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Old 02-02-2003, 09:43 PM
Guybud5 Guybud5 is offline
Join Date: Apr 2002
Location: Pacific Grove, CA
Posts: 127
Horizontal Traffic Lights (Red on the left)

I'm originally from Florida, and in the last year moved to Central California. While in Florida, I noted that usually the traffic lights are mounted horizontally, on black poles that extend from poles on the sides of the street. Some older traffic lights were mounted on wires hanging over the road, in a verticle fashion.

Here's my question... how common is the horizontal as opposed to verticle setup? In this area of California, it seems that lights are ALWAYS mounted vertically, and often on eye or near-eye level posts on the side of the road.

Also, do they still build new traffic lights on the suspended from a wire system?

Old 02-02-2003, 10:01 PM
elmwood elmwood is offline
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Location: Upstate New York
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In New Mexico, almost all traffic lights are mounted horizontally (red on left, green on right, turn arrows to far left) as opposed to vertically (red on top, green on bottom, turn arrows to far left or right). Traffic signals mounted horizontally have a much lower profile than those mounted vertically.

Many new traffic signals in Central Florida are suspended from wires strong from cast concrete Sonotube poles.
Old 02-02-2003, 10:09 PM
hobbes730 hobbes730 is offline
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Location: Austin, TX
Posts: 203
In Austin, almost all lights that I can think of are mounted horizontally on posts over the road. Rarely, they'll be mounted vertically on posts to the side of the road, but only in areas of low visibility and such.
Old 02-02-2003, 10:13 PM
Fuji Kitakyusho Fuji Kitakyusho is offline
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Location: Vancouver, BC, Canada
Posts: 1,052
Here in Vancouver, the lights are all vertical, but they use the horizontal setup in Calgary.

The horizontal mounts are a better idea. Mounting the lights that way keeps them from moving with the wind, preventing damage.
Old 02-02-2003, 10:13 PM
Thaumaturge Thaumaturge is offline
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Location: Bay Area
Posts: 766
In New Jersey, pretty much all posts are mounted vertically. Same situation in California as you now know. Hmm....I've been to the panhandle of Florida but don't remember noticing the stop light orientations. Perahps because I wasn't driving.
Old 02-02-2003, 10:28 PM
Gary T Gary T is offline
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Location: KCMO
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The overwhelming majority of U.S. states use the vertical arrangement.

This site ( ) says "As far as I know [the horizontal] design is only used in
New Mexico and Texas." I could have told him to add Florida to the list, but I'd be surprised if any other states normally use horizontal mounting.
Old 02-02-2003, 10:44 PM
PlanMan PlanMan is offline
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Location: Florida's First Coast
Posts: 622
In NE Fla. most lights are vertical - except in Gainesville, which demands horizontal, but they're wierd down there. Some exceptions are just 'beyond' overpasses, where a vertical signal may not be visible. Also, all new installations in Florida that are within 20 miles of either coast (Atlantic Ocean / Gulf of Mexico) must be "mast arms" - those (mostly) black horizontal metal poles coming off a vertical metal pole. In hurricanes (even weak ones) nearly all the "span wire" signals blow away, while mast arms survive much higher winds. Beyond 20 miles, its optional, but the trend is to mast arms, even tho' they are significantly more expensive and have a 6 month order time.

I work for a large state agency that is heavily involved in transportation.
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Old 02-02-2003, 10:52 PM
TheLoadedDog TheLoadedDog is offline
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Location: Sydney, Australia
Posts: 9,193
Only ever seen horizontal ones in Thailand. The Aussie ones are always vertical.

On a side note, traffic lights suspended on wires seem to me to be a strictly US thing. I immediately think of hurricane film footage with the lights swinging wildly. Am I correct here, or are there other places with suspended lights?
Chat to the Australian and New Zealand Dopers at G'Dope ('merkins and sundry furriners more than welcome). "Check them out" - Cecil Adams
Old 02-02-2003, 11:15 PM
mnemosyne mnemosyne is offline
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Location: Montréal, Québec
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Quebec uses the horizontal light setup. They actually have TWO red lights, on either side of the yellow and green, both turn arrows on the appropriate side. I have always found them to be very visible, and since they are above the road, and not to the side, they aren't usually blocked by traffic (thats something that annoys me alot a some intersections in Ontario, where lights are vertical and sometimes on the side of the road, and other times suspended above).
Old 02-02-2003, 11:18 PM
mnemosyne mnemosyne is offline
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Location: Montréal, Québec
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OH, and also, the lights have particular shapes to help you tell what they are, especially for colour blind drivers. I have only seen this in Quebec, as far as I can remember. Red is a square, Yellow is a diamond (well, a square standing on its point) and Green is a circle.
Old 02-03-2003, 12:15 AM
KeithT KeithT is offline
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Location: Loonland
Posts: 545
The horizontal light arrangement is widespread in Wisconsin and Illinois, usually in conjunction with vertical lights. Typically, you'll see the vertical lights mounted to a post on the right side of the road before the intersection, with an additional set of horizontal lights on a boom extending over the opposite side of the intersection.
Old 02-03-2003, 12:26 AM
Skott Skott is offline
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Posts: 802
As a California resident, I can say that most of the traffic lights I've seen are verticle. However, in a few cities and in the "historical" portion of other cities, the traffic lights are horizontal. I think it was done in order to give an old town feel to the area.
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Old 02-03-2003, 03:26 AM
Sublight Sublight is offline
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Since the Canadians and the Aussies have joined in, we might as well go ahead and make it worldwide. Every traffic light I've seen in Japan has been horizontal.
Old 02-03-2003, 06:45 AM
minor7flat5 minor7flat5 is offline
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Originally posted by Thaumaturge
In New Jersey, pretty much all posts are mounted vertically.
As I recall, Newark has plenty of horizontal lights, (been a while, though). Princeton has horizontal lights. I figure that Newark's horizontal lighting is a sort of urban area kind of thing, but Princeton???
Old 02-03-2003, 07:51 AM
RM Mentock RM Mentock is offline
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Location: Durham, NC, USA
Posts: 3,199
I asked this same question in Florida traffic lights, further down in the thread. The only two responses I got were from Texas, and both acted like every state in the union had horizontal traffic lights. I'm glad we straightened that out.
Old 02-03-2003, 08:04 AM
SirRay SirRay is offline
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Location: The Industrial NorthEast
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In NYC and Long Island (and actually, almost everywhere else I've been in NY), light orientation is vertical except where the lights would be obscured by overpasses, RR bridges, etc.
They put up both wire suspended and mast arm mounted lights, with the only defining trait being bigger intersections usually get the wire suspended ones (although I've seen mast arms replace wire-suspended, and then again I've seen wire-suspended replace mast arms - they seem to love to muck around reconfiguring (perfectly functionally) traffic lights on a daily basis around here...
Old 02-03-2003, 10:07 AM
Hauky Hauky is offline
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In Michigan, the large majority is vertical lights hanging from wires. Of course, in my hometown, I can think of spots with vertical lights attached to booms and one spot with a vertical on the side of the road attached to a light pole. And then, traveling a few miles down the highway to a different city, you can find a whole downtown area with horizontal lights on booms.

