ISO 8504-2:2019

Overview - ISO 8504-2:2019 (Abrasive blast‑cleaning)

ISO 8504‑2:2019 specifies abrasive blast‑cleaning methods used to prepare steel substrates before the application of paints and related protective coatings. The standard describes the effectiveness and fields of application of individual blast methods, the typical equipment and abrasives to use, and the recommended procedural stages (before, during and after blasting). It is primarily intended for hot‑rolled steel (to remove mill scale, rust and old coating) and can be applied to sufficiently thick cold‑rolled steel.

Key topics and technical requirements

• Abrasive types and properties: classification of metallic and non‑metallic abrasives (shot, grit, cylindrical), importance of particle shape, hardness and size.
• Abrasive condition requirements: abrasives must be dry (unless used in wet systems), free‑flowing and free from corrosive or adhesion‑impairing contaminants; permanently contaminated abrasives are not permitted.
• Blast‑cleaning methods: coverage of dry methods (centrifugal, compressed‑air, vacuum/suction‑head) and wet methods (moisture‑injection, compressed‑air wet, slurry, pressurized‑liquid).
• Equipment and operation: guidance on mobile vs stationary equipment, metering abrasives into the blast stream, and how blasting parameters influence surface profile and cleanliness.
• Procedure and quality control: preparatory steps, blasting execution, post‑blast handling and assessment of blast‑cleaned surfaces.
• Surface profile and assessment: emphasizes the resultant secondary profile and refers to ISO 8503 series methods for measuring surface roughness and profile comparators.
• Health, safety and environmental considerations: requirements and considerations for safe use and management of abrasives and spent material (as referenced in normative documents).

Practical applications

ISO 8504‑2 is used to ensure reliable surface preparation where coating performance depends on substrate cleanliness and profile. Typical applications include:

• Structural steelwork (bridges, buildings)
• Marine and offshore assets (ship hulls, platforms)
• Storage tanks, pressure vessels and pipelines
• Industrial maintenance and refurbishment projects
  Benefits include controlled removal of mill scale/rust, reproducible surface profiles for adhesion, high production rates, and adaptability for in‑place or shop operations.

Who should use this standard

• Coating specifiers and system designers
• Surface preparation and blasting contractors
• Quality assurance/inspection personnel and corrosion engineers
• Asset owners and maintenance planners seeking consistent coating performance

Related standards

• ISO 8501 (visual assessment of surface cleanliness)
• ISO 8502 (tests for surface cleanliness)
• ISO 8503 (surface roughness/profile of blast‑cleaned steel)
• ISO 11124 / ISO 11126 (specifications for metallic and non‑metallic blast‑cleaning abrasives)

ISO 8504‑2:2019 provides the practical, method‑level guidance needed to select appropriate abrasive blast‑cleaning processes and achieve consistent, verifiable steel surface preparation prior to coating.