This recommended practice provides test methods and requirements to evaluate the suitability of plastic materials intended for optical applications in motor vehicles. These tests determine physical and optical characteristics of the material only. This recommended practice is not intended to cover the performance of plastics when molded and installed in a finished assembly. Performance expectations of such a finished assembly including its plastic components are to be based on tests of lamps, and so forth, as specified in SAE Standards and Recommended Practices for motor vehicle lighting lamps and reflectors.