This International Standard specifies procedures for the preparation of water and acid extracts of air-dried soils and soil-like materials. The sulfate content of these extracts is determined by a gravimetric method in which barium chloride is added to the water or acid extract and the precipitate of barium sulfate is dried and weighed. The sulfate content is then calculated from the mass of the material used in the analysis and the mass of barium sulfate precipitated. This International Standard is applicable to all types of air-dried soils, for example pretreated according to ISO 11464. This International Standard consists of seven sections: Section 1: General Section 2: Pretreatment of samples and determination of dry matter contents Section 3: Extraction of soil with water at a mass: volume ratio of 1 soil:5 water Section 4: Extraction of soil with water at a mass: volume ratio of .1 soil:2 water Section 5: Extraction of soil with dilute hydrochloric acid Section 6: Determination of sulfate in solution by a gravimetric method using barium chloride Section 7: Precision of method and test report