Carbon monoxide (CO) is an invisible, odorless and tasteless gas. It’s produced by partial fuel combustion usually caused by not enough oxygen. In your house, appliances that rely on natural gas, charcoal, wood or kerosene are vulnerable. Especially if they are not operating properly or have been installed incorrectly.
Vehicle exhaust fumes from neighboring garages, as well as poorly operating fireplaces could also be a carbon monoxide source. CO is poisonous to the body and is lethal at high levels or with prolonged exposure.