Abstract:  The investigation of Xiangshui's 3·21 particularly serious explosion was recorded. The explosion location identification process, technology methods for explosion time identification, explosion materials identification process, explosion cause analysis and identification process were introduced. The usage of investigation technology method, experiments methods, on site reconstruction technology and map locating technology were summarized. Comprehensive suggestions to the investigation of scenario large-scale chemical fire and explosion were offered.

Key words:  fire and explosion accident, fire investigation, explosion material