7-4-6: TRAFFIC-CONTROL SIGNAL LEGEND:
Whenever traffic is controlled by traffic-control signals exhibiting different colored lights, or colored lighted arrows, successively one at a time or in combination, only the colors green, red, and yellow shall be used, except for special pedestrian signals carrying a word legend. These lights shall indicate appropriate action and apply to drivers of vehicles and pedestrians as provided by applicable State law.
(Prior Code § 15-406)