This International Standard specifies methods for determining the loss on heating of carbon black for use in the rubber industry. This loss on heating is due primarily to loss of moisture, but traces of other volatile materials may also be lost. These methods are not applicable to treated carbon blacks which contain added volatile materials. One of the following three methods is used: — method 1: gravity-convection oven method; — method 2: moisture balance method; — method 3: infrared irradiation method (rapid method). Note that method 1 is considered as the reference method. Apparatus equivalent to that specified may be used provided the same results are obtained.