Carbon monoxide (CO) is an invisible, odorless and tasteless gas. It’s produced by partial fuel combustion often caused by not enough oxygen. In your residence, appliances that rely on natural gas, charcoal, wood or kerosene are susceptible. Especially if they are not working properly or have been installed wrong.
Vehicle exhaust fumes from neighboring garages, as well as poorly operating fireplaces can also be a carbon monoxide source. CO is dangerous to the body and is fatal at increased levels or with extended exposure.