Impact of sign orientation on on-premise commercial signs

Storefront signs are often the end point of the information system travelers use to navigate the street and highway system to arrive at commercial destinations. To test the supposition that larger parallel signs would be as visible as smaller perpendicular signs, a variety of on-premise signs were tested under real-world conditions to determine their detectability and legibility. Using an open-field research design conducted on public roadways in a small downtown area and along a commercial strip development zone, 120 older and younger subjects viewed signs during both day and night conditions, with particular attention paid to sign orientation, operationally defined as parallel (i.e., being parallel to the roadway) versus perpendicular (i.e., being perpendicular to or facing oncoming traffic). Sign orientation was investigated by comparing perpendicular signs to parallel signs that were two and three times larger than the perpendicular signs with proportional increases in copy size. Contrary to most sign codes, the results indicate that perpendicular signs are significantly more detectible and legible than are larger parallel signs.