In the case of a fire in a vehicle; an airbag system is a potential bomb. The gas-generating substance in an air bag system will slowly heat up to its ignition temperature at which point all of the substance ignites simultaneously. This problem can be overcome if a thermal fuse is used. The thermal fuse should be designed to ignite before the gas-generating substance and hence will prevent an explosion if there is a fire. With new gas-generating substances used in airbag systems; however; new demands are made on thermal fuses. This is because the new substances have lower ignition temperatures than earlier ones. In order to get a satisfying effect from a thermal fuse; its ignition temperature should be a great deal lower than that for the gas-generating substance. The earlier thermal fuse developed by Bepab and currently in use by Autoflator has an ignition temperature between 200 and 225 ¬įC. This value is too high for new gas-generating substances and for this reason a new composition for the thermal fuse had to be developed.