Carbon monoxide (CO) is a colorless, odorless and tasteless gas. It’s produced by insufficient fuel combustion frequently caused by not enough oxygen. In your house, appliances that need natural gas, charcoal, wood or kerosene are at risk. Especially if they are not working properly or have been installed wrong.
Vehicle exhaust fumes from nearby garages, as well as malfunctioning fireplaces can also be a carbon monoxide source. CO is toxic to the body and is fatal at heightened levels or with extended exposure.