directory shall be protected by a laminated plastic cover and secured to the door with a suitable metal frame all to the approval of the Engineer. 9. Protective Coating/Painting a) Unless otherwise specified or approved, ferrous materials used in equipment and materials shall be shop galvanised. Internal components shall generally be electro-galvanised, external components shall generally be hot dip galvanised, according to BS 729 Table 1 – COATING WEIGHT of equivalent. b) Alternatively aluminium alloy may be used subject to obtaining the approval of the Engineer. c) Exposed surfaces of materials and equipment shall also be finish painted. Unless otherwise approved, finish painting shall be factory applied. Surfaces shall be cleaned, primed with two coats of rust inhibiting primer , finished with two (2) coats of enamel and baked (colour shall be selected by the Engineer), in accordance with approved manufacturer’s standard factory processes. d) Special finishes shall be provided where shown or specified. e) Site finish painting shall be two coats of high gloss enamel or stove enamel as appropriate, with primer and undercoat as appropriate and approved. f) Painting work and materials required herein and not otherwise specified shall be in accordance with applicable requirements specified under Division 31100. 10. Attachments To Structures a) General i) Appropriate types for material and conditions encountered and only as shown, specified or approved. ii) Adequate sizes for loads and forces involved. iii) Power actuated types in lieu of removable mechanical fastenings not permitted, unless otherwise shown or approved. iv) Insert of carbon steel for hangers and supports shall be placed and fixed prior to concrete pouring on slabs and beams. v) Cutting of post-tensioned structures shall not be allowed. vi) Cutting or welding to other structure for support shall be permitted only as and where shown, specified or approved for each specific condition or location. vii) Supporting piping or equipment by attachments directly to metal decking not permitted. viii) Items throughout shall be steel, hot-dip galvanised or corrosion resistant painted, plated or treated by approved methods. b) Continuous Supports i) Manufacturer’s standard prefabricated type of C-channel, roll-formed from steel strip of thickness not less than 1.6 mm in standard lengths for minimum of splices.