Traffic Signals: Yellow or Black?

[wisvishr0]

I can confirm that most newer signals in Maryland have the black front and yellow back, and also that new installations are mast-arms.

I'm really glad: I always thought yellow signals were hard to see from far away. For example, see these older signals in Bethesda:

https://www.google.com/maps/@38.988148,-77.094961,3a,39.3y,342.95h,90.02t/data=!3m4!1e1!3m2!1s4FYadxI3zg-uDB6iYPkh8g!2e0

I guess that could just be because the signals are so small, but the yellow does kind of limit the contrast.

I'm actually of the opinion that signals should have a black background, with a white border, like they have in the UK (except with another black border around the white border).



Why? Because regulatory signs are always white with a black border, and I've always thought of signals as obligatory signs that change color every once in a while. It just sits well for me if traffic signals are designed consistently like a sign.

[jakeroot]

I'm actually of the opinion that signals should have a black background, with a white border, like they have in the UK (except with another black border around the white border).



Why? Because regulatory signs are always white with a black border, and I've always thought of signals as obligatory signs that change color every once in a while. It just sits well for me if traffic signals are designed consistently like a sign.

I would agree with this, but the next reply will be someone claiming that the white border doesn't increase the visibility. I am of the position that if you miss the huge bulb but somehow see the yellow border, you probably shouldn't be driving. White borders are definitely a favorite of mine.

[freebrickproductions]

Or we could always use massive sign-blank backgrounds like what Huntsville's used in the past...

[DaBigE]

I can confirm that most newer signals in Maryland have the black front and yellow back, and also that new installations are mast-arms.

I'm really glad: I always thought yellow signals were hard to see from far away. For example, see these older signals in Bethesda:

https://www.google.com/maps/@38.988148,-77.094961,3a,39.3y,342.95h,90.02t/data=!3m4!1e1!3m2!1s4FYadxI3zg-uDB6iYPkh8g!2e0

I guess that could just be because the signals are so small, but the yellow does kind of limit the contrast.

I'm actually of the opinion that signals should have a black background, with a white border, like they have in the UK (except with another black border around the white border).



Why? Because regulatory signs are always white with a black border, and I've always thought of signals as obligatory signs that change color every once in a while. It just sits well for me if traffic signals are designed consistently like a sign.

I would agree that a white border techinically fits better, but yellow and black have the best contrast.

[Ian]

New Hope, PA





There are similar signals down in Bristol as well.

[jakeroot]

I would agree that a white border techinically fits better, but yellow and black have the best contrast.

That's not to say black and white don't have extreme contrast . . . they are considered to be exact opposites. I think yellow is more often associated with caution thus the use of a yellow border.

I think that, especially in early morning/late night crashes, where visibility is key, a white border would have just as good retroreflectivity abilities as a yellow border. Imagine a white border in this case:



The study that proved the border around a signal increased visibility was mainly due to the reflective nature of the border, not necessarily the color of the border. If you look at the study (here), you can see the biggest drop in crashes was in the early morning/late night hours, where a reflectivity is more important than color.

At this point, as you suggested DaBigE, aesthetics become the key component.

[dfnva]

I like Ohio's newer signals -- the black signals look snazzy and are easy to see with the new backplates with the yellow reflective strip.

[roadman65]

What is going on with Texas lately?  I noticed that in Houston and Galveston the signal heads are mostly black. However in the DFW Metroplex and in many rural areas along IH 30 they are yellow as well as South Texas and San Antonio (or at least back in 97 when I did that particular city).

Is that a statewide thing or is it just regional where only the Greater Houston area is doing themselves?

[DaBigE]

I would agree that a white border techinically fits better, but yellow and black have the best contrast.

That's not to say black and white don't have extreme contrast . . . they are considered to be exact opposites. I think yellow is more often associated with caution thus the use of a yellow border.

I think that, especially in early morning/late night crashes, where visibility is key, a white border would have just as good retroreflectivity abilities as a yellow border. Imagine a white border in this case:



The study that proved the border around a signal increased visibility was mainly due to the reflective nature of the border, not necessarily the color of the border. If you look at the study (here), you can see the biggest drop in crashes was in the early morning/late night hours, where a reflectivity is more important than color.

At this point, as you suggested DaBigE, aesthetics become the key component.

