There must be big plans in place to celebrate the 75th anniversary of this lifesaving technology, right?

AD

“If I said, ‘No,’ ” McGuirk replied, “would you be offended?”

I’ve decided to take that as an invitation to host my own pedestrian party right here. It starts with a stroll down memory lane with the Federal Highway Administration’s Bruce Friedman, who notes that even car traffic signals are a relatively recent invention. In the early 1900s, policemen would stand on top of towers in busy intersections and direct vehicles with semaphore, he says.

AD

To get a sense of the history of pedestrian signals, he recommends looking through old copies of the Manual on Uniform Traffic Control Devices, first released in the 1930s. The earliest editions of this scintillating book are mum on the issue of what to do about people on foot. But by the late 1940s, interest surged. With each update, there’s a new take on what the signals should look like — the color orange was added to the mix, and symbols replaced words.

AD

That switch happened, Friedman explains, because “people had a hard time understanding the meanings of ‘walk’ and ‘don’t walk.’ ” When “don’t walk” began to flash, people would retreat back to the curb. The results weren’t any better in experiments using “start” and “don’t start.”

What finally seemed to get the message through to pedestrians, he says, was the countdown signal, which was introduced in the manual in 2003.

AD

D.C. jumped on that technology, McGuirk says, after getting rave reviews when a few countdowns were installed on the Mall. Washington was one of the first cities to make those types of signals standard, and the first to switch entirely over to LED bulbs, he brags.

AD

The innovations have continued with the introduction of “leading pedestrian intervals,” which flip the walk sign on a few seconds before the green light for cars. That gives pedestrians a chance to establish a position in the crosswalk and gives motorists a cue to get ready, McGuirk says.

Another cool development: “HAWK” (High-Intensity Activated crossWalK) beacons that let pedestrians halt road traffic without a traditional stoplight. In most spots, you trigger the red light with a button. But one intersection (16th and Jonquil streets NW) uses a camera that can sense when pedestrians are around.

It’s all definitely a step up from that original signal in 1939.