carbon-monoxideMYTH Carbon monoxide is normally harmless, but can be dangerous at high levels.

TRUTH Carbon monoxide is a poisonous gas that is dangerous at any level. It’s created when fuels like wood, oil and gas burn. Normally, the small amounts caused by our heating equipment are vented to the outside and do not build up inside.

MYTH Carbon monoxide has a distinctive odour you can smell.

TRUTH Carbon monoxide is odourless, colourless and tasteless, which is why it’s called the “silent killer.”

MYTH Carbon monoxide problems are caused by old heating systems.

TRUTH Heating systems (furnaces, fireplaces, wood-burning stoves, and chimneys) should be checked every year by a certified heating technician before the heating season begins.

MYTH It’s ok to use a gas or charcoal barbecue or run a car in a garage as long as the garage door is open.

TRUTH Carbon monoxide poisoning has symptoms that are similar to the flu: nausea, headache, burning eyes, confusion, drowsiness, and loss of consciousness. The key difference is that there is no fever with CO poisoning. The symptoms tend to disappear when a person gets fresh air. These are all warning signs.

MYTH You should only call 911 if your carbon monoxide alarm keeps going off after you’ve opened the windows and doors.

TRUTH If anyone feels ill, get everyone, including your pets, out of the house regardless if the alarm is sounding or not. Call 911 or your local fire department for help. Once the source of the CO is found – stay out of your home until repairs are complete. If no one is ill, ventilate the building by opening all windows and doors. Reset the alarm. If it continues to sound, call a certified heating technician to check for carbon monoxide.


MYTH Certain levels of carbon monoxide can kill, but survivors can expect a complete recovery.

TRUTH Many victims of carbon monoxide poisoning recover with treatment. However, in very severe cases, CO poisoning can cause permanent brain damage.

MYTH The best way to protect against carbon monoxide poisoning is to have a CO alarm in your home.

TRUTH The first line of defense against carbon monoxide poisoning is prevention through annual inspections of your home heating equipment, including vents and chimneys. Alarms are a good second line of defense and every home should have one or more.

MYTH All carbon monoxide alarms sold in Canada are certified to Canadian Safety standards.

TRUTH Not all carbon monoxide alarms sold in Canada are certified to Canadian Safety standards. To make sure you’re buying one that is certified, look for the CSA or ULC symbols.