Carbon-monoxide detector, also called a CO detector, is a device designed to monitor levels of carbon monoxide inside homes. The device makes a loud, piercing sound when carbon monoxide reaches potentially unhealthy levels.
There are three types of CO detectors, biomimetic, semiconductor, and electrochemical. A biomimetic detector contains a light source that shines through a chemically treated disk called a gel cell. The cell absorbs carbon monoxide, which causes it to darken. When the cell darkens enough so that light cannot pass through it, an alarm sounds.
In semiconductor and electrochemical detectors, a computer chip monitors the flow of electric current through a substance. This substance is a solid in semiconductor types and a liquid in electrochemical types. When the substance reacts with carbon monoxide, its resistance to the current changes. The computer chip detects the change and causes the alarm to sound.
Manufacturers began making residential CO detectors in the early 1990’s. CO detectors are produced as battery-operated or plug-in models. Some devices include both a CO detector and a smoke alarm. Safety experts recommend the installation of at least one detector near the bedrooms in all homes.
