Crosswalk Usability

Everyone knows that New Yorkers pay attention to crosswalk signals... right?

So if you live in New York City, you may or may not have noticed that all the old crosswalk signals are gone. Instead of the spelling out WALK and DON’T WALK in type, the new signals use pictograms of a big red hand and walking person in a dotted outline of bright LED’s.

The new signal displays fit into the old, existing signal housing. And, by switching from incandescent bulbs to light-emitting diodes, the City notes, the new signals will both last longer and use less energy.

This piece in the New Yorker provides some hard numbers:

“The city is changing all eighty-five-thousand signs, at a cost of $28.2 million. The job started in 2000, in Queens; by February [2004] the [job] should be complete....

The idea is that the new ones, which rely on dozens of light-emitting diodes, or LEDs, will last six times longer than the old ones, which relied on two bulbs, and will save two million dollars a year in maintenance and electricity costs....

The brighter signs should be more visible to persons with partial sight. But, the author notes, the signals do have detractors:

“Among them many children, who sense that there is something patronizing about the hieroglyphs....

‘First of all, they’re really bright,’ Jacob said. ‘They hurt my eyes, even from, like, a block away. They make my eyes water. And, also, the first thing my sister could read was Walk/Don’t Walk.’ The three of them came to a corner: across the street, an upraised hand. They took a look, then crossed anyway. ‘The old one is just more original,’ Jacob went on. ‘Almost every other place has the Man and the Hand. Whenever I go anywhere else, it’s the Man and the Hand. Italy, France—they always have that. It’s un-unique. So I don’t really like it. Actually, most of my friends don’t like it.’”

The NYC page also claims that switching to “internationally recognized symbols” will make the signs “easily recognized by non-English speaking pedestrians.” I applaud the recognition and accomodation of non-English speakers in such a massive, city-wide initiative, but while the symbols may be “internationally recognized” in Western Europe, an open palm has different meanings in different cultures. For instance:

• In Japan an open palm in front of one’s face means “I don’t know,” “I don’t understand,” or “I am undeserving,” [source]
• In Greece, “extending the arm and hand (palm open) as if pushing something away from you is an age-old form of insult. In wars, Greeks would humiliate their prisoners by rubbing mud or fecal matter into their faces.” [source]
• And in Nigeria, pushing the palm of the hand forward with fingers spread is a vulgar gesture. [source]

With closs-cropped hair and boot-cut pants, the figure in white resembles other symbols used around here to indicate “male.”

The NYC page doesn’t mention it, but new crosswalk symbols are nationally mandated in the Manual of Uniform Control Devices published by the U.S. Department of Transportation. The Manual sets forth detailed design standards for traffic signage around the United States.

Recently, in San Francisco I discovered another variation I’d never seen before. In addition to the white man and red hand, the signals there feature a red countdown indicating the number of seconds remaining to cross the street. It turns out the countdown option was added to the Manual in 2000, and is slowly gaining popularity across the country. I was struck by the simple brilliance of it. The additional information is much more useful than the simple flashing hand or DON’T WALK. The latter always seemed to start flashing when one was halfway across the road. This calls to mind the scene from Rain Main when the austistic character stops walking in the middle of the road.

But that, apparently, is exactly when it is supposed to start flashing. The period of the countdown, flashing hand, and flashing DON’T WALK is known as the “pedestrian clearance interval”, the time for pedestrians to finish crossing, not to start crossing.

Local studies around the U.S. are finding that the countdown signals come at a price. While the countdown reduces the number of pedestrians who start running when the flashing DON’T WALK signal appears, the countdown seems to be interpreted to mean that it is OK to cross the street if there are enough seconds on the clock. Pedestrians are more likely to start crossing the street during the countdown than during the flashing DON’T WALK. This is contrary to the intent of the designers, and of the law.

Significant data has not yet been gathered on the countdown signal’s effect on the overall number of pedestrian fatalities.