Acá está:
Norma americana SAE:
HG Xenon HID headlamp
HR Halogen replaceable-bulb headlamp
Norma Europea EEC:
CR Low/high (dip/main) beam headlamp, tungsten filament
HC Low (dip) beam headlamp, halogen
HR High (main) beam headlamp or driving lamp, halogen
HCR Low/high (dip/main) beam headlamp, halogen
DC Low (dip) beam headlamp, gas discharge (HID Xenon)
DR High (main) beam headlamp or driving lamp, gas discharge (HID Xenon)
DCR Low/high (dip/main) beam headlamp, gas discharge (HID Xenon)
El código es más largo y dice otras cosas, acá está explicado
http://www.danielsternlighting.com/tech/lights/codes/codes.html