Is this Illegal?

[Amtrakprod]

There's a video I was watching the other day, two of the three flashing yellow arrow signals look to be against the MUTCD, what do you think, here's the link:

[seicer]

I don't get how these aren't already illegal. What if you are colorblind?

[hotdogPi]

I don't get how these aren't already illegal. What if you are colorblind?

For those that are colorblind, standard green and yellow can be determined by its position on the signal. This means that there's a problem if a flashing yellow arrow isn't where it would normally be (which is the case in this video), but it's definitely not true for all flashing yellow arrows.

[seicer]

That's what I was referring to - the position of the flashing yellow arrow.

[jeffandnicole]

The only people that never seem concerned about signals are those that ARE colorblind.  Everyone else just tries to assume they'll have issues with signals.

And I have to say, I can't recall a single accident where a news story came out that said someone couldn't figure out the signal due to their colorblindness.

[seicer]

I had to don on special googles that simulated color blindness for a QA project, and we went for a drive. It was very difficult to make out what those traffic signals were indicating (we could see color, but on grayscale - it would be very difficult to make a decision quickly).

How hard is it for the state or local DOT to actually follow the law? Or the ADA? Other states handle this quite well with a 5 lens setup.

[TheArkansasRoadgeek]

The only people that never seem concerned about signals are those that ARE colorblind.  Everyone else just tries to assume they'll have issues with signals.

And I have to say, I can't recall a single accident where a news story came out that said someone couldn't figure out the signal due to their colorblindness.

Exactly! There are a variety of color blindnesses.

What are the different types of color blindness?
The most common types of color blindness are inherited. They are the result of defects in the genes that contain the instructions for making the photopigments found in cones. Some defects alter the photopigment's sensitivity to color, for example, it might be slightly more sensitive to deeper red and less sensitive to green. Other defects can result in the total loss of a photopigment. Depending on the type of defect and the cone that is affected problems can arise with red, green, or blue color vision.

Red-Green Color Blindness
The most common types of hereditary color blindness are due to the loss or limited function of red cone (known as protan) or green cone (deutran) photopigments. This kind of color blindness is commonly referred to as red-green color blindness.

Protanomaly: In males with protanomaly, the red cone photopigment is abnormal. Red, orange, and yellow appear greener and colors are not as bright. This condition is mild and doesn't usually interfere with daily living. Protanomaly is an X-linked disorder estimated to affect 1 percent of males.
Protanopia: In males with protanopia, there are no working red cone cells. Red appears as black. Certain shades of orange, yellow, and green all appear as yellow. Protanopia is an X-linked disorder that is estimated to affect 1 percent of males.

Deuteranomaly: In males with deuteranomaly, the green cone photopigment is abnormal. Yellow and green appear redder and it is difficult to tell violet from blue. This condition is mild and doesn't interfere with daily living. Deuteranomaly is the most common form of color blindness and is an X-linked disorder affecting 5 percent of males.

Deuteranopia: In males with deuteranopia, there are no working green cone cells. They tend to see reds as brownish-yellow and greens as beige. Deuteranopia is an X-linked disorder that affects about 1 percent of males.
Blue-Yellow Color Blindness
Blue-yellow color blindness is rarer than red-green color blindness. Blue-cone (tritan) photopigments are either missing or have limited function.

Tritanomaly: People with tritanomaly have functionally limited blue cone cells. Blue appears greener and it can be difficult to tell yellow and red from pink. Tritanomaly is extremely rare. It is an autosomal dominant disorder affecting males and females equally.

Tritanopia: People with tritanopia, also known as blue-yellow color blindness, lack blue cone cells. Blue appears green and yellow appears violet or light grey. Tritanopia is an extremely rare autosomal recessive disorder affecting males and females equally.
Complete color blindness
People with complete color blindness (monochromacy) don't experience color at all and the clearness of their vision (visual acuity) may also be affected.

There are two types of monochromacy:

Cone monochromacy: This rare form of color blindness results from a failure of two of the three cone cell photopigments to work. There is red cone monochromacy, green cone monochromacy, and blue cone monochromacy. People with cone monochromacy have trouble distinguishing colors because the brain needs to compare the signals from different types of cones in order to see color. When only one type of cone works, this comparison isn't possible. People with blue cone monochromacy, may also have reduced visual acuity, near-sightedness, and uncontrollable eye movements, a condition known as nystagmus. Cone monochromacy is an autosomal recessive disorder.
Rod monochromacy

or

achromatopsia: This type of monochromacy is rare and is the most severe form of color blindness. It is present at birth. None of the cone cells have functional photopigments. Lacking all cone vision, people with rod monochromacy see the world in black, white, and gray. And since rods respond to dim light, people with rod monochromacy tend to be photophobic — very uncomfortable in bright environments. They also experience nystagmus. Rod monochromacy is an autosomal recessive disorder.

