4.1 This practice describes the procedures that can be used to prepare new and weathered zinc-coated surfaces on after-fabrication steel products for painting, and that can improve the bond of paint to the zinc surface.

1.1 This practice describes methods of preparing surfaces of new and weathered hot-dip galvanized steel for painting with liquid paint and coating products. Preparing surfaces of new and partially weathered galvanized steel for powder coating is addressed in Practice D7803. Hot-dip galvanized steel is produced by the immersion of fabricated or unfabricated products in a bath of molten zinc, as specified in Specifications A123/A123M or A153/A153M. This practice covers surface preparation on iron and steel products and hardware that have not been painted previously. Galvanized surfaces may have been treated with protective coatings to prevent the occurrence of wet storage stain. This practice does not apply to sheet galvanized steel products nor to the coil coating or continuous roller coating processes. Sheet and coil surface preparation can be done in accordance with Practice D7396.

1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.