5 ms·

Is it possible to design a better stop sign?

24 points by cwan 16y ago

btilly 16y ago
I'm curious. Stop signs are red. A lot of the environment around them is green. And about 10% of men have difficulty telling red from green. Would a different color work better?
- Qz 16y ago
  Red is also a harder color to differentiate in low light conditions. I would say hot pink.
- ubernostrum 16y ago
  And about 10% of men have difficulty telling red from green. No. "Red-green colorblindness" is an inaccurate and misleading name; "green weakness" is a better description, and is what every doctor I've talked to uses as a casual name for the condition. The best explanation I know of is to imagine the following: you're looking at a screen onto which is projected a square of pure red. Then, gradually, green is added, which will eventually cause the square to appear yellow (yes, red and green make yellow). When a person with "normal" color vision sees it as yellow, a person with the common forms of green weakness would still see it as a bit orange-ish. In other words, the common form of "red-green colorblindness" doesn't cause a red sign to look green, or a green light to look red, or grass to look red, or any of that stuff. It mostly causes problems in the yellow part of the spectrum (one reason why I tend to avoid earth tones).
  - BoppreH 16y ago
    It might have been a different condition, but I could swear I saw a page of a guy who made a side by side comparison of images that for him looked the same. I clearly remember two pictures, one depicting very bright red berries on a bush and other with the berries colored green, almost invisible now.
    - zephyrfalcon 16y ago
      Maybe this page: http://critiquewall.com/2007/12/10/blindness http://critiquewall.com/2007/12/10/blindness
      - BoppreH 16y ago
        Exactly that one. Thanks. So, is that a different condition?
        zephyrfalcon 16y ago
        Hmm. I'm not sure. I am R/G colorblind myself, and I don't confuse red and green traffic lights; they look completely different to me. On the other hand, some devices use LEDs that can be red or green (like the Nintendo DS; red means it's time to charge the battery), and I can't tell them apart at all. Also, for what it's worth, on my MacBook the images in the aforementioned blog post look almost the same to me. But I looked at them on a different computer as well, a netbook where I tweaked the color settings, and there they don't look the same at all. (I still can't pass the Ishihara test on that one though... :-)
  - nitrogen 16y ago
    I have a relative who doesn't perceive red as a color at all, only as a change in brightness when it is added to or removed from an image. Presumably he still perceives red lights as having some sort of color and not just gray, but it isn't red.
    - ubernostrum 16y ago
      Problems with brightness usually are a result of protanopia or protanomaly, which are much rarer than what most people mean by "red-green colorblindness" (which is usually deuteranomaly).
  - btilly 16y ago
    Looking at http://colorvisiontesting.com/color2.htm http://colorvisiontesting.com/color2.htm confirms what you say, but also confirms that there are many kinds of color-blindness and about 2% of men really can't tell the difference between green and red. Not as many as I said, but still a significant fraction.
    - ubernostrum 16y ago
      There are three basic types of colorblindness, and two of them -- dichromacy and trichromacy -- break down into three subtypes each. When people say "red-green colorblindness" they almost always mean deuteranomalous trichromacy (AKA deuteranomaly, "green weakness"), which is A) by far the most common form of "colorblindness", B) for practical purposes mostly affects the yellowish part of the spectrum and C) is typically so mild that most people who are deuteranomalous could go their whole lives without ever knowing it. The problem is that the average person doesn't ever realize this -- just as you apparently believed that the most common form of colorblindness led to an inability to distinguish red from green -- and so there are a huge number of misconceptions floating around which, as one of those 6% of males who are deuteranomalous, I do my best to clear up whenever possible.
- Keyframe 16y ago
  Yes, http://en.wikipedia.org/wiki/Chartreuse_(color)#Chartreuse_in_popular_culture http://en.wikipedia.org/wiki/Chartreuse_(color)#Chartreuse_i... Chartreuse would: Since about 1973, a sort of fluorescent chartreuse yellow has been adopted as the color of fire engines in parts of the United States and elsewhere. The reason behind this is that chartreuse fire engines are more visible on the streets than the traditional red fire engines, especially at night... However, everyone is conditioned to a semaphore scheme of GREEN go, RED stop, so I guess that can't be conditioned out.
  - pbhjpbhj 16y ago
    Chartreuse is basically the fluorescent green colour of 80s (and now!) fashion. Strong fluorescent colours, particularly the pink, do terrible things to my eyes in some circumstances particularly when they have contrasting writing on them.
lincolnq 16y ago
Wow, I didn't know that roundabouts are more efficient than other intersection types. That's really cool. (Now I want to build a traffic simulator that can simulate that effect...)
- rbritton 16y ago
