March 2026 · 5 min read
SA 2.5 — or 'Near White Metal' — is the most commonly specified surface preparation standard for industrial coating systems. Under ISO 8501-1, it requires that when viewed without magnification, the surface shall be free from visible oil, grease, and dirt, and from most mill scale, rust, paint coatings and foreign matter. Any remaining contamination shall show only as slight stains in the form of spots or stripes.
Surface cleanliness is only half the equation. Coating adhesion also depends on surface profile — the roughness created by abrasive blasting that gives the coating a mechanical key. Profile is measured using Testex Replica Tape and expressed in microns. Specifying and achieving the correct profile for the coating system is critical to long-term performance.
The most common failure mode is applying coating to a surface that has re-rusted after blasting. In humid tropical environments like Ghana, re-rusting can begin within hours of blasting if not coated promptly. Our process requires coating application within the maximum allowable time after surface preparation is verified — no exceptions.
Project Completion
Successfully delivered one of Ghana's significant private pipeline construction projects — from installation and mechanical systems through pressure testing and verified completion certification.
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Safety Excellence
Daily hazard analysis, fatigue management, and continuous training — how we've built a zero-incident track record across all major project sites.
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Technical Insight
Corrosion prevention, coating selection, and inspection protocols for petroleum storage tanks in West Africa's climate.
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