This SAE Recommended Practice applies to motor vehicle Forward Illumination Systems which use light generated by discharge sources. It provides test methods, requirements, and guidelines applicable to the special characteristics of gaseous discharge lighting devices which supplement those required for forward illumination systems using incandescent light sources. The document is applicable to integral beam and replaceable component discharge forward lighting systems. This document is intended to be a guide to standard practice and is subject to change to reflect additional experience and technical advances.