This Technical Specification describes a test method to measure the ultraviolet (UV) and visible (VIS) spectral transmittance in the wavelength range from 280 nm to 700 nm of coatings for exterior wood. From the spectral transmittance the transmittance of UV, VIS and the UV plus VIS wavelength range can be calculated.
It is applicable to free coatings films or coatings applied on a UV-transparent substrate.