See more in depth article comparing ISO 1461 vs. A123.

If I galvanize to ASTM A123 or A153, will I meet the requirements of ISO 1461?

ISO 1461, Hot-dip galvanized coatings on fabricated iron and steel articles Specifications and test methods, is produced by the International Organization for Standardization (ISO) as an industry standard for galvanizing. The standard holds requirements for hot-dip galvanized steel comparable to those found in both ASTM A123, Standard Specification for Zinc (Hot-Dip Galvanized) Coatings on Iron and Steel Products, and ASTM A153, Standard Specification for Zinc Coating (Hot-Dip) on Iron and Steel Hardware. North American specifiers and galvanizers typically use ASTM A123 and A153 for steel products and fasteners to be hot-dip galvanized. However, ISO 1461 which standardizes the European galvanizing industry both large structural pieces and centrifuged hardware is also sometimes used in Canada, the United States, and Mexico.

If a customer wishes to use ISO 1461 on their project, galvanizers need to know what the requirements of the standard are and if they can meet them. As North American galvanizers, the question becomes, If I galvanize the steel to ASTM A123, will I meet the requirements of ISO 1461?

Hot-dip galvanizing to ASTM A123/A123M or ASTM A153/A153M will typically lead to an end quality equivalent to ISO 1461. However, there are significant differences between ISO 1461 and ASTM A123/A123M or A153/A153M regarding inspection methods and documentation. It is recommended to refer directly to ISO 1461 for the specific requirements regarding inspection methods and minimum average coating thickness requirements. The European General Galvanizers Association (EGGA) provides additional guidance on their website.

The information below on comparing these specifications is not intended to be used as an exhaustive guide on the inspection requirements or contractual obligations when substituting one specification for the other.

View ISO 1461 vs. A123 Guide

Regarding the minimum average thickness requirements, differences between the standards may be considered negligible and Galvanizers will most likely meet the requirements of ISO 1461 if they galvanized to A123. The table below helps point out these subtle differences. The table assumes steel is being galvanized according to the thicknesses in the left-hand column. This column uses the standard units of mm found in ISO 1461 but can be converted to imperial units. The table then gives the requirements of ISO 1461, and the thickness of steels whose A123 requirements overlap. Notice the ASTM requirements for coating thickness on wire never meet the ISO standards.

Despite the small differences between the standards, if steel is galvanized in accordance with ASTM A123 or A153, it will more than likely meet the requirements of ISO 1461.

	ISO 1461 Table 3 Mean Coating Thickness Minimum (μm)	ASTM A123 will meet requirements if:
Steel thicker than 6mm	85	Structural Shapes between 6.0 and 6.4 mm 75 Structural Shapes Thicker than or equal to 6.4 mm 100 Plate 6.0 to 16 mm 75 Plate thicker than 16 mm 100 Pipe and Tubing thicker than 6.0 mm 75
Steel thicker than 3mm and up to 6mm	70	Structural Shapes and Plate between 3.0 and 3.2 mm 65 Pipe and Tubing between 3.0 and 3.2 mm 45 Structural Shapes, Pipe and Tubing, and Plate between 3.2 and 6.0 mm 75
Steel thicker than 1.5mm and up to 3mm	55	Structural Shapes and Plate between 1.6 and 3.0 mm 65 Structural Shapes and Plate between 1.5 and 1.6 mm 45 Pipe and Tubing between 1.5 and 3.0 mm 45
Steel thinner than 1.5mm	45	Structural Shapes, Pipe and Tubing, and Plate thinner than 1.5 mm 45