Also known as: Carbonic Oxide, Flue Gas, CO Carbon Oxide
Chemical reference number (CAS): 630-08-0
What is Carbon Monoxide?
Carbon monoxide (CO) is an odorless, colorless gas. Itís formed during
incomplete burning of fuels, such as gasoline, kerosene, natural gas, oil,
coal, or wood.
Carbon monoxide is also found in cigarette smoke and vehicle exhaust. In
homes, carbon monoxide can quickly build up from a poorly vented or malfunctioning
heater, furnace, range or any fuel-powered appliance, or even from a car
left idling in a garage.
Carbon monoxide is the most common cause of fatal poisonings.
Wisconsin State Law (exit
DHS; 23 KB) now
requires carbon monoxide (CO) detectors in all residences in Wisconsin.
How can I be exposed to Carbon Monoxide?
People can be exposed to dangerous levels of CO when charcoal, gas, oil,
or wood are burned in poorly ventilated areas. Breathing automobile exhaust
in a closed area can also result in CO poisoning.
Gas-fueled furnaces and water heaters can produce dangerous CO levels if
they are malfunctioning. Common situations for CO poisoning include: using
gasoline powered generators indoors, idling automobiles in enclosed garages,
using propane heaters indoors, and allowing children to ride inside enclosed
truck beds. Smoke from tobacco products and wood fires also contains carbon
About 50% of all CO poisonings occur in the home. Other common settings
include cars, cabins, and tents. About 40% of CO poisonings are
and 10% occur at worksites. Work exposure is more likely where fuel-powered
engines are used in enclosed areas.
What are the effects of Carbon Monoxide exposure?
Exposure to low levels of this odorless gas can produce a throbbing
headache, dizziness, fatigue, mental confusion, and shortness of breath.
Higher exposures result in severe headache, weakness, dizziness, nausea,
irregular heartbeat, and unconsciousness.
Occasionally, these symptoms can be mistaken for symptoms of the flu.
Exposure to very high levels of carbon monoxide can cause seizures, coma,
respiratory failure, and death. Exposure during pregnancy is associated with
birth defects and fetal death.
In addition to the toxic effects of CO, this gas is very flammable and
high concentrations may be explosive.
In general, chemicals affect the same organ systems in all people who are
exposed. However, the seriousness of the effects may vary from person to
person. A person's reaction depends on several things, including individual
health, heredity, previous exposure to chemicals including medicines, and
personal habits such as smoking or drinking. Itís also important to consider
the length of exposure to the chemical.
How can I avoid exposure?
- Have your furnace, gas stove, and fireplace checked annually by a qualified
professional. Have the professional check for proper ventilation and function.
- All homes must be equipped with
carbon monoxide detectors (exit
DHS; PDF 23 KB). Carbon monoxide detectors
function similarly to smoke detectors and are available at most hardware stores.
- Make sure the exhaust system on your automobile is in good working condition.
- Do not ride inside campers or trailers that are being towed by another vehicle.
- Never run an engine in an enclosed space, such as a garage. This includes cars,
snowmobiles, generators, and lawn mowers.
- Never use a gas oven to heat a home.
- Never use a charcoal grill indoors.
What do I do if I suspect a problem?
If your CO detector alarms or if you experience any of the above symptoms
and suspect carbon monoxide exposure, take immediate action. Get fresh air
immediately. Call your local
fire department and move everyone outdoors into fresh air. Do not
re-enter the building until it has been inspected and declared safe.
Carbon monoxide is eliminated from the body over a period of hours.
Although CO levels can be measured in exhaled breath, urine, blood and other
tissues, no reliable method exists to determine the level of your exposure.
For more information:
Environmental Health Home
Toxic Chemical Fact Sheets
September 25, 2013