MUTCD Notice of Proposed Rulemaking (2020) now available

[NoGoodNamesAvailable]

Okay, so the new standard is that overhead exit direction signs have the diagonal arrow to the right (or the left) of the legend, while post-mounted signs have it centered below the legend.

Can anyone explain to me why this is a standard or what the rationale may be?

I don't understand the requirement here for post-mounted BGS. Results in a larger sign panel for no legibility benefit that I can see.

[jakeroot]

One thing on my wish list is for shared lane left turn signals flashing yellow arrow doghouses could be allowed. That would be really nice to see!

It seems that they are sort of going to allow it as a result of "Interpretation Letter 4(09)-15 (I)", but only for approaches without through movements (see new section 4F.16 and figure 4F.15), approaches with a shared through and right turn lane (see new section 4F.09), and double left turns where there is a shared left and straight lane (see new section 4F.02). I can't find anything about permitting them in general for shared left turn lane approaches.

I find this a bit strange, as that interpretation above seems to have originated as a request to allow approaches without dedicated left turn lanes to operate with protected/permissive phasing using a 5-section signal and bi-modal green arrow/flashing yellow arrow signal face. It would seem this is the only thing the new MUTCD doesn't clearly mark out as being permitted when it comes to shared signal faces with flashing yellow arrows.

[odditude]

Okay, so the new standard is that overhead exit direction signs have the diagonal arrow to the right (or the left) of the legend, while post-mounted signs have it centered below the legend.

Can anyone explain to me why this is a standard or what the rationale may be?

I don't understand the requirement here for post-mounted BGS. Results in a larger sign panel for no legibility benefit that I can see.

maybe to reduce the need for brush clearing via narrower signage?

[Scott5114]

If you have brush that close to the signage then your clear zone probably isn't wide enough.

[Revive 755]

EDIT: I cannot find that change request. Anyone know where it is? Did they misidentify it?

This one?

[jakeroot]

EDIT: I cannot find that change request. Anyone know where it is? Did they misidentify it?

This one?

That's it, thank you. Any idea what "receipt acknowledged" might mean? I'm trying to find information about this change request but I'm coming up empty-handed.

[Scott5114]

I imagine that FHWA merely acknowledges that it received the request, with no particular implication as to whether it was accepted or rejected.

[jakeroot]

I imagine that FHWA merely acknowledges that it received the request, with no particular implication as to whether it was accepted or rejected.

But as I highlighted in my post on the last page, it was definitely accepted. It is referenced three times in the 2020 MUTCD...this is one of the sections where it is referenced:

E. During steady mode (stop-and-go) operation, the signal section that displays the steady left-turn YELLOW ARROW signal indication during change intervals shall not be used to display the flashing left-turn YELLOW ARROW signal indication for permissive left turns unless a signal section capable of alternating between the display of a steady YELLOW ARROW and a flashing YELLOW ARROW signal indication is used. Added to reflect Official Change Request 4(09)-42

[Dirt Roads]

I have a strong dislike of multiple uses for the same section like solid/flashing and green/yellow bimodal. The transition between different sections helps draw attention that something has changed, and the shape of the signal also conveys information about what type of indications I can expect out of the signal. When you start reusing section, it shatters this.

If the intent really is for cost savings to facilitate conversions, at least restrict this usage to retrofits of existing signals and require that new/redone installations be done with a 4-section head.

Fully agreed. Plus some parts of the country already have 3-section FYAs where the flashing yellow is in the bottom position either on its own or as a bimodal. I'm not liking the potential inconsistency here.

I can understand both points, but I think the way the MUTCD has approached it makes sense. Retrofits are easier when you can simply replace the computers that would then allow the signal head to flash. If I understand correctly, no signal head replacements should be necessary. If this is the idea, then eliminating the option to allow a bi-modal flashing yellow/green arrow should be the obvious next step to begin normalizing the position of the flashing yellow arrow within 3-section FYA signals. Given that there are arguments in favor of both 3-section setups: all things being equal, we should just work towards normalizing the position.

