Comparisons of Evacuation Efficiency and Pre-travel Activity Times in Response to a Sounder and Two Different Voice Alarm Messages

Previous studies (Bellamy and Geter, 1990, BRE Report BR 172; Proulx and Sime, 1991, Fire Safety Science, 3rd International Symposium, pp. 843-852; Sime, 1998, Human Behaviour in Fire, Proceedings of the First International Symposium, pp. 299-308; Purser and Bensilum, 2001, Safety Science 38, pp. 157-182) have indicated that recorded voice alarm messages can be more efficient than sounders in motivating occupants to evacuate buildings, and that they produce shorter pre-travel activity (pre-movement) times (PTAT), sometimes by a wide margin. More recently, with increased use of voice alarms and other voice announcements, people may have become less responsive. For this study, monitored evacuations using voice alarms were conducted in a shopping centre, a theatre and a large office building (Purser and Bensilum, 2001, Safety Science 38, pp. 157-182). An experimental study was then set up in a university teaching room under hidden video surveillance, in order to examine responsiveness to different alarm systems (including a sounder, long and short voice messages) and provide PTAT data. The findings from both the monitored evacuations and the experimental study were that voice alarms provided more reliable and shorter PTAT response times than sounders, especially in "awake and unfamiliar" behavioural scenarios. Occupants tended to listen to the full voice message and sometimes the first repeat before starting to travel. The short voice message produced a shorter but less reliable PTAT response. Group interactions had a major effect on response behaviours and times.