ISO 2135 specifies an accelerated test method for assessing the fastness, using artificial light, of coloured anodic oxidation coatings on aluminium and its alloys.

For evaluating light fastness on exterior exposure, only outdoor exposure under conditions comparable with actual service is completely satisfactory.

Accelerated testing is suitable as a quality-control test of coloured anodic oxidation coatings whose light fastness number has already been established by means of outdoor exposure testing.

The method is applicable to coloured anodic oxidation coatings on aluminium and its alloys produced by any means and for any purpose.

However, the method is not suitable for the measurement of coloured coatings with a light fastness number already established by means of outdoor exposure testing and of less than 6.