<snipped>

I'm with Bitmapped on this one.  On the railroad, FRA regulations require that any failure mode in the signal head that could cause [confusion] needs to be detected and the signal aspect must be adjusted accordingly.  That doesn't perfectly fit with this issue, but it gives you a sense of where I'm coming from.  The issues with color-blind folks are obvious, but there's also some concern that a failed yellow flasher showing solid in the wrong position can really cause some confusion (particularly in parts of the country where yellow means "hurry up before it turns red").

[NoGoodNamesAvailable]

It looks like the FHWA made a pretty big typo in chapter 9A, accidentally deleting the phrase "shall not" in the introductory language:

The absence of a marked bicycle lane or any of the other traffic control devices discussed in this Chapter on a particular roadway [shall not] mean that bicyclists are not permitted to travel on that roadway.

Oops! People caught on assuming that the change was deliberate and left some pretty severe comments on the docket! FHWA left a note on their news feed that the change was accidental and fixed the issue.

[Dustin DeWinn]

It states that the Light Blue Chromacity Coordinates are yet to be determined.

Is this something still being researched or yet to be researched?

[kalvado]

It states that the Light Blue Chromacity Coordinates are yet to be determined.

Is this something still being researched or yet to be researched?

You know, this question got me thinking... And looks like this is pretty involved.
Few organizations, including FHWA, FAA and SAE have their definition for standard colors. COlors unually defined are black and white; red, green, blue; usually orange and yellow. FHWA also has Flourescent Yellow-Green, Flourescent Pink, and  Brown and Purple. I don't see definitions for light blue, purple, or cyan (which may be another important one)
However, it looks like combining those colors with text may be an issue preventing simply defining colors. 

Human vision is RGB, with R and G strongly evolving for the sake of survival - that is, to see the color of fruit to determine if it is ripe or not. Blue is a later evolutionary addition; there are few blues with survival implications.

This RGB pattern is strikingly obvious in signage. Black and white, or 0 primary colors vs 3, is the highest contrast.
Next step is 1 vs 3 - and those would be white vs red, green, or blue. And those are most common colored sign combinations.
Another one is 0 vs 2 channels - black on orange and yellow.
Looks like those would be the best color schemes available.

Two others are brown/white and purple/white.
Brown is a low intensity yellow or orange, and can be confused with those in uneven illumination. A common trick to prove that is to look at a brown object through a tube, such as a rolled magazine. Yet, a half intensity yellow/orange vs black provides 1 vs 3 contrast for less important signs.
Highly saturated (e.g. low reflection intensity) red+blue = purple vs white is the other example of same logic.

That brings me to question what is "light blue". If it is cyan, e.g. combination of green and blue, it may be used with blackk, but it looks low contrast to me. Whitish blue with black is another possible combo, again less than great.

Overall, here are some of the examples - random find on the internet - and I don't see any great examples besides pure dark blue. Probably the research is about just proving this...

[jeffandnicole]

I have a strong dislike of multiple uses for the same section like solid/flashing and green/yellow bimodal. The transition between different sections helps draw attention that something has changed, and the shape of the signal also conveys information about what type of indications I can expect out of the signal. When you start reusing sections, it shatters this.

New Jersey, for example, has long used 4 section heads with a bimodal G/Y arrow at the bottom (they can be found in horizontal lights as well).  I would estimate they have been in use for roughly 30 years, starting as fiber optics to change from green to yellow, then LEDs. 

I don't think there's been a single, official, declaration saying that there is any issue among the traveling public regarding these lights in that timespan.  And at least within the state, not that I claim to talk to everyone, but I've never heard anyone have a complaint about this.  We hear complains all the time about the jughandles and how you have to make a right turn turn left or make a u-turn, but the bi-modal arrow appears to garner no complains and is easy to understand.

... then eliminating the option to allow a bi-modal flashing yellow/green arrow should be the obvious next step to begin normalizing the position of the flashing yellow arrow within 3-section FYA signals. Given that there are arguments in favor of both 3-section setups: all things being equal, we should just work towards normalizing the position.

