A carbon monoxide leak near downtown London has sent four people to hospital.
Firefighters were called to the multi-unit home on Simcoe Street east of Colborne Street around 9 a.m. on Tuesday.
High levels of the deadly gas were found inside the home, with the highest readings coming from the boiler room, according to Assistant Deputy Fire Chief Gary Bridge.
While most of the tenants were able to escape before crews arrived, firefighters helped those still inside get out safely.
Paramedics assessed six people at the scene, with four of them needing to be taken to hospital for further treatment.
Sixteen tenants have been temporarily displaced by the leak.
"No one will be allowed back in the building until the boiler is serviced... hopefully sometime before the end of the day," said Bridge.
Enbridge Gas crews were on scene by 10:30 a.m.
Carbon monoxide is considered the "silent killer" because it has no smell or taste. Exposure to it can cause flu-like symptoms including headache, dizziness, drowsiness, nausea, breathlessness, collapse, loss of consciousness, and death.
"All homes with fuel-burning appliances or attached garages in Ontario are required to have CO alarms adjacent to all sleeping areas, as well as in the service room," said Bridge.
Failure to comply with the CO alarm law, which came into effect in 2014, can result in a fine ranging from $360 to $50,000 for individuals and $100,000 for landlords.
Emergency crews on scene of a carbon monoxide incident in the 400 block of Simcoe Street. High levels of carbon monoxide in the boiler area. Seven individuals treated on scene and transported by @MLPS911 Ventilation underway and @enbridgegas on scene. #ldnont @ONFireMarshal pic.twitter.com/JDOizRxaIy
— London Fire Department (@LdnOntFire) February 20, 2024