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 This document specifies a method for the photometric determination of dissolved chromium(VI) using manual, e.g., hand photometry, or automated static, e.g., discrete analyser system, or automated dynamic techniques, e.g., flow injection analysis (FIA), continuous flow analysis (CFA), or ion chromatography with post-column derivatization (IC-PCR). The choice of the analytical technique to be used and needs-based sample preparation (e.g., matrix elimination) enables the determination of chromium(VI) in concentrations ≥0,02 µg/l in raw water, drinking water, surface water, aqueous eluates, cooling water and treated wastewater, provided that the Matrix does not contain any reducing substances. Typical areas of application for the static techniques as well as FIA and CFA are samples with chromium(VI) concentrations ≥2 µg/l. When using cuvettes with large optical path lengths, e.g. >100 mm, the range of application can be extended to concentrations <2 µg/l chromium(VI) (Annex A; Annex B; Annex C, Clauses C.1 and C.2). When using coupled techniques (e.g. IC PCR), chromium(VI) concentrations ≥0,02 µg/l can be determined (Annex C, Clause C.3). In some waters with reducing ingredients, chromium(VI) losses can occur just a few hours after sampling. Therefore, the method was not validated for leachate from landfills and raw sewage.

This dcoument specifies a method for the determination of fluoro-, chloro-, bromo- and iodo-organic compounds (AOF, AOCl, AOBr, AOI). Due to the high solubility of AgF in water the scope of ISO 9562 is restricted to Cl-, Br- and I-organic compounds (AOX, calculated as chlorine) because of the applied argentometric detection. The PN follows the proven AOX ISO 9562 method: adsorption of organohalogen compounds on activated carbon, oxidative combustion at 1000 °C with following alterations: constant water feed during combustion (hydropyrolysis), absorption of combustion gases in water, halide specific detection using ionchromatography. The method is applicable for the determination of 2 µg/l AOF, expressed as F 10 µg/l AOCl, expressed as Cl 1 µg/l AOBr, expressed as Br 1 µg/l AOI, expressed as I. Samples for determination of AOF are treated differently than samples for the determination of AOCl, AOBr and AOI. - Samples for determination of AOF are not acidified. The adsorption takes place under unchanged pH conditions. Washing is also performed with a neutral washing solution. - Samples for the determination of AOCl, AOBr and AOI are adjusted to a pH value 2 with nitric acid, the adsorption and washing take place in a nitric acid environment.