Customising evacuation instructions for high-rise residential occupants to expedite fire egress: results from agent-based simulation

As the possibility of safe escape is one of the most crucial aspects of a building’s fire safety features, understanding of human behaviour under fire conditions is important for a successful evacuation. Although most of today’s buildings are equipped with fire safety systems, a fire can still occur at anytime and anywhere in a building and have devastating consequences. In the last decade, researchers and practitioners have used information technology to assist with fire safety design and emergency management. Building Information Modelling (BIM) is an exemplar process whose underpinning digital technology has been helpful for fire safety design, simulation, and analysis, but there is a lack of research on how BIM-based models combined with agent-based simulations can help improve evacuation via effective navigation and wayfinding in high-rise residential buildings. Customising evacuation instructions based on BIM, simulation results and occupant location, and delivery of these bespoke instructions to occupants’ smartphones during a fire emergency is relatively novel and research is needed to realise the potential of this approach. Therefore, this study investigates how customised evacuation instructions delivered to each occupant in a high-rise residential building could result in a faster evacuation during a fire incident. The research adopted a case study building and used Pathfinder (agent-based evacuation simulation software) to simulate evacuation from this eleven-floor high-rise residential building in Cairo, Egypt. Constraining evacuees (simulated agents in Pathfinder) to take particular exit routes was used as a proxy for delivering customised evacuation instructions to actual evacuees. Simulation results show that, in general, allowing the use of lifts for the benefit of disabled occupants could lead to their misuse by able-bodied occupants; evacuees would attempt to use the first visible point of exit regardless of how crowded it is. With optimally customised instructions, the evacuation time was, on average, 17.6 min (almost 50%) shorter than when the occupant’s choice of egress route was simulated based on standard path planning factors such as route length, nearby crowds and visible hazards. With evacuation instructions sent via smartphones, occupants could exit more rapidly via alternative routes. Such bespoke instructions were shown to reduce the adverse effects of crowdedness and uneven distribution of occupants along vertical and horizontal evacuation routes on evacuation time.