This International Standard specifies the Karl Fischer direct electrometric method for the determination of the water content of liquefied anhydrous ammonia for industrial use. The method is applicable to products having water contents equal to or greater than 50 mg/kg. NOTE — For water contents greater than 1 000 mg/kg, it is preferable to dilute the evaporation residue with anhydrous methanol in accordance with ISO 4276 and titrate an aliquot portion of the diluted solution.