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Midwest Seeing Red Over 'Green' Traffic Lights
theodp writes "Many municipalities have switched to LED traffic signals because they burn brighter, last longer and use 90% less energy than incandescent bulbs. But they also emit less heat, meaning they sometimes have trouble melting snow, causing problems across the Midwest. In Wisconsin, snow blanketed LED traffic lights in some towns, leading to crashes at intersections where drivers weren't sure whether to stop or go. The unintended consequences of the green technology were also identified as a 'contributing factor' in the death of an Illinois woman hit by a driver who blamed the snow-covered energy-efficient signal for giving the appearance of a normal green light instead of a left-turn signal. 'We can remove the snow with heat, but the cost of doing that in terms of energy use has not brought any enthusiasm from cities and states that buy these signals,' said the CEO of an LED traffic-signal manufacturer. 'They'd like to be able to take away this issue, but they don't want to spend the money and lose the savings.' In the meantime, some towns are addressing sporadic problems by dispatching crews to remove snow or ice from signals using poles, brooms, and heating devices." We were discussing these recently at the office — several folks in the building are red/green color blind and different street lights are differently distinguishable.
Oh that's right... we do! If you get to an intersection and the light isn't working or isn't visible, you treat it like a four-way stop.
idiot driver should be prosecuted since everyone knows the third light from the top is regular green and not a turn signal. i've seen intersections with broken lights before and people are very careful when they go and make sure the other guy is going to yield.
some people are always in a constant state of hurry and can't seem to wait a few seconds
In Wisconsin, snow blanketed LED traffic lights in some towns, leading to crashes at intersections where drivers weren't sure whether to stop or go
If you're not sure to stop or go, the answer is "stop". I can understand if it's dark and you don't see the traffic lights because they're covered with snow, but if the lights at the intersection aren't working, that doesn't mean the light is green. It means stop and go when it's safe to.
Maybe the lights need to take on a new form? What kind of problems would arise from coating each LED's sides with black paint (to replicate the duty of the indirect sun shades) and spacing the LEDs out so snow can pass through them? Or possibly shaping the LED or a cover as a cone shape so that it's harder to cover with snow?
Every time I start to have faith in humanity, I ruin it by driving to work between 7 and 8 am.
Oh, I thought the law was clear - when the signals are obscured or not working, stop at the intersection and then proceed as per a normal crossroads.
In the Illinois case, the green arrow was obscured just enough to appear to be a full green.
"I've never seen one obstructed by snow."
Yea, because you couldn't see it.
Genius. I would say RTFA, but you all you really need to do is read the summary.
Whale
I read this and I almost immediately thought "propaganda." Why? A appeal to fear based on a insignificant and easily fixable event, then attempting to tie the fear to larger political concepts. Fear change! Fear green! Equals death! Keep same! Same is warm! Same is reliable! Same is safe! You don't have to think about same!
Any sufficiently advanced influence is indistinguishable from control.
Red/Green colorblindness is nothing new; that's why the lights are standardized to have green at the bottom and red at the top. If you can't distinguish red from green, you can at least distinguish top from bottom. Why is that not a perfectly acceptable solution?
You see? You see? Your stupid minds! Stupid! Stupid!
I wonder if there is some other design factor that is causing this problem, beyond just the LED lights not putting out as much heat as incandescent ones. I live in Colorado and most of the traffic lights here (Denver area) now use LEDs. I don't believe I have ever encountered one that was clogged with snow or ice. Not to say it doesn't happen, but I wonder if the traffic lights here are simply designed differently (better covers/shielding, spacing, ?).
It seems like a simple solution would be a small heater incorporated into the LED lamp assembly that only turns on below a certain temperature. Better yet- perhaps a sensor could be used to detect if the lamp was covered, perhaps by reflectivity. This would probably still use a lot less electricity over the course of a year.
Why would the heaters have to use much energy? It sounds like they're not needed very often. You could automatically trigger them via external light/temperature sensors with some minimal processing or modify the red light camera software to trigger them. The only real downside is massively increasing the complexity of what is currently a very simple device.
A simpler answer might be to train people that they actually need to slow down if a traffic signal is not fully visible.
My town mistakenly ordered IED lights. These remove their own snow.
If Slashdot were chemistry it would look like this:Cadaverine
I live in North Dakota, we've had these LED traffic lights for years, and I cannot remember the last time I saw one totally snowed up. The shields that curve over the top of the traffic lights here do an adequate job of keeping the snow from coating the signals - including during the 3-day blizzard we had last week (I had to drive in it each of those 3 days, so trust me - they worked).
If they're not working in other states, than either their storms are somehow worse than ND's, or they've cheaped out on the snow shields that go over the top of the lights. I know which one I'd put my money on...
why don't they just angle the lenses downwards with less of a hood? problem solved.
I'm going out on a limb here, but you probably don't live somewhere that gets a lot of snow. Don't get me wrong, I think your idea would work in a lot of scenarios but not all of them. Where I live, we get the odd blizzard that puts a thick layer of ice and snow on everything. The wind pushes sticky snow at seemingly impossible angles preventing you from making out any lights or signs.
They say a little knowledge is a dangerous thing, but it's not one half so bad as a lot of ignorance. - Terry Pratchett
I was up in Fargo, ND visiting family for Christmas (yah shoor ya betcha) and a traffic light was out on a 6-lane intersection. Guess what? Everyone was calmly proceeding as if it was a 4-way stop. No drama, no retardation.
