FT-SDN1 Visibility Sensor: A Reliable Tool for Measuring Tunnel Visibility

A tunnel is a passage structure built underground or inside a mountain, mainly used to connect two places and cross obstacles. It is commonly found in highway, railway, water conservancy and other projects. It provides a convenient path for transportation and logistics, especially in areas with complex terrain, effectively shortening travel distance and improving traffic efficiency.

In the tunnel environment, it is necessary to measure the internal visibility and wind speed and direction. From a safety perspective, a tunnel is a relatively enclosed space. In case of emergencies such as traffic accidents and fires, exhaust gas from vehicles and smoke from fires will accumulate rapidly, leading to a sharp drop in visibility. This will seriously hinder the evacuation of people and rescue work, increasing the risk of casualties in accidents. Wind speed and direction directly affect the air circulation in the tunnel. If the wind speed is too low, harmful substances are difficult to discharge; abnormal wind direction may cause smoke and other harmful substances to swirl in the tunnel, further worsening visibility. In terms of traffic efficiency, good visibility allows drivers to clearly judge road conditions, reducing the occurrence of traffic accidents; stable and appropriate wind speed and direction help maintain good air quality in the tunnel, providing a comfortable passing environment for vehicles and personnel, and ensuring smooth traffic.

To accurately measure visibility in tunnels, the FT-SDN1 Visibility sensor can be used. This instrument works based on the transmission principle. The transmitter/receiver and reflector are installed opposite each other, with a detection beam optical path of 6 meters. According to specifications, it can be installed on the top or side wall of the tunnel. The sensor can collect VI/CO data online, and the measurement is not affected by stray light sources, avoiding interference from the environment and vehicle vibration. It has low installation and maintenance costs, and comes with functions such as status display, fault alarm and data storage. It has multiple output modes, and is equipped with an automatic compensation function for lens contamination. It operates digitally and can provide reliable data for the monitoring system.