Tunnel Fire Investigation II: The St Gotthard Tunnel Fire, 24 October 2001

This paper is an abbreviated translation of part of the official report on the investigation of the fire in the St Gotthard Tunnel that occurred on October 24, 2001. The main objectives of the investigation were to: (1) determine the origin and the cause of the fire that occurred after the collision of the two heavy goods vehicles; (2) carry out all the examinations necessary to establish the dynamics of the disaster according to the nature and quantity of fuels present in the incident zone as well as the geometry of the site; and (3) explain the mechanisms of the explosions that were observed by the firemen during their fire-fighting activities in the tunnel.