The Road to Street Sign Standardization


Every time we jump in our cars, we see countless road signs that we take for granted. The development of standardized road signage wasn’t an easy task, though; it took decades of work and saw its share of, er, bumps in the road. Let’s take a look at the development of the American system of road signs.

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Signs, Signs, Everywhere There's Signs

Although roads have been around for ages, road signs that offer instructions or directions are a surprisingly recent invention. When travelers were still getting around using horses and carriages, nobody gave much thought to signage. But after the advent of the car, it quickly became apparent that signs were needed to keep drivers from getting lost—or careening into each other.

It may seem odd now, but in those early days of driving, it wasn’t state or local governments who went around putting up signs; local auto clubs took it upon themselves to direct drivers. The Buffalo Automobile Club put up the first recorded network of road signs that gave directions to specific locations in 1905. Other auto clubs soon followed suit by either putting up their own signs or wrapping utility poles in colored bands that drivers could follow.

This system sounds like a triumph of the free market solving a problem without government intervention, but in reality it wasn’t all that great. While competition is often terrific, in this particular realm it just turned roads into confusing messes. Competing auto clubs all wanted to put up their own signs on main roads, and there was nothing to stop each one from displaying its signs. According to the Department of Transportation, some highly traveled roads hosted as many as 11 different sets of signs, each with its own format and conventions. State and local governments gradually began taking over the responsibility for signage, with Wisconsin taking the lead by putting up the first route markers in 1918.

White Means Stop

By 1914, it was pretty clear that these signs needed to be cleaned up and standardized around the country. Drivers needed to be able to quickly glance at a sign and tell its intent, which wasn’t possible if the signs were wildly different as one drove from region to region. The non-governmental American Association of State Highway Officials formed in 1914 and played a key role in helping push this agenda along.

Astonishingly, it took a full decade after the 1905 debut of road signs for the most basic sign of them all to make its first appearance. The first STOP sign didn’t adorn a public road until Detroit hung one in 1915. That early sign wasn’t the red-and-white octagon we all know, though; it featured black writing on a white sign.

Calls for the standardization of road signs became increasingly loud in the early 1920s, and events like the 1924 First National Conference on Street and Highway Safety began pounding out recommendations for national standards. Many of the concepts from these early meetings are still in use today. Regulatory groups like the AASHO shot for a two-pronged approach to signage that used both shapes and color schemes to relay just how important the information was. (For example, black writing on a yellow background in a diamond-shaped sign warned drivers to take caution.)

This idea of using shapes to relay information helps explain why we still have octagonal stop signs. Early recommendations suggested that circular signs be used for the most dangerous situations like railroad crossings, and octagonal signs would be used to indicate the next-most hazardous scenarios, like the need to stop. According to the Department of Transportation, these shapes weren’t just chosen at random, either. Making circular or octagonal signs requires more cutting and wasted scraps of metal, so thrifty road departments only wanted to use those shapes in less common situations where they were really needed, like intersections and railroad crossings.

The Standard Finally Arrives

As cars became increasingly common, attempts at uniform signage became more ambitious. In 1927 the AASHO published its Manual and Specifications for the Manufacture, Display, and Erection of U.S. Standard Road Markers and Signs to set standards for signage on rural roads, and the Manual on Street Traffic Signs, Signals, and Markings soon followed for urban guidance.

The major coup for standardization didn’t come around until 1935, though. That’s when the first edition of the government’s Manual on Uniform Traffic Control Devices appeared in a hand-mimeographed edition. The MUTCD is still the bible of American road signs, and the Department of Transportation still occasionally modifies it.

The 1954 revision of the MUTCD is probably the most memorable of these revisions because it established the familiar white-on-red STOP sign. Until that point the STOP sign had featured black writing on a yellow background, but the invention of a red finish that resisted fading allowed for the standardization of the idea “Red means stop!” across both traffic lights and signs.

Tulsa Cop Unyieldingly Supports New Sign

Tulsa police officer Clinton Riggs thought that not having a sign to force drivers to yield seemed downright idiotic. He’d been tinkering with an idea for a yield sign for years, but in 1950 he finally got around to putting one up. Riggs installed a keystone-shaped “Yield Right of Way” sign at Tulsa’s First Street and Columbia Avenue intersection in 1950. The intersection had been the city’s most accident-prone location, but the sign dropped it to the seventh most dangerous in six months. Other jurisdictions around the country rapidly adopted Riggs’ invention, and even though the shape changed, the sign made it into the 1955 MUTCD.