A flame arrester is a passive explosion protection device with no moving parts. At the core of each Amal flame arrester is a crimped metal element, which in section comprises a matrix of triangular passages or cells. All gases have a defined gap through which a flame will not pass; this is called the Maximum Experimental Safe Gap (MESG). When a gas or vapour mixture ignites, the element matrix prevents further propagation by absorbing and dissipating heat from the burning gas or vapour on the incoming side of the arrester. As the flame enters the flame arrester element, the temperature is progressively reduced. This results in the gas being cooled to below the point where auto-ignition would otherwise occur when exiting the element.

Amal are one of the few manufacturers who have their own test facilities, where a customer's actual pipe configurations or equipment can be tested. Computer-controlled test instrumentation is used to measure flame speeds and explosion pressures in test pipe-work. Amal's engineers then utilise closed circuit video equipment to accurately assess the performance of differing types of Flame Arresters, in varying situations. This impressive development and testing facility has the capability and resources to test Flame Arresters in accordance with all recognised standards.