Pedestrians at serious risk when drivers are 'permitted' to turn left, study says

Apr 02, 2013
An Oregon State University driving simulator tracks the eye movement and other behavior of drivers. Credit: Oregon State University

A study to examine driver behavior in permitted left turns has identified what researchers call an "alarming" level of risk to pedestrians crossing the street – about 4-9 percent of the time, drivers don't even bother to look and see if there are people in the way.

As opposed to a "protected" left turn, in which a solid green arrow gives a driver the complete right of way in a left-turn lane, a "permitted" left turn is often allowed by a confusing hodgepodge of signals, and drivers may have to pick their way through narrow windows of oncoming traffic.

This difficult driving maneuver, which is played out millions of times a day around the world, is fraught with risk for unwary pedestrians, who too often appear to be an afterthought.

The danger is much higher than had been realized, experts say.

"There are far more pedestrian crashes in marked than anywhere else on roads, and pedestrians already have a false sense of security," said David Hurwitz, an assistant professor of at Oregon State University. "This study found that one key concern is permitted left turns."

Technology can track the eye movements of a driver in a traffic simulator to determine what the person is looking at. Credit: Oregon State University

As they wait to turn left, sometimes taking a narrow opportunity to lunge into a stream of , drivers focus most of their attention on the and the traffic signal, rather than any pedestrians crossing the street, the research showed. The heavier the traffic, the less attention paid to pedestrians.

In a controlled analysis in a full-scale driving simulator that monitored specific , the engineers found that about one time in 10 or 20, the driver didn't even look to see if a pedestrian was there before moving into the intersection. This suggests a major level of risk to pedestrians, researchers said, if they assume that drivers not only will look for them, but will allow them to cross the street.

The problem is aggravated by "permitted" left turn signals that vary widely, from state to state and sometimes even from one city to the next. Such turns might be allowed by a circular green light, a flashing circular yellow light, a flashing circular red light, or even a flashing yellow arrow. More consistent national standards regarding the flashing yellow arrow were recommended as recently as 2009, but the process of upgrading signals across the nation takes time.

A "permitted" left turn in this driving simulator illustrates the complexity - watching the signal, watching the traffic, and watching for pedestrians all at the same time. Credit: Oregon State Universit

The danger is sufficiently high, the researchers concluded, that more states and cities should consider prohibiting permitted left turns while pedestrians are allowed to be in the crosswalk. In Washington County, Ore., traffic managers recently did just that, after receiving a high number of complaints about pedestrian-vehicle conflicts.

"In traffic management you always have multiple goals, which sometimes conflict," Hurwitz said. "You want to move traffic as efficiently as possible, because there's a cost to making vehicles wait. You use more fuel, increase emissions and waste people's time. The permitted left turn can help with efficiency.

"But the safety of the traveling public is also critical," he said. "Sometimes the goal of safety has to override the goal of efficiency, and we think this is one of those times."

Also of some interest, the study found preliminary evidence to suggest that the currently-mandated type of signal, which uses four heads instead of three, offers no change in . However, the cost to implement a four-head signal is about $800 more than retrofitting the three-head version, which is widely used around the nation. Many millions of dollars might be saved nationally by using the simpler signal.

The findings of these studies have been compiled in a report by OSU and Portland State University researchers to the Oregon Transportation Research and Education Consortium, which funded the research. They will also be presented this year at the Driving Assessment Conference in New York and the Western District ITE meeting in Arizona.

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More information: otrec.us/project/484

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TheGhostofOtto1923
1.4 / 5 (19) Apr 02, 2013
-Another study commissioned with tax dollars no doubt by liberal lawmakers who need to be passing new laws because it is the only way to show constituents that they are doing their jobs. Making laws that is.

This benefits conservative lawmakers as well because it gives them new laws to rescind. This is how democracy works.
ValeriaT
2.4 / 5 (5) Apr 02, 2013
The pedestrians cannot harm the drivers, the drivers can. So that drivers could be responsible for all pedestrian accidents in the same way, like in our country for example the driver who hits the car from back side is the culprit automatically.
TheGhostofOtto1923
1.4 / 5 (11) Apr 02, 2013
So that drivers could be responsible for all pedestrian accidents
No, pedestrians have the ultimate responsibility of protecting themselves. Only lawyers think otherwise.
like in our country for example the driver who hits the car from back side is the culprit automatically
Tailgaters are the scum of the highway and fair game for anyone (except me) who wants to lead them into the back of a stopped semi. Again, most lawyers would disagree.
ValeriaT
2.5 / 5 (6) Apr 02, 2013
The principle is, if you cannot brake safely, then you're driving too fast - with tailgater or without it. BTW Lawyers profit just from complex rules, not from simple principles, which are mandatory for everyone. Which is why, I don't really think, my proposal will be ever applied, because too many people need to keep their jobs.
TheGhostofOtto1923
1.7 / 5 (6) Apr 02, 2013
The principle is, if you cannot brake safely, then you're driving too fast. BTW Lawyers profit just from complex rules, not from simple principles which are mandatory for everyone. Which is why I don't think, my proposal will be ever applied.
And this is why insurance companies will soon make self-driving cars mandatory for anyone with any history of driving problems at all.
ValeriaT
1 / 5 (3) Apr 02, 2013
why insurance companies will soon make self-driving cars mandatory for anyone
Why not, but the owners of these cars should be still responsible for all injuries of pedestrians in similar way, like the owners of houses.
TheGhostofOtto1923
1 / 5 (3) Apr 02, 2013
why insurance companies will soon make self-driving cars mandatory for anyone
Why not, but the owners of these cars should be still responsible for all injuries of pedestrians in similar way, like the owners of houses.
And there will be far fewer such incidents wont there?
VendicarE
1.8 / 5 (5) Apr 02, 2013
The simple fact of the matter is that driving regulations are still too complicated and signs and indicator lights too complex, too varied in design and placement, and too confusing overall.

