This specification applies to the supply, on the basis of performance, of flat enamel for interior use. Enamel of this type is normally intended for use without primers and undercoats on surfaces such as dried and aged masonry, asbestos cement sheeting, set plaster, and plater sheets. However, timber and metal should be suitably primed, and surfaces suspected of being highly alkaline or highly porous, or of variable porosity may require sealing with a suitable sealer.