Carbon monoxide (CO) is an invisible, odorless and tasteless gas. It’s made by incomplete fuel combustion frequently caused by a lack of oxygen. In your house, appliances that use natural gas, charcoal, wood or kerosene are susceptible. Especially if they are not working properly or have been installed improperly.
Vehicle exhaust fumes from neighboring garages, as well as malfunctioning fireplaces can also produce carbon monoxide. CO is poisonous to the body and is deadly at heightened levels or with prolonged exposure.