Carbon Monoxide: The Invisible Killer

Carbon monoxide is an odorless, colorless gas that often goes undetected, striking victims caught off guard or in their sleep. More than 400 people die from unintentional carbon monoxide poisoning every year, according to the Centers for Disease Control and Prevention. More than 20,000 visit the emergency room, and more than 4,000 others are hospitalized. Get tips from the National Safety Council to keep you safe.