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.