Detecting Arson Accelerants

Arsonists hardly ever simply strike a match to light a fire, using any combustible material at hand such as a piece of paper or a curtain. Such a course of action is too uncertain, since a fire lit in this way may burn itself out very quickly. Usually, an accelerant is used. A flammable liquid such as kerosene [or gasoline] is poured over a wide area of carpets and furnishings, before the match is applied. This ensures that a hot fire will follow and that the building be ablaze long before any firefighters arrive. However, what most arsonists do not know is that traces of such accelerants can be detected, even after the fire has destroyed the building. Small amounts of accelerant will seep into carpets, floorboards, plaster, brickwork and other materials and will not be consumed by the fire. The cooling effect of the water used to quench [extinguish] the fire will slow down the rate of evaporation of the accelerant and enough will usually remain to be detected.

Dr. Zakaria Erzinclioglu, Forensics, 2012