1.1 This standard specifies a method for determining the resistance of paint film and allied products to conditions of high humidity. 1.2 The method is applicable to coatings both on porous substrates such as wood, plaster and plasterboard, and on non-porous substrates such as metal. It provides an indication of performance likely to be obtained under severe conditions of exposure where continuous condensation occurs on the surface. 1.3 The procedure may reveal failures of the coating (including blistering, staining, softening wrinkling and embitterment) and deterioration of the substrate