: A scale from 1 to 5 based on pictorial references.
Dust particles, particularly soluble salts, can act as corrosion initiators under the coating.
There has been some confusion regarding updates to this standard. iso 85023 dust level chart pdf updated
Very low dust level; minimal small particles scattered across the area.
The total amount of dust collected is rated on a numerical scale, often visualised on an : Class 1 (Clean): Almost no visible dust. Class 2 (Minimal): Very low quantity of fine particles. Class 3 (Moderate): Visible dust, moderate coverage. Class 4 (High): Significant amount of dust present. : A scale from 1 to 5 based on pictorial references
Match the dust density against the updated pictorial reference chart. Inspect the particle dimensions using the 10x illuminated magnifier. Why Downloading an Updated PDF Matters Dust Tape Test - Elcometer USA
The assessment is based on two factors:
The 2017 update maintains the core visual comparison method but ensures consistency with other modern surface preparation standards. INTERNATIONAL STANDARD ISO 8502-3
Press approximately 150 mm (6 inches) of the freshly exposed tape firmly onto the surface to be tested, touching the adhesive side only at the ends. Place the thumb across one end of the tape and move the thumb along the tape at a constant speed and pressure. Repeat this motion three times in each direction, with each stroke taking approximately 5 to 6 seconds. Very low dust level; minimal small particles scattered