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Poison Center Helpline 1-800-222-1222


What Is Carbon Monoxide?

Carbon monoxide (CO) is a poisonous gas. You cannot see, taste or smell carbon monoxide. It is released when fuels such as wood, oil or gasoline, are not burned completely.

Common Sources of CO

  • Oil, wood or gas furnaces
  • Gas stoves or dryers
  • Gas space heaters
  • Gas or oil water heaters
  • Gasoline-powered vehicles and tools such as lawn mowers, snow blowers, chain saws and weed-eaters
  • Charcoal grills
  • Candles and gas lanterns

These appliances emit CO during regular use, and it may become a problem when there is a leak from the vent that carries CO out of the home, or when an appliance or a piece of equipment malfunctions or is poorly ventilated.

Portable generators are also a source of carbon monoxide. Although mostly used during power outages, generators are also popular for camping and other outdoor activities.

Prevention Tips

  • When you run a gas powered lawn mower or tool, make sure there is good air flow.
  • Use charcoal and gas grills only in places where air flows freely.
  • Never let your car run in the garage, even if the garage door is open.
  • Do not sleep in a parked car while the engine is running.
  • Have your car's exhaust system inspected for leaks.

CO detectors are another way to protect your family from being exposed to dangerous levels of CO gas. CO detectors function like smoke detectors to warn you before CO concentrations reach dangerous levels. Every home in Illinois is required by law to have a carbon monoxide detector. Visit the Consumer Product Safety Commission website for more information on CO detectors.

Signs and Symptoms

Early symptoms of CO poisoning — including headache, nausea, vomiting and dizziness — can mimic the flu or other illnesses. More significant poisoning symptoms also can include:

  • Throbbing headache
  • Drowsiness
  • Confusion
  • Heart irregularities

Severe poisonings can cause convulsions, unconsciousness, brain damage and even death. CO poisoning usually occurs slowly over a period of several hours; however, at very high concentrations, CO can kill in minutes.

First Aid Steps

If you think someone may have been exposed to carbon monoxide, fresh air is the most important treatment. Open the windows wide and help the victim outside. Once you are out of immediate danger, call IPC at 1-800-222-1222 for treatment advice.