Fire Safety Science Digital Archive

Crimped ribbon flame arresters, when exposed to arc discharges obtained by using copper wires, prevented ignition of flammable gas on the opposite side of the arrester, by the hot metal particles penetrating the arrester apertures. However particles produced by fusing aluminium wires remained incendive after penetrating the arrester apertures. These particles reacted with the surrounding oxygen, thus maintaining their high temperature. If the fusing of the wires was accompanied by the explosion of propane-air mixture, the expanding gases assisted the passage of small incendive particles through the apertures of the arrester. The particles produced by fusing of aluminium wires may however be safeIy contained within reinforced insulating sleeving, providing it was strong enough to withstand the pressures and the temperatures generated during fusing of such wires.