Carbon monoxide (CO) is a highly poisonous gas, often referred to as ‘the silent killer’ because you can’t see it, touch it or smell it.

This odourless gas is produced as a byproduct of combustion when common fuel-burning appliances and equipment that use natural gas, oil, wood, propane and kerosene, don’t get enough air to burn up completely.

When this happens, CO can build up, especially in a confined room or space – and this can lead to toxic effects on humans and pets.

Most of these sources are associated with malfunctioning fuel-burning equipment and appliances – and poor venting and confined spaces, like a furnace room, garage, cabin, tent, RV, boat cabin or camper.

While carbon monoxide doesn’t have an off-season, it certainly has a major presence in the summer, when many of us are dealing with certain fuel-burning equipment that we use on a seasonal basis.

Of course, the cooler seasons often keep us indoors, and confined spaces, poor venting or limited air-flow also contribute to the CO hazard.

Common Sources of Carbon Monoxide

Most Ontario households have, on average, 4-6 appliances that produce carbon monoxide.

These appliances include:

• Furnace
• Gas water heater
• Gas fireplace
• Gas stove
• Gas dryer
• Gas barbecue
• Portable generators
• Fuel-burning space heaters

Poor maintenance/Improper venting
Poor maintenance of these appliances, damaged or blocked venting, or inadequate airflow can cause dangerous levels of CO to build up inside your home, garage, cottage – virtually any enclosed space under certain conditions.