I would like to express my deepest sympathies and heartfelt condolences to all those affected by the large-scale urban fire that occurred in Saganoseki, Oita City, in November 2025. My sincere thoughts are with the victims and their families for their safety and a swift recovery.
A preliminary field survey report on the Saganoseki urban fire, conducted by the Earthquake Fire Specialist Committee of the Japan Association for Fire Science and Engineering (JAFSE) (Chaired by Professor Emeritus Akihiko Hokugo, Kobe University), has been published on the JAFSE website. As part of this investigation, we conducted drone surveys on December 15 and 16, capturing comprehensive aerial imagery and data that revealed upper-floor fire spread and damage to adjacent wildlands that were previously difficult to assess from ground level alone.
Our investigation highlighted key factors contributing to the fire's expansion, including firebrand spotting driven by strong winds—which caused fire to jump approximately 1.4 km to Tobishima Island as well as spread discretely across the urban area—and regional characteristics such as high building density in a wooden-framed district. Furthermore, the survey analyzed "firebreak" locations where fire spread was halted through a combination of fire-resistant structures, road widths, firefighting efforts, and wind direction. Following our previous survey in Wajima City after the 2024 Noto Peninsula Earthquake, this investigation further demonstrates the effectiveness of drone-based spatial surveys in large-scale fire management.
For more details on the survey and analysis, please visit the official JAFSE link below.
JAFSE Survey Report: https://jafse.smoosy.atlas.jp/ja/firenews20260108