The issue I have with this is something like the bi-modal arrow has been around for decades, the flashing yellow has been around for a decade. A 4 section light with 2 Reds at the top has been around even longer.  Because various intersections can have unique features, there is a degree of variability that should be considered.  Since the MUTCD already accounts for these options within the placement of the lights in a tower, there shouldn't be any need to further restrict to to a non-optional standard that doesn't necessary work with all types of approved signal options.

The issues with color-blind folks are obvious...

I have long maintained that the only people having a problem with color-blindness when it comes to bi-modal arrows are those who are not color-blind.  There has never been anything to suggest that color-blind drivers have an issue with these signals.

It's the equivalent of an able-bodied person telling someone in a wheelchair "I know how you feel".  No, you don't.

[Dirt Roads]

The issues with color-blind folks are obvious...

I have long maintained that the only people having a problem with color-blindness when it comes to bi-modal arrows are those who are not color-blind.  There has never been anything to suggest that color-blind drivers have an issue with these signals.

It's the equivalent of an able-bodied person telling someone in a wheelchair "I know how you feel".  No, you don't.

I presume that the green arrow is never extended in a flash mode.  Therefore, my main concern is that a truly color-blind person cannot tell the difference between a solid green arrow and a yellow arrow that is failing to flash.  I've tested enough traffic signal equipment to have witnessed several types of failures that caused flashing signals not to flash (as well as causing non-flashing signals to flash, but at a rate associated with the power frequency).  Fortunately, none of these signals ever had bi-modal lenses.

Although I am able to tell the difference between green and yellow, I am sufficiently color-blind that I must recuse myself from visual certification of signal aspects on railroads that do not utilize color-position.  My home road (the Chesapeake and Ohio) used a quirky system where the red lens in the lower signal heads were placed at different locations to create the maximum separation between the red lenses on each head.  In later years, I would have needed to quit that job once the standard green-over-yellow-over-red became intermixed with the juggled ones.

All that being said, I have a friend who is fully color-blind and I can't fathom what that is like.  I can still dress myself with a stylish tie, shirt and jacket combination in a number of earth tones even when I can't tell what color they are.

[Pink Jazz]

The issues with color-blind folks are obvious...

I have long maintained that the only people having a problem with color-blindness when it comes to bi-modal arrows are those who are not color-blind.  There has never been anything to suggest that color-blind drivers have an issue with these signals.

It's the equivalent of an able-bodied person telling someone in a wheelchair "I know how you feel".  No, you don't.

I presume that the green arrow is never extended in a flash mode.  Therefore, my main concern is that a truly color-blind person cannot tell the difference between a solid green arrow and a yellow arrow that is failing to flash.  I've tested enough traffic signal equipment to have witnessed several types of failures that caused flashing signals not to flash (as well as causing non-flashing signals to flash, but at a rate associated with the power frequency).  Fortunately, none of these signals ever had bi-modal lenses.

Although I am able to tell the difference between green and yellow, I am sufficiently color-blind that I must recuse myself from visual certification of signal aspects on railroads that do not utilize color-position.  My home road (the Chesapeake and Ohio) used a quirky system where the red lens in the lower signal heads were placed at different locations to create the maximum separation between the red lenses on each head.  In later years, I would have needed to quit that job once the standard green-over-yellow-over-red became intermixed with the juggled ones.

All that being said, I have a friend who is fully color-blind and I can't fathom what that is like.  I can still dress myself with a stylish tie, shirt and jacket combination in a number of earth tones even when I can't tell what color they are.

I do know that in the past the red and yellow signals had orange in their hue and the green signal had blue in its hue to aid colorblind users, however, I am not sure if that is still the case with LED signals, since LEDs are nearly (though not perfectly) monochromatic.

[kalvado]

The issues with color-blind folks are obvious...

I have long maintained that the only people having a problem with color-blindness when it comes to bi-modal arrows are those who are not color-blind.  There has never been anything to suggest that color-blind drivers have an issue with these signals.

It's the equivalent of an able-bodied person telling someone in a wheelchair "I know how you feel".  No, you don't.

I presume that the green arrow is never extended in a flash mode.  Therefore, my main concern is that a truly color-blind person cannot tell the difference between a solid green arrow and a yellow arrow that is failing to flash.  I've tested enough traffic signal equipment to have witnessed several types of failures that caused flashing signals not to flash (as well as causing non-flashing signals to flash, but at a rate associated with the power frequency).  Fortunately, none of these signals ever had bi-modal lenses.

