Workplace air — Determination of hexavalent chromium in airborne particulate matter — Method by ion chromatography and spectrophotometric measurement using diphenyl carbazide
ISO 16740:2005 specifies a method for the determination of the time-weighted average mass concentration of hexavalent chromium in workplace air. Separate sample preparation methods are specified for the extraction of soluble and insoluble hexavalent chromium. The method for insoluble hexavalent chromium can also be used to prepare samples for determination of total hexavalent chromium, if desired. ISO 16740:2005 is applicable to the personal sampling of the inhalable fraction of airborne particles, as defined in ISO 7708, and to static (area) sampling. The analytical method is applicable to the determination of masses of 0,01 micrograms to 10 micrograms of hexavalent chromium per sample, without dilution. The concentration range of hexavalent chromium in air for which the measuring procedure is applicable is determined by the sampling method selected by the user. For a 1 cubic metre air sample, without sample dilution, the working range is approximately 0,01 micrograms per cubic metre to 10 micrograms per cubic metre.