ISO International Standard

ISO 18852:2015 specifies a method for the determination of the nitrogen surface area (NSA) of carbon blacks and other rubber compounding ingredients, like silicas and zinc oxides, based on the Brunauer, Emmett and Teller (BET) theory of gas adsorption using a multipoint determination as well as the determination of the statistical thickness surface area (STSA), otherwise known as the external surface area. STSA, however, is not applicable to silica and zinc oxide.

The method can also be used for verifying “single-point” procedures described in ISO 4652 and other standards.