Carbon Monoxide Gas Detector Alarm for an aircraft, vehicle, caravans and boats. A carbon monoxide detector or CO detector is a device that detects the presence of the carbon monoxide (CO) gas to prevent carbon monoxide poisoning. CO is a colorless, tasteless and odorless gas produced by incomplete combustion of carbon-containing materials. Carbon monoxide detector will sound an alarm and light when the alarm detects a certain amount of carbon monoxide inside the vehicle.