The combustion or processing of certain materials often results in the production of certain gases. When the concentration of these gases exceeds a predetermined threshold, it may be desirable to cease the combustion or processing which is directly or indirectly producing the gas. One such gas is carbon monoxide. Carbon monoxide is a colorless, odorless, tasteless gas, which is produced through an incomplete combustion of a hydrocarbon. Carbon monoxide can be produced by various fuel burning appliances, such as, fuel fired furnaces, gas hot water heaters, gas stoves, gas dryers, space heaters, vehicles, snow blowers, portable power generators, etc.
Once present, this gas circulates freely throughout a building, such as a home. If this gas is not ventilated properly, carbon monoxide poisoning may result. Carbon monoxide inhibits the blood's ability to carry oxygen to body tissue, including vital organs such as the heart and brain. When carbon monoxide is inhaled, it combines with oxygen-carrying hemoglobin of the blood to form carboxyhemoglobin. Once combined with the hemoglobin, the hemoglobin is no longer available for transporting oxygen. The amount of carboxyhemoglobin that builds up is a factor of the concentration of the gas being inhaled and the duration of the exposure. Carbon monoxide can act in the body in high concentrations, or slowly over a long period of time. Because it takes several hours to remove carbon monoxide from the body of a person, concentrations of carbon monoxide can gradually build up in the blood causing headaches, fatigue, dizziness, nausea, burning eyes, or unconsciousness.