Carbon monoxide is a colorless, odorless gas that is extremely poisonous and can kill within minutes. In the US each year, nearly 500 die while as many as 20,000 visit emergency rooms for exposure primarily from poorly-maintained heating systems or gas stoves and gas-powered generators used for heat or power during storms. Comments on this video are allowed in accordance with our comment policy: http://www.cdc.gov/SocialMedia/Tools/CommentPolicy.html This video can also be viewed at http://www.cdc.gov/cdctv/