What the scale describes
ICRI Guideline No. 310.2R defines ten profiles, numbered CSP 1 to CSP 10, each represented by a physical replica chip. Low numbers correspond to light texture, such as that left by acid etching or light grinding. Middle numbers correspond to shot blasting at increasing intensity. High numbers correspond to scarifying, scabbling or heavy mechanical removal. The scale is visual and tactile: the inspector compares the prepared slab with the chips rather than measuring a single numerical roughness.
Why the profile is specified
The profile has two functions. It removes laitance and contaminants to expose sound concrete, and it creates the anchor pattern that a primer or coating needs for mechanical bond. The right profile depends on film build:
| Coating type | Usual direction for the profile |
|---|---|
| Thin sealers and primers | Low end of the scale |
| Thin-film and roller-applied coatings | Low to middle range |
| Self-levelling and broadcast systems | Middle range |
| Thick mortars, overlays and toppings | Upper range |
The exact range always comes from the technical data sheet. A profile that is too smooth limits bond; one that is too rough can leave peaks showing through a thin film or require more material to fill.
How a CSP is produced
- Shot blasting is the common method for large slabs and gives a uniform pattern whose intensity depends on abrasive size, speed and number of passes.
- Diamond grinding is used along edges, in small rooms and where a smoother profile is required.
- Scarifying and scabbling reach the upper range and remove old coatings or weak toppings.
- Acid etching gives only the lowest profiles and leaves residues to neutralize and rinse, so it is used sparingly.
Verification
Before coating, the prepared area is compared with the specified ICRI chips in several locations, including edges and corners. Other checks normally accompany the profile: cleanliness, absence of dust, moisture vapor emission rate or relative humidity per ASTM F1869 or ASTM F2170, and surface tensile strength per ASTM D7234 when the specification calls for it. SSPC-SP 13/NACE No. 6 groups these requirements for concrete preparation.
The profile is part of every preparation plan for our industrial epoxy flooring projects.