Although I am able to tell the difference between green and yellow, I am sufficiently color-blind that I must recuse myself from visual certification of signal aspects on railroads that do not utilize color-position.  My home road (the Chesapeake and Ohio) used a quirky system where the red lens in the lower signal heads were placed at different locations to create the maximum separation between the red lenses on each head.  In later years, I would have needed to quit that job once the standard green-over-yellow-over-red became intermixed with the juggled ones.

All that being said, I have a friend who is fully color-blind and I can't fathom what that is like.  I can still dress myself with a stylish tie, shirt and jacket combination in a number of earth tones even when I can't tell what color they are.

I do know that in the past the red and yellow signals had orange in their hue and the green signal had blue in its hue to aid colorblind users, however, I am not sure if that is still the case with LED signals, since LEDs are nearly (though not perfectly) monochromatic.

My impression was that green definition became much deeper green to blue with the introduction of LEDs. Development wise, cyan-ish LEDs were developed first, purer green came much later.
ANd a random picture with "old" and "new" definition of green (no date, I suspect late 90's - early 00's)
As a matter of fact, the early definition was even more yellowish to allow for mostly yellow incandescent lights. There was a location over here with LED and incandescent lights located nearby; old style green was almost the same as LED yellow..

[RobbieL2415]

Didn't see it mentioned here, but the first few pages make it clear that Metric units will no longer be allowed in the Manual.

[Ned Weasel]

Didn't see it mentioned here, but the first few pages make it clear that Metric units will no longer be allowed in the Manual.

[TXtoNJ]

Didn't see it mentioned here, but the first few pages make it clear that Metric units will no longer be allowed in the Manual.

Absolutely ridiculous

[jakeroot]

... then eliminating the option to allow a bi-modal flashing yellow/green arrow should be the obvious next step to begin normalizing the position of the flashing yellow arrow within 3-section FYA signals. Given that there are arguments in favor of both 3-section setups: all things being equal, we should just work towards normalizing the position.

The issue I have with this is something like the bi-modal arrow has been around for decades, the flashing yellow has been around for a decade. A 4 section light with 2 Reds at the top has been around even longer.  Because various intersections can have unique features, there is a degree of variability that should be considered.  Since the MUTCD already accounts for these options within the placement of the lights in a tower, there shouldn't be any need to further restrict to to a non-optional standard that doesn't necessary work with all types of approved signal options.\

I would like to think the plan is to say "if you have a three-section signal that will include a flashing yellow arrow, the flashing yellow arrow should occupy the same lens as the solid yellow arrow, apart from these circumstances". I don't think the plan is to totally forbid bi-modal green/flashing yellow arrows.

In an ideal world, I don't think the flashing yellow arrow should occupy the solid yellow arrow lens. This may be contrary to what I've said earlier, but I think I prefer it to always occupy the third lens. This means that whether you're looking at a fully permissive FYA, a three section protected/permissive FYA, or a four section protected/permissive FYA, the flashing yellow arrow would always be third from the top. Not to mention that, yes, bi-modal signals are quite common already and there doesn't seem to be any issues with them. Although I think you'll find that they are not considered 'ideal' by most agencies.

Here in Pierce County, WA, along with several other local jurisdictions, the solid yellow and flashing yellow arrows occupy the same position. I don't know why this was done. To be fair to both, none have any four section FYA signals (although Pierce County replaced a few four section FYA signals with three section FYA signals...not sure why, although I guess things are more consistent now).

It's the equivalent of an able-bodied person telling someone in a wheelchair "I know how you feel".  No, you don't.

Not saying I agree or disagree, but couldn't the entire ADA be summed up with "I know how you feel"?

Taking reasonable steps to improve accessibility for all road users is, well, pretty reasonable. I, for one, think horizontal signals should only be used as necessary. I believe horizontal signals are considered to be a menace for those with yellow-green colorblindness and who are not used to seeing them. My cousin struggled big time when he moved from California to Texas.

