CARBON MONOXIDE

What is carbon monoxide? Carbon monoxide [with the chemical formula CO] is a colorless, odorless, tasteless but highly toxic gas. Despite its serious toxicity, CO plays a highly useful role in modern technology.

Where does carbon monoxide come from? Carbon monoxide is produced by the incomplete combustion [oxidization] of fossil fuels. In leisure vehicles the most likely source of carbon monoxide is from faulty gas appliances. For gas to burn completely an appliance needs to have a good air supply, proper gas supply pressure and gas type, clean burning apparatus, adequate ventilation, and a sound unobstructed flue for the removal of the products of combustion. A clean burning gas appliance will produce flue gases that consist of water vapour and carbon dioxide. Faults in any of these due to lack of maintenance, blocked flues etc can lead to the combustion process being starved of oxygen (vitiation), and causing incomplete combustion, and therefore the production of carbon monoxide.

What makes carbon monoxide so dangerous? When we breath, the oxygen that enters our lungs is picked up and carried to the various cells of our body by a substance called hemoglobin, contained within each of our red blood cells. Carbon monoxide permanently blocks the oxygen carrying mechanism of the hemoglobin, making it permanently incapable of carrying oxygen.  A relatively low concentration of Carbon monoxide can quickly deactivate enough red blood cells to cause oxygen starvation of the brain and vital organs, leading to unconsciousness and death.

At what level does carbon monoxide become toxic? For healthy adults, CO becomes toxic when it reaches a level higher than 50 ppm (parts per million) with continuous exposure over an eight hour period.. When the level of CO becomes higher than that, a person will suffer from symptoms of exposure. Mild exposure over a few hours (a CO level between 70 ppm and 100 ppm) include flu-like symptoms such as headaches, sore eyes and a runny nose. Medium exposure (a CO level between 150 ppm to 300 ppm) will produce dizziness, drowsiness and vomiting. If you suspect the effects of CO, Get you and your family to a Doctor in the first instance. Extreme exposure (a CO level of 400 ppm and higher) will result in unconsciousness, brain damage and death.

How can Carbon monoxide be produced? Because Carbon monoxide is so fundamentally important that many methods have been developed for its production. Producer Gas is formed by combustion of carbon in oxygen at high temperatures Water Gas is produced via the endothermic reaction of steam and carbon H2O + C → H2 + CO

Because natural sources of carbon monoxide are so variable from year to year, it is extremely difficult to accurately measure natural emissions of the gas. Carbon monoxide has an indirect radiative forcing effect through chemical reactions with other atmospheric constituents Through natural processes in the atmosphere, it is eventually oxidized to carbon dioxide. Carbon monoxide concentrations are both short-lived in the atmosphere and spatially variable.

Carbon monoxide, though thought of as a pollutant today, has always been present in the atmosphere as a product of volcanic activity. It also occurs naturally in bushfires. The average global background concentrations of 0.1 ppm carbon monoxide in air reflect a balance between formation and removal rate. If there were no removal of carbon monoxide, the average atmospheric concentration would increase at the rate of 0.06 to 0.5 ppm/yr.