Quantitative Simulation of Human Evacuation Dynamics under Visibility Impairment in Indoor Fire Scenarios

Abstract

This study quantitatively analyzes the impact of visibility degradation caused by smoke spread on human evacuation behavior during indoor fires. Hence the reaction-based evacuation model outlined in the New Zealand Fire Safety Verification Method (C/VM2), simulations were conducted to observe how evacuees respond under conditions of gradually decreasing visibility due to increasing smoke concentration. Specific behavioral changes were examined, including Response Time, Route Selection, Avoidance Behavior, and Situational Awareness. For the purpose of this study, an indoor environment was modeled, and smoke spread was visualized to design an evacuation model that reflects visibility constraints. The analysis revealed that once smoke concentration exceeds a certain threshold, evacuees face significant visual impairment, leading to delay in evacuation and increased risk of collisions. Furthermore, the Presence of Smoke Control System, the Status of Door Opening, and the Configuration of Evacuation Route were found to be closely related to visibility during fire events. It emphasizes the importance of incorporating visibility-based strategies into evacuation planning alongside physical architectural considerations in performance-based fire safety design. It also suggests the potential for integrating psychological response factors and AI-based predictive systems in future research.