1. Corrosivity Categories Under ISO 12944
Coastal and offshore industrial facilities reside in ISO 12944 C5 (Very High Corrosivity) environments where salt spray, extreme UV irradiation, and humidity aggressively attack structural steel.
2. Zinc-Rich Primers and Micaceous Iron Oxide (MIO)
Triple-layer barrier systems utilize a sacrificial zinc dust primer (cathodic defense), a micaceous iron oxide barrier coat that forces moisture along an elongated serpentine pathway, and an aliphatic polyurethane topcoat that resists UV discoloration and chalking.
3. Inspection, DFT Verification, and Adhesion Testing
Coating integrity is rigorously verified through wet and dry film thickness (DFT) magnetic gauge readings, high-voltage holiday pore testing, and hydraulic pull-off adhesion testing adhering to ASTM D4541 standards.
