Movement speed and exit choice in smoke-filled rail tunnels

An evacuation experiment including 100 individuals was performed inside a tunnel in order to study the effectiveness of different way-finding installations and to collect data on movement speeds and human behaviour. The participants took part in the experiment individually, and no group interactions were studied. The experiment tunnel was 200 m long and an emergency exit was located 180 m into the tunnel. In addition, emergency signs including distances to nearest exits were located every eight meters on both sides of the tunnel. The tunnel was filled with artificial smoke and acetic acid, which produced a mean light extinction coefficient of 2.2 m(-1). Participants had been told that they would participate in an evacuation experiment, but they had not been informed about the layout of the tunnel or the technical installations. The average movement speed was found to be approximately 0.9 m/s, independent of tunnel floor material examined. The experiment also demonstrated the importance of the emergency exit design. A loudspeaker, which provided people with an alarm signal and a pre-recorded voice message, was found to perform particular well in terms of attracting people to the exit, independent of which side of the tunnel the participants were following. (C) 2013 Elsevier Ltd. All rights reserved.