Calgary, AB,

Calgary Fire Crews Respond to Multiple Carbon Monoxide Incidents

At approximately 1:00 p.m. on Wednesday, December 01, 2021, Calgary fire crews were called to a seven story residential building at the 800 block of 12 Avenue S.W. with businesses also located on the ground floor. 9-1-1 was called due to the activation of a resident’s carbon monoxide (CO) alarm. The CO alarm, located inside a suite on the second floor, was showing levels of approximately 120 parts per million (ppm). The resident was advised to evacuate immediately and wait for firefighters outside.

When fire crews arrived on scene, they found levels of CO ranging from 20-30 ppm in the corridors of the residential portion of the building and up to 100 ppm in a restaurant located on the ground level. Upon further investigation, the restaurant was found to have a malfunctioning hood fan since Tuesday, November 30th. This resulted in exhaust gasses not being properly cleared from the building, thus accumulating at an overhang and being drawn back in through the building’s ventilation system, causing a build-up of CO.

No injuries were reported as a result of this incident and it is thanks to the resident who had their own working CO alarm which alerted them to the danger. They then took the right action by calling 9-1-1 and evacuating.

Fire crews called ATCO to the scene and the cause of the CO build-up was verified. Firefighters ventilated the building to bring the levels of CO to zero. The restaurant has been instructed to not use the stove/grill until the hood fan has been properly repaired.

At approximately 13:35, fire crews were called to the 2000 block of Home Road N.W for another CO incident. A CO alarm had activated showing 60 ppm in the house. The attached home, a three-year-old duplex, had working CO alarms which promptly activated and alerted the resident to the danger. Fire crews met the homeowner outside and investigated for the source of the CO. ATCO Gas was also called to the scene.

Firefighters and the ATCO representative determined the source of the CO build-up to be the furnace exhaust which was placed too close to the fresh air intake during construction of the house.  Fire crews ventilated the home and advised the homeowner to have repairs done in order to prevent future occurrences. No injuries were reported thanks to early detection by working CO alarms.

Carbon monoxide (CO), also known as the invisible killer, is a poisonous gas that has no colour, smell or taste. You can be poisoned by a small amount of CO over a longer period of time or by a large amount of CO over a shorter amount of time. If you are exposed to CO, you may become sick, unconscious, suffer brain damage or even die. Symptoms of exposure include confusion, fatigue, headaches, nausea and dizziness.


Sources of CO gas in your home can come from a car left running in an attached garage, your furnace, hot water tank or any household appliances which run on fuels such as natural gas, propane or wood. Make sure your vents for the dryer, furnace, stove, fireplace and other fuel-burning appliances are always clear of snow and other debris. Install at least one carbon monoxide alarm on every level of your home, including the basement, and particularly, have one in or near your bedrooms.

As the Calgary Fire Department has witnessed on many occasions, working smoke and carbon monoxide alarms can be the difference between life and death. For more information on carbon monoxide safety, including symptoms of exposure, how to test and maintain alarms and how to prevent CO build-up in your home, please click here.