Building Fire Evacuation Risk Assessment and Mapping Considering Safety and Travel Delays

Previous studies on building fire evacuation risk often overlook time delays caused by congestion and fire hazards. This gap is addressed by defining travel delays during fire evacuations and introducing two key metrics—delay times and the delay ratio—into the assessment framework. Furthermore, a corresponding parameter calculation method is proposed that considers the characteristics of the occupant trajectory data output from the evacuation simulation. A fire evacuation risk assessment model is developed using a university dormitory as a case study. The model integrates industry foundation classes (IFC) data and advanced technologies, thereby enhancing its applicability to large, multistory buildings. The spatial and numerical distributions of fire evacuation risk indices are subsequently mapped and analyzed in specific scenarios, with risk regions identified on the basis of predefined criteria. In this case, safe regions may incur longer travel delays, whereas unsafe regions may experience fewer delays. Notably, a relatively weak correlation is found between safety and travel delays within the identified risk regions. These findings underscore the importance of considering both safety and travel delay metrics when evaluating fire evacuation risk in buildings, highlighting the need for a more comprehensive approach that accounts for both factors in risk assessments. This research contributes to more accurate building fire evacuation risk assessments and supports the design of effective evacuation strategies and informed emergency decision making.