This International Standard specifies a method for the photometric determination of the total cyanide and easily-liberatable cyanide content in soil using automated distillation-continuous flow analysis. The International Standard applies to all types of soil with cyanide contents above 1 mg/kg on the basis of dry matter, expressed as cyanide ion. NOTE Sulfide concentrations in the sample higher than 40 mg/kg dry matter cause interference. This effect can be recognized by the split peaks and as a slow decrease of the detector signal and can only be prevented by diluting the sample extract.