Measurements to be independently witnessed. Check meter against standard shims and recalibrate regularly against a smooth steel reference plate. 4.1.5.11 Period between Over-coating Over-coating periods shall be strictly in accordance with the paint manufacturer’s printed requirements. Surfaces to be over-coated shall be clean and dry and prepared as required by the manufacturer. 4.1.5.12 Colour of Coats To enable clear identification of coats, the primer, intermediate and top coats shall be of different shades subject to the opacity of the final coat. The final coat colour shall be defined in the contract documents. The colour shall be as defined in the contract documents at the end of the warranty period. 4.1.5.13 Special Requirements • Connections: Where fabricated items are to be subsequently welded on site, the coating system shall not be applied within 150 mm of the weld. Where steelwork is galvanized, the galvanizing shall be removed from the weld area to provide a minimum of 75 mm clearance from the weld. • HSFG bolt connections: Coatings shall be carefully selected to ensure that the friction factor does not affect the ability of the connection to perform as designed. Friction type bolted connections shall be blast cleaned to Sa 2½ in accordance with ISO 8501: Part 1 with an agreed roughness. The friction surfaces can be coated with a material with a suitable friction factor. 4.1.5.14 Re-work Where testing indicates that the coating does not meet the requirements defined in the contract documents, the coating shall be made good by complete removal of all coats, preparation of the surface and re-application of the coating system in accordance with the contract documents. Where localised repairs are required, the coating shall be made good by local cutting- back of the coating, preparation of the surface and re-application of the coating system in accordance with the contract documents. 4.1.6 Reference Documents 4.1.6.1 Standards Reference Title BS 476 BS 5950 BS 6150 Fire tests on building materials and structures The structural use of steelwork in buildings Painting of buildings. Code of practice Page 26