Turns may be prohibited at certain times of day, or for certain vehicle types, left turn signals may not exist or may be placed at different locations depending on the intersection.

To make a safe cross lane turn without adequate signals, the driver must look for pedestrians in front of him, pedestrians crossing the destination intersection, the lights facing him signs that may prohibit his turn, and other signals that may or not exist.

In many instances cross intersection turn signals may OK a turn while oncoming traffic is blocked, but the same signal at a different time of day will indicate the same turn status while oncoming traffic is not blocked.

These are all elements of exceptionally poor ergonomic design which undoubtedly costs hundreds of lives per year.
Jotaf
3.5 / 5 (4) Apr 02, 2013
Install roundabouts -- problem solved!

In a regular intersection, you have to look at 2 or 3 places if there are no traffic lights, or sit and wait for a greenlight. In roundabouts you only have to look and give priority to your left. It's a much smaller cognitive load for drivers.
Vyhea
4.5 / 5 (8) Apr 02, 2013
Another study commissioned with tax dollars no doubt by liberal lawmakers who need to be passing new laws because it is the only way to show constituents that they are doing their jobs. Making laws that is.

You got a bad attitude. Tunnel vision. Shouldn't be behind a wheel at all.
Vyhea
4.4 / 5 (7) Apr 02, 2013
Install roundabouts -- problem solved!

Good suggestion. Positive attitude.
antialias_physorg
5 / 5 (4) Apr 03, 2013
The danger is much higher than had been realized, experts say.

Some have already realized it. UPS, for example, has a no-left-turn policy.
No, pedestrians have the ultimate responsibility of protecting themselves.

No, because while drivers are required to learn the rules of the road, there is no similar test/permit for pedestrians. So pederstrians cannot be expected to follow (or even know) all the rules. Faulting them for mistakes due lack of non-required knowledge makes no sense.

And a pedestrian can be anybody. Old, hearing/sight impaired, young children, etc.
Faulting all of these automatically for being hit by cars is ludicrous.

...unless you want to start making laws allowing only those with a drivers license to leave their house on foot?
CreepyD
3.7 / 5 (3) Apr 03, 2013
I've seen much worse in the UK, such as Pedestrian crossings literally 10 yards after a turn when you would be looking the other way for oncoming traffic, and sometimes need to accelerate fast to get up to the traffic's speed - they are rediculously dangerous for pedestrians as all too often they cross even when cars are coming, fully expecting them to stop.
Seems like more standardisation is needed really on both sides of the pond.
QuixoteJ
2 / 5 (4) Apr 03, 2013
Mixing pedestrians with automobile traffic is a dangerous thing by nature, and we need to live with some risk here if we want to remain realistic. Not saying there isn't room for improvement, but I'm sure we're pretty close to optimal already.

I'd be more alarmed about this issue being a motivation to employ technology that has the ability to stop our cars under certain conditions.

Ironically, it appears that this study used technology similar to that which will cause more people to be hit by cars in the future (google glasses).
TheGhostofOtto1923
1.6 / 5 (7) Apr 03, 2013
No, because while drivers are required to learn the rules of the road, there is no similar test/permit for pedestrians. So pederstrians cannot be expected to follow (or even know) all the rules
Rule #1 - Pay attention. Rule #2 - Cars are dangerous and unpredictable. Rule #3 - Roads are dangerous places.
And a pedestrian can be anybody. Old, hearing/sight impaired, young children, etc
Rule #4 - Dont play in the street.
Faulting all of these automatically for being hit by cars is ludicrous
Well of course I didnt do this. Did somebody else do this?

WE ALL have the ultimate responsibility of protecting OURSELVES. Thats why the 2nd amendment is so important, and perhaps why euro subjects and serfs dont understand it.

You could eliminate vehicles altogether. This would make streets very safe.
antialias_physorg
5 / 5 (5) Apr 03, 2013
You could eliminate vehicles altogether. This would make streets very safe.

Pretty pointless arguments. typical black and white thinking.

The world is more complex than that and we, as a society, engage in tradeoffs all the time. Benefits of (some traffic) vs. dangers of (some traffic). While the benefits and dangers are inversely proportional with amount of traffic (infrastructure) they are not linearly so. There is an optimum - and an ever shifting one at that depending on technology applied and general societal awareness fostered for the dangers.

TheGhostofOtto1923
1.7 / 5 (6) Apr 03, 2013
Pretty pointless arguments. typical black and white thinking
This is what is known as a thought experiment. It is meant to explore absurdity.
The world is more complex than that and we, as a society, engage in tradeoffs all the time
Correct. And also phony political posturing and money-wasting law-passing and rescinding. Remember when the speed limit was reduced to 55mph? Remember carpool lanes? No, you dont.

Did you know some NY politician wants gun owners to have to buy liability insurance? No, you didnt.
Benefits of (some traffic) vs. dangers of (some traffic). While the benefits and dangers are inversely proportional with amount of traffic (infrastructure) they are not linearly so. There is an optimum - and an ever shifting one at that depending on technology applied and general societal awareness fostered for the dangers
Blahblah. Blah?