The frigid temperatures caused an incident in a residential highrise Tuesday morning, when it had to be evacuated following the discovery of elevated carbon monoxide readings in one unit.
The incident took place shortly after 8:30 a.m., when emergency crews were called for a person reporting breathing problems in a building on Horton Road S.W..
While the call related to a person with a pre-existing condition, the attending fire crew's portable gas monitor was activated, indicating carbon monoxide levels of greater than 183 parts-per-million.
Firefighters relocated the patient to the lobby in his wheelchair, where he was met by EMS and escorted to hospital.
The building was then evacuated of approximately 150 people on a day when the wind chill was approximately -38, which was mitigated by a number of Calgary Transit buses brought to the scene.
Subsequent investigation of suites from floor to floor throughout the building revealed consistently high levels of carbon monoxide, which is colourless, odorless, tasteless, non-irritating — and potentially lethal.
Levels as high as 400 parts-per-million were discovered in some areas of the building, while a number of carbon monoxide alarms in various suites were beeping.
Investigation of the building found a fresh air intake on the roof had frozen over, creating a buildup of carbon monoxide in the building.
Firefighters were able to open the intake, ventilate the building and residents were allowed back in their suites once carbon monoxide readings were back to zero.
No injuries were reported.
The fire department reminds Calgarians to ensure you have working smoke and carbon monoxide alarms on every level of your home and to ensure your furnace and exhaust vents are free of snow and ice.