Penn State/USSC Legibility Study Helps Signshop Earn Variance

Practical application of USSC’s Penn State study helped Mercer Signs obtain variances

The following article originally appeared in the July 1999 issue of Signs of the Times magazine.

By Wade Swormstedt

Nearly four years ago, the United States Sign Council (USSC) embarked on an ambitious study with the Penn State Transportation Institute. Signs of different colors, sizes and illuminations were arranged around an oval track. Drivers then reported their ability to read the signs as they drove past. Two years and approximately $75,000 later, USSC’s investment culminated in “Sign Legibility: The Impact of Color and Illumination on Typical On-premise Signs,” which is highlighted by its Sign Legibility Index.

A year ago, Doylestown, PA-based Mercer Sign Co.’s Rick Crawford wanted to build a 90-square-foot, double-faced, internally illuminated sign for the Parkway Plaza in Upper Allen Township (near Harrisburg). Unfortunately, the township’s sign code only allowed a 25-square-foot sign.

Rick also wanted to build a 250-square-foot, 80-foot-high freeway sign for a Holiday Inn Express in the borough of Morrisville (near Philadelphia). There, freestanding signs are limited to 80 square feet, with a maximum height of 40 feet.

Rick needed variances. Fortunately, he has a law degree. More importantly, he’s the USSC board member who chairs its Legislation Committee, so he knew the Penn State study well. Using the Penn State study, and by taking photographs of what the signs would look like as proposed, and how they would appear if they adhered to the sign-code limitations, Rick succeeded in getting both variances.

“If you take the Sign Legibility Index, and integrate that with what you can do with the computer [to reproduce photographs from various distances], you get a far more professional, scientifically based presentation that minimizes guesswork and the subjectivity in the variance process,” Rick explains. Here is an abbreviated version of Rick’s recommended procedure. (Copies of the six-page study are also available from USSC.)

Of course, this process works much better if your proposed sign’s size and height are appropriate for the application. If so, the bottom-line message to the governing body is consistent: “If we follow your code, we will be installing an unreadable, unsafe sign.”

Using the index
The Sign Legibility Index provides the distance in feet from which 1-inch letters can be read. Distinctions are made for upper- and lower-case letters, as well as typestyles and type (if any) of illumination. The figures are directly proportionate, in that you would double the legibility distance for a 2-inch letter, quadruple for a 4-inch letter, etc.

Ironically, Rick also invoked the standard reaction-time of 10 seconds from the bane of all sign-legislation dogma, Street Graphics. The book’s “been widely accepted by planners and architects for 17 years,” he notes. The 10-second rule becomes part of later calculations.

So, for the Parkway Plaza sign, Rick’s presentation began with the basics. The street which the proposed sign would face has a speed limit of 45 mph, or 66 feet per second. Using Street Graphics’ 10-second standard, the proposed sign would need to be legible from a distance of 660 feet.

Next, Rick incorporated the Sign Legibility Index. For this sign, he looked at “Internal Translucent,’ with black, all-capital Clarendon letters. Consequently. the index value is 26, meaning that, under these circumstances, a one-inch letter can be read from 26 inches away.

Because the sign needed to be legible from 660 feet, Rick divided 660 by 26 to determine the size of letters necessary for sufficient legibility and reaction time. The quotient is 25, which means the sign’s letters needed to be 25 inches tall.

Given this information, Rick created proposed signs using both appropriate measurements and those that would strictly adhere to the sign code. These examples were then superimposed onto photographs taken from the 660-foot distance to simulate how they would appear to the motorist.

This last step was possible thanks to technology. Rick says this step required:

  • A digital camera (or photos) and a scanner
  • A design program, such as those produced by Adobe or Corel
  • A photo-processing program such as PhotoshopTM or PhotoPaint
  • A color printer (or large-format printer)

The results
Rick’s Upper Allen presentation lasted 3.5 hours due to other political factors. He estimates his sign-legibility presentation lasted only an hour. In Morrisville, he breezed through a 45-minute presentation. In each case, a three-person variance committee served as his audience.

“In Morrisville, it was so clear, there weren’t many questions,” Rick recalls. “In the past, invariably, someone would stand up and say ‘That sign’s too big,’ or ‘We don’t want to look like (whatever busy town is nearby)’. They couldn’t say that here because it was a scientific presentation.” Rick acknowledged that the Sign Legibility Index can essentially intimate that an entire sign code wrongly forces unsafe signs. However, he advises that sign-makers seeking variance should focus on how the city’s sign code creates a hardship only for the sign in question. Prior to his presentations, Rick worried that a town would say that granting him a variance would open the floodgates, but that didn’t happen.

“In each case, we were granted the larger sign,” Rick cheerfully reports. “And townships don’t give out variances lightly.” (The owners of Parkway Plaza, however, “traded” the pylon sign for some other building signage.)

The Penn State study was funded by USSC money, primarily from Sign World proceeds (the annual Atlantic City tradeshow in December) and USSC memberships. The association has committed approximately $100,000 to a follow-up study. Whereas the first Penn State study involved an artificial environment, USSC’s next study will take place in a “real-world” situation New signs with a slew of variables will be created for existing businesses, and the study will test motorists’ abilities to find the companies. Because details are being worked out, actual testing should begin in the fall.


Photo: © Copyright Mike Pennington

Wade Swormstedt

Wade Swormstedt

Wade is Executive Director of the Foundation for the Advancement of the Sign Industry. Formerly he was Editor and Publisher of Signs of the Times magazine.

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