Traffic signal

[thenetwork]

Basically, studies have shown that overhead signals are superior because they're harder to block.

It still absolutely boggles my mind that both overhead and side-mounted signals, together, aren't a requirement. There are certainly scenarios where I think side-mount only works just fine, but overhead signals can easily be blocked by a tall vehicle. The MUTCD really needs to re-work the signals section to require both overhead and side-mounted signals. It just makes sense.

I think it varies by state.  Here In Colorado, most major and secondary intersections will have overhead and side mounted (right side, left side or both sides).  Not as often at minor intersections, or on side streets at larger intersectiins (the main road will have them, though). 

Definitely helpful when you are stopped at an Intersection and can't see the overheads due to the vehicles in front of you. Also helpful if you.are driving right into the sunlight, side mounted lights are a great way to see the signal without having to position your hands to block the sun.

[roadman65]

Roadman65, where does the MUTCD say that side-mounts are not permitted?

Not exactly  not permitted, but solely no. 

Technically incorrect. The guidance is that pole-mounted signals should not be used by themselves. Guidance here is a number of overhead signals equal to the number of lanes minus 1, with a minimum of 1. MUTCD recommends having ALL primary faces overhead, with only supplementals pole-mounted. Primary faces governing turn movements should be always be overhead. See Table 4D-1 and the surrounding section. Basically, studies have shown that overhead signals are superior because they're harder to block.

I am for having both, but if a place already has them and they work fine than why fix what is not broken.  It is what it is though unfortunately.

[TheArkansasRoadgeek]

Its against the MUTCD to not have a stop sign installed with a flashing red beacon.  Even in the NJ Shore back when the cities there were only summer time resorts, STOP signs had to be erected when signals were in flash mode from September to May and even in Kissimmee where three stop lights are permanently flashing.  The red flasher on the signals cannot be sole traffic control device.

Hahaha,you're funny! Arkansas does it all the time it seems. Either that or they don't replace the stop sign! I saw an intersection on a stretch of state highway that had a beacon, but no stop. Come to think of it, I have seen several setups like that in the state.

[jakeroot]

Basically, studies have shown that overhead signals are superior because they're harder to block.

It still absolutely boggles my mind that both overhead and side-mounted signals, together, aren't a requirement. There are certainly scenarios where I think side-mount only works just fine, but overhead signals can easily be blocked by a tall vehicle. The MUTCD really needs to re-work the signals section to require both overhead and side-mounted signals. It just makes sense.

I think it varies by state.  Here In Colorado, most major and secondary intersections will have overhead and side mounted (right side, left side or both sides).  Not as often at minor intersections, or on side streets at larger intersectiins (the main road will have them, though). 

Definitely helpful when you are stopped at an Intersection and can't see the overheads due to the vehicles in front of you. Also helpful if you.are driving right into the sunlight, side mounted lights are a great way to see the signal without having to position your hands to block the sun.

Oh, no I understand that. Colorado has excellent signal-placement standards. As does California, Wisconsin, Minnesota, Nevada, Arizona, and Illinois, amongst several other places.

My issue is that these states are technically going "above and beyond" the MUTCD. I'm not even sure what the MUTCD says on secondary signals, but it's definitely only a recommendation, and not a requirement. The only requirement is that two heads are provided for the through movement. That is not sufficient at all, and you end up getting a lot of really closely spaced signals like those I posted three pages back.

[SignBridge]

If you read the Manual carefully, it does not specify either overhead or pole mounted heads. Sec. 4D.13 addresses lateral placement of required heads. At least one and preferably both (only one actually reqd.) heads must be in the driver's so called "cone-of-vision". See Figure 4D-4. If that requirement can be met with post/pole mounted heads, it is acceptable under the standard.

However, Sec. 4D.11.06 (Support) recommends one overhead signal-face per lane on the far side of the intersection (as compared to diagonal span). But that is only a strong suggestion, not a standard.

[roadman65]

One thing that annoys me is you get behind a truck in FL and being our signal heads are paired so close together you cannot see them.


NJ had them in many places on the sides and almost always one over the opposing traffic lane. NYC does too. So you will see around any semi or small truck.

[TheArkansasRoadgeek]

If you read the Manual carefully, it does not specify either overhead or pole mounted heads. Sec. 4D.13 addresses lateral placement of required heads. At least one and preferably both (only one actually reqd.) heads must be in the driver's so called "cone-of-vision". See Figure 4D-4. If that requirement can be met with post/pole mounted heads, it is acceptable under the standard.

However, Sec. 4D.11.06 (Support) recommends one overhead signal-face per lane on the far side of the intersection (as compared to diagonal span). But that is only a strong suggestion, not a standard.