[seicer]

What type of color blindness is irrelevant if the position of the signals can't be judged. Similar to how there is an upside-down traffic signal somewhere in New York, it would be difficult or impossible for someone with a disability to correctly determine what the signal position is. Is it green for go? Yellow for caution? Or red for stop? Proper positioning, which is standardized around the world for a reason, is a necessity.

[TheArkansasRoadgeek]

What type of color blindness is irrelevant if the position of the signals can't be judged. Similar to how there is an upside-down traffic signal somewhere in New York, it would be difficult or impossible for someone with a disability to correctly determine what the signal position is. Is it green for go? Yellow for caution? Or red for stop? Proper positioning, which is standardized around the world for a reason, is a necessity.

True, but there are some [blindnesses] that hamper the ability to be confident in a certain color. Where read is a more purple color than red. I am not color blind, so hopefully this video will help.

https://www.youtube.com/watch?v=iNRQB5309yo

[kalvado]

What type of color blindness is irrelevant if the position of the signals can't be judged. Similar to how there is an upside-down traffic signal somewhere in New York, it would be difficult or impossible for someone with a disability to correctly determine what the signal position is. Is it green for go? Yellow for caution? Or red for stop? Proper positioning, which is standardized around the world for a reason, is a necessity.

Type of color blondness is quite relevant if traffic light have proper colors. Older traffic lights had pretty bad green, newer have green partially going into blue - I assume appeal to RG cone problems are part of it.

[kalvado]

What type of color blindness is irrelevant if the position of the signals can't be judged. Similar to how there is an upside-down traffic signal somewhere in New York, it would be difficult or impossible for someone with a disability to correctly determine what the signal position is. Is it green for go? Yellow for caution? Or red for stop? Proper positioning, which is standardized around the world for a reason, is a necessity.

True, but there are some [blindnesses] that hamper the ability to be confident in a certain color. Where read is a more purple color than red. I am not color blind, so hopefully this video will help.

https://www.youtube.com/watch?v=iNRQB5309yo

OK, lets talk types of color vision details. We need confusion between yellow and green for this to become a problem

Which types are you referring to?

[jeffandnicole]

What type of color blindness is irrelevant if the position of the signals can't be judged. Similar to how there is an upside-down traffic signal somewhere in New York, it would be difficult or impossible for someone with a disability to correctly determine what the signal position is. Is it green for go? Yellow for caution? Or red for stop? Proper positioning, which is standardized around the world for a reason, is a necessity.

Rather than talking on behalf for others, just give us examples of where colorblindness and illegal traffic lights lead to accidents and crashes.

[seicer]

Don't be obtuse: no citations are needed for what's obvious. For all that people obsess over particulars in certain fonts, it's kosher to have upside-down traffic signals? To have green/yellow lights in one lens? This is a federal ADA issue, and we have these uniform standards for a reason. And while it affects a minority, it's still a relevant talking point. We build ADA accessible ramps for the disabled; why can't we extend that to those that may experience an eyesight deficiency?

To clarify in a previous comment: I wasn't meaning to remark on the types of blindness. In our QA setup, we could see color and when we approached a traffic light, we had to reference our guide as to what color in our goggles matched red (stop), yellow (caution) and green (go). Of course, when you have a yellow/green flashing arrow combination, you could perceive that difference, but it's still not an ideal situation.

But what happens when the colors are grayscale? I actually thought that this shape-oriented traffic signal was a decent compromise: https://jalopnik.com/5559908/uni-signal-a-traffic-light-for-the-color-blind-and-everyone-else

[kalvado]

Don't be obtuse: no citations are needed for what's obvious. For all that people obsess over particulars in certain fonts, it's kosher to have upside-down traffic signals? To have green/yellow lights in one lens? This is a federal ADA issue, and we have these uniform standards for a reason. And while it affects a minority, it's still a relevant talking point. We build ADA accessible ramps for the disabled; why can't we extend that to those that may experience an eyesight deficiency?

To clarify in a previous comment: I wasn't meaning to remark on the types of blindness. In our QA setup, we could see color and when we approached a traffic light, we had to reference our guide as to what color in our goggles matched red (stop), yellow (caution) and green (go). Of course, when you have a yellow/green flashing arrow combination, you could perceive that difference, but it's still not an ideal situation.

But what happens when the colors are grayscale? I actually thought that this shape-oriented traffic signal was a decent compromise: https://jalopnik.com/5559908/uni-signal-a-traffic-light-for-the-color-blind-and-everyone-else

Grayscale color blindness rate is about 1 case in a million people, usually accompanied with other vision problems. It is really about return of investment issue - especially that there are many others, more common medical conditions  which lead to denial of license.

[jeffandnicole]

...To have green/yellow lights in one lens? This is a federal ADA issue, and we have these uniform standards for a reason...

