This International Standard specifies two methods for the determination of chloride by flow analysis. The two basic methods are covered in separate clauses as follows:
a) Clause 3: Determination of chloride by flow analysis and photometric detection.
b) Clause 4: Determination of chloride by flow analysis and potentiometric detection.
Both methods are applicable to the analysis of water and waste water (including leachates) containing chloride in the concentration range from 1 mg/l to 1 000 mg/l. On a case-by-case basis the range of the analysis can be changed.
After dilution, samples with a chloride concentration > 1 000 mg/l can also be analysed.
The method with potentiometric detection is also applicable to turbid and/or coloured samples.
NOTE From the ecological point of view, the potentiometric method is preferable because it avoids the use of toxic reagents. When the photometric method is applied, volatile and solid wastes containing mercury should be discarded in accordance with environmental regulations.