has role has input has output chemical entity fuel oxidising agent environmental material gaseous environmental material combustion process explosion process http://orcid.org/0000-0002-3410-4655 envoPolar A process during which a material entity undergoes a rapid increase in volume, releasing gasses and various forms of energy, often including thermal, light and sound energy. Supersonic explosions are known as detonations and subsonic explosions as deflagrations. explosion