A Preliminary Microscopical Examination of Common Fire Debris and Combustion Products

Fire-related deaths and explosive events are both large concerns in the United States (Almirall & Furton, 2004). Common low explosives and flammable materials that are often found around the home, such as smokeless powders and match heads, are often used in improvised explosive devises (IED), a common choice for explosions (Chang, Yew, & Abdullah, 2014). There are a number of methods for analyzing fire and explosion debris, but many of them are time consuming and/or require expensive instruments. Polarized light microscopy (PLM) is a relatively easy, quick, and inexpensive method for identifying a wide range of particles and fibers. Despite this, with the exception of one small entry in The Particle Atlas, PLM has not been applied to fire debris and the identification of combustion products until now (McCrone, Brown, & Stewart, 1980). PLM can be used to identify the general fuel from the combustion products, such as wood vs. drywall vs. paper products, though it cannot determine the exact fuel, such as pine vs. oak. Char seems to be the most useful combustion product for this determination.