The fixed hazardous gas detection system is an instrument that adopts sensor array technology and integrates photoionization, metal oxide, non-dispersive infrared, electrochemical, catalytic combustion and other sensors to monitor and alarm the concentration of hazardous gases in the environment. The product features infrared remote control, explosion-proof certification, ultra-high sensitivity and other characteristics, and is mainly applied in new energy, petrochemical, metallurgical refining and other industries.