Experiments were conducted to investigate into vertical travel time of the front of buoyant plumes induced in open space and shafts by ignition of methanol fire sources. Two other existing full scale experiments available for this purpose were also analyzed. It is found that the time for the front of a buoyant plume to reach a given height is negatively proportioned to 1/3 to the heat release rate and that proportional to 4/3 to the height in open space or region near fire source in shafts, while the time is proportional to 2/3 and 2 to the height when roof shaft is open and closed, respectively. Results of the experiments in different scales were well scaled by heat release rate and scales. In vertical shaft, a boundary at which from fire plume behavior (Z/D) differs from open space is 5.0, 2.5 for with and without a roof, respectively. Based on the experiments the equations to predict vertical travel time of fire plume front were proposed.