It's not just aesthetics, (in that case, the white looks better, IMO). There have been color studies, and the yellow/black combination has the better contrast value than white/black. (That's why clearance markers are black and yellow). When Wisconsin was considering redesigning their standard license plates, they considered reverting back to black/yellow for that reason (the same as what they had back in the 1970s). However, they kept the white background, but changed the alpha/numerics from red to black.

Some of the newer computer keyboards marketed to older folks have yellow keys with black letters for that reason as well.

[jeffandnicole]

I would agree that a white border techinically fits better, but yellow and black have the best contrast.

That's not to say black and white don't have extreme contrast . . . they are considered to be exact opposites. I think yellow is more often associated with caution thus the use of a yellow border.

I think that, especially in early morning/late night crashes, where visibility is key, a white border would have just as good retroreflectivity abilities as a yellow border. Imagine a white border in this case:



The study that proved the border around a signal increased visibility was mainly due to the reflective nature of the border, not necessarily the color of the border. If you look at the study (here), you can see the biggest drop in crashes was in the early morning/late night hours, where a reflectivity is more important than color.

At this point, as you suggested DaBigE, aesthetics become the key component.

I'd rather see a real-life contrast example.  Not one where someone drew a orange border on a picture.

[jakeroot]

I would agree that a white border techinically fits better, but yellow and black have the best contrast.

That's not to say black and white don't have extreme contrast . . . they are considered to be exact opposites. I think yellow is more often associated with caution thus the use of a yellow border.

I think that, especially in early morning/late night crashes, where visibility is key, a white border would have just as good retroreflectivity abilities as a yellow border. Imagine a white border in this case:

The study that proved the border around a signal increased visibility was mainly due to the reflective nature of the border, not necessarily the color of the border. If you look at the study (here), you can see the biggest drop in crashes was in the early morning/late night hours, where a reflectivity is more important than color.

At this point, as you suggested DaBigE, aesthetics become the key component.

I'd rather see a real-life contrast example.  Not one where someone drew a orange border on a picture.

I'll see if I can snag one tonight near my house. I'll report back when I can.

[MillTheRoadgeek]

OK, so I have noticed that three signals in the jurisdiction Manassas Park have entirely black signals (the mast arms too).

[dfnva]

OK, so I have noticed that three signals in the jurisdiction Manassas Park have entirely black signals (the mast arms too).

The VDOT standard is a yellow signal with a black backplate, but independent cities and towns have a lot of different variations...
* Fairfax City -- most new signals since the early 1990s are black, some with black backplates
* Vienna -- Some use of black backplates with yellow borders (the only place in VA I've seen this)
* Roanoke -- exclusively uses black signals
* Manassas City -- black signals mostly near the downtown area
* Culpeper -- Downtown -- black signals with black backplates with a white border
* Newport News, Hampton, Norfolk, Chesapeake, and Virginia Beach have both black signals and yellow signals.

I know of two VDOT-installed signal installations with black signals -- US-50/Lee Jackson Hwy and SR-665/Waples Mill Rd in Fairfax (this is outside of the Fairfax City Limit) and along VA-244/Columbia Pike in downtown Annandale at a fire station.

VDOT also used to install red signals at fire stations.

-Dan

[roadman65]

I remember those red signals as you said for fire stations.

[on_wisconsin]

I would agree that a white border techinically fits better, but yellow and black have the best contrast.

That's not to say black and white don't have extreme contrast . . . they are considered to be exact opposites. I think yellow is more often associated with caution thus the use of a yellow border.

I think that, especially in early morning/late night crashes, where visibility is key, a white border would have just as good retroreflectivity abilities as a yellow border. Imagine a white border in this case:



The study that proved the border around a signal increased visibility was mainly due to the reflective nature of the border, not necessarily the color of the border. If you look at the study (here), you can see the biggest drop in crashes was in the early morning/late night hours, where a reflectivity is more important than color.

At this point, as you suggested DaBigE, aesthetics become the key component.

I'd rather see a real-life contrast example.  Not one where someone drew a orange border on a picture.

The best a quick google could find:


The yellow borders are really the most effective if the intersection is not lit very well. Here in Wisconsin the vast majority of signalized intersections (esp. WisDOT maintained) are decently lit so the necessity of them is less apparent. IMO

[Big John]

^^ It is WisDOT policy to have all signalized intersections lit.  You have to have a special exception to find an unlit one in WI.

[Scott5114]

Keep in mind that in most cases the signal will be lit by a camera flash in a nighttime photo. The lighting from car headlights won't be so dramatic.