When coupled with analytical techniques to evaluate the chemical evolution of polymer and can be use to predict the lifetime of polymer matrices as well as to develop either photo stable or photochemical degradable compound. Accelerated testing in SEPAP facilitates examination of photo-ageing process for polymeric materials.The rotating carousal for test specimen ensures uniformity of temperature and irradiance at exposed specimen surface. The SEPAP is equipped with four medium pressure mercury arc lamps in borosilicate envelops that emit discrete radiation at 290,313,365,405,436,547 and 579nm. Based on study of several thousands of polymeric formulations, these lamps were shown to induce the same photochemical processes as daylight while contributing significantly to the acceleration factor.