Detection, Opacimeters and Ultrasonic Anemometers.
The tunnel D’Envalira is a toll tunnel which connects the towns of Grau Roig and Pas de la Casa. It was built in 1999 in order to facilitate the circulation of vehicles and avoiding driving through the Envalira pass, where we find more than 8% gradients.
The tunnel is in Andorran territory but the eastern entrance (Pas de la Casa) is done through a viaduct in French territory. This tunnel connects the General II road of the Principality of Andorra with the Route Nationale 22 of France. The D’Envalira tunnel, which is located at an altitude of 2050 meters approximately, it is one of the highest tunnels in Europe.
The installation already has a DURGAS system of Durán Electrónica, but recently it has been completed with new CO and NO2 EURODETECTORS, manufactured and also designed by Durán Electrónica. In addition, Opacimeters and ultrasonic anemometers distributed by Durán Electrónica have been installed.