OSHA Method W4001: HEXAVALENT CHROMIUM
Description
Wipe samples are collected by using firm hand pressure to move a 37-mm diameter polyvinyl chloride (PVC) filter, 5-µm pore size, across the surface of interest. An alternate medium for rough surfaces is a 37-mm binderless quartz fiber filter. Samples are digested with multiple buffered solutions. After dilution, an aliquot of this solution is analyzed for hexavalent chromium (Cr(VI)) by ion chromatography with postcolumn derivatization of the Cr(VI) with 1,5-diphenyl carbazide and detected by a UV-vis detector at 540 nm.
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