A fixed gas detector is a device that continuously monitors the concentration of specific gases in the air and alerts personnel when dangerous levels are detected.

Fixed gas detectors are used in a variety of industrial and commercial settings where hazardous gases may be present, such as chemical plants, oil refineries, and semiconductor manufacturing facilities.

Fixed gas detectors can detect a wide range of gases, including flammable gases (such as methane and propane), toxic gases (such as carbon monoxide and hydrogen sulfide), and oxygen deficiency.

Fixed gas detectors use various sensor technologies to detect the presence of target gases. Common sensor technologies include electrochemical cells, semiconductor sensors, and infrared detectors.