A LaSalle elementary school will reopen two days after a carbon monoxide leak sent 35 children and eight adults to hospital.
The Marguerite-Bourgeoys School Board confirmed Ecole des Decouvreurs will resume a regular schedule on Wednesday.
Heating and furnace service crews were sent to the school Tuesday to repair a problem with the school’s heating system. It's not known how long the system had been leaking carbon monoxide into the school.
“This could have been something going on for a couple of days, where these kids were exposed to it,” Ian Ritchie, an operations chief for the Montreal fire department, told CTV Montreal.
Tests showed levels of the toxic gas in the school were 90 times the acceptable level for a home.
"It was found up to 900 parts per million in some parts of the school," Ritchie said. "That was in the room itself where the heating system was, but now it distributes throughout the school."
CO levels of 175 parts per million were registered in the school's hallways.
A carbon monoxide concentration of 35 ppm is considered unsafe and would be enough to evacuate a building.
As of Tuesday all but one child who were originally admitted to hospital had been sent home. Two other children who arrived in emergency rooms afterwards were kept for observation.
The Marguerite-Bourgeoys School Board said it would inspect all of its schools to following this week's incident.
While carbon monoxide detectors are not required in Quebec schools, Ecole des Decouvreurs did have one and it was inspected as recently as October. What caused the device to fail Monday is not clear.