Letter Style
Sign lettering for word messages on freeway guide signs is uppercase, with the exception of destinations (names of places, streets, and highways). All destinations on guide signs must be composed of lowercase letters with initial uppercase letters. Since the 1950s, the Highway Series alphabet has been used as the letter style for freeway guide signs. The Series E (Modified) alphabet is the letter style that is most commonly associated with freeway signs. In the late 1990s and early 2000s, TxDOT began researching the performance of a different alphabet for freeway guide signs. This alphabet (or font) is known as Clearview, and it is available in several different stroke widths. In 2003, TxDOT decided to implement Clearview as the standard font for all freeway guide signs (white on green, white on blue, and white on brown). All of the guide signs illustrated in this handbook use Clearview for the white part of the sign legend.
Clearview is available in several different stroke widths. Clearview 5WR is used for the white legend in Exit Direction and Advance Guide signs. Other styles of Clearview are used in other types of white on green signs. Figure 4‑9 illustrates the letters and numbers for Clearview 5WR.
Several unique features to the Clearview font make it different from the traditional highway alphabet:
- The loop height (or x-height) of the lowercase letters is greater than the 75 percent associated with the highway alphabet.
- The letter height is not independently specified for lowercase letters.
- The lowercase ascender letters (b, d, f, h, k, l, and t) are taller than an uppercase letter of the same height.
- The fractions are taller than an uppercase letter of the same height.
Figure 4-9. Clearview 5WR font for white legend on freeway guide signs.