This standard specifies requirements for glazing equipment manufactured before September 1@ 2006 for use in motor vehicles and motor vehicle equipment@ and specifies requirements for motor vehicles manufactured before November 1@ 2006 and for replacement glazing for those vehicles. A manufacturer may@ at its option@ comply with 49 CFR 571.205 instead of this standard. Purpose. The purpose of this standard is to reduce injuries resulting from impact to glazing surfaces@ to ensure a necessary degree of transparency in motor vehicle windows for driver visibility@ and to minimize the possibility of occupants being thrown through the vehicle windows in collisions.