Tunnel ventilation should ensure maintenance of harmful gases in the allowed limits, and that should be done with maximal traffic intensity, minimal driving speed and unfavorable meteorological conditions. This system must also ensure defined and approved conditions in case of fire in the tunnel.
Tunnel ventilation must attenuate combustion products (emission and hard particles) produced by motor vehicles to an acceptable level in order to prevent excessive pollution and to control spreading of the smoke in case of fire.


  • 1. TMCC
  • 2. Two-way communication
  • 3. Ventilators
  • 4. SOS niche, PLC
  • 5. CO, temperature, speed and flow direction sensor
  • 6. Fog sensor

Process sensors


Visibility – measures visibility level in a tunnel

CO – measures the level of CO gases in a tunnel

Temperature - measures temperature in a tunnel

Speed and flow - measures speed and determines flow direction in a tunnel


Fog sensor - it is located in front of the tunnel and detects decrease in visibility caused by fog

System of ventilators

This system provides manual and automatic commands for activating ventilators.

All sensors and ventilators are connected to a PLC network which is connected to TMCC.

PLCs are connected to TMCC via Ethernet network. TMCC operators control this system and have pre-programmed scenarios how to react in certain situations.

In case of too much vibration or malfunction on the ventilator motor, TMCC will receive the information about the incident and the operator will be able to choose pre-set scenario on his/her monitor.

PLC is local automatic management controller and interface for remote management.