火灾指在时间或空间上失去控制的燃烧所造成的灾害。火灾大多数是一种社会现象,发生火灾的主要原因可归纳为三个方面。一是人为的不安全行为(含放火);二是物质的不安全状态;三是工艺技术的缺陷。而人为的不安全行为是最主要的因素。火灾依据物质燃烧特性,可划分为A、B、C、D、E五类。A类火灾:指固体物质火灾。这种物质往往具有有机物质性质,一般在燃烧时产生灼热的余烬。如木材、煤、棉、 Fire refers to the disaster caused by the loss of control over time or space. Most of the fire is a social phenomenon, the main reason for the fire can be summarized into three aspects. First, the artificial unsafe behavior (including arson); the second is the material unsafe condition; third is the flaw in technology. Artificial insecurity is the most important factor. Fire according to the material combustion characteristics, can be divided into A, B, C, D, E five categories. A class of fire: refers to the solid material fire. Such substances tend to be organic in nature and typically produce burning embers on combustion. Such as wood, coal, cotton,