Carbon Monoxide Safety

Carbon monoxide (CO) is odourless, colourless and very poisonous. The symptoms of CO poisoning are similar to the flu but without a fever. CO poisoning stops your blood from absorbing oxygen and exposure to high levels can cause brain damage or even death.

CO can be caused by poorly maintained or malfunctioning fuel-burning appliances, damaged or blocked venting, a  blocked chimney or a car running in an attached garage.

Protect Against the Dangers of CO

Getting an annual inspection of your furnace and other fuel-burning appliances by a certified technician from a registered Heating, Ventilation and Air Conditioning (HVAC) contractor is the most important step in preventing the dangers of CO buildup.

In Ontario, if your home has a fuel-burning appliance, fireplace, or attached garage, you are legally required to install a CO alarm near all sleeping areas. These alert you to the presence of CO, giving you and your family time to escape. For added protection, install a CO alarm on each level of your home.

Always follow the manufacturer's instructions for installing, maintaining and testing the alarm and follow these guidelines:

  • When you change your clocks in the spring and fall, test your alarm and change the batteries.
  • CO alarms have a limited life. If your alarm is battery-operated, know the lifespan of its batteries and sensors. A CO alarm sounding intermittently may be a sign of a low battery or an aging sensor.

To learn more, visit the Technical Standards and Safety Authority's CO Safety website or the Ontario Ministry of Community Safety & Correctional Services’ Carbon Monoxide Alarm Portal.

If Your Carbon Monoxide Alarm Sounds

If your CO alarm sounds, or anyone in the house has symptoms of CO poisoning (similar to the flu without the fever), get outside immediately and call 911.



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