Determination of certain substances in electrotechnical products - Part 7-2: Hexavalent chromium - Determination of hexavalent chromium (Cr(VI)) in polymers and electronics by the colorimetric method
NORMA vydána dne 28.3.2017
Designation standards: IEC 62321-7-2-ed.1.0
Publication date standards: 28.3.2017
The number of pages: 35
Approximate weight : 105 g (0.23 lbs)
Country: International technical standard
Kategorie: Technické normy IEC
IEC 62321-7-2:2017 describes procedures to measure hexavalent chromium, Cr(VI), quantitatively in samples of polymers and electronics. This method employs organic solvent to dissolve or swell the sample matrix, followed by an alkaline digestion procedure to extract Cr(VI) from samples. Studies have shown that organic;alkaline solution is more effective than acidic solution in extracting Cr(VI) from soluble and insoluble samples. Minimal reduction of Cr(VI) to Cr(III) or oxidation of Cr(III) to Cr(VI) occurs under alkaline conditions. The first edition of IEC 62321:2008 was a stand-alone standard that included an introduction, an overview of test methods, a mechanical sample preparation as well as various test method clauses. This first edition of IEC 62321-7-2 is a partial replacement of IEC 62321:2008, forming a structural revision and generally replacing Annex C. IEC 62321-7-2 is the final replacement part of the corresponding clauses in IEC 62321:2008. It has the status of a horizontal standard in accordance with IEC Guide 108 . lIEC 62321-7-2:2017 decrit des procedures de mesure quantitative du chrome hexavalent, Cr(VI), dans des echantillons de polymeres et de produits electroniques. Cette methode emploie un solvant organique destine a dissoudre ou a faire gonfler la matrice de lechantillon, puis une procedure de digestion alcaline visant a extraire le chrome hexavalent des echantillons. Des etudes ont demontre que la solution alcaline/organique est plus efficace que la solution acide pour extraire le Cr(VI) dechantillons solubles et insolubles. La reduction minimale du Cr(VI) en Cr(III) ou loxydation du Cr(III) en Cr(VI) se produit en milieu alcalin. La premiere edition de lIEC 62321:2008 etait une norme "autonome" qui comprenait une introduction, une vue densemble des methodes dessai, la preparation mecanique dechantillon, ainsi que differents articles relatifs a des methodes dessai. Cette premiere edition de lIEC 62321-7-2 remplace en partie lIEC 62321:2008, constituant une revision structurelle et remplacant, en general, lAnnexe C. LIEC 62321-7-2 remplace definitivement les articles correspondants dans lIEC 62321:2008. Elle a le statut de norme horizontale conformement au Guide IEC 108.