Method for the calibration and / or adjustment of an analysis device for chemical substances in fluids, particularly in aqueous solutions

The invention relates to a method for calibrating and / or adjusting an analysis device for chemical substances in fluids, particularly in aqueous solutions, wherein a predetermined concentration of a chemical substance is measured in a reference liquid by the reference liquid is added to produce a color change with a reagent and is then irradiated with light of a predetermined wavelength, wherein a concentration is determined by the absorption of light by the reference fluid, which is compared with the predetermined concentration of the reference liquid. In a method for calibration and / or adjustment of an analysis device for liquids, in which a, in the measurement process embedded calibration and / or adjustment without a long interruption of the measurement process is possible, the predetermined concentration of the reference liquid is produced by mixing at least two standard solutions (11, 14) obtained containing different concentrations of the chemical substance.