Traffic Sign Color Schemes

Traffic signs have kept travelers in line for hundreds of years. Traffic signs actually predate the use of automobile and simple directional signs existed as far back as the Roman Empire. The invention of the automobile made more specific and visible traffic signs a necessity, and bright, noticeable colors were an easy way to convey messages from a distance. Here is some of the logic and facts behind traffic sign color schemes.

What the colors mean

The most commonly used traffic sign colors and meanings are actually borrowed from nature. For example, red, orange and yellow on traffic signs always represent some form of warning. When these colors are present in nature they are also used as a warning to indicate a poisonous animal or plant. More specifically, when it comes to signs, red means stop or indicates a forbidden area. Orange and yellow direct drivers to slow down and proceed with caution. Symbols are usually located in the center of these signs to clarify the warning. Meanwhile, green and brown signs are commonly used to provide specific information, like the distance to the next nearest city, or the presence of a landmark.

Color differences between countries

While red, yellow and orange are used almost universally on warning signs, green and brown informational signs are primarily used in the United States, Canada, Australia and New Zealand. The 1968 Vienna Convention on Road Traffic designated that all European motorways use a standard green and white or blue and white color scheme for signs, but off the motorways there is little continuity in the color schemes and symbols used for regular road and traffic signs. While many countries outside Europe still endeavor to follow the guidelines set by the Vienna Convention, there are nevertheless a wide array of variations on color scheme. Monochromatic symbol signs are also more popular overseas, in contrast to many of the text-based signs that are commonplace in America.

While warning colors like red, orange and yellow are used on traffic signs the world over, regular directional signs still lack one cohesive universal color scheme.