This part of IS0 6703 specifies three methods for the determination of easily liberatable cyanide (see clause 2) in water. The methods are applicable to water containing less than 50 mg of easily liberatable cyanide (as cyanide ions) per litre, and less than 100 mg of total cyanide (as cyanide ions) per litre, but higher concentrations may be determined by suitable dilution of the sample.