3. Detection and warning

3.1 Fire detection

• Tunnels without permanent human supervision

  An automatic fire detection system must be installed when the ventilation system to be used in the event of fire is not the same as that to be used in the event of heavy air pollution in the tunnel. It must automatically switch on the ventilation regime applicable in the event of fire, and trigger an alarm in the department on duty.

• Tunnels with permanent human surveillance

  The usefulness of an automatic fire detection system needs to be considered in relation to the volume of traffic, particularly heavy goods vehicles, and in relation to other equipment required for this surveillance and...