Characterising the smoke produced from modern materials and evaluating smoke detectors

The increasing use of new materials in buildings prompted this investigation into the ability of smoke detectors to respond to the smoke produced by modern materials during a fire. The four test fires now used in standards to assess smoke detectors and alarms were developed in the 1980s, and represent a broad range of smoke types expected in commercial and domestic environments at that time. 

The purpose of this research project was to measure the smoke characteristics of a range of new materials in smouldering and flaming modes, and compare them with the existing four test fires specified in current standards. The performance of twelve approved ionisation and optical smoke detectors to the smoke produced from these alternative materials was also assessed.

Twenty-nine test fires were conducted and sixteen were found to be within the range bounded by the existing TF2 (smouldering wood fire) and TF5 (flaming liquid fire) test fires for smoke detector standards. The smoke alarms and detectors, installed on the ceiling and the wall, were exposed to the smoke from the test fires. They produced 6 no-responses and 270 responses, representing a 97.8% pass rate. 

It is evident that ionisation or optical detectors used in commercial and domestic environments are capable of responding to a broad range of fires inside and outside the limits of existing standards. It was confirmed that both ionisation and optical smoke detectors are attuned to detecting certain types of fires, and that existing standards remain suitable for assessing these technologies.