Road Signs: An Art and a Science

Roadside communication is a ubiquitous component of pedestrian and vehicle travel worldwide. The Romans deployed the first recorded roadside communications on the Appian Way in 312 B.C., using markers to indicate the distance to Rome. Fast-forward to today, travelers are inundated with messages ranging from government traffic and safety signs to advertisements on massive print or digital billboards.

In 2022, there were over 350,000 billboards in the United States, and the average size of a billboard was 14 feet high and 48 feet wide, providing 672 square feet of advertising space. But these mega-sized attention grabbers aren’t the only signs competing for attention on American roadways. Over 500 different federally approved traffic signs are being used in the United States, and it is estimated that tens of millions of these are deployed on our interstates, highways, streets, and rural roads. But there isn’t actually much of a competition between the giant flashy billboards and the somewhat mundane traffic sign.

Billboards vs Traffic Signs. Desperate attention grabbers vs subtle psychology wallflowers

Billboards scream for passersby to focus on them, whereas traffic signs are often just wallflowers – content not to be focused on. Visible, but not the center of attention. The very design of traffic signs encourages us not to study or be distracted by them.

The disciplines behind the design of traffic signs include standardization, ergonomics, visibility, simplicity, and psychology. A properly functioning road sign does not require the passerby to focus on the sign. Standard shapes, colors, placement, and size all work together over time to create an effect called priming. When someone “primes” something, it means to prepare it for something else. Think about the primer coat of paint or priming a pump. In psychology, priming is when exposure to a stimulus can later alter behavior or thoughts. Long before we are old enough to drive a vehicle, we observe road signs, and because the signs are standardized, our subconscious is primed to recall the message type of that sign instantly. Triangles, squares, and octagons, combined with red, green, blue, brown, yellow, orange, and white, trigger information primed in our minds through years of seeing traffic signs. We don’t need to actually read the sign to understand what the sign is about.

Traffic sign colors and shapes

Sign color themes include red, which means stop; yellow, which means caution; green, which indicates an exit ahead or other navigational information; orange, which indicates a warning – such as a traffic pattern change or hazard; and white, which means regulatory, e.g., speed limit. The traffic sign’s shape also conveys a message that has been primed in our minds. Octogans represent a regulatory message, most commonly stop, while diamonds are utilized for warnings. Square signs indicate a service, recreation, or point of interest, and rectangles serve as directional or navigation-related information.

Have you heard of Highway Gothic?

In addition to the psychology of colors and shapes, science has also impacted the font used on American street signs. Studies in letter clarity, capitalization, and font size and the recognition that standardization matters resulted in the adoption of Highway Gothic as the approved font for all road signs in 1948. Before that, signs around the country were a mixed bag of fonts selected by local or state leadership or even the individual sign maker.

Highway Gothic

Highway Gothic is a sans-serif typeface that has been used on highway signs in the United States since 1948. Theodore Forbes, an Illinois State Highway Department engineer, designed it. Forbes was tasked with designing a font that would be easily read at high speeds and in all weather conditions. He created Highway Gothic by combining elements of several existing fonts, including Futura and Highway Sans.

Highway Gothic quickly became the standard font for highway signs across the country. It is known for its bold, simple design and its high legibility. Highway Gothic is also one of the most recognizable fonts in the world, and it has been used in countless movies, T.V. shows, and commercials.

Clearview

Clearview is a sans-serif typeface that was developed in the 1990s as a replacement for Highway Gothic. Don Meeker and James Montalbano designed it, which was approved for interim use by the Federal Highway Administration (FHWA) in 2004.

Clearview was designed to be more legible than Highway Gothic, especially at night and in adverse weather conditions. It has a larger x-height, wider letter spacing, and more open counters. Clearview is also more similar to the fonts used in everyday life, such as Arial and Helvetica.

Despite its advantages, Clearview has not been widely adopted. Some states have used it on new signs, but many others have continued to use Highway Gothic. In 2016, the Federal Highway Administration (FHWA) announced that it was rescinding its interim approval of Clearview, and in 2018, Congress required the FHWA to reinstate the interim approval status. This decision means that states are no longer required to use Clearview on new signs and can continue using Highway Gothic.

Summary

Road signs are designed to communicate important information to drivers clearly and concisely. However, they are more than just simple traffic signals. Road signs also play an essential role in the psychology of driving. The psychology of road signs studies how drivers perceive and respond to road signs. This field of research draws on various disciplines, including psychology, cognitive science, and human factors engineering.

While it may seem counter-intuitive, when it comes to road signs, the less you have to look to understand, the safer it is for everyone on the roadways.