Résumé
The method is applicable to products yielding a quantity of sulphated ash equal to or less than 0.5 % (m/m). The principle is based on combustion of a test portion and calcination of the residue in the presence of sulphuric acid in a platinum or porcelain dish between 800 °C and 850 °C. Weighing of the residue thus obtained. - Replaces ISO Recommendation R 1616-1970.