[Scott5114]

Not saying I agree or disagree, but couldn't the entire ADA be summed up with "I know how you feel"?

I don't think so. ADA mandates accessibility requirements that have changed things for disabled people in meaningful ways. Like not allowing the only entrance to a business to be up a flight of stairs, or through a doorway that isn't wide enough to fit a standard wheelchair. It's kind of hard for people our age to imagine, since we've lived most of our lives in a post-ADA world, and thus don't have to interact with much pre-ADA architecture, but the US of the 1980s was a much more difficult place for a disabled person to navigate, just on a physical level.

ADA helps in other ways, too. My wife is disabled in a few different ways, and the ADA has been an invaluable shield against managers who have no clue how to handle a disabled employee and thus make unreasonable demands of her.

Taking reasonable steps to improve accessibility for all road users is, well, pretty reasonable. I, for one, think horizontal signals should only be used as necessary. I believe horizontal signals are considered to be a menace for those with yellow-green colorblindness and who are not used to seeing them. My cousin struggled big time when he moved from California to Texas.

This is a thing I've harped on and on about regarding Oklahoma City's Project 180 streetscaping initiative. In an ill-advised attempt at placemaking, all of the street hardware in the CBD has been replaced with some in a style that is distinct from that of the rest of the city (including the adjoining Bricktown tourism and recreation district). The Project 180-style traffic signal is horizontal, while the signals used in the rest of the city are vertical. So if you're going down a particular street that crosses into the P180 area (say, Reno Avenue), you'll see a bunch of vertical signals, then get a dozen or so intersections with horizontal signals, then suddenly everything goes back to vertical.

Try to bring up why this is a bad idea and you'll get drowned out by New Urbanists spouting an endless loop of "cool placemaking!"

[US 89]

Nah, I like OKC's downtown horizontal signals. They give it character.

On the other hand, surely they could have come up with something better for the street blades...

[Scott5114]

Nah, I like OKC's downtown horizontal signals. They give it character.

I think you mean

"cool placemaking!"

This is the exact problem I am describing–"giving it character" should not take precedence over "hey, it might make it difficult for some drivers to have the traffic signals jumping between vertical and horizontal as they traverse different parts of the same city".

At least if you move to a state or city that uses horizontal signals exclusively, you can become accustomed to them. If you're a colorblind driver that lives on, say, Northwest Expressway, and works on Memorial, and then have to go downtown for an errand like jury duty, and are suddenly confronted with signals that are put up at right angles to every other signal you've ever seen in this city, while being behind the wheel and dealing with all of the stresses of driving in a dense urban environment...

But hey, cool placemaking!

[corco]

This is the exact problem I am describing–"giving it character" should not take precedence over "hey, it might make it difficult for some drivers to have the traffic signals jumping between vertical and horizontal as they traverse different parts of the same city".

I assume this has been the case for a while - is there any evidence that this is actually a problem and has led to crashes, or is this a perceived problem that doesn't actually need to be solved?

[Scott5114]

It's fairly recent–I've found documents on the city website that suggest construction began November 2010, but I also know that it's been delayed several times and the project has been rather drawn out compared to the schedule. Over the period 2010—2020, there have been a number of major changes to the area that are wholly unrelated to Project 180, such as the realignment of I-40 and its replacement with an at-grade boulevard, construction of a major park and convention center, and a dizzying array of oil industry machinations that have led to spikes and troughs in office space occupancy, so I feel like any analysis of crash data would be inconclusive at best due to the changes in traffic patterns.

That being said, since this is presumably meant to be an artistic project–a reasonable assumption given that it is described in the design document as a "contemporary | minimalist | elegant | stainless steel | rectangular pole"–why must an artistic vision be pursued for Project 180 that affects safety-sensitive equipment? Since it is art, and art is subjective, selecting any individual aesthetic choice is essentially arbitrary–why not come up with a contemporary | minimalist | elegant | stainless steel | rectangular pole with vertical signal heads?

For comparison, Norman also did some placemaking in its downtown area around the same time, but that consisted of installing fancier mastarms with ornamental bases at ground level. The signal heads are identical to those used in the rest of the city.