  There's a roundabout by my business that they put in about two years ago. There's also a large trucking hub that has to go through it to access the interstate. Whoever designed it didn't consider this factor when putting it in, so it's too small for a semi truck to make it through. They just drive over the center.
  - pbhjpbhj 16y ago
    In the UK we often have smaller roundabouts, called "mini-roundabouts", they're designed with a small hump of circular horizontal cross-section that can easily be driven over by large vehicles. It's part of the design that trailer towing vehicles or wide vehicles can simply drive over the top if necessary.
- JoeAltmaier 16y ago
  Hm. We have one in town - 3 roads, 2 lanes, one of which doesn't go all the way around. A "map" posted 100 yards in front listing all the options. I've seen people stop to look at the map before going on. This is not more efficient.
  - nitrogen 16y ago
    Take down the map and it probably would be. We had an intersection in my city with three roads/six entrances. Originally it was a 6-way stop, but it had very poor visibility and there were numerous accidents. Now, it's a roundabout, and traffic flows much more smoothly (I've never seen more than three cars waiting to enter, and it usually takes about 5-10 seconds per car). Multi-lane roundabouts are probably more confusing than single-lane, as well, but if the street is primarily traveled by locals, give them some time to learn it and speed should pick back up.
deleted 16y ago
[deleted]
lutorm 16y ago
The better stop sign would be no stop sign. The preponderance of stop signs on US roads is one of the most infuriating parts about American road engineering. (Along with such a large number of signs that it is not humanly possible to process them all when traveling at vehicle speeds.) It really does condition drivers to look for signs instead of other people. If you run a stop sign, you'll get fined even if nothing happens. If you stop at a stop sign and then in blissful ignorance ram someone who didn't, no harm comes to you (unlike to the other person). The book "Traffic" by Tom Vanderbilt is an interesting read about some counterintuitive things about how traffic works and about how differently engineers in different countries approach safety. I can highly recommend it. EDIT: One of the most fascinating stories in the book is about how they redesigned some big 5-way intersection with a traffic light in some central square of a Dutch city by just removing everything and leaving a big empty square with some lines painted indicating the roundabout. Crashes went down, and traffic flow improved, because drivers were forced to pay attention to figure out how the whole thing worked. Experience seems to indicate that the "safety" measures usually taken in the US (widening roads, removing pedestrians, etc) are totally counterproductive because they send subconscious signals to the drivers that this is a speedway which causes everyone to drive faster and pay less attention, which makes crashes more severe (not to mention relegates pedestrians, bicycles and other alternative means of transport to second-hand status.)
- nkurz 16y ago
  I don't disagree, but your phrasing seems odd considering that the linked article is written by the same Tom Vanderbilt who wrote "Traffic". This might imply that it already takes your points into consideration?
  - lutorm 16y ago
    I'm not necessarily criticizing the article, just voicing my immediate comment on the topic in the title.
- thrdOriginal 16y ago
  Completely anecdotal: a friend of mine moved here (US) from Germany ~ 5 weeks ago, and she was driving my car with me in the passenger seat. Just as I was thinking "she is a safe defensive driver," she approached a stop sign and to my shock did not stop, but slowed down only to continue on her way much like a yield sign. I freaked out a little in the vein of "Stop signs here are not suggestions!" She responded with points simiar to yours (and the articles'): there are way too many stop signs in the US, it is the most expensive part of driving (fuel-wise), and it essentially teaches people not to be thoughtful, cautious drivers. Now while driving I'm constantly thinking "what a wasteful stop sign."
lukev 16y ago
When I drive I look as much for shape and color as the actual words. To sell me on the idea of a new stop sign, you'd have to demonstrate that not only was the new design objectively better, but it is objectively better by a large enough margin to offset all the additional errors caused by drivers who aren't trained to look for a different design.
JoeAltmaier 16y ago
Keep designing and we'll end up in a hole. Look at brake lights. First just two little lights. Then big, reflective lights. Then another light in the rear window. Then one on the mirror. Soon every car will look like the Vegas strip. Why all this inflation? Because we get lazy the more obvious the light becomes? How about one tiny bulb, that you have to really strain to see. Cheaper, keep us all "in the drivers seat" instead of making our way to work in a zombie state.
- potatolicious 16y ago
  The big, reflective lights are there partially due to the fact that we're using LEDs for brake lights instead of bulbs. The advantage here is that LEDs respond much faster than bulbs, which have a significant delay between power applied vs. light generated.

