This part of ISO 105 specifies a method intended for determining the resistance of the colour of textiles of all kinds, except loose fibres, to the action of weather as determined by exposure to simulated weathering conditions in a cabinet equipped with a xenon arc lamp. ISO 105-B04 focuses on textiles (such as apparel) where the main evaluation criteria is the colour fastness. This method can be used to determine if a textile is wet light-sensitive. NOTE 1 – General information on colour fastness to light is given in Annex A. NOTE 2 – Textiles or technical textiles, which are permanently exposed to an outdoor environment and/or require mechanical testing (such as tensile strength determination) may be tested according to ISO 105-B10.