Carbon monoxide can be a silent killer, especially in the winter when most exposures happen according to Johns Hopkins Medicine. "People are unaware of it – they go to sleep, and they don't even realize that carbon monoxide is present,

The CDC also reports that at least 430 people die each year in the U.S. from accidental carbon monoxide poisoning. Being aware of the symptoms could save your life or someone else’s. "Critical warning signs would be symptoms like headaches, nausea, fatigue, and cherry-red lips. Those would be some of the primary indicators," Zane noted.

Called “the silent killer”, carbon monoxide can be extremely dangerous and completely unrecognizable at first. Upstate Medical’s director of poison control, Vincent Calleo, gave out some helpful tips on how to stay safe.