I always wonder whether a DOT sits down to read the MUTCD or if it is like any other ToS Agreements out there (i.e. skimmed and agreed to or not read at all and agreed to it anyway).

[Revive 755]

I always wonder whether a DOT sits down to read the MUTCD or if it is like any other ToS Agreements out there (i.e. skimmed and agreed to or not read at all and agreed to it anyway).

It seems to depend vary on the particular DOT - some of them seem to since they take the national MUTCD and adapt it into a state version. 

Generally though I think most of the DOT's try to follow all of the should statements as well as the shall statements due to liability concerns.

[SignBridge]

Roadman65, you're right about New Jersey. Almost all signalized intersections there have either the second required head, or a 3rd head on the near side over the opposing lane on the back of the mast-arm for the opposing direction. Very smart on their part. Eliminates the problem of being behind a large truck blocking the view of both closely spaced heads.

[TheArkansasRoadgeek]

Roadman65, you're right about New Jersey. Almost all signalized intersections there have either the second required head, or a 3rd head on the near side over the opposing lane on the back of the mast-arm for the opposing direction. Very smart on their part. Eliminates the problem of being behind a large truck blocking the view of both closely spaced heads.

As far as I have seen, Little Rock is the only city with such a signal setup in Arkansas.

[US 89]

Another weird Utah signal I have seen is this one.

Basically, it's a four-section head with red ball, red right arrow, yellow ball, green ball. The two red indications are only ever on at the same time, and it seems to emphasize that there is no right turn on red at this intersection because it's a CFI. It was a bit odd when I saw it at first, because it was a four section head with one green ball at the bottom.

This setup is installed at several of the CFI's along Bangerter. Has anyone seen this anywhere else, and is it allowed by the MUTCD? Wouldn't a setup with only right arrows be better, as the left turns here are already protected only?

[TheArkansasRoadgeek]

This setup is installed at several of the CFI's along Bangerter. Has anyone seen this anywhere else, and is it allowed by the MUTCD? Wouldn't a setup with only right arrows be better, as the left turns here are already protected only?

Remember: The MUTCD is merely guidelines for how an intersection or other TCD should be configured and is not necessarily a requirement.

I personally have not seen this signal type in my state. We use the MUTCD, but we have policies that allow for flexibility (in that case I don't know why Arkansas doesn't use it's own).

[jakeroot]

Has anyone seen this anywhere else, and is it allowed by the MUTCD? Wouldn't a setup with only right arrows be better, as the left turns here are already protected only?

Seems rather pointless. The extra signal reminds me of this signal near my home. I don't see the reason why a three-head arrow couldn't have been used here. Right-on-red is still allowed with red arrows in Washington:

https://www.youtube.com/watch?v=bLg9ZOZIWx4

[US 89]

Has anyone seen this anywhere else, and is it allowed by the MUTCD? Wouldn't a setup with only right arrows be better, as the left turns here are already protected only?

Seems rather pointless. The extra signal reminds me of this signal near my home. I don't see the reason why a three-head arrow couldn't have been used here. Right-on-red is still allowed with red arrows in Washington:

https://www.youtube.com/watch?v=bLg9ZOZIWx4

Right-on-red is not allowed on red arrows in UT. To add to the overkill, there is an electronic no right turn sign which turns off when the light is green/yellow. Seems like a waste when you could just put a "no turn on red" sign there, which is usually what is done at intersections where RTOR isn't allowed.

The reason right-on-red isn't allowed here is because this is a CFI, and a right on red here would conflict with the left turn movement from northbound Bangerter to 5400 S westbound, and the same goes for the opposite side.

If right turn is allowed on red, they will use a 3-head signal with a red ball and yellow/green arrows.

[jakeroot]

Right-on-red is not allowed on red arrows in UT. To add to the overkill, there is an electronic no right turn sign which turns off when the light is green/yellow. Seems like a waste when you could just put a "no turn on red" sign there, which is usually what is done at intersections where RTOR isn't allowed.

There is a similar electronic "No turn on red" sign in Seattle, which is only displayed when the perpendicular crosswalk has a walk sign. Unlike the Bangerter example (where turning on red would require you to cross an entire carriageway before yielding to traffic from the left), this intersection could allow right turn on red because it's just a normal intersection. RTOR is only disallowed to prevent pedestrian conflicts.

The left turn signal should definitely just be a three-head arrow signal. I see no reason to use the four-head, red ball/red arrow setup. Seems to just be emphasis, at best.

[Revive 755]

Another weird Utah signal I have seen is this one.

Basically, it's a four-section head with red ball, red right arrow, yellow ball, green ball. The two red indications are only ever on at the same time, and it seems to emphasize that there is no right turn on red at this intersection because it's a CFI. It was a bit odd when I saw it at first, because it was a four section head with one green ball at the bottom.

