The deep freeze has many Canadians hibernating inside their homes hoping to stay warm as temperatures dip into the negatives.
While avoiding the dangers of the frigid cold, such as frostbite, there are still hidden threats in the environment — and that is the silent killer, carbon monoxide.
READ MORE: Protecting yourself from carbon monoxide
After a significant snowfall or cold snap, homeowners are strongly advised to check their heat vents for snow and ice pile up, Lewis Smith with Canada Safety Council, said.
This is because snow or ice can build up over the vent and completely block it off, meaning carbon monoxide gets trapped and heads back into the house.
WATCH: What to do about snow and ice buildup around furnace vents.
“Snow drifts over vents can be skipped by our mental process, we don’t think to check it, which is seriously concerning,” Lewis said. “Carbon monoxide can easily kill you, so anything you can do to help mitigate the risk of it getting into your living space is helpful.”
Carbon monoxide is odourless and invisible. It can give you flu-like symptoms, such as headaches, nausea and shortness of breath.
The National Fire Protection Association says a person can be poisoned by a small amount of it over a longer period of time or by a large amount over a shorter amount of time.
WATCH: Are you protected from carbon monoxide?
More than 50 people die every year from carbon-monoxide poisoning in Canada, according to the Ontario Association of Fire Chiefs. And poisoning can also spike in the winter as there are heating devices used during that time.
That is why it is so important to have a carbon-monoxide detector in your home (and on every storey), Smith stressed.
If the detector goes off, he said you should go outside and check to see if there is snow accumulating over the furnace vent or ice clogging it. You should also call 911 immediately.
“Clear the build-up of snow or ice using a shovel. The ice may be a bit more tricky and you may have to chip away at it, or you can call a professional for help,” he said.
— With files from Global News’ Rebecca Joseph