NJ has used green/yellow arrows in one lens for at least 30 years; they were probably one of the first states to do so.  There's been a lot of ADA complains about curb access, ped push buttons, etc, in the state, but not once can I recall anyone complaining about the bi-model arrows.

So no, it's not an ADA issue.  People you believe would be affected by it aren't, so no need creating an issue where none exists.

[seicer]

I'm surprised it isn't but it may because the rate of greyscale colorblindness is so low (something I wasn't aware of). And I wasn't aware that the combination color lenses was so commonplace - having come from a state that had doghouses and now 5-stack signal units.

[kalvado]

I'm surprised it isn't but it may because the rate of greyscale colorblindness is so low (something I wasn't aware of). And I wasn't aware that the combination color lenses was so commonplace - having come from a state that had doghouses and now 5-stack signal units.

I looked around - and, interestingly enough, the main concern for color blind people seems to be seeing taillights of cars in the dark.
Blue cone in intact in most cases - and standard for green light is such that there is some blue in there, so green is not confused with anything else in most color blind people. And that is the most dangerous confusion, apparently...

[TheArkansasRoadgeek]

Don't be obtuse: no citations are needed for what's obvious. For all that people obsess over particulars in certain fonts, it's kosher to have upside-down traffic signals? To have green/yellow lights in one lens? This is a federal ADA issue, and we have these uniform standards for a reason. And while it affects a minority, it's still a relevant talking point. We build ADA accessible ramps for the disabled; why can't we extend that to those that may experience an eyesight deficiency?

To clarify in a previous comment: I wasn't meaning to remark on the types of blindness. In our QA setup, we could see color and when we approached a traffic light, we had to reference our guide as to what color in our goggles matched red (stop), yellow (caution) and green (go). Of course, when you have a yellow/green flashing arrow combination, you could perceive that difference, but it's still not an ideal situation.

But what happens when the colors are grayscale? I actually thought that this shape-oriented traffic signal was a decent compromise: https://jalopnik.com/5559908/uni-signal-a-traffic-light-for-the-color-blind-and-everyone-else

Grayscale color blindness rate is about 1 case in a million people, usually accompanied with other vision problems. It is really about return of investment issue - especially that there are many others, more common medical conditions  which lead to denial of license.

They make color blindness [EnChroma] [assistance] glasses, but the glasses attempt to correct a loss in the spectrum of color, so I am not sure if it would fix grayscale blindness (achromatopsia).

[kalvado]

They make color blindness [EnChroma] [assistance] glasses, but the glasses attempt to correct a loss in the spectrum of color, so I am not sure if it would fix grayscale blindness (achromatopsia).

Of course not. Glasses may correct situation if one of pigments mutated too far (some shift is a version of norm, red pigment is split between 4 versions in general population as 50/40/(10 for two) - and I believe 4th version is the "red weak" color blindness). But that means glasses can work for 2/3 of those with color vision issues.

[Duke87]

But what happens when the colors are grayscale? I actually thought that this shape-oriented traffic signal was a decent compromise: https://jalopnik.com/5559908/uni-signal-a-traffic-light-for-the-color-blind-and-everyone-else

Quebec had their own version of this concept as standard issue for a while, with square reds and diamond yellows. Here's an example.

They discontinued these, though, after determining that they provided no measurable benefit to colorblind drivers over standard signals. And because having the lights be different shapes complicates maintenance.

[Revive 755]

Going back to the original post, I don't think the overhead signal complies with the national MUTCD.  The national MUTCD does not appear to allow a green arrow to be positioned horizontally next to a flashing yellow arrow except in a doghouse for a shared left turn/right turn lane as shown in Figure 4D-20, Part B and as mentioned in 4D.25 Paragraph 06 Item B.  To be sure of MUTCD compliance while only using three vertical sections the overhead signal would need to use a bimodal green arrow/flashing yellow arrow.  A bimodal flashing yellow arrow/steady yellow arrow 3-section per Interim Approval 17 head could also be used, but I am not sure it would be a good idea to mix this with the adjacent four section FYA head.

[Amtrakprod]

Going back to the original post, I don't think the overhead signal complies with the national MUTCD.  The national MUTCD does not appear to allow a green arrow to be positioned horizontally next to a flashing yellow arrow except in a doghouse for a shared left turn/right turn lane as shown in Figure 4D-20, Part B and as mentioned in 4D.25 Paragraph 06 Item B.  To be sure of MUTCD compliance while only using three vertical sections the overhead signal would need to use a bimodal green arrow/flashing yellow arrow.  A bimodal flashing yellow arrow/steady yellow arrow 3-section per Interim Approval 17 head could also be used, but I am not sure it would be a good idea to mix this with the adjacent four section FYA head.

Thank you, that's what I was wondering about.