IEC 62321-7-1:2015 describes a boiling water extraction procedure intended to provide a qualitative determination of the presence of hexavalent chromium (Cr(VI)) in colourless and coloured corrosion-protection coatings on metallic samples. In this procedure, when Cr(VI) in a sample is detected below the 0,10 g;cm2 LOQ (limit of quantification), the sample is considered to be negative for Cr(VI). Since Cr(VI) may not be uniformly distributed in the coating even within the same sample batch, a ;grey zone; between 0,10 g;cm2 and 0,13 g;cm2 has been established as ;inconclusive; to reduce inconsistent results due to unavoidable coating variations. In this case, additional testing may be necessary to confirm the presence of Cr(VI). When Cr(VI) is detected above 0,13 g;cm2, the sample is considered to be positive for the presence of Cr(VI) in the coating layer.
It has the status of a horizontal standard in accordance with IEC Guide 108.