DIN Standards Committee Petroleum and Natural Gas Industries
DIN EN ISO 4628-7
Paints and varnishes - Evaluation of degradation of coatings - Designation of quantity and size of defects, and of intensity of uniform changes in appearance - Part 7: Assessment of degree of chalking by velvet method (ISO 4628-7:2016); German version EN ISO 4628-7:2016
Beschichtungsstoffe - Beurteilung von Beschichtungsschäden - Bewertung der Menge und Größe von Schäden und der Intensität von gleichmäßigen Veränderungen im Aussehen - Teil 7: Bewertung des Kreidungsgrades nach dem Samtverfahren (ISO 4628-7:2016); Deutsche Fassung EN ISO 4628-7:2016
Overview
This part of ISO 4628 specifies a method suitable, in particular, for rating the degree of chalking on white or coloured exterior coatings and coating systems on rough surfaces (that is, those having a roughness greater than segment 4 of the reference comparator G as described in ISO 8503-1). The test method specified can also be used for the assessment of the degree of chalking of coatings and coating systems on smooth surfaces, but the method specified in ISO 4628-6:2011 is preferable for this purpose. The test method is applicable to coatings and coating systems on mineral substrates, for example fibre cement, brick, concrete, and renderings, independent of the structure of the surface. The method can be used quite effectively by experienced operators and is recommended for laboratory use as well as for onsite evaluation. When a reference to this test method is included in specifications, the test conditions (that is, weathering method and substrate) have to be agreed between the interested parties. The method described in this part of ISO 4628 is a relative ranking method and is therefore not suitable for use in agreements between parties. See, however, the Note to Table 1. Refer to ISO 4628-1 for the designation system for quantity and size of defects and the intensity of changes in appearance of coatings, as well as general principles of the system. The committee responsible for this standard is NA 002-00-07 AA "Allgemeine Prüfverfahren für Beschichtungsstoffe und Beschichtungen" ("General test methods for coating materials and coatings") of the Standards Committee Coatings and Coating Materials (NAB) at DIN.
Document: references other documents
Document: referenced in other documents
Responsible national committee
NA 002-00-07 AA - General test methods for coating materials and coatings
Responsible european committee
CEN/TC 139 - Paints and varnishes
