TECHNICAL STANDARD
ISO 8504-2
Preparation of steel substrates before application of paints and related products — Surface preparation methods — Part 2: Abrasive blast-cleaning
ISO
Edition 3 / 2019
Current
WHAT DOES THIS STANDARD COVER?
Covers abrasive blast-cleaning methods used to prepare steel surfaces before application of paints and related products.
WHY IS IT RELEVANT?
Relevant to inspection of abrasive blast-cleaning operations, including understanding the preparation method and its field of application.
KEY INSPECTION CONSIDERATIONS
ISO 8504-2 addresses abrasive blast-cleaning methods used to prepare steel surfaces before application of paints and related products. Abrasive blast cleaning can remove rust, mill scale, existing coating and other material while also producing or modifying the surface profile. The resulting surface condition is influenced by factors including the original steel condition, abrasive characteristics, blast-cleaning equipment and the execution of the preparation process. The preparation process should therefore be controlled together with inspection of the resulting visual cleanliness, surface profile and other specified surface characteristics.
WHAT THE STANDARD SHOULD NOT BE USED TO ASSUME
Use of abrasive blast cleaning does not automatically mean that a specified preparation grade such as Sa 2½ has been achieved. The resulting surface must be visually assessed against the applicable preparation requirement. Abrasive blast cleaning also does not automatically demonstrate compliance with soluble-salt, dust or surface-profile requirements. These characteristics require separate inspection where specified. The abrasive itself can also influence the prepared surface and should meet applicable project requirements.
PRACTICAL INSPECTION APPLICATION
ISO 8504-2 is relevant when reviewing and inspecting abrasive blast-cleaning operations on steel structures. Inspection may include consideration of the abrasive, blast-cleaning equipment and process together with assessment of the resulting steel surface. Visual preparation grade, surface profile, dust, soluble contamination and environmental conditions should be inspected using the applicable project requirements and test methods. Any areas that do not meet the required final condition should be identified for further preparation before coating.
RELATED TECHNICAL STANDARDS
RELATED TECHNICAL TOPICS
abrasive blast-cleaning; surface preparation; blast profile
RELATED PIL GUIDANCE
Practical guidance on assessing abrasive blast-cleaned steel surface profile before protective coating application.
RELATED EXPERTISE
Coating Inspection; Technical Consultancy
ABOUT THIS TECHNICAL SUMMARY
Paint Inspection Ltd provides this information to help inspectors, engineers, asset owners and contractors understand the practical relevance of commonly referenced protective coatings standards. This page is PIL technical guidance and does not reproduce or replace the published standard. Users should refer to the current published standard, project specification, coating manufacturer requirements and other applicable contract documents when establishing project requirements or acceptance criteria.
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OFFICIAL STANDARD
PIL technical summaries are intended to explain the inspection relevance of industry standards and do not replace the published document.
STATUS AND SOURCE VERIFICATION
ISO 8504-2:2019 remains the published International Standard. A replacement edition is under development; edition and status were checked against the official ISO catalogue in September 2026.