The is an indispensable tool for any coating inspector, contractor, or engineer. Understanding the difference between Class 1, 2, and 3—and correctly applying the pressure-sensitive tape method—can mean the difference between a 20-year coating lifespan and a 6-month failure.
Ensuring the longevity of protective coatings on steel structures starts with surface preparation. Before paint or specialized coatings are applied, the surface must be free from contaminants, particularly dust, which can act as a barrier to adhesion, leading to premature coating failure.
Illuminated Magnifier : For evaluating fine particle size classes. iso 85023 dust level chart pdf updated
The standard provides two main evaluation scales from 0 to 5. Rating/Class Dust Quantity Assessment Dust Particle Size Description No dust visible on tape No particles visible under 10x magnification 1 Lowest dust quantity
ISO 8502-3 Dust Level Chart is a standard visual tool used in the protective coatings industry to evaluate surface cleanliness after blast cleaning. The most current official version of the standard is ISO 8502-3:2017 , which replaced the original 1992 version. Электронный магазин стандартов Core Functionality The is an indispensable tool for any coating
Particles clearly visible with the naked eye (between 50 μm and 100 μm).
Provides expert, compliant testing devices and educational materials on the 8502-3 standard. Before paint or specialized coatings are applied, the
As of this writing, the most current and active version of the standard remains . This edition was a technical revision that replaced the original ISO 8502-3:1992.
For field inspectors, quality control managers, and blasting contractors, having a high-resolution, updated reference chart is essential for accurate assessments.
The standard also requires inspectors to categorize the size of the predominant dust particles: Particles not visible under 10x magnification.
For highly critical environments or confined spaces (like tank interiors), continuous industrial vacuuming yields far better results than air blowing, which often just redistributes dust.