Proper surface preparation is critical for coating adhesion; failure to meet specified dust limits directly undermines the entire coating system's longevity and performance.
Surface contamination is the primary cause of premature coating failures. Even after blast-cleaning steel to a pristine finish, invisible or tiny particulate matter can settle back onto the substrate. If ignored, this dust forms a barrier that disrupts coating adhesion, traps moisture, and accelerates osmotic blistering and under-film corrosion.
The new chart emphasizes that even if quantity is Class 2, if any particle exceeds 100 µm, the overall rating drops to Class 3.
The procedure for using the chart is standardized to ensure reliable results: iso 85023 dust level chart pdf updated
An official, updated ISO 8502-3 chart evaluates dust using two primary metrics: and Particle Size Class . 1. Dust Quantity Rating (0 to 5)
When she peels back the tape and places it on a contrast-colored assessment plate, Sarah compares her sample against the defined in the updated ISO 8502-3:2017 standard. INTERNATIONAL STANDARD ISO 8502-3
The complete, authoritative standard can be purchased via ISO or ANSI. Proper surface preparation is critical for coating adhesion;
Master Guide to the ISO 8502-3 Dust Level Chart: The Ultimate Cleanliness Resource for Protective Coatings
While official ISO standards must be purchased directly from ISO or national bodies, updated PDF summary charts allow field inspectors to quickly reference specifications on tablets and smartphones without carrying bulky paper manuals into confined spaces.
: Press a 200 mm length of tape onto the prepared steel. Apply firm, consistent pressure (typically with a thumb or a calibrated spring-loaded roller Removal & Mounting : Peel the tape and place it on a contrasting display board or assessment plate. Comparison If ignored, this dust forms a barrier that
If you can tell me you are in (shipbuilding, infrastructure, oil & gas), I can provide more specialized, industry-focused inspection guidance . YouTube·The Institute for Oil & Gas Sector (IOGS)
The ISO 8502-3 dust level chart is a widely used reference guide for assessing the dust level on steel surfaces. The chart categorizes dust levels into four classes, ranging from A (clean) to D (very dirty). The chart considers the density and size of dust particles, as well as the surface roughness of the steel.