This setup is installed at several of the CFI's along Bangerter. Has anyone seen this anywhere else, and is it allowed by the MUTCD? Wouldn't a setup with only right arrows be better, as the left turns here are already protected only?

Delaware has a vaguely similar setup; see Page 54/118 of http://deldot.gov/information/pubs_forms/manuals/de_mutcd/pdf/Part4-Highway-Traffic-Signals-December-2012-FINAL.pdf

Option:
01A
(DE Revision) On state-maintained roads, in locations where right turns may be prohibited during special circumstances, a shared signal face may be used consisting of the following signal indications: a CIRCULAR GREEN, CIRCULAR YELLOW, CIRCULAR RED  and right-turn RED ARROW. For additional emphasis, the NO TURN ON RED ARROW (R10-11-DE) sign may be used.

In the process of finding this, I did find a memo indicating that Delaware is no longer using the R10-11-DE sign.

As to compliance with the National MUTCD, I'm not seeing anything so far that would prohibit using both a a circular red and red arrow in the same head - probably something that will not be specifically address until someone brings it to FHWA's attention.

Going back to the Utah signal, I would certainly like to know the thought process behind the design there.  Seems to me if they wanted emphasis they could have gone with two red arrows and should have also used a far side head for the right turn.

[PurdueBill]

I remember the Delaware R10-11-DE sign and always disliked that the arrow depicted was a regular arrow; it seemed possibly confusing that the sign means "no right turn on red arrow" vs. "no turn on red to the right" (the latter of which isn't that sensible but you don't know what people will interpret signs as--plenty of drivers probably make off-the-wall interpretations).

That is why I liked this sign in Boulder, Colorado so much that when I noticed it last summer, I took a picture (as I waited dutifully for a green arrow).  It's totally obvious that the sign means no turn on red arrow--it says the word AND depicts a signal head arrow.

[M3019C LPS20]

In NYC they used to use two section lights lacking a yellow.  It was allowed as the MUTCD did grandfather them in like side mount signals in Washington, DC and here in San Fran. 

I would not necessarily say the two-color traffic signals were exempt from new standards established in the early-1950s in New York City, because of the fact that the city's then Department of Traffic had a limited budget to modernize existing signalized intersections with three-color traffic signals. It was frankly a lengthy process, in which took around 54 years to complete.

[SignBridge]

By the 1970's most traffic signals in NYC had been changed over to 3-color type.

[M3019C LPS20]

Yes, I would agree. That was mainly because the city's D.O.T. was in the process of modernizing major roads with computerized signal controllers. Queens was the first borough to have the technology first implented in 1969. Even so, quiet neighborhoods in areas of the city (with the exception of Staten Island) still had two-color traffic signals fully operable. They remained until their ultimate demise around 2006, and the last vehicular Ruleta traffic signals of the early-20th century remained until the beginning of the new millenium.

[Revive 755]

I remember the Delaware R10-11-DE sign and always disliked that the arrow depicted was a regular arrow; it seemed possibly confusing that the sign means "no right turn on red arrow" vs. "no turn on red to the right" (the latter of which isn't that sensible but you don't know what people will interpret signs as--plenty of drivers probably make off-the-wall interpretations).

There's also this non-standard version used in Lincoln, Nebraska:  Streetview

[plain]

Right-on-red is not allowed on red arrows in UT. To add to the overkill, there is an electronic no right turn sign which turns off when the light is green/yellow. Seems like a waste when you could just put a "no turn on red" sign there, which is usually what is done at intersections where RTOR isn't allowed.

The reason right-on-red isn't allowed here is because this is a CFI, and a right on red here would conflict with the left turn movement from northbound Bangerter to 5400 S westbound, and the same goes for the opposite side.

If right turn is allowed on red, they will use a 3-head signal with a red ball and yellow/green arrows.

What's up with those green down arrows in the background over the left lane? Is that some sort of reversible lane or something?

[Revive 755]

^ Looks like the center two lanes become reversible farther down - or as Utah seems to call, "flex lanes". 

Then there's also this interesting looking signal farther down.

[US 89]

^ Looks like the center two lanes become reversible farther down - or as Utah seems to call, "flex lanes". 

Then there's also this interesting looking signal farther down.

If you're talking about the one with two red lights on top, that is done to emphasize the red signal. My best guess for why it's done here is that there might be a lot of crashes caused by people running res lights here.

[thenetwork]

^ Looks like the center two lanes become reversible farther down - or as Utah seems to call, "flex lanes". 

Then there's also this interesting looking signal farther down.

Affectionately known as Dolly Parton signals!