This standard specifies methods for the determination of soluble sulfates, chlorides and nitrates in water for pigment samples, equivalent to ISO 787/13-1973 standards. Determination of dissolved ionic composition in water by using analytically pure reagents such as muriatic acid, silver nitrate (AgNO3), ammonium chloride, etc. If the method is suitable for a specific pigment, it must be indicated in the product standard and adjusted as necessary; if not, a special method needs to be developed. This standard provides uniform test specifications to ensure the accuracy and Reliability of results.