Series 1900 Has Been Replaced By CC 486
In September 2025, as part of the rewrite of the Manual of Contract Documents for Highway Works, Series 1900 Protection of Steelwork Against Corrosion was replaced by CC 486 Protection of steelwork against corrosion. The notes for guidance, NG 1900, were replaced by CP 486. Contract-specific choices, previously set out in Appendix 19/1, now sit in the works-specific requirements.
Schemes tendered before the change may still be running under Series 1900. Our inspectors work to whichever specification applies to the contract.
What CC 486 Requires Of The Paint Inspector
CC 486 requires the paint inspector to be from an independent organisation and to hold at least a level 2 coating inspection qualification certified by ICorr, NACE, AMPP or Frosio. The paint inspector verifies surface preparation at least once before each coat is applied, and visually inspects the finished system.
What We Check
The inspection follows the work from the start of surface preparation to final acceptance, with every check recorded against the specification.
| Stage | Checks | Typical CC 486 requirement |
|---|---|---|
| Surface preparation | Preparation grade and cleanliness | Sa 2½, Sa 3 or St 3 to BS EN ISO 8501-1, as specified |
| Dust | Residual dust on the prepared surface | No worse than Class 1 to BS EN ISO 8502-3 |
| Soluble salts | Salt contamination of the prepared steel | Not more than 20 mg/m² |
| Lighting | Light at the workface | More than 500 lux |
| Ambient conditions | Steel temperature, dew point and relative humidity | No painting within 3°C of dew point or above 80% RH; checked before each shift and every 10 minutes |
| Film thickness | Dry film thickness of each coat | Measured to BS EN ISO 2808; not more than 50% above the specified minimum |
| Adhesion | Pull-off adhesion of the applied system | At least 5.2 MPa to ASTM D4541, at least once per 20 m² |
New Build And Maintenance Painting
On new steelwork, inspection usually starts at the fabricator's paint shop and continues through site coats and touch-up after erection. On maintenance schemes, the biggest risks are inadequate removal of old coatings and corrosion products, salt contamination on coastal and salted structures, and application in poor weather. We tailor the inspection frequency to where the risk lies.
Records You Can Rely On
Every inspection produces daily records of conditions, measurements and non-conformances, supported by photographs, together with the painting details the contract requires. That record is what protects the client and the contractor if the coating is ever questioned.