Notes from 54th International STC Conference
Minneapolis, Minnesota, May 13-16, 2007

Road Signs: Finding Your Way in the Visual World

Jean-luc Doumont

The presenter is an independent contractor (JL Consulting) specializing in electronic publishing. http://www.principiae.be

Session Description: Through observation of one of its most common forms – road signs – this session explored basic concepts of visual communication. Road signs make a perfect source of learning about this topic because in most countries they are graphical. They use shape, color, and a variety of icons to convey meaning to motorists, cyclists, and pedestrians. But are they truly visual: that is, processed differently than words? Interpreted faster than word signs? More intuitive, more accessible, more universal? Are they even consistent – within a country and across countries? The lessons may be applied to visual representations at large and to the design of icons in particular.

• Clutter is worst enemy of clarity with road signs (e.g., 4 "busy" parking signs about when you can and can't park, be towed or not towed, during snow or not during snow, etc.). Way too much information to process in a 3-second park-or-not-park decision.
• Are road signs visual: words vs pictures?
• Are road signs consistent? Nationally/internationally
• Are road signs intuitive? Visual ambiguity again.
• Road signs in U.S. mostly use words; road signs in Europe mostly do not.
• Even in Europe, words are sometimes needed to qualify the sign's meaning, but then they are placed on another sign underneath. This is true in the U.S. as well—again, with a tendency toward more words.
• The heavy use of text (or words) is typical of a low-context culture. Everything is spelled out. "If it's not spelled out, it does not exist."
• In Europe, multiple languages makes text much less useful (and universal graphics more critical). Being economical with words helps address language issues.
• Road signs may not use words, but are they in fact truly visual?
• Sequence is literal (iconic), metaphorical (indexical), and conventional (symbolic). Photo of apple, Eve with apple, Apple Computer logo.
• Windsock in red triangle. Windsock is metaphorical for "side wind"; triangle is conventional for "warning."
• Road signs are largely conventional: like words, they require a dictionary to define the basic meanings of the shapes.
• Three Laws of Communication
   
• Adapt to your audience
• Maximize the signal-to-noise ratio
• Use effective redundancy (e.g., color, label, shape)


• Words can become noise if you do not understand the language displayed or if you have too little time to read what is written.
• Too much text creates a problem on road signs... just like on slides.
• On some road signs, words and picture are not redundant, but complementary. If the picture is processed before the words can be, this may confuse drivers (e.g., No Right Turn on Red, with right turn arrow X'd out in red).
• Consistency is simply not there internationally. Vienna convention, picture; U.S., words; Chile, both.
• Using circles with a red border for anything other than prohibition (e.g., Chile) creates ambiguity. For this reason, Chile is evolving toward a green-bordered circle for things that are permitted.
• Color should always be used with redundancy due to color blindness in the population.
• Mandatory vs special regulation sign creates confusion.
• Prohibitory signs unavoidably raise issues of double negation.
• Inappropriate qualifications are not limited to negations.
• Are road signs intuitive? Not always. In fact, not often! Visual representations are condemned to be concrete, which makes it difficult for them to be taken metaphorically. (e.g., how to prohibit ANY dog pictorially without getting into overly literal interpretations of the picture to mean only the specific breed depicted).
• Red suggests "don't" or "beware," so it has negative connotations. Don't use it for positive connotations.
• Depicting people is often a problem, because icons tend to also convey an attitude.
• Besides an attitude, representations of people may convey a gender, too.
• Much gender differentiation reflects subtle bias (not gender-blind), but sometimes differentiation is appropriate (e.g., restrooms).
• The essential difference between man and woman is hard to depict visually. At a Belgian Institute for Biogenetic Technology, the restrooms are marked XX and XY. Employees handle it well; visitors, well not always. J
• How do you represent a male person differently from a generic person?
• Road signs exemplify the strengths and weakness of visual communication.
• Pictures are more intuitive, more global than text, but metaphorical, and especially, conventional pictures are less intuitive and more rational (yet still global?)
• Pictures are ambiguous, condemned to be concrete: in this respect, a word is worth a thousand pictures.
• Schematic pictures convey abstract concepts better than realistic ones, yet they still carry "an attitude."
• Road signs and more road signs
• Other possible topics
   
• Realism vs schematics
• Arrows
• Road markings
• Traffic lights
• Zones (speed, ...)
• Pedestrian traffic
• Airport pictograms