Overview
EN ISO 12944-2:2017 - "Paints and varnishes - Corrosion protection of steel structures by protective paint systems - Part 2: Classification of environments" defines how to classify the environments that expose steel structures to corrosion. The standard describes atmospheric-corrosivity categories (based on mass or thickness loss of standard specimens), categories for structures immersed in water or buried in soil, and identifies special corrosion stresses that can significantly increase corrosion rates. The environmental classification provided is a primary input to selecting appropriate protective paint systems and determining required performance levels.
Key topics
- Atmospheric-corrosivity categories: Classification of atmospheric environments by corrosivity using mass loss or thickness loss of standard specimens, with guidance on estimating local corrosivity (e.g., urban, marine, industrial conditions).
- Water and soil categories: Defined categories for structures immersed in water and buried in soil, addressing different corrosion mechanisms and environmental exposures.
- Special cases and corrosion stresses: Identification of factors (local contaminants, splash zones, tidal action, stray currents, biological factors) that can elevate corrosion rates and increase demands on coatings.
- Terminology and scope: Clear definitions (corrosivity, atmosphere, local environment) to ensure consistent application across projects.
- Role in paint system selection: The corrosivity category is specified as an essential parameter governing the choice of protective paint systems and related design/maintenance decisions.
Applications
EN ISO 12944-2:2017 is used to:
- Classify exposure environments for new and existing steel structures (bridges, buildings, offshore platforms, pipelines, tanks).
- Provide input for specifying protective paint systems, maintenance intervals and life-cycle planning.
- Support risk assessment and corrosion management programs in infrastructure, marine, industrial and civil engineering projects.
- Guide inspection criteria and lab testing requirements by correlating field exposure to standardized corrosivity categories.
Typical users:
- Asset owners and infrastructure operators
- Structural engineers and design consultants
- Coating specifiers and paint system manufacturers
- Contractors, applicators and quality inspectors
- Maintenance planners and corrosion engineers
Related standards
EN ISO 12944-2:2017 is part of the ISO 12944 series on protective paint systems. Key related parts include:
- ISO 12944-1 (General introduction)
- ISO 12944-3 to -9 (Design, surface preparation, paint systems, test methods, execution, specifications, offshore)
Use EN ISO 12944-2:2017 together with these parts to create complete, standardized specifications for corrosion protection of steel structures.
Keywords: EN ISO 12944-2:2017, ISO 12944-2, corrosion protection, atmospheric-corrosivity categories, protective paint systems, steel structures, classification of environments.
