Great East Japan Earthquake Disaster Waste and the Occurrence of Fires

The Great East Japan Earthquake, which occurred on 11 March, 2011, was the largest earthquake in recent Japanese history and resulted in the generation of large amounts of disaster waste. As a result, many ‘outdoor storage areas’ were established within disaster zones, and more than 40 fires occurred in these storage areas within the Tohoku region. One possible cause of these fires is thought to have been the heat generated by fermentation of microorganisms that can proliferate easily under such conditions, often causing spontaneous ignition. In the present study, we aimed to determine the trigger of such faint heat generation. In particular, we collected samples from outdoor storage areas where fires have occurred. Then, we conducted thermal analysis to obtain basic data and developed safety measures to help prevent fires. Our results reveal that the heat generated during fermentation of wood chips and rotten tatami most likely acted as a trigger of spontaneous ignition.