Fires in tunnels are a major hazard to human life and can cause costly damage to surrounding infrastructure. Limited escape facilities and difficulties encountered by intervention forces gaining access to an emergency in a tunnel demand extensive safety arrangements which must also be complementary and mutually coordinated.

Tunnels and underground transport facilities are important means of communication, not only in terms of shorter journeys but increasingly for consideration of the local population and the environment. Generally speaking, important underground transport links are expected to be available without any restrictions and to operate smoothly round the clock. Interruptions due to accidents, technical malfunctions or maintenance work quickly cause traffic jams and delays, and figure in transport policy statistics as economic losses.