Cancels and replaces the first edition (1976). Specifies methods of exposing plastics to solar radiation, either by direct exposure to natural weathering (Method A), to indirect solar radiation by modification of its spectral distribution with glass to simulate ageing of plastics behind building or automotive window glass (Method B), or to solar radiation intensified by the use of Fresnel mirrors to achieve acceleration of the weathering processes (Method C). Specifies the general requirements for the apparatus and operating procedures for using the test methods described and methods for determining radiation dosage. Applicable to plastics materials of all kinds and to products and portions of products.