Carbon monoxide (CO) is a colorless, odorless and tasteless gas. It’s created by insufficient fuel combustion frequently caused by a lack of oxygen. In your house, appliances that need natural gas, charcoal, wood or kerosene are susceptible. Especially if they are not working properly or have been installed wrong.
Vehicle exhaust fumes from attached garages, as well as fireplaces that aren’t working right can also create carbon monoxide. CO is dangerous to the body and is lethal at increased levels or with extended exposure.