Carbon Monoxide (CO) is an odourless, colourless, toxic gas. It is produced when fuels (such as gasoline, wood, coal, natural gas, propane, oil and methane) are burned incompletely. In the home, heating and cooking equipment that burn fuel can be sources of carbon monoxide.

Carbon Monoxide is often called the silent killer because it has no odour. Exposure to the gas can cause symptoms such as:

  • Dizziness
  • Headache
  • Nausea
  • Fatigue
  • Burning eyes
  • Vomiting 
  • Loss of muscle control 

As there can be many other causes for these symptoms, including the flu, carbon monoxide poisoning is often difficult to diagnose. Other warning signs of carbon monoxide poisoning include:

  • Stale or stuffy air
  • Excessive moisture on windows and walls
  • Soot buildup around appliances and vents
  • A yellow flame in a natural gas appliance instead of a blue flame
  • A pilot light that keeps going out

There is an extremely low risk of carbon monoxide poisoning from regularly maintained appliances that are properly ventilated. Improperly installed or poorly maintained appliances that use fuels (gas, oil, coal, wood, charcoal, kerosene, propane or natural gas) may create unsafe levels of carbon monoxide.

Prevent Carbon Monoxide Hazards

Install and maintain carbon monoxide alarms
  • Install carbon monoxide alarms in a central location outside each sleeping room as well as on every level of the home
    • For the best protection, all carbon monoxide alarms should be interconnected so that when one sounds, they all sound 
  • Test your carbon monoxide alarm at least once a month and replace them according to the manufacturer’s instructions
  • Replace the batteries annually
  • Never remove batteries or disable alarms

Purchasing a carbon monoxide alarm
When you purchase a carbon monoxide alarm, make sure that it is certified to Canadian standards. Products with CSA 6.19-01 on the packaging have been tested to the Residential Carbon Monoxide Alarming Devices standards. The alarm will also show a replacement date.

Follow the manufacturer’s instructions for installation, proper use and maintenance. Carbon Monoxide alarms are usually installed between sleeping areas and your appliances.

Maintain fuel burning appliances
  • Review user manuals
  • Get your appliances checked annually by a qualified service technician or heating contractor
  • Use appliances only for the purpose for which they are intended
Ensure proper air flow
  • Check that chimneys, fireplaces and vents are not corroded or blocked by snow or other debris
  • Do not operate chainsaws, lawn mowers, snow blowers, gas or charcoal grills in an enclosed area such as a garage, workshop or shed
Never leave an idling vehicle in an attached garage
  • Immediately move your vehicle out of the garage after starting the engine to prevent exhaust flames from seeping into the building through connecting doors or vents