The purpose of this test is to determine the regular (parallel) luminous transmittance of the safety glazing material or multiple glazed units before and after irradiation. This is to determine whether or not it is adversely affected by exposure to simulated sunlight over an extended period of time. For this test, panels are measured for light transmittance before and after UV radiation for 100 hours.
Upon conclusion, the regular (parallel) luminous transmittance of the irradiated specimens shall not be reduced by more than 5% from its original value. A slight discoloration, noticeable only when specimens are placed on a white background, is permissible.