ISO/PWI 8502-16

Preparation of steel substrates before application of paints and related products — Tests for the assessment of surface cleanliness — Part 16: Extraction of water soluble contaminants for analysis, the saturated filter paper method

Scope

This part of ISO 8502 describes a method of extracting, for analysis, water soluble contaminants from a surface by use of saturated filter paper which can be attached to any surface, regardless of its shape (flat or curved) and its orientation (facing in any direction, including downwards).

The method described is suitable for use in the field to determine the presence of water soluble contaminants before painting or a similar treatment.

NOTE The extraction method might give a false conductivity result or not take all the water-soluble material off the surface because of: (1) Soluble materials hiding in the crevices or under folds of metal; (2) Soluble materials under corrosion layers, passivation layers produced by corrosion inhibitors, oil, grease, or other non-visible thin films.