Structural Fire Protection in Tunnelling

Transportation facilities such as tunnels are subject to strict requirements and extensive quality inspections. On average, the frequency of accidents in tunnels is lower than outside of tunnels because of defensive measures for the prevention of accidents such as speed limits or restriction on overtaking. Tunnel roads are also not exposed to weather conditions such as snow, ice etc. However, this is contrasted by the fact that the extent of a fire in a tunnel is usually considerably more severe than on the open road.

Maintenance of performance of electrical security systems

The fast and safe evacuation of people in the event of fire requires that all relevant safety equipment is not impaired in its function. For the most part, road tunnels are therefore equipped with electrical wiring systems (cables + distribution boards) that are used, in addition to the general supply of power, for the power supply of safety-related systems inside the tunnel that must maintain its function for a certain period of time (maintenance of performance 90 min) in the event of a fire (e.g. night-time illumination / emergency lighting / fire emergency lighting, smoke extraction, extinguishing devices, etc.). The greatest potential fire hazard comes from vehicles on the roadway. But the general power supply may also adversely impact safety-related systems or even stop them from functioning in case of its malfunction with a consequential fire.

The consistent use of standardized fire protection products with national technical approval eliminates these risks to a large extent and thus guarantees a higher level of security in the overall security concept of road tunnels.

Separation of fire and smoke zones

Rescue routes must be kept smoke-free. This can be achieved with locks or positive pressure ventilation. Escape and rescue routes must be separated in terms of fire protection so that each tube, each rescue tunnel and every rescue shaft can be classified as an individual fire zone.