When I was little, I always got scared when we drove under the ones hanging from wires if it was stormy out. Those things swing all over the place, and once in a while there is a story in the newspaper of one falling.
Old 02-03-2003, 10:26 AM
asterion asterion is offline
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Originally posted by elmwood
In New Mexico, almost all traffic lights are mounted horizontally (red on left, green on right, turn arrows to far left) as opposed to vertically (red on top, green on bottom, turn arrows to far left or right). Traffic signals mounted horizontally have a much lower profile than those mounted vertically.

Many new traffic signals in Central Florida are suspended from wires strong from cast concrete Sonotube poles.
I'm used to driving in Albuquerque, where almost all major intersections will have both horizontal and vertical lights. Horizontal streching over the street and verticals in the median and/or the right side and even sometimes the left side. Fully controlled lefts generally have their own signals in the median, and protected lefts generally to the far left horizontally or bottom vertically. The smaller intersections seem to tend to have horizontals. Of course, most of these are mounted on actual poles as well, with the only exception I can even come up with off the top of my head anymore being the Wyoming and Menaul intersection (which is a pretty big intersection).
Old 07-12-2011, 10:38 PM
mrsticka mrsticka is offline
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Posts: 1
Here in Nebraska, traffic lights are mounted horizontally all over the state, except for Omaha, intersections with wire span assemblies, the I-80/US 81 interchange in York, including downtown, a couple of intersections in Seward, one in Kearney and one in North Platte.
Old 07-12-2011, 11:57 PM
OldGuy OldGuy is online now
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In CT the vast majority of lights are vertical and hang suspended on wires over the middle of the street. There are some vertical lights on posts at the side of road -- most often in conjunction with overhead. I can't recall ever seeing a horizontal light here.
Old 05-27-2015, 08:31 PM
Solidscooter Solidscooter is offline
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Posts: 2
Here in Texas, all lights are mounted horizontally. I have been searching and searching and cannot find out why... But I work in media and I'm going to get in touch with TxDOT to find out and I'll post back. Where I am in Waco, most all lights are horizontal on mast poles. Some of the smaller towns use wire but most are all on masts. In Dallas and Ft. Worth that's also the case for the most part, except downtown. Houston has a crude mix of wire and mast mounting, but again all horizontal. The main reasons I've come up with why we mount them horizontal in Texas is 1) just to be different or 2) the mounting is more secure. When the lights are mounted on masts, the bracket holds the light at both ends. It might be the same way when the light is mounted on a mast vertical. In my opinion when they're hung on a wire horizontally it looks rediculous, especially the way Houston does it. I think a lot of parts are of the city are like that because the roads are always being worked on. It seems like everywhere you go there's always a lane closed, a pothole covered with a metal plate, etc. etc. so crews are always having to move the signals.
Old 05-28-2015, 08:01 PM
Hari Seldon Hari Seldon is online now
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Way, Way back when I was first driving, 60 years ago, Atlantic City had strange lights. On the long streets (NE to SW) they had red on top and green on the bottom (no yellow, simultaneous green and red signaling the light was changing), while the cross streets had green on top and red on the bottom. The point is that each traffic signal contained only two bulbs that shone in all directions. You got used to it, but it was a problem for my color-blind father.

Someone said that Quebec used horizontal lights. Most of the lights in Montreal are vertical and few are shape coded. I don't think it is that different out of the city. One useful innovation that should be more widely copied: a blinking green is equivalent to a left arrow. Very useful.
Old 05-28-2015, 10:14 PM
Mdcastle Mdcastle is offline
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Posts: 2,019
That would be the Darley Simplex traffic signals that had green on the top for one direction. They also usually had a simple electromechanical controller integrated so the agency would just have to hang it and string AC power to it. They turn up on eBay from time to time, north of $1000 if in decent condition.


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