39:4-105.Ā  Color system
Traffic signals or signal devices shall conform strictly with the provisionsĀ  of this article.

A three-color system shall be used;Ā  red, amber and green.Ā  Green means permission for traffic to go, subject to the safety of others or the specific directions of an officer, official sign or special signal.Ā  Red means traffic to stop before entering the intersection or crosswalk and remain standing untilĀ  green is shown alone, unless otherwise specifically directed to go by anĀ  officer, official sign or special signal.Ā  Amber, or yellow, when shown aloneĀ  following green means traffic to stop before entering the intersection orĀ  nearest crosswalk, unless when the amber appears the vehicle or street car isĀ  so close to the intersection that with suitable brakes it cannot be stopped inĀ  safety.Ā  A distance of fifty feet from the intersection is considered a safeĀ  stopping distance for a speed of twenty miles per hour, and vehicles and streetĀ  cars if within that distance when the amber appears alone, and which cannot beĀ  stopped with safety, may proceed across the intersection or make a right orĀ  left turn unless the turning movement is specifically limited.

All other uses of green, red, amber or yellow lights so located as to be confused with traffic signals shall be discontinued.
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