Carbon Monoxide Information

Carbon monoxide (CO) is a colorless, odorless, deadly gas that is a by-product of incomplete combustion. CO can form in homes when there is not enough fresh air for complete combustion of fuel.

What are sources of CO?

  • Furnaces
  • Wood burning stoves 
  • Water heaters 
  • Motor vehicle exhaust 
  • Fireplaces 
  • Gasoline-powered engines 
  • Gas appliances 
  • Charcoal-burning barbecue grills 
  • Kerosene heaters and appliances


What may cause CO levels to increase?

  • Fuel-burning appliances and other equipment that are not functioning properly or are not adequately vented may cause a build up of CO.
  • Air-tight, energy-efficient homes meant to keep warm air in during winter months and cool air in during summer months may also trap CO inside. 
  • Cracked furnace heat exchanger 
  • Blocked vents and chimneys 
  • Disconnected or corroded vents 
  • An inadequate air supply for fuel-burning appliances can cause down-drafting which may force CO contaminated air back into the home.


What are the signs of CO poisoning and build up?

  • Sleepiness
  • Headaches 
  • Dizziness 
  • Blurred vision
  • Nausea 
  • Flu-like symptoms


What are signs that a fuel-burning appliance is not receiving enough fresh air for combustion?

  • Excessive humidity in the house indicated by heavily frosted windows
  • Peculiar, stale odor 
  • Burning eyes when an appliance is operating 
  • Fireplace that doesn't draw properly


How do you prevent CO build up?

  • Make sure that your fuel-burning appliances are in good operating condition and are properly vented with an adequate fresh air supply.
  • Never use a charcoal barbecue grill inside your home or garage. 
  • Never run an automobile inside of a garage. 
  • Perform annual maintenance checks on your home's ventilation systems. Check fireplace, clothes dryer, space heaters and chimney. 
  • Have your furnace inspected annually.


Why should I buy a CO detector?

CO detectors are the only way to detect dangerous levels of CO in your home. Ideally, you should have one CO detector for every level of your home. Ensure that a detector is placed near sleeping areas.


What features should I look for when I select a CO detector?

  • The Underwriters Laboratory (UL) symbol. This symbol means that the detector has met the recommended safety standards of the American National Standards Institute.
  • CO detectors with an audible alarm. 
  • AC/DC powered detectors. This type of detector will provide coverage during a power outage. 
  • CO detectors that have a digital readout. This will allow you to determine how you should respond. A high readout requires immediate evacuation of the home and possibly medical attention. A lower reading gives you the opportunity to contact your utility company.


What should you do if your CO detector sounds?

  • Assess the health of the people in the house.
  • If there appears to be no immediate health hazards, call your utility company or an appliance repair service. 
  • If anyone is experiencing symptoms of CO poisoning, get the person out of the house and call 9-1-1 immediately. 
  • Open windows. 
  • Consider leaving the home until assistance arrives, to avoid the potential for CO poisoning.