DIN EN ISO 10304-4:2024-07

This document specifies a method for the determination of the dissolved anions chlorate, chloride and chlorite in water with low contamination (for example, drinking water, raw water or swimming pool water). The diversity of the appropriate and suitable assemblies and the procedural steps depending on them permit a general description only. For further information on the analytical technique, see Bibliography. Through appropriate sample pretreatment (for example, dilution), the specified areas of application of the analysis method for chlorate, chloride, and chlorite can be achieved when using a conductivity detector (CD), UV detector (UV) or amperometric detector (AD). Compared to DIN EN ISO 10304-4:1999-07, the clauses "Normative references" and "Bibliography" have been updated; eluent formulations in 6.8 have been deleted; an equivalent calculation method has been included in Clause 8 (see EP definition in equation (2)); a note that chlorite and chlorate may form during drinking water disinfection with chlorine dioxide (paragraph 2) and helpful measures to minimize/eliminate this formation (paragraph 3) have been added to 9.1 and the information on the results has been expanded. This document has been prepared by Technical Committee ISO/TC 147 "Water quality" in collaboration with the Technical Committee CEN/TC 230 "Water analysis", the secretariat of which is held by DIN (Germany). The responsible German standardization committee is Working Group NA 119-01-03-01-12 AK "Ionenchromatographisches Verfahren" ("Ion-exchange chromatographic method") of Working Committee NA 119-01-03 AA "Wasseruntersuchung" ("Water examination") at DIN Standards Committee Water Practice (NAW).