I think you have 2 sections mixed together:
505.2.2.1 Light reduction controls. Each area that is required to have a manual control shall also allow the occupant to reduce the connected lighting load in a reasonably uniform illumination pattern by at least 50 percent. Lighting reduction shall be achieved by one of the following or other approved method: 1. Controlling all lamps or luminaires; 2. Dual switching of alternate rows of luminaires, alternate luminaires or alternate lamps; 3. Switching the middle lamp luminaires independently of the outer lamps; or 4.Switching each luminaire or each lamp.
505.2.2.2 Automatic lighting shutoff. Buildings larger than 5,000 square feet (465 m2) shall be equipped with an automatic control device to shut off lighting in those areas. This automatic control device shall function on either: 1. A scheduled basis, using time-of-day, with an independent program schedule that controls the interior lighting in areas that do not exceed 25,000 square feet (2323 m2) and are not more than one floor; or 2. An occupant sensor that shall turn lighting off within 30 minutes of an occupant leaving a space; or 3. A signal from another control or alarm system that indicates the area is unoccupied.
There are exceptions for both sections (omitted for clarity). This is the 2009 IECC, I don't know if PA is different.
