625 ILCS 5/12-901: Special lighting equipment.

Any religious organization bus may be equipped with a 4-lamp flashing signal system having unison flashing amber lamps, 2 at the front and 2 at the rear of the bus, mounted as high and as widely spaced laterally on the same level as is practicable. If such equipment is installed, (a) each lamp must be a sealed beam at least 5 1/2 inches in diameter and have sufficient intensity to be visible at 500 feet in normal sunlight, (b) the system shall be actuated only by means of a manual switch, and (c) there shall be a device for indicating to the driver that the system is operating properly or is inoperative.