MODEL RELEASED. Asbestos monitoring. Passive asbestos sampler (round) on the jacket of a workman. The sampler uses electrostatic charge to attract airborne dust particles, which may include asbestos fibres. The sampler is used for five days and then sent to a laboratory where the particles are identified and counted using an electron microscope. Asbestos is heat resistant and so used in fire-proof fabrics and electrical and heating insulation. It is highly toxic when inhaled as dust particles. Prolonged exposure causes the fatal lung disease asbestosis.