This Approved Method applies to luminaires having a total field angle greater than or equal to 10 degrees. The method applies to luminaires that utilize a variety of light sources, including tungsten filament, tungsten-halogen, and high intensity discharge (HID) lamps. It does not apply to luminaires using low pressure sodium (LPS), fluorescent, or solid state lighting (SSL) sources. (For luminaires where the total field spread is less than 10 degrees, refer to ANSI/IES LM-11-20.1 Photometric testing of reflector-type lamps is described in ANSI/IES LM-20-20.2)