Tunnel fire suppression

There is increasing worldwide interest in the issue of fire suppression in tunnels, as a means of controlling the risks posed by fires to human lives, tunnel infrastructure and transport network integrity. The initial circumspect approach by standards organisations such as NFPA and the World Road Organisation (PIARC) has given way to an acceptance that fire suppression systems can provide a safety benefit, albeit under certain conditions (e.g. provision of sufficient water density and accurate/responsive fire detection systems) and subject to benefit/cost considerations. A range of fire suppression systems are available for specification, including low pressure deluge and high-pressure mist systems.

We have been involved in major studies and engineering work related to tunnel fire suppression, including the New Tyne Crossing in the UK and the Yas Island Southern Crossing Tunnel in Abu Dhabi. In each of these two tunnels, our quantitative risk assessments indicated a net benefit of selecting a fire suppression system, and these assessments were accepted by other project stakeholders and implemented into the construction.