VIPA-L Tunnel Sensors

The VIPA-L Long Path Visibility Monitor makes a visible opacity measurement to determine the average visibility along the sight path of the instrument, within an ambient environment such as road, rail, meteorological or other industrial application. These measurements can be used as part of an air quality management system.


  • Designed for in-situ monitoring of ambient environments
  • Visibility measurement using the widely accepted single pass light transmission opacity technique, over a path length of up to 20m
  • User selected unit display options of Opacity (%), Extinction Coefficient (k), Meteorological Optical Range (MOR) or Transmission
  • Low detection limits for dust and particulate
  • Integrated temperature and humidity monitoring
  • Intelligent analyser with optional TSCU operator interface


  • Rugged design to withstand ambient and atmospheric weather conditions
  • IP65 / NEMA 4X rated external enclosure supplied with quick release site tubes and integrated mounting brackets
  • Plug and socket cable connection enabling simple installation
  • No moving parts and low maintenance requirements
  • Choice of interface options enabling easy integration into any data monitoring or control system


For further information and technical specifications about this product please download a product brochure alternatively contact us via phone or email and a member of our team will be happy to help.

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We think of tunnel sensors as one of our most reliable and valuable partners that can provide equipment and technical expertise of highest quality.

Vassilis Moustaferis
New Alert ICT Systems, Greece

Tunnel Sensors



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The AIRFLOW offers a rugged, non-contact solution for the universal requirement to monitor air velocity and direction in the tunnel.


The VICONOX provides a total monitoring solution
for the measurement of NO2, NO, CO, visibility
and temperature within traffic tunnels.