24 points by cwan 16y ago

I'm curious. Stop signs are red. A lot of the environment around them is green. And about 10% of men have difficulty telling red from green. Would a different color work better?

Qz 16y ago
Red is also a harder color to differentiate in low light conditions. I would say hot pink.
ubernostrum 16y ago
And about 10% of men have difficulty telling red from green. No. "Red-green colorblindness" is an inaccurate and misleading name; "green weakness" is a better description, and is what every doctor I've talked to uses as a casual name for the condition. The best explanation I know of is to imagine the following: you're looking at a screen onto which is projected a square of pure red. Then, gradually, green is added, which will eventually cause the square to appear yellow (yes, red and green make yellow). When a person with "normal" color vision sees it as yellow, a person with the common forms of green weakness would still see it as a bit orange-ish. In other words, the common form of "red-green colorblindness" doesn't cause a red sign to look green, or a green light to look red, or grass to look red, or any of that stuff. It mostly causes problems in the yellow part of the spectrum (one reason why I tend to avoid earth tones).
- BoppreH 16y ago
  It might have been a different condition, but I could swear I saw a page of a guy who made a side by side comparison of images that for him looked the same. I clearly remember two pictures, one depicting very bright red berries on a bush and other with the berries colored green, almost invisible now.
  - zephyrfalcon 16y ago
    Maybe this page: http://critiquewall.com/2007/12/10/blindness http://critiquewall.com/2007/12/10/blindness
    - BoppreH 16y ago
      Exactly that one. Thanks. So, is that a different condition?
      - zephyrfalcon 16y ago
        Hmm. I'm not sure. I am R/G colorblind myself, and I don't confuse red and green traffic lights; they look completely different to me. On the other hand, some devices use LEDs that can be red or green (like the Nintendo DS; red means it's time to charge the battery), and I can't tell them apart at all. Also, for what it's worth, on my MacBook the images in the aforementioned blog post look almost the same to me. But I looked at them on a different computer as well, a netbook where I tweaked the color settings, and there they don't look the same at all. (I still can't pass the Ishihara test on that one though... :-)
- nitrogen 16y ago
  I have a relative who doesn't perceive red as a color at all, only as a change in brightness when it is added to or removed from an image. Presumably he still perceives red lights as having some sort of color and not just gray, but it isn't red.
  - ubernostrum 16y ago
    Problems with brightness usually are a result of protanopia or protanomaly, which are much rarer than what most people mean by "red-green colorblindness" (which is usually deuteranomaly).
- btilly 16y ago
  Looking at http://colorvisiontesting.com/color2.htm http://colorvisiontesting.com/color2.htm confirms what you say, but also confirms that there are many kinds of color-blindness and about 2% of men really can't tell the difference between green and red. Not as many as I said, but still a significant fraction.
  - ubernostrum 16y ago
    There are three basic types of colorblindness, and two of them -- dichromacy and trichromacy -- break down into three subtypes each. When people say "red-green colorblindness" they almost always mean deuteranomalous trichromacy (AKA deuteranomaly, "green weakness"), which is A) by far the most common form of "colorblindness", B) for practical purposes mostly affects the yellowish part of the spectrum and C) is typically so mild that most people who are deuteranomalous could go their whole lives without ever knowing it. The problem is that the average person doesn't ever realize this -- just as you apparently believed that the most common form of colorblindness led to an inability to distinguish red from green -- and so there are a huge number of misconceptions floating around which, as one of those 6% of males who are deuteranomalous, I do my best to clear up whenever possible.
Keyframe 16y ago
Yes, http://en.wikipedia.org/wiki/Chartreuse_(color)#Chartreuse_in_popular_culture http://en.wikipedia.org/wiki/Chartreuse_(color)#Chartreuse_i... Chartreuse would: Since about 1973, a sort of fluorescent chartreuse yellow has been adopted as the color of fire engines in parts of the United States and elsewhere. The reason behind this is that chartreuse fire engines are more visible on the streets than the traditional red fire engines, especially at night... However, everyone is conditioned to a semaphore scheme of GREEN go, RED stop, so I guess that can't be conditioned out.
- pbhjpbhj 16y ago
  Chartreuse is basically the fluorescent green colour of 80s (and now!) fashion. Strong fluorescent colours, particularly the pink, do terrible things to my eyes in some circumstances particularly when they have contrasting writing on them.

lincolnq 16y ago

Wow, I didn't know that roundabouts are more efficient than other intersection types. That's really cool. (Now I want to build a traffic simulator that can simulate that effect...)

