DIN EN ISO 12944-4:2018-04

Professional preparation of steel surfaces for durable corrosion protection systems

The DIN EN ISO 12944-4 specifies requirements for the types of surfaces and their preparation before the application of protective paint systems. It helps planners, coating contractors and operators of steel structures select suitable surface preparation methods and ensure durable, effective protective coatings. The standard is part of the DIN EN ISO 12944 series on the corrosion protection of steel structures by protective paint systems.

What does DIN EN ISO 12944-4 cover?

The standard describes the types of surfaces to be prepared and surface preparation methods for steel structures. It focuses on uncoated steel surfaces, metal-coated surfaces, prefabrication primers and previously coated surfaces, as well as their proper preparation before coating. The standard also defines requirements for cleaning methods, blast-cleaning, surface preparation grades, roughness and the assessment of prepared surfaces.

New provisions have been added for the chemical treatment of surfaces, which can be used particularly on galvanized surfaces to improve the adhesion of coating systems.

Topics covered

• Types of surfaces on steel structures before coating
• Preparation of uncoated, galvanized and coated surfaces
• Mechanical, chemical and water-based cleaning methods
• Blast-cleaning, sweep blasting and spot blasting
• Surface preparation grades in accordance with ISO 8501
• Roughness and surface profile of prepared steel surfaces
• Assessment of prepared surfaces before coating
• Temporary corrosion protection before coating
• Environmental, health and occupational safety aspects

Practical relevance

The quality of surface preparation has a decisive influence on the adhesion, durability and performance of coating systems. DIN EN ISO 12944-4 provides a consistent basis and helps companies define suitable preparation methods and preparation grades. This can reduce corrosion damage and significantly extend the service life of steel structures.

The requirements for blast-cleaning methods, surface preparation grades, roughness and the assessment of prepared surfaces are particularly relevant, as these factors have a major influence on the effectiveness of the entire corrosion protection system.

Changes compared with DIN EN ISO 12944-4:1998-07

The 2018 edition was technically revised. The most important changes include:

• Addition of the new definition “chemical treatment”
• New section on chemically treated surfaces
• New subsection, “Chemical treatment”, within the surface preparation methods
• Revision of the requirements for uncoated surfaces and the assessment of prepared surfaces
• Revision of the provisions for preparing temporarily or partially protected surfaces
• Updated normative references and extensive editorial revision

Target audience

• Corrosion protection planners
• Coating contractors
• Steel construction companies
• Inspectors and experts
• Operators of steel structures
• Quality managers
• Manufacturers of coating systems
• Professionals in surface preparation and corrosion protection

Conclusion

The DIN EN ISO 12944-4 provides the basis for the proper preparation of steel surfaces before coating. With its requirements for surface types, preparation methods and preparation grades, it supports the standards-compliant execution of corrosion protection measures and makes a significant contribution to the durability of coated steel structures.

This document replaces DIN EN ISO 12944-4:1998-07 .