一起静电火灾事故的调查与视频分析

Investigation and Video Analysis of a Fire Caused by Static Electricity

在调查一起体育用品生产车间火灾过程中,通过对监控视频影像的分析与处理,对起火点和火灾初期火焰的特征进行了捕捉、分析,根据静电火灾发生机理,结合视频影像中火灾的蔓延过程及特征,分析认定了起火原因。通过该火灾的调查与分析得出:静电火灾的发生发展过程为静电产生,电荷积累,电弧放电,引燃周围可燃气体;静电火灾的初期呈现预混燃烧状态,蔓延速度可达7.86 m·s^-1,现场可燃气体分布决定着火势蔓延方向;调查时易造成起火点及蔓延方向分析的错误,因此需对现场监控视频进行逐帧分析,对火灾蔓延方向进行矢量分析,进而准确认定起火点和蔓延过程,辅助认定起火原因。

In the investigation of a sporting workshop fire,according to the mechanism of static electricity fire and fire propagating characteristics shown in the video image,the cause of the fire was identified.The fire spot and initial fire characteristic was captured by processing and analyzing the monitory video.This investigation shows that the occurrence and development of a static fire have several stage,including electrostatic generation,electrostatic accumulation,arc discharge and the ignition of surrounding combustible gas;the initial stage of the static electricity fire presents a premixed combustion state,the propagating speed can reach 7.86 m·s^-1,and the distribution of the combustible gas on site determines fire propagating direction;during the investigation,it is easy to make mistakes in the identification of fire spot and fire propagating direction.So in order to find the fire spot accurately and identify the cause of fire,it is necessary to analyze monitoring video frame by frame and conduct vector analysis of fire propagating direction.