ISO 18724:2025

Specifies a spectrometric method for determination of chromium(VI) in water. The method is applicable to the determination of dissolved chromium(VI) in waters in the concentration range of 0,05 mg/l to 3 mg/l. The application range may be extended by dilution of the sample.

ISO 18412:2005 specifies a method for the determination of chromium(VI) in drinking water in mass concentrations between 2 micrograms per litre and 50 micrograms per litre. For the determination of higher concentrations, the sample is diluted prior to analysis. The method may also be applied to weakly polluted ground and surface water, provided the matrix does not contain interfering reducing agents. This method was not used for estuarine water and seawater, so the user is responsible for the validation of the method for these matrices.

ISO 23913:2006 specifies flow injection analysis (FIA) and continuous flow analysis (CFA) methods for the determination of chromium(VI) in various types of water. The method applies to the following mass concentration ranges: for FIA (20 to 200 micrograms per litre and 200 to 2 000 micrograms per litre for surface water, leachates and waste water) and for CFA (2 to 20 micrograms per litre and 20 to 200 micrograms per litre for drinking water, ground water, surface water, leachates and waste water). The range of application may be changed by varying the operating conditions. Seawater may be analysed by these methods with changes in sensitivity and after adaptation of the reagent and calibration solutions to the salinity of the samples.