CO is Produced when:
Carbonaceous materials are burned with insufficient oxygen. Its lethal effects have been known for centuries; in ancient Rome, "coal gas" was used for executions and suicides.
Man-made sources of CO include:
- Incomplete fuel combustion used in transport -
- Automobile/Truck exhaust
- Airplane exhaust
- Smoking of cigarettes, cigars, pipes, etc.
- Defective heating (furnace, water heater) systems
- Defective cooking appliances
- Industrial plant exhausts
- Burning of solid waste
- Detonation of explosives
Natural sources of CO also exist but they contribute very little to the overall atmospheric CO level.
- Marsh gases
- Forest fires
- Volcanic gases
- Natural gases in coal mines
- Photo-dissociation of CO in upper atmosphere
- Formation of CO during electrical storms
- Endogenous CO production by land animals
- From vegetation during seed germination
- From marine brown algae or kelp
- Marine hydrozoans: e.g. jellyfish