This whole thing is a non-problem. It's just that lazy journalists love it because it's "irony". It's not really ironic unless you're Alanis Morissette, but it makes for an easy, shitty space filler. Notice how in that story the SIGN is also covered in snow? ZOMG! We need heated road signs! Woe is me! Signs can sometimes become obscured by snow, the horror! The HORROR!
Coding with assembly is like playing with Legos. Coding an application in assembly is like building a car with Legos.
> The Inuits (you know, the guys whom entire daily universe is either Snow or Ice...) have over a hundred words just for snow.
Not really. That's an urban legend.
See
http://www.mendosa.com/snow.html
and
http://en.wikipedia.org/wiki/Eskimo_words_for_snow
Mod down people who tell people how to mod in their sigs
This is an opportunity, not a problem. Pack the lights with a nice long half-life radioisotope that we want to dispose of and let them melt their own snow. That way we still get all of the green benefits of LED over incandescent.
Help children born unable to swallow - www.tofs.org.uk
Red-green colorblindness should not affect the ability of a person to correctly observe a traffic light.
Under ideal conditions, you're correct. (But this whole article is about non-ideal conditions)
I have some color blindness and I can describe the problem I have. When it's raining and at night, it's difficult for me to tell a green light (non LED) from a nearby street illumination light (from a distance). I know that sounds crazy. Because it's dark, it's hard to see the rectangular enclosure, so I can't tell by the green-light's position. Only after it's changed to yellow then red can I tell which light was the illumination light and which was the green light.
And I can't just assume that lack of a yellow or red means I have the green, because it might be burned out.
The new LED lights use a different color of green that has a higher blue component that makes them completely obvious. Plus the LED lights are more intense than the other lights. This may be due to the light from an LED being a smaller set of frequencies (or a single one?) compared to a filtered incandescent, though I really don't know much about the physics of LEDs.
So, I expect it was mentioned in this context because when it's dark it's harder to tell the position of the green light against the dark enclosure, especially when there are nearby white lights. And the blue-green used makes them easier to see. At least that's my experience.
I don't think we need more rules, most of them could be relaxed, and relaxed a lot. The only evidence that I need is that, as I said, the majority of drivers relax the rules and drive as such already. I do not believe that it makes sense to set the bar for proper driving above what the average person is actually going to do on the road.
~40K dead Americans per year say you are wrong.
The real problem is NOT the people breaking the rules on purpose. They generally are paying attention, know the rules, and are ready to make adjustments. The problem is the people who either don't know the rules in the first place, or aren't paying attention. There is a HUGE difference between rolling through a stop sign at an empty intersection with unobstructed visibility, and rolling through without even looking because you were playing with your radio.
After 20 years of studying drivers and how accidents happen, I can tell you that you are wrong about them paying attention.
90+% of drivers are operating on autopilot. They are not paying attention and are just letting the autopilot handle everything. This is one reason that they take driving for granted and feel just fine texting or talking on a cell phone while running other drivers off the road. Most crashes happen when 2 inattentive drivers hit each other. If you have an inattentive drive and someone who is actually driving the driver avoids the person who is oblivious to the situation.
Who cares if I only bring my car down to second gear at stop signs? I am ready to stop. If there's another car who has right of way, I stop. If there's no other cars, I am slow enough to stop if I need to because someone else is blowing through, so no safety hazard is caused. If i have enough visibility to roll through at the speed that I am rolling through, and the situation isn't a dangerous one, then... how exactly does the rule make sense?
I care and so does anyone who avoids you hitting them because your "only dropping to 2nd gear for stop lights" becomes part of your autopilot and often you may not actually notice another car has already stopped at the intersection and is now proceeding to use their right of way when you blow the red/stop sign.
I have seen drivers (I hate to use this term for commuters who have somehow ended up behind the wheel and have no interest in teh art of driving) use this same argument and then drive and fail to notice other cars at intersections as they blow lights/signs. They still say that everything was clear and that there was no other traffic due to autopilot.
The advantage of your post is that it clarifies what the person who got killed did wrong. They went through an intersection while assuming other traffic would behave in a given way without even observing the traffic to see if this was likely. I really don't care if you have a green if it looks like an SUV coming up to a red and who will T bone you, is not slowing, don't just say "I have the right of way!" and head to your death. You will be in the right and just as dead as if you were not in the right.
If people cared about highway deaths we'd see a few things.
1. The news would report how many people died in the roads of their state the previous day and across the US.
2. Laws would begin to target bad drivers and not boogiemen like speeders and drunk drivers.
#2 sounds unbelievable so I should explain. When you are just as impaired using a cell phone as you are at the legal BAC level for DWI and only one of these has heavy legal ramifications... yeah, a boogieman has been created. Also if you research the criteria for a drunk driving crash you may be amazed at how a crash with no alcohol can still be classed as a drunk driving crash.
The police say that speed is the #1 cause of crashes. This is wrong. putting things where they do not belong is the #1 cause. If we wanted to reduce raod deaths the police would crack down on people rolling reds and stop signs, people commuting in the wrong lane, improper signal use, and other things which indicate bad drivers. Get the inattentive dummies off the road and watch the death rate plummet.