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Carbon monoxide

About carbon monoxide

Carbon monoxide (CO) is a colorless, odorless, tasteless, invisible gas that can be formed when fuels like charcoal, coal, gasoline, kerosene, natural gas, oil, propane or wood are burned without a sufficient supply of air.

Carbon monoxide detector

  • Install a carbon monoxide detector with an audible alarm in your home and garage.
  • Carbon monoxide detectors should meet Underwriters Laboratories, Inc. standards, have a long-term warranty, and be easily self-tested and reset to ensure proper functioning.
  • For maximum effectiveness during sleeping hours, carbon monoxide detectors should be placed as close to sleeping areas as possible.


Exposure to carbon monoxide reduces the blood’s ability to carry oxygen. Breathing low levels of carbon monoxide can cause fatigue and increase chest pain in people with chronic heart disease. Breathing higher levels of carbon monoxide causes flu-like symptoms such as:

  • Headaches
  • Dizziness and weakness
  • Sleepiness
  • Nausea and vomiting
  • Confusion and disorientation
  • Muscle weakness or fatigue

At very high levels, carbon monoxide causes loss of consciousness and death.

If the flu-like symptoms are NOT accompanied by fever, or if everyone in the family is ill, or if the symptoms disappear when you leave the house, you may have a carbon monoxide problem. Prevention is the only way to deal with carbon monoxide, and the best prevention is regular inspection by a trained service technician.

If you think someone is suffering from carbon monoxide poisoning, get the person into fresh air immediately and call 911 for emergency help. Be sure to open doors and windows to ventilate the area.


Natural gas furnaces and heating products such as fireplace logs and space heaters should be inspected every year. Other appliances, such as water heaters, clothes dryers, ranges and cooktops, should be checked for proper operation every two years.


Any fuel-burning appliance that is not adequately vented and maintained can be a potential source of carbon monoxide, including:

  • Gas appliances (furnaces, ranges, oven, water heaters, clothes dryers, etc.)
  • Fireplaces, wood and coal stoves, space heaters
  • Charcoal grills, automobile exhaust fumes, camp stoves, gas-powered lawn mowers, and power tools

An appliance could produce carbon monoxide if:

  • Boxes, laundry or other materials are blocking the base, restricting airflow.
  • The vent hood, pipes or flues are blocked or corroded.
  • The unit is installed or adjusted improperly.
  • It’s used incorrectly (i.e., heating a room with a gas stove or using a gas or charcoal grill indoors).
  • The heat exchanger is cracked.

The most common sources of carbon monoxide accumulation in the home include:

  • Blocked chimney opening
  • Improperly operating fuel burning appliances
  • Disconnected, corroded, or blocked appliance vent pipes
  • Cracked furnace heat exchangers
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