rbritton 16y ago
There's a roundabout by my business that they put in about two years ago. There's also a large trucking hub that has to go through it to access the interstate. Whoever designed it didn't consider this factor when putting it in, so it's too small for a semi truck to make it through. They just drive over the center.
- pbhjpbhj 16y ago
  In the UK we often have smaller roundabouts, called "mini-roundabouts", they're designed with a small hump of circular horizontal cross-section that can easily be driven over by large vehicles. It's part of the design that trailer towing vehicles or wide vehicles can simply drive over the top if necessary.
JoeAltmaier 16y ago
Hm. We have one in town - 3 roads, 2 lanes, one of which doesn't go all the way around. A "map" posted 100 yards in front listing all the options. I've seen people stop to look at the map before going on. This is not more efficient.
- nitrogen 16y ago
  Take down the map and it probably would be. We had an intersection in my city with three roads/six entrances. Originally it was a 6-way stop, but it had very poor visibility and there were numerous accidents. Now, it's a roundabout, and traffic flows much more smoothly (I've never seen more than three cars waiting to enter, and it usually takes about 5-10 seconds per car). Multi-lane roundabouts are probably more confusing than single-lane, as well, but if the street is primarily traveled by locals, give them some time to learn it and speed should pick back up.

deleted 16y ago

[deleted]

lutorm 16y ago

The better stop sign would be no stop sign. The preponderance of stop signs on US roads is one of the most infuriating parts about American road engineering. (Along with such a large number of signs that it is not humanly possible to process them all when traveling at vehicle speeds.) It really does condition drivers to look for signs instead of other people. If you run a stop sign, you'll get fined even if nothing happens. If you stop at a stop sign and then in blissful ignorance ram someone who didn't, no harm comes to you (unlike to the other person). The book "Traffic" by Tom Vanderbilt is an interesting read about some counterintuitive things about how traffic works and about how differently engineers in different countries approach safety. I can highly recommend it. EDIT: One of the most fascinating stories in the book is about how they redesigned some big 5-way intersection with a traffic light in some central square of a Dutch city by just removing everything and leaving a big empty square with some lines painted indicating the roundabout. Crashes went down, and traffic flow improved, because drivers were forced to pay attention to figure out how the whole thing worked. Experience seems to indicate that the "safety" measures usually taken in the US (widening roads, removing pedestrians, etc) are totally counterproductive because they send subconscious signals to the drivers that this is a speedway which causes everyone to drive faster and pay less attention, which makes crashes more severe (not to mention relegates pedestrians, bicycles and other alternative means of transport to second-hand status.)

nkurz 16y ago
I don't disagree, but your phrasing seems odd considering that the linked article is written by the same Tom Vanderbilt who wrote "Traffic". This might imply that it already takes your points into consideration?
- lutorm 16y ago
  I'm not necessarily criticizing the article, just voicing my immediate comment on the topic in the title.
thrdOriginal 16y ago
Completely anecdotal: a friend of mine moved here (US) from Germany ~ 5 weeks ago, and she was driving my car with me in the passenger seat. Just as I was thinking "she is a safe defensive driver," she approached a stop sign and to my shock did not stop, but slowed down only to continue on her way much like a yield sign. I freaked out a little in the vein of "Stop signs here are not suggestions!" She responded with points simiar to yours (and the articles'): there are way too many stop signs in the US, it is the most expensive part of driving (fuel-wise), and it essentially teaches people not to be thoughtful, cautious drivers. Now while driving I'm constantly thinking "what a wasteful stop sign."

lukev 16y ago

When I drive I look as much for shape and color as the actual words. To sell me on the idea of a new stop sign, you'd have to demonstrate that not only was the new design objectively better, but it is objectively better by a large enough margin to offset all the additional errors caused by drivers who aren't trained to look for a different design.

JoeAltmaier 16y ago

Keep designing and we'll end up in a hole. Look at brake lights. First just two little lights. Then big, reflective lights. Then another light in the rear window. Then one on the mirror. Soon every car will look like the Vegas strip. Why all this inflation? Because we get lazy the more obvious the light becomes? How about one tiny bulb, that you have to really strain to see. Cheaper, keep us all "in the drivers seat" instead of making our way to work in a zombie state.

potatolicious 16y ago
The big, reflective lights are there partially due to the fact that we're using LEDs for brake lights instead of bulbs. The advantage here is that LEDs respond much faster than bulbs, which have a significant delay between power applied vs. light generated.