This method is used for the determination of chloride in aqueous samples and extracts. The EPA range of this method is 1-200 mg/L. However, this method is also applicable to other ranges.


Thiocyanate is displaced from mercuric thiocyanate by the chloride ion. The liberated thiocyanate reacts with ferric ion to form the colored complex [Fe(SCN)] +2 . The amount of complex formed is directly proportional to the concentration of chloride ion present in the sample. The colored complex is measured at 480 nm. (2)


There are no significant interferences. Filter turbid samples before determination.

System Method # Range(s)
Flow System A090 1-200 mg/l
Astoria 2 A090 1-200 mg/l
rAPID-T D090 1-50 mg/l