Characteristics of merging occupants in a staircase

The purpose of this study was to investigate the effects of mergence of crowds in a staircase and the ease of merging with variations in crowd density,directions of mergence,and whether the door connecting a hallway to a staircase was opened or closed.The results led to the following conclusions: 1) merging is easier at lower population density;2) merging is easier if the direction of the merging crowd is same as the direction of the crowd in the staircase;and 3) merging is easier if the door is initially opened,and the evacuation speed is decreased by 30% when the door is initially closed.