Carbon Monoxide Poisoning Fact Sheet Carbon Monoxide Poisoning Fact Sheet
National Center For Enviormental Health

What’s the Problem?

Carbon monoxide, or CO, is an odorless, colorless gas that can cause sudden illness and death. Carbon monoxide is found in combustion fumes, such as those produced by cars and trucks, small gasoline engines, stoves, lanterns, burning charcoal and wood, and gas ranges and heating systems. Carbon monoxide from these sources can build up in enclosed or semi-enclosed spaces. People and animals in these spaces can be poisoned by breathing it.

The most common symptoms of carbon monoxide poisoning are headache, dizziness, weakness, nausea, vomiting, chest pain, and confusion. High levels of carbon monoxide ingestion can cause loss of consciousness and death. Unless suspected, carbon monoxide poisoning can be difficult to diagnose because the symptoms mimic other illnesses. People who are sleeping or intoxicated can die from carbon monoxide poisoning before ever experiencing symptoms.

Who’s at Risk?

All people and animals are at risk for carbon monoxide poisoning. Certain groups — unborn babies, infants, and people with chronic heart disease, anemia, or respiratory problems — are more susceptible to its effects. Each year, more than 500 Americans die from unintentional carbon monoxide poisoning, and more than 2,000 commit suicide by intentionally poisoning themselves.

Can It Be Prevented?

Yes, you can prevent carbon monoxide poisoning by taking simple precautions to make sure that:

all fuel-burning appliances are properly installed, maintained, and operated;

furnaces, water heaters, and gas dryers are inspected annually by a qualified service technician;

fireplace chimneys and flues are checked and cleaned every year;

unvented fuel-burning space heaters are used only while someone is awake to monitor them and doors or windows in the room are open to provide fresh air;

automobile exhaust systems are routinely inspected for defects; and
automobile tailpipes are routinely inspected for blockage by snow during the winter months.


Never use a gas range or oven to heat a home;

Never use a charcoal grill, hibachi, lantern, or portable camping stove inside a home, tent, or camper;

Never run a generator, pressure washer, or any gasoline-powered engine inside a basement, garage, or other enclosed structure, even if the doors or windows are open, unless the equipment is professionally installed and vented;
never run a motor vehicle, generator, pressure washer, or any gasoline-powered engine outside of an open window or door where exhaust can vent into an enclosed area;

Never leave the motor running in a vehicle parked in an enclosed or semi-enclosed space, such as a closed garage.

Knowledge is the key to preventing carbon monoxide poisoning. In most cases of unintentional poisonings, victims did not realize that carbon monoxide was being produced or building up in the air they were breathing. Carbon monoxide can be easily and cheaply detected in the home; several relatively inexpensive carbon monoxide alarms are available. Consider placing a carbon monoxide alarm on each level of your homes and in your bedrooms.