Coke oven gas /koʊk ˈoʊvən ɡæs/ – a flammable gas released during the coking of coal. It contains on average 55-60% hydrogen, 20-30% methane, 5-7% carbon monoxide. The lower calorific value is 17.2-18.8 MJ/m. It is used as fuel in industrial furnaces, to provide gas to the population, and as a raw material in the chemical industry.