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Indoor Air Quality (IAQ)

What is carbon monoxide?

Definition

Carbon monoxide (CO) is a colorless, practically odorless, and tasteless gas or liquid. It results from incomplete oxidation of carbon in combustion.  Burns with a violet flame.  Slightly soluble in water; soluble in alcohol and benzene.  Specific gravity 0.96716;  boiling point -190oC; solidification point -207oC; specific volume 13.8 cu. ft./lb. (70oF).  Auto ignition temperature (liquid) 1128oF.  Classed as an inorganic compound.
Source:  "The Condensed Chemical Dictionary," 9th ed., revised by Gessner G. Hawley, Van Nostrand Reinhold Co., NY, 1977.

Sources of Carbon Monoxide

Unvented kerosene and gas space heaters; leaking chimneys and furnaces; back-drafting from furnaces, gas water heaters, wood stoves, and fireplaces; gas stoves; generators and other gasoline powered equipment; automobile exhaust from attached garages; and tobacco smoke.  Incomplete oxidation during combustion in gas ranges and unvented gas or kerosene heaters may cause high concentrations of CO in indoor air.  Worn or poorly adjusted and maintained combustion devices (e.g., boilers, furnaces) can be significant sources, or if the flue is improperly sized, blocked, disconnected, or is leaking.  Auto, truck, or bus exhaust from attached garages, nearby roads, or parking areas can also be a source.

Health Effects Associated with Carbon Monoxide

At low concentrations, fatigue in healthy people and chest pain in people with heart disease. At higher concentrations, impaired vision and coordination; headaches; dizziness; confusion; nausea. Can cause flu-like symptoms that clear up after leaving home. Fatal at very high concentrations.  Acute effects are due to the formation of carboxyhemoglobin in the blood, which inhibits oxygen intake.  At moderate concentrations, angina, impaired vision, and reduced brain function may result.  At higher concentrations, CO exposure can be fatal.

For more information, see - Carbon Monoxide's Impact on Indoor Air Quality