Carbon monoxide (CO)

Carbon monoxide: what is it?

Carbon monoxide (CO) is a gas. It is colourless, odourless, does not irritate the throat, and has no taste—which makes it a serious threat because it can be fatal and is impossible to detect without the proper equipment.

Carbon monoxide: where is it found?

CO is emitted into the air whenever any type of fuel—wood, gasoline, heating oil, natural gas, propane, ethanol, kerosene, etc.—is burned. 

There are multiple sources of carbon monoxide emission in the home:

• Chimneys, gas-powered appliances (e.g., stoves, ovens, refrigerators), fuel-powered heating systems and water heaters;

• Motor vehicles and other fuel-burning devices (e.g., lawnmower, snowblower) if left running in a garage that is attached to the house;

• Fuel-burning devices designed for outdoor use that are used indoors (e.g., as heat or energy sources during a power outage) such as barbecues, heaters, generators, etc.;

• Tobacco smoke.

How can carbon monoxide affect my health?

When inhaled, carbon monoxide builds up rapidly in the blood, preventing it from delivering oxygen throughout the body. Even before CO is detected, exposure to it can have serious health effects, and can even kill. Its effects are as follows:

• Slight exposure results in symptoms similar to those of the flu (headaches, runny nose, eye irritation, etc.);

• Moderate exposure leads to sleepiness, dizziness and vomiting; the exposed person may also feel disoriented and confused, making it difficult to make rational decisions (e.g., leaving a building or calling for help);

• Severe exposure can cause loss of consciousness, brain damage, and even death.

What can I do to prevent carbon monoxide poisoning?

The Quebec Construction Code requires that carbon monoxide alarms be installed in residences with a combustion appliance or an attached garage, in every room or within 5 metres of every bedroom door. The package label must state that the device is compliant with the ULC-2034 standard and is certified by the Canadian Standards Association (CSA), Underwriters Laboratories of Canada (ULC).

Follow this advice:

• If the alarm is of the plug-in type, choose a model with battery backup that will keep working in case of a power outage;

• Periodically check that it the alarm is working (e.g., twice a year, when Daylight Saving Time begins and ends);

• Have all of your fuel-burning appliances (including gas cooking stoves gas- or oil-fired water heaters) and chimneys maintained annually by specialists;

• Never use a barbecue or other fuel-burning device (e.g., a lamp) indoors if it is not designed for that purpose;

• Never leave a motor vehicle or gas- red generator or tool running in the garage, if it is attached to the house.

What should I do in the presence of carbon monoxide?

If the carbon monoxide alarm sounds:

• Evacuate all occupants of the home (including pets);

• Call 9 1 1 if someone is showing symptoms;

• Ventilate the premises;

• Remove or turn off the device causing the emissions, if you can identify it;

• If need be, call the fire department (9 1 1), gas supplier, or heating contractor; return home only after the authorities have confirmed that the danger is past.