Before driving through the tunnel, all heavy goods vehicles go through one of two thermographic security gateways. This tool (still in the experimental phase) assists security monitoring by detecting any abnormally hot areas on a trailer truck.
Differences in atmospheric pression between the two tunnel portals create a longitudinal air flow in the structure. Should there be a fire, controlling this air flow is a decisive factor both in preventing rapid spread of smoke and in restricting the smoke to the tunnel ceiling where it can be drawn out of the tunnel. For this purpose, 24 ventilators (12 for clean air, 12 for exhaust air), spread over 6 workshops are used for tunnel ventilation. Two ducts are situated above the tunnel’s structural slab. One draws up and expels exhaust air or smoke through smoke extraction vents situated every 130 m. The second injects clean air into the tunnel via 2,860 ventilation flues situated every 4.50 m.
This ventilation system is entirely automatic, it has a total capacity of 1,500 m³/s for clean air input and 1,250 m³/s for exhaust air extraction, it is linked to the Centralised Technical Management system.
Two water tanks with capacity of 500 m³ in Italy, and 250 m³ in France supply 106 fire hydrants located every 130 m in the tunnel and on the outside platforms.
All firefighting vehicles are equipped with thermal cameras, allowing them to drive in smoke filled conditions, and with air supply circuits for the engine and the cabin. The TITAN 1 700 can be identified by its 4-wheel drive which gives it a tight turning radius; The ATLAS has an easy to operate self-regulating pump; the G270 is used as a replacement vehicle should one of the other operations vehicles break down; the water tanker has a higher water capacity.
All vehicles specifically dedicated to taking users to safety are also equipped with thermal cameras and air supply circuits for the engine and the cabin. The ORTHROS double-ended evacuation shuttle, a real "mobile shelter" which can evacuate several dozen people. Two light evacuation vehicles can be used as replacement vehicles.
Ten patrol vehicles are equipped with a fire extinguishing system (100 L water tank + foaming agent pressurised by an air cylinder at 200 bars), a cabin pressurisation system (to prevent smoke entering the cabin), 2 self-contained compressed air breathing apparatus (SCBA)… These vehicles accompany hazard goods transportation and carry out continuous surveillance patrols.
Since 2005, the tunnel has been equipped with 2 permanent stations each provided with a “Le Titan” firefighting vehicle. These advanced bases, situated 4 km from each tunnel entrance allow safety crews to divide the tunnel into three sections of approximately 4,000 m. In each station, 2 firefighters specialised in tunnel fires are posted 24 h/24, 365 days a year, on 2 hourly rotations.
The main objective is to minimise response time in order to:
Currently, over 120 employees for the two companies SFTRF-SITAF, manage traffic and fire safety in the Fréjus Tunnel.