Main Services / Coating, Painting Inspection & Corrosion Control
The most critical factor determining the service life of steel and industrial structures is proper surface preparation and corrosion protection. At CTI Inspection, we provide independent third-party painting, coating, and corrosion inspection services for steel structures, industrial plants, pipelines, and façade projects in accordance with internationally recognized ISO and ASTM standards.
Applicable Standards and Inspection Scope
Surface Preparation and Cleanliness Inspection
Up to 80% of coating performance depends on the quality of surface preparation. Our surface roughness, abrasive blasting grade, and salt/contamination analysis controls include:
- ISO 8501-1 / 2 / 3: Visual assessment of surface cleanliness grades (Sa 2½, Sa 3, etc.) and identification of surface/weld defects.
- ISO 8502-3 / 6: Assessment of dust and soluble salt contamination on surfaces (Bresle method).
- ISO 8503-2 / 5: Surface roughness profile determination and comparison (Profilometer / Comparator methods).
Corrosion Protection and System Design
ISO 12944 (1 - 8): Protection of steel structures against corrosion by protective paint systems, atmospheric corrosivity categories (C1–CX), and durability expectations.
Coating Thickness Measurements (Dry Film / Wet Film)
- ISO 2808: Measurement and evaluation of paint film thickness (DFT).
- ISO 2360: Non-destructive measurement of non-conductive coatings on non-magnetic basis metals.
- ISO 1461: Hot-dip galvanized coatings on fabricated iron and steel articles.
Adhesion and Mechanical Testing
- ISO 2409: Cross-cut adhesion testing.
- ISO 4624: Pull-off adhesion testing.
- ISO 2813: Determination of gloss values at 20°, 60°, and 85°.
- ASTM D5162: Discontinuity and holiday testing of non-conductive protective coatings (Spark Tester method).
Coating Degradation and Aging Evaluation
ISO 4628 (1 - 8): Evaluation of degradation of coatings—designation of quantity and size of defects, and of intensity of uniform changes in appearance (blistering, rusting, cracking, flaking, and chalking).
Frequently Asked Questions (FAQ)
1. Why is third-party painting and corrosion inspection necessary?
Errors in coating applications can quickly lead to severe corrosion and structural damage. Independent Type A Inspection Body oversight guarantees that abrasive blasting and painting processes are executed strictly according to technical specifications.
2. Why is the Bresle test (soluble salt test) performed?
Invisible soluble salts left on the surface cause osmotic blistering and premature coating failure. Conducted in line with ISO 8502-6, the Bresle test measures salt contamination levels prior to paint application.
3. What does the ISO 12944 standard provide?
ISO 12944 specifies the correct protective paint systems based on atmospheric corrosivity categories (from C1 to CX) and defines the expected durability range (Low, Medium, High, Very High) for the coating system.