For asset owners and specifiers, the inclusion of ISO 8502-3 in project specifications—with clearly defined acceptance limits—is essential for ensuring that the significant investment in abrasive blasting yields a substrate truly ready for coating application. By quantifying dust, the industry moves closer to the goal of zero defects and extended asset lifecycles.
Dust rating = Q2 / S3 (Quantity = 2, Size = 3) dust test iso 8502-3
| Class | Description | Appearance | |-------|-------------|-------------| | 0 | No visible dust | Particles not visible under magnification | | 1 | Very few | Isolated particles | | 2 | Few | Slight scattered distribution | | 3 | Moderate | Clearly visible but not dense | | 4 | Many | High particle density | | 5 | Very many | Dense coverage | For asset owners and specifiers, the inclusion of
The , also known as the "pressure-sensitive tape method," is a critical quality control procedure used to assess the amount and size of loose dust remaining on blast-cleaned steel surfaces before painting. Even invisible dust can act as a barrier to adhesion, leading to premature coating failure through peeling, flaking, or underfilm corrosion. Importance of the ISO 8502-3 Test Even invisible dust can act as a barrier
The significance of this test lies in the "weak boundary layer" theory. If a coating is applied over a layer of dust, the adhesion is effectively between the coating and the dust, not the coating and the substrate. Upon curing or mechanical stress, this interface fails, leading to delamination.