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Carbon monoxide is a colourless, odourless gas that is a by-product of combustion. Continued exposure of exposure to high levels of carbon monoxide can result in severe headaches, breathing problems, cardiac complications, dizziness, confusion and, ultimately, death.

The Canadian Safety council has recently reported that 200 Canadians are killed each year by carbon monoxide poisoning and another 1,500 are exposed to high enough concentrations that they need medical attention.


1.  The exhaust from an automobile.
2.  Solid or fossil fuel burning appliances in your home such as furnace, gas
     or oil hot water heater, a fireplace, wood stove or gas range.


1.  A crack or other defect in the heat exchanger in your furnace or boiler will allow carbon monoxide to exit the combustion chamber and vent into the living space of your home.
2. A blockage in the chimney or flue of any fuel burning appliance will restrict the discharge of combustion gases (including carbon monoxide) to the exterior and cause spillage into the living space.
3. A defect in the house ventilation system may cause a negative pressure inside the house. This can actually draw carbon monoxide and other noxious gases from the flue back into the house.

  • Have your furnace or boiler checked every year. Make sure the checkup includes an inspection of the heat exchanger and the condition of the flue interior.
  • If you have a garage attached to your house, make sure the connecting door has a weatherproof gasket and a self-closing device. seal any openings in the garage walls or ceilings common with the house. Do not operate your automobile for prolonged periods of time.
  • Make sure there are no vents or inlets on the driveway side of the house that may inadvertently allow fumes from a running vehicle to enter the house.
  • Install a carbon monoxide detector near the bedrooms. Some people may want to install one detector at each floor level.
  • Install a cap at the top of on any flues that service a furnace, wood stove, fireplace, etc. in order to keep birds and other wildlife from nesting in the chimney flue.
  • Your carbon monoxide detector(s) may be connected in series with your smoke alarms or your security system. If either detects a problem, the alarm will be activated. Remember, just as with a fire, when the alarm goes off you must exit the house immediately and call the fire department.