ISO 12944 Paints and Varnishes - Protection of Steel Structures Against Corrosion by Protective Paint Systems

The “ISO 12944 Paints and varnishes - Protection of steel structures against corrosion by protective paint systems” standard, developed by the International Organization for Standardization (ISO), consists of the following subsections published under the same title:

• The standard “ISO 12944-1 Part 1: General introduction” defines the general scope of the ISO 12944 standard. It provides some basic terms and definitions and a general introduction to other parts of the ISO 12944 standard. It also includes a general description of health, safety and environmental protection and guidelines for using the ISO 12944 standard (all parts) for a specific project.
• The standard “ISO 12944-2 Part 2: Classification of environments” describes the classification of the main environments to which steel structures are exposed and the corrosiveness of these environments. This standard,
  • It defines atmospheric corrosivity categories based on mass loss (or thickness loss) by standard samples and gives advice on the estimation of corrosivity by describing typical natural atmospheric environments to which steel structures are exposed.
  • Explain the different media categories for structures submerged in water or buried in the ground.
  • It provides information on some specific corrosion stresses that may cause a significant increase in the corrosion rate or place higher demands on the performance of the protective paint system.

The corrosion stresses associated with a particular environment or corrosivity category represent one of the fundamental parameters governing the selection of protective paint systems.

This standard does not deal with the classification of environments consisting of special atmospheres (e.g. in and around chemical and metallurgical plants).

• The standard “ISO 12944-3 Part 3: Design considerations” addresses the basic criteria for the design of steel structures to be coated with protective paint systems to prevent premature corrosion and deterioration of the coating or structure. The standard shows how problems with the application, inspection and maintenance of paint systems can be prevented by giving examples of suitable and unsuitable designs. Design measures that facilitate the handling and transportation of steel structures are also considered.
• The standard “ISO 12944-4 Part 4: Surface types and surface preparation” covers the following types of surfaces and their preparation for steel structures made of carbon or low alloy steel:
  • Uncoated surfaces
  • Thermally sprayed surfaces with zinc, aluminium or their alloys
  • Hot dip galvanized surfaces
  • Zinc electroplated surfaces
  • Striped surfaces
  • Surfaces painted with prefabrication primer
  • Other painted surfaces

This standard defines a number of surface preparation classes but does not specify any requirements for the condition of the substrate prior to surface preparation. Highly polished surfaces and work-hardened surfaces are not within the scope of this document.

• The standard “ISO 12944-5 Part 5: Protective paint systems” describes the types of paints and paint systems commonly used for corrosion protection of steel structures. This standard also includes guidelines for the selection of available paint systems for different environments other than the corrosivity categories CX and Im12944 defined in the ISO 2-4 standard and for different degrees of surface preparation.
• The standard "ISO 12944-6 Part 6: Laboratory performance test methods" describes laboratory test methods and test conditions for the evaluation of paint systems for corrosion protection of carbon steel structures. The test results of this standard are not intended to be considered as definitive information for determining durability but as an aid to the selection of suitable paint systems. This standard covers protective paint systems designed for application to uncoated steel, hot dip galvanized steel in accordance with ISO 1461 and steel surfaces with thermal spray metallic coatings in accordance with ISO 2063-1 and ISO 2063-2. However, this standard does not apply to protective paint systems for electrocoated or painted steel. For the corrosion categories C12944 to C2 and Im2 to Im5 defined in ISO 1-3, the environments are considered.
• The standard “ISO 12944-7 Part 7: Execution and supervision of painting work” describes the requirements for the execution and supervision of painting work on steel structures in the workshop or in the field. However, this standard does not apply to
  • Preparation of surfaces to be painted (ISO 12944-4) and supervision of such work.
  • Application of metallic coatings.
  • Pretreatment methods such as phosphating and chromating, and paint application methods such as dipping, powder coating or coil coating.
• The standard “ISO 12944-8 Part 8: Development of specifications for new work and maintenance” describes the principles for the development of specifications for the corrosion protection of steel structures using protective paint systems. This standard is relevant for new work and maintenance in the workshop or on site and is also applicable for the corrosion protection of individual components. This standard covers the corrosion protection of steel structures exposed to different corrosion stresses in environments such as indoor, outdoor and water immersion or burial, as well as specific stresses resulting from, for example, moderate or high temperatures. The need for different durability ranges is taken into account. Steel surfaces that are hot dip galvanized, metal sprayed, zinc electroplated or striped and previously painted are also within the scope of this standard.

This standard covers reference areas for assessing the quality of corrosion protection work and the performance of protective paint systems used. This standard provides detailed flow charts for planning new work and maintenance that are taken into account when writing a specification. This standard can also be used as a guide to defining appropriate specifications when excessive corrosion stresses or high temperatures occur or when protective paint systems are used on non-ferrous metals or other surfaces such as concrete.

• The standard “ISO 12944-9 Part 9: Protective paint systems for offshore and associated structures and laboratory performance test methods” describes the performance requirements for protective paint systems for offshore and associated structures (i.e. those exposed to the marine atmosphere and those immersed in sea or brackish water). Such structures are exposed to corrosivity category CX (offshore) and immersion category Im12944 environments as defined in ISO 2-4. This standard describes paint systems for high durability according to ISO 12944-1. This standard is applicable to structures made of carbon steel and does not cover Cadmium/bismuth chromium and zinc/bismuth chromium surfaces. It does not apply to surfaces under insulation or concrete. This standard is applicable to paint systems designed for a service temperature range of minus 20 degrees to plus 80 degrees and the performance test is intended to verify the suitability of the paint systems for this temperature range.

Our organization, which has been trying to support businesses from every sector with its testing, measurement, analysis and evaluation studies carried out in a wide range for years, has a strong staff that closely follows the developments in the world in the field of science and technology and constantly improves itself. In this context, testing services in accordance with the "ISO 12944 Paints and varnishes - Protection of steel structures against corrosion with protective paint systems" standard are also provided to businesses.