Quickly and accurately measure CO levels with easy-to-use compact meter The Fluke CO-220 Carbon Monoxide Meter makes it easy to take quick and accurate measurements of CO levels with a single compact instrument. Featuring the newest generation of electrochemical sensors; the CO-220 responds very quickly to ambient changes in carbon monoxide concentration without the use of a pump. The CO-220 is the perfect instrument for technicians and other professionals who need to measure CO levels within spaces such as industrial environments; commercial buildings; or residential dwellings where accumulation of combustion gas is possible.