Residents of a Glebe four-unit rooming house were evacuated after firefighters detected a fatal level of carbon monoxide on Monday morning.
Ottawa Fire Services say they were requested to respond to the 0-100 block of Ralph Street by paramedics after a medical call found possible exposure to the toxic gas.
Firefighters entered one of the homes and detected 140 parts per million (PPM) inside and dangerous readings of 330 PPM inside the basement.
Another crew detected levels as high as 999 PPM inside a second residence next to a boiler inside the basement, the highest number on their detectors, according to Ottawa fire spokesperson Nick Defazio.
Carbon monoxide at that level can be fatal within minutes, Defazio said.
Residents were evacuated and an OC Transpo bus was called to the scene to shelter them.
Ottawa paramedics say one adult male was transported to hospital with non life-threatening injuries.
Firefighters switched off the boilers of all four homes and used high-pressurized fans to bring the air quality back to a safe level.
Investigators confirmed the cause of the leak to be from the boiler inside the second home.
The scene was left in control of an Ottawa Fire Services investigator shortly before 1:25 p.m.
The incident remains under investigation.
Carbon monoxide is generally known as the ‘silent killer’ because it has no taste, colour, or smell and inhaling it can lead to serious illness or death.
If you suspect you have been exposed to carbon monoxide or if a carbon monoxide alarm goes off, the advice is to immediately get out of the building and call 911.
