so that they are able to continue their mission confident in the knowledge that the fire has been extinguished.

Kidde Graviner manufactures a range of extinguishers for use with FIREWIRE detection systems. The extinguishers are electrically actuated andapredetermined number can be linked through the control unit to provide a tailor-made system.

In volume production since the 1960s and used by some 40 countries worldwide. By mid-1999, more than 35,000 FIREWIRE systems were in service, of which about 1,000 use the latest version of the control unit.