根据灭火器适用的一般火灾类别对灭火器进行分类，并给出评级方法。包括A类、B类、C类、D类、E类和F类的测试。

Classifies extinguishers according to the general classes of fires for which they are suitable and gives a method of rating. Tests for Classes A, B, C, D, E and F are included.