The general lighting of any enclosed space 100 square feet or larger and has a connected lighting load that exceeds 0.8 watts per square foot, shall have multilevel lighting controls. Multilevel controls shall have at least one control step that is between 30 percent and 70 percent of design lighting power and allow the power of all lights to be manually turned off. A reasonably uniform level of illuminance shall be achieved by any of the following:
- Continuous or stepped dimming of all lamps or luminaires; or
- Switching alternate lamps in luminaires, alternate luminaires and alternate rows of luminaires.
- Lights in corridors.
- A space that has only one luminaire with no more than two lamps.