Special lighting equipment for interstate transportation authority. (a) Notwithstanding any other provisions of this Chapter, an interstate transportation authority, as defined in this Section, in addition to headlights and other required or authorized lighting, may affix to the top front of its buses, 2 sets of lights, each containing up to 5 stationary lights, of different colors, including the colors white, yellow, blue, green and purple, and excepting, however, the color red. Such lights shall be located symmetrically above the windshield with one set of lights on each side of the headsign and may reflect an intensity of up to 64 candlepower each. Provided further however, that normally no more than 3 of such colored lights on each set of lights may be on or displayed at any one time. Such lights shall be stationary only, and shall not be oscillating, rotating, or flashing. The lights shall be displayed only on the top front of such buses, lighted in various combinations to indicate the route, the destination, and the express or local nature of the service.
     (b) As used herein, the term “interstate transportation authority” shall mean any body, agency, entity, or political subdivision created by compact between Illinois and another state, which is a body corporate and politic, and which operates a public mass transportation or transit system.