ISO 9223 Steel Corrosion Rate (2020–2024)

Overview

This dataset represents the modeled first-year atmospheric corrosion rate of carbon steel based on the ISO 9223 atmospheric corrosivity framework.

Corrosion rates were calculated using five-year climatological averages (2020–2024) of:

• Temperature
• Relative Humidity
• Sulfate Deposition
• Chloride Deposition

The resulting raster provides:

• First-year steel corrosion rate estimates
• ISO 9223 corrosivity classifications
• Continuous atmospheric corrosion exposure mapping

at approximately 1 km spatial resolution.

Units:

• Micrometers per year (µm/year)

Background

ISO 9223 provides internationally recognized dose-response functions for estimating atmospheric corrosion rates of engineering materials using climatic and pollutant exposure variables.

This dataset applies the ISO 9223 carbon steel dose-response function to generate global corrosion rate predictions using gridded environmental datasets representing average conditions during the period 2020–2024.

These classifications are widely used for:

• Protective coating selection
• Structural durability assessments
• Corrosion engineering
• Atmospheric exposure analysis
• Asset integrity management

ISO 9223 Steel Dose-Response Function

The carbon steel corrosion model is:

math r_{corr} = 1.77 \cdot P_D^{0.52} \cdot e^{(0.020RH + f_{St})} + 0.102 \cdot S_D^{0.62} \cdot e^{(0.033RH + 0.040T)}

where:

math f_{St} = 0.150(T - 10) \quad \text{if } T \leq 10^\circ C

math f_{St} = -0.054(T - 10) \quad \text{if } T > 10^\circ C

Variable Definitions

The reader is referred to the official ISO 9223 standard for additional material-specific equations and atmospheric corrosivity methodologies.

ISO 9223 Corrosivity Categories (Steel)

Engineering Interpretation Classes

For visualization and continuous raster interpretation, the following intermediate classes are provided:

These intermediate classes are not part of the ISO 9223 standard and are provided solely for GIS visualization and continuous corrosion exposure interpretation.

Interpretation Notes

Lower corrosion rates are typically associated with:

• Arid climates
• Inland environments
• Low humidity regions
• Low pollutant exposure
• Cold dry climates

Higher corrosion rates are typically associated with:

• Marine environments
• Coastal exposure
• Humid tropical climates
• Elevated chloride deposition
• Elevated sulfate deposition
• Persistent moisture exposure

Carbon steel corrosion behavior is particularly sensitive to atmospheric moisture, chloride deposition, sulfur-containing pollutants, and long-term wet-dry cycling.

Spatial Resolution

Data Sources

Primary environmental inputs include:

• NOAA Integrated Surface Database (ISD)
• Government of Canada Climate Archive
• NASA MERRA-2 Reanalysis
• National Data Buoy Center (NDBC)
• EPA National Atmospheric Deposition Program (NADP)

Derived raster inputs include:

• Mean Annual Temperature
• Mean Relative Humidity
• Mean Chloride Deposition
• Mean Sulfate Deposition
• Time of Wetness (TOW)

Intended Applications

This dataset may be used for:

• Atmospheric corrosion assessment
• Protective coating selection
• Structural durability analysis
• Asset integrity management
• Corrosion engineering
• Environmental exposure analysis
• GIS visualization

Related Datasets

Primary Corrosion Layers

• ISO 9223 Steel Corrosion Rate
• ISO 9223 Zinc Corrosion Rate
• ISO 9223 Aluminum Corrosion Rate
• ISO 9223 Copper Corrosion Rate

Primary LE (Local Emissions) Corrosion Layers

• ISO 9223 Steel LE V4
• ISO 9223 Zinc LE V4
• ISO 9223 Aluminum LE V4
• ISO 9223 Copper LE V4

Supporting Environmental Layers

• Mean Chloride Deposition
• Mean Sulfate Deposition
• Mean Annual Temperature
• Mean Relative Humidity
• Time of Wetness (TOW)

Supporting Coastal & Terrain Layers

• Distance to the Nearest Coast
• Bathymetry 2024 – Terrain Elevation
• WindRIX Terrain–Wind Exposure Index
• Wind Resultant Direction (0–360°)
• Wind Speed

Attribution

Joseph Mazzella
AtmosphericIQ LLC
Engineering Director, Inc.

Dataset Citation

Mazzella, J., Hayden, T.,(2026). ISO 9223 Steel Corrosion Rate Raster (2020–2024). AtmosphericIQ LLC / Engineering Director, Inc.

Standards Citations

ISO 9223:2012. Corrosion of metals and alloys — Corrosivity of atmospheres — Classification, determination and estimation. International Organization for Standardization (ISO).
https://www.iso.org/standard/53499.html

ISO 12944-2. Paints and varnishes — Corrosion protection of steel structures by protective paint systems — Part 2: Classification of environments. International Organization for Standardization (ISO).
https://www.iso.org/standard/64834.html

Supporting Dataset Citations

NASA Global Modeling and Assimilation Office (GMAO). MERRA-2 Atmospheric Reanalysis Dataset.
https://gmao.gsfc.nasa.gov/reanalysis/MERRA-2/

NOAA National Centers for Environmental Information (NCEI). Integrated Surface Database (ISD).
https://www.ncei.noaa.gov/products/land-based-station/integrated-surface-database

Version Information