Standards for the preparation of steel substrates

The performance of protective coatings of paint and related products applied to steel is significantly affected by the state of the steel surface immediately prior to painting. The principal factors that are known to influence this performance are:

  • The presence of rust and mill scale
  • The presence of surface contaminants, including salts, dust, oils and greases
  • The surface profile.

International Standards ISO 8501, ISO 8502 and ISO 8503 have been prepared to provide methods of assessing these factors, while ISO 8504 provides guidance on the preparation methods that are available for cleaning steel substrates, indicating the capabilities of each in attaining specified levels of cleanliness.

These International Standards do not contain recommendations for the protective coating systems to be applied to the steel surface. Neither do they contain recommendations for the surface quality requirements for specific situations, even though surface quality can have a direct influence on the choice of protective coating to be applied and on its performance. Such recommendations are found in other documents such as national standards and codes of practice. It will be necessary for the users of these International Standards to ensure that the qualities specified are:

compatible and appropriate both for the environmental conditions to which the steel will be exposed and for the protective coating system to be used
within the capability of the cleaning procedure specified.
The four International Standards referred to above deal with the following aspects of preparation of steel substrates:

BS ISO 8501 Visual assessment of surface cleanliness
BS EN ISO 8502 Tests for the assessment of surface cleanliness
BS EN ISO 8503 Surface roughness characteristics of blast-cleaned steel substrates
BS EN ISO 8504 Surface preparation methods

Each of these International Standards is in turn divided into separate parts.

BS EN 10028-1:2007+A1:2009
Preparation of steel substrates before application of paints and related products. Visual assessment of surface cleanliness. Preparation grades of welds, edges and other areas with surface imperfections
 
BS EN ISO 8501-4:2006
Preparation of steel substrates before application of paints and related products. Visual assessment of surface cleanliness. Initial surface conditions, preparation grades and flash rust grades in connection with ....(more)
 
BS EN ISO 8502-6:2006
Preparation of steel substrates before application of paints and related products. Tests for the assessment of surface cleanliness. Extraction of soluble contaminants for analysis. The Bresle method
 
BS EN ISO 8502-11:2006
Preparation of steel substrates before application of paints and related products. Tests for the assessment of surface cleanliness. Field method for the turbidimetric determination of water-soluble sulfate
 

 Your basket
Your basket is empty