Carbon Monoxide

If your carbon monoxide detector goes off - Go outside and call 9-1-1.

What is carbon monoxide (CO)?
What are possible sources of carbon monoxide in the home?
What are the signs and symptoms of carbon monoxide poisoning?
What are the health effects?
Are there ways to lessen the risk of carbon monoxide poisoning?
Can carbon monoxide be detected?
Where should a carbon monoxide detector be installed?
What should I do if the carbon monoxide detector alarm goes off?
Additional Resources

What is carbon monoxide?

Carbon monoxide (CO) is a colorless, odorless, poison gas. It is produced when liquid, solid, or gas fuel is burned.

Carbon monoxide (CO) is sometimes confused with carbon dioxide (CO2). Carbon monoxide can be a poison, even at low levels, while carbon dioxide is a normal part of the breathing process.

Return to Top

What are possible sources of carbon monoxide in the home?

Under certain conditions, any fuel burning vehicle, tool, appliance or other device or equipment can produce harmful levels of carbon monoxide. Common examples include:

fuel-fired furnaces or boilers (nonelectric)
space heaters with pilot lights or open flames (for example kerosene heaters, wood stoves or fireplaces)
gas stoves or ovens, especially those with pilot lights
dryers, water heaters and refrigerators that use gas or liquid fuel
charcoal and gas grills
lawnmowers, snowblowers, and other gasoline powered yard equipment run in an attached garage or basement
cars, snowmobiles, trucks and other vehicles run in an attached garage
tobacco smoke

Return to Top

What are the signs and symptoms of carbon monoxide poisoning?

The early symptoms of carbon monoxide poisoning can be confused with flu-like symptoms—headache, dizziness and nausea. Breathing carbon monoxide causes these symptoms even in healthy people. It can also cause sleepiness, vision problems (including blurred vision), ringing in the ears, aching arms and legs, irregular breathing, fatigue and confusion. At very high levels, it causes loss of consciousness and death.

Breathing low levels of carbon monoxide over a few hours can have just as harmful effect as breathing high levels for a few minutes. If symptoms go away when you leave your home, but come back when you return, there may be a carbon monoxide problem in your home.

Return to Top

What are the health effects?

Nationwide, hundreds of people die from carbon monoxide poisoning every year, and thousands are treated in hospitals.

Carbon monoxide lowers the body’s ability to carry oxygen to vital organs such as the heart and brain. In general, the more carbon monoxide a person inhales, the more serious the damage that occurs. The elderly, young children, infants, fetuses, and people with anemia or heart or lung problems are more sensitive to the effects of carbon monoxide. During strenuous exercise, people are also more sensitive to the effects of carbon monoxide.

Return to Top

Are there ways to lessen the risk of carbon monoxide poisoning?

The following is a list of tips to help reduce the risk of carbon monoxide problems:

DO obtain and install a carbon monoxide detector.
DO have your heating system, including your furnace, boiler, wood stove, chimney and venting system checked and serviced at least once each year. Have your chimney cleaned as often as is necessary.
DO follow the directions that come with heating or cooking equipment.
DO have your kitchen gas stove checked and serviced at least once a year.
DO make sure that all heating, cooking, and other fuel burning devices are installed according to the company’s instructions. Follow all federal, state and local housing and building codes.
DO make sure that stove pipes and other types of vents are tightly joined, and not cracked or rusty.
DO use the proper fuel in space heaters and be sure they are properly vented to the outdoors.
DO have an outside-venting exhaust hood installed above a kitchen gas stove. Use it when cooking.

DO NOT allow engines to idle (run) in a garage that is attached to or beneath the house.
DO NOT service autos or home heating and cooking appliances unless you have the correct tools, skills, and knowledge AND unless it is allowed by law and suggested by the maker of the product.
DO NOT use a charcoal grill or hibachi in your home or garage.
DO NOT use the kitchen gas stove for heating the apartment or the house.
DO NOT allow snow or ice to pile up outside a gas appliance vent.
DO NOT smoke cigarettes, cigars, pipes or other tobacco products inside the house or apartment.

While many causes of carbon monoxide problems can be prevented, this is not true in all cases. Sometimes problems occur, such as a blocked chimney or faulty furnace or gas stove, which cannot be predicted.

The presence and amount of carbon monoxide can also be affected by how airtight your house or apartment is. If a building is too airtight, it cuts down on the amount of fresh air entering and can allow levels of carbon monoxide to build up.

Return to Top

Can carbon monoxide be detected?

Yes. Carbon monoxide detectors measure the amount of carbon monoxide in the air and sound an alarm at certain levels. Before purchasing a carbon monoxide detector for your home or apartment, be sure that it meets the requirements of Underwriters Laboratory (UL).

Return to Top

Where should a carbon monoxide detector be installed?

The Vermont Division of Fire Safety has Installation Rules and Guidelines that provide the most current information on the installation of carbon monoxide detector locations.

The requirements for carbon monoxide detectors in public buildings, including multi-family and rental dwellings, are included in the Vermont Fire Safety Code Information Sheet.

What should I do if the carbon monoxide detector alarm goes off?

If your carbon monoxide detector alarm goes off, go outside and call 9-1-1. If you need medical attention, tell the emergency responders that you suspect carbon monoxide poisoning, and follow their advice.

Once you have had your home or apartment checked, it is important to take action to correct any detected problems. If you are a tenant and you need help talking to your landlord about the problem, contact your Regional Fire Safety Office.

Return to Top