Before that question is answered, let’s talk about the history of highway sign fonts.
The main typeface seen on signs for many decades is called “Highway Gothic.” This typeface is defined by the Federal Highway Administration (FHWA) Standards Alphabets for Traffic-Control Devices, which was published in 1948.
There have been six variations of Highway Gothic.
In recent years, the standard typeface for guide signs for higher-speed highways is the Series E or Series E(M) of Highway Gothic.
In 2004, Penn State conducted research into a new style of typeface for roadway signage. The FHWA approved the interim use of a new typeface called “Clearview.”
The typeface was a decade in development, according to Penn State.
“Inadequate signing can be a contributing factor in roadway crashes. Although Clearview was intended to help older drivers, our studies show that the appreciable gain in reaction time provided by the new typeface will be achieved by drivers regardless of age,” Martin Pietrucha, a civil engineer and director of the University’s Science, Technology and Society Program stated in 2004.
Clearview is intended to make reflective signs more readable. It was found that when light reflected off of signs with the old Highway Gothic font, it could cause certain letters — like lowercase A, E, and S — to glow and become hard to distinguish, especially for elderly drivers.
The new font solved that problem by creating more space inside the letters, so the glow when headlights hit them does not cover them up, Penn State noted.
Pennsylvania was the very first state to implement new signs with the Clearview font. Later on, more states would start using it in their signs.
But only 12 years later, in 2016, the FHWA found that Clearview font had a bad effect on some negative contrast color orientations — like speed limit signs, for example. Those signs in particular have black lettering on a white background. The FHWA stated at that time that all new highway signs would be reverted back to Highway Gothic.
The FHWA made it clear that public safety is not at risk because some signs are in Clearview, however, and the organization is allowing those signs to remain up until they are worn out.
But then in 2018 the FHWA reinstated the approval of Clearview after saying it may not have had all the available information when it issued its termination.
As of 2022, you will see signs in both Highway Gothic and in Clearview.
Next time you’re on an interstate, especially in Pennslyvania, take a look at the highway directional signs. You will probably see the two fonts during your drive!