DIN EN ISO 6271:2016-05

DIN EN ISO 6271 specifies a spectrophotometric method for estimating the colour of clear liquids in terms of platinum-cobalt units (Pt-Co units). The test applies the Gardner colour scale described in Annex A. It is applicable to clear liquids having a colour characteristic similar to those of the platinum-cobalt colour scale specified in Annex A. For products with colours more intense than the Pt-Co stock solution the method specified in ISO 4630 applies. The spectrophotometric method provides a more precise way of measuring Pt-Co colour than a visual sample comparison by human eyes. The term "Pt-Co colour" used here is preferred over the terms "Hazen colour" and "APHA colour". The committee responsible for this standard is NA 002-00-02 AA "Lackrohstoffe" ("Raw materials for paints and varnishes") at DIN Standards Committee Coatings and Coating Materials (NAB).