Stress analysis and accelerated test design for interior light environments

A procedure for development of a simple, small-scale laboratory accelerated test based on the same light source used in the actual indoor application is described. This simple laboratory accelerated test can be used to evaluate durability of paints, coatings, or colorants used in art or graphic displays exposed to the interior lighting source. The steps used to develop the test include characterization of the light and thermal stresses for actual use conditions and applying the results to design an accelerated test. Examples for developing tests based on two different interior light sources are shown. Procedures for characterizing spectral power distribution, for calculating an irradiance acceleration factor, and for determining the uniformity of light and thermal stresses of the accelerated test are described. Results from measurements made using these procedures are used to establish the conditions for a practical small-scale laboratory accelerated test.