Spark Arrestor are designed specifically for preventing the risk of fire, due to the ignition of flammable materials, caused by spark emission from the exhausts of internal combustion engines. The risk of fire caused by exhaust sparks is so high that access to many sites is barred unless engines are fitted with spark arrestors, and many countries have legislation to this effect. The risk is greatest with diesel engines, where carbon can build-up and be ignited. The high ratio of oxygen which is present in the exhaust pipe (when the engine goes off load) maintains the ignition of partially burnt carbon particles which are then discharged as high dangerous sparks.
