Calgary fire crews responded to multiple carbon monoxide alarms Thursday across the city.
At 11:30 a.m., fire crews were called to a 48-unit residence at 4975 130 Ave. S.E. by a number of residents whose alarms had gone off.
Crews discovered the CO levels were at 200 parts per million (ppm) in the lobby and as high as 520 ppm in the hallways and common areas of the building.
Crews activated fire alarms and everyone in the building was evacuated to a nearby building. ATCO was called to the scene to investigate. It was discovered that a vent was blocked with leaves and other debris that had iced over, causing the CO buildup.
Once the blockage was removed, the building was reventilated and residents were allowed to re-enter their suites.
Earlier in the day, just after midnight, a northeast Calgary family’s carbon dioxide alarm went off, causing them to call …