Evacuation performance of individuals in different visibility conditions

Accurate data on evacuation activities are required under visually handicapped conditions to increase the certainty of the fire performance-based designs and evacuation calculation models. This study was to analyze human behavior characteristics and evacuation performance change through the experiments under evacuation environment where smoke influences visibility. The evacuation experiment was conducted in four different visibility conditions at underground facilities with 125 subjects. The individual evacuation activities of the subjects regarding the evacuation time, movement speed, way-finding and the evacuation routes were recorded and studied. Difference in visibility condition caused changes in evacuee's movement speed and travel distance. The change in visibility condition by indoor ordinary lights caused significant change only in movement speed on flat floors. However, the change in visibility by smoke caused significant change in travel distance as well as movement speed. These changes in evacuation performance were different, depending on the spatial characteristic.