When the snow flies, firefighters expect calls to pick up.
Many are for house fires, but they also commonly deal with carbon monoxide calls.
Duluth Deputy Fire Marshal Jon Otis said this year, it's especially important to have a working CO detector.
"Carbon monoxide causes flu-like symptoms. So if you're having a headache or you're feeling sick to your stomach ... those could all be indicators of carbon monoxide poisoning. It also could be symptoms of flu or even we're now experiencing COVID stuff," Otis said. "So by having a CO detector working in your home, that eliminates one of those possible potential hazards."
CO detectors should be replaced every seven years.
Heating-related fires are the third most common cause of fire in Minnesota, behind cooking and open flames.