What is the difference between Class A and Class B foam?
Class A foam is for Class A materials which is wood, paper, brush, all common combustables. Class B foam is for petro chemical fires, gasoline, oil, crude, jet fuel, etc. There are many TYPES of Class B foams and the user must be carefull to use the correct Class B foam for the petrochemical that is involved. There is a detailed discussion of Class A foam in the TFT library under Maintenance Information.