Dimethyl ether (DME) has been focused as a substitute for diesel fuel, and a number of studies have investigated engines fueled with DME because DME has a low auto-ignition temperature and does not generate particulate matter (PM). Therefore, in the last few years, the construction of DME filling stations for trucks in Japan has been planned. The introduction of DME vehicles requires expansion of DME supply stations, which in turn requires the collection of safety data and the establishment of safety regulations. The present paper describes an experimental investigation of the hypothetical scenario in which liquid DME is accidentally released and an explosion occurs. In the present study, large-scale leakage and ignition of DME were investigated and flame propagation data was obtained. We also measured the overpressure of the blast wave and the heat flux from the fireball. When the ignition position is near the nozzle, the flame propagation velocity is higher. The overpressure from the DME fireball is stronger than that from DME/air mixture deflagration. In summary, these results provide safety data for safety management of DME filling stations. (C) 2012 Elsevier Ltd. All rights reserved.