Industrial fixed-gas alarm systems consist of alarm controllers and detectors. The controller can be placed in the duty room, primarily controlling monitoring points. The detectors are installed at locations where gases are most likely to leak, featuring a core component of an internal gas sensor that detects the concentration of gases in the air. The detector converts the detected gas concentration into an electrical signal, which is then transmitted through cables to the controller. The higher the gas concentration, the stronger the electrical signal. When the gas concentration reaches or exceeds the alarm point set by the alarm controller, the alarm emits an alarm signal and can activate external devices such as solenoid valves and exhaust fans to automatically eliminate hazards.

The portable gas detector is handheld, allowing staff to carry it with them to check gas concentrations at various locations. This portable gas detector combines the controller and sensor into a compact and flexible unit. The main difference from fixed gas alarms is that the portable gas detector cannot be connected to other devices externally.