Carbon Monoxide, (CO)

A highly toxic, flammable, colourless, odorless gas that is predominantly a product of incomplete combustion, and produced on a large scale as a precursor for the production of many other compounds. Carbon monoxide is detectable with colorimetric detection tubes and dedicated electrochemical cells. It is not detectable using a PID instrument. A carbon monoxide sensor is optional in almost all gas detectors with space for electrochemical sensors. Care should be taking with the carbon monoxide electrochemical sensor, as it is generally very cross-sensitive to most carbohydrates. An activated carbon filter is used to circumvent this cross-sensitivity, but that filter wears out even when not in use, by which time the instrument will report false-positives on carbon monoxide.