It's been a frigid winter and you've likely started your car in your garage just about every morning for the last few months.
But what about the carbon monoxide levels inside your garage when your car is running? And what if you forget about your car and close the garage door?
We asked Sioux Falls Fire Rescue to test the levels.
"Our meter is telling us we're catching a level there that we're going to take action whether we're going to make sure we ventilate and we're going to find out exactly where that carbon monoxide is coming from," Sioux Falls Fire Rescue Division Chief Jeff Helm said.
Coming up in tonight's Eye on KELOLAND at 10, we're going to show you what the levels are when your garage door is open and what happens when it closes.