If that trade doesn’t feel quite right, consider that this isn’t the only place where traffic engineering assumes some road users will break the law. It seems that this piece of traffic engineering has traded an increase in illegal behavior that doesn’t increase pedestrian risk for a decrease in illegal behavior that has the potential of serious consequences. The danger comes during the “solid hand” phase, when the lights change for the cars. But does it work? Compared to traditional pedestrian signals, those with countdown timers have more pedestrians entering the intersection after the signal switches to the “flashing hand” phase, but less pedestrians remaining in the intersection when the signal reaches the “solid hand” phase.Įven though it’s against the law to enter a crosswalk when the hand is flashing, being in the intersection during that phase does not increase a pedestrian’s risk of getting hit. Giving the late entry pedestrians a timer lets them know how long they have to finish crossing the street. Unfortunately, when a walker overestimates the distance he can cover before the signal turns to a solid hand, he ends up in the wrong place at the wrong time. Someone with a fast walking pace around 4 MPH could conceivably step onto the sidewalk well after the signal switches from “walking person” to “flashing hand” and still cross the street before the 2 MPH walker who started during the “walking person” phase. The length of the “flashing hand” phase of the pedestrian signal is based on a 3.5 feet per second walking pace (a bit over 2 MPH). Adding the timer is like saying, “We know they’re going to start crossing the street after they’re supposed to let’s just add a timer so they know how long they have until they get run over.” However, I prefer to think of it not as bad behavior, but as under-informed behavior. You could argue that traffic engineers just caved to bad behavior. Crashes decrease in intersections that switch to countdown signals. They are designed to, in government language, “help pedestrians make better crossing decisions at signalized intersections.” Based on crash data, they seem to work. That’s where countdown pedestrian signals come in. Sometimes people guess wrong on how much time they have and end up in the middle of the intersection when the lights change. This system works reasonably well, except during the flashing hand phase, when pedestrians are tempted to start crossing in hopes that they’ll make it across before the flashing hand turns solid. Solid hand symbol: Why are you still in the crosswalk?.Flashing hand symbol: Don’t start crossing the street, but if you’ve already started, go ahead and finish.Walking person symbol: You can start crossing the street now.My apologies in advance for stating the obvious: Who is right on this?Ī: By a show of hands, how many of you, when you see a pedestrian traffic signal with a countdown timer, look at the remaining seconds, calculate whether you can cross the street that fast, and then make a run for it? You can all put your hands down now.īefore we get into pedestrian signals with countdown timers, let’s do a quick refresh on a traditional pedestrian signal. They seem to think that they are okay to start across as long the seconds are showing. I see pedestrians constantly starting to cross when the red hand is lit and the seconds are showing. My understanding is that when a pedestrian comes up to the corner to cross the street and the red hand light is flashing, they are not supposed to start across. Q: I have a question on traffic signals for pedestrians.
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