ISO 27448:2009 deals with fine ceramics.
ISO 27448:2009 specifies a test method for the determination of the self-cleaning performance of materials that contain a photocatalyst or have photocatalytic films on the surface, and which are usually made from semiconducting metal oxides such as titanium dioxide.
This method is used to measure the water contact angle under illumination with ultraviolet light, which is one of the indices influencing the self-cleaning performance of photocatalytic materials.
ISO 27448:2009 does not include water-permeable substrates, rough surfaces which do not have exposed water droplets, highly hydrophobic, powder or granular materials, or visible light-sensitive photocatalysts.