Alternative propulsion technologies, including battery-electric vehicles, are becoming increasingly prevalent. Whilst such vehicles remain a small overall proportion of the vehicle fleet, the combined impact of. ••Full scale fire tests of battery electric vehicles in road tunnels under real. BEV Battery Electric VehicleHF Hydrogen FluorideHRR max, avg. As the topography of Austria is relatively mountainous, fire incidents in road tunnels are of particular interest. As of January 2020, motorways and expressways in Austria included. 2.1. Test facilityAll experiments were conducted at the tunnel research facility Zentrum am Berg. This totally new research and training facility consists o. 3.1. Vehicle fires3.2. Fire fightingOne or more attempts were made to extinguish the fire in all of the BEV tests. Water was always the main extinguishing agent used. How. The increase in the number of vehicles with alternative propulsion technologies in road tunnels is expected to change the nature of tunnel safety risk. Currently, battery electric vehicles are bec.