Parkade cleaning, poor ventilation prompts carbon monoxide alarm at NW Calgary apartment building

An inadequate HVAC system combined with parkade cleaning prompted the evacuation of a northwest Calgary apartment building due to carbon monoxide Wednesday evening, the Calgary Fire Department (CFD) says.

Firefighters were called to the area of 2 Avenue and 19 Street NW in West Hillhurst just before 6 p.m.

Crews detected carbon monoxide levels as high as 100 parts per million within the building.

Sixty people were evacuated as a result. Five of those individuals were taken to hospital for assessment, and a baby was taken to the Alberta Children’s Hospital by their parents.

The alarm was initially raised by a building tenant whose CO alarm was activated in her unit. The CFD says she called 911, which was the right thing to do.

The department is emphasizing the importance of working carbon monoxide alarms, which can give an early warning of the invisible, odourless, and dangerous gas, ultimately saving lives.

ATCO Gas was called to the scene to investigate whether gas-burning appliances were a contributing factor to the CO build up.

Crews later determined the building’s parkade had been cleaned with a piece of gas-powered equipment and that inadequate building ventilation was to blame.

CFD had a HVAC technician come to the building to inspect the ventilation system and make sure it was working properly after the issue was discovered.

Using gas-powered equipment or appliances such as pressure washers, heaters, or generators in enclosed or poorly ventilated spaces is extremely dangerous, the department explains, adding these devices can quickly produce lethal concentrations of carbon monoxide, even if only used for a short time.

Fire crews ventilated the building and went through floor-by-floor to confirm CO levels had went back to zero.

Once the air quality was deemed safe, residents were allowed to go back into their units.

The scene was cleared by CFD around 8:30 p.m.

Symptoms of CO gas exposure include headache, nausea, dizziness, confusion, fatigue, and loss of consciousness.