Tunnel monitor

The VICONOX tunnel monitor is a single sensor solution for measuring toxic gases (NO2, NO, (NOx), CO), visibility and temperature within harsh road/rail tunnels and confined environments.

Measurement data can be used as part of a ventilation control air quality management system and/or secondary smoke detection.



  • Measures up to 6 parameters, minimising capital cost, cabling, installation & commissioning
  • Pre-aligned quick release TX & RX heads for easy installation & maintenance
  • Temperature & humidity compensated measurements for stable readings across all conditions
  • Rugged, anti-corrosive design & 316 stainless steel construction for long service life
  • High quality, IP67-rated external enclosure with quick release dust protection tubes
  • Intelligent heads with RS485 (Modbus RTU), digital relays & analogue outputs as standard
  • Connects to PLC / SCADA system