Proportion-Based Format System for Freeway and Expressway Guide Signs

The Manual on Uniform Traffic Control Devices has grown much more complex since 1961, the year that a section on signs for freeways and expressways was added to the manual. Yet that growth has been reflected primarily in the addition of more regulatory signs and a great deal of qualifying language. The standards for sign legibility and layout have changed little; however, the complexity of the roadway environments and the demand placed on the system has changed substantially. This paper builds upon previous work by the writers, which proposed similar formatting for conventional road guide signing. The intent of the system proposed in this new work is to improve the consistency and uniform readability of freeway and expressway guide signs based on defined proportions for key dimensions including: border, figure and field relationship, and line space. This design scheme rests on a foundation of proportional relationships made uniform for all common applications based on the common dimension (“ $X$ ”) of the height of the primary legend’s lead capital letter.