The SEM226VICO series Tunnel Visibility Smoke and Carbon Monoxide Detector is designed to collect VI/CO data online, providing data to traffic management departments to inform decisions regarding tunnel ventilation and road safety.
The SEM226VICO Tunnel Visibility Detector operates on the principle of transmission. The transmitter/receiver and reflector are installed opposite each other and aligned using a bracket. The highly focused beam emitted by the optical components becomes a detection beam. The installation distance is 3 meters (dual-path, actual detection optical path 6 meters). Due to dust attenuation, the receiver processes the received signal into a measurement value. According to my country’s “Specifications for Ventilation and Lighting Design of Highway Tunnels,” it is installed on the tunnel roof or sidewall.
This intelligent detector has a built-in compensation function. In the event of lens contamination, it automatically performs gain compensation, ensuring a longer maintenance cycle.




