Anyone seen signals like these? They are for streetcars, light rail and (sometimes) buses.
These are from Sweden, though I have seen them in other EU nations, but never in the U.S. or Canada. Always white in color, but the signal heads do not generally have any marking saying "transit vehicles only."
Stop:
(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fwww.transportstyrelsen.se%2FVagmarken%2FTrafiksignaler%2FSIG8%2FSIG8-1%2Fladdahem%2FSIG8-1.png&hash=07d173617e4d96d2e258928ab053c899f7de21c0)
| "Prepare to stop:"
(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fwww.transportstyrelsen.se%2FVagmarken%2FTrafiksignaler%2FSIG11%2FSIG11-1%2Fladdahem%2FSIG11-1.png&hash=a72848fb035d0a9e8127f94dd4a9eadc2c00bf19)
| "Prepare to go:"
(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fwww.transportstyrelsen.se%2FVagmarken%2FTrafiksignaler%2FSIG9%2FSIG-9%2Fladdahem%2FSIG9-1.png&hash=079b85714fb7b5e1cf8d295c92696399c06246dd)
| Go (I've also seen this one with an arrow instead of a vertical line):
(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fwww.transportstyrelsen.se%2FVagmarken%2FTrafiksignaler%2FSIG10%2FSIG10-1%2Fladdahem%2FSIG10-1.png&hash=3128ad0324dcb44fb377ea9d131b9498a3b68117)
|
I've seen some in Russia, although when I saw them I didn't necessarily realize exactly what they were for. Here's a Google Street View link to a spot I remember on Moskovsky Prospekt in St Petersburg. (http://goo.gl/maps/8UKfo) Notice the white rectangular sign reading "Stop" that's above that silver station wagon in the left lane. There are two small traffic signals to the left of that. They're for the trams that use those tracks in the median.
The ones I saw in Tallinn were closer to what you've posted. Here's a Street View to one example; it's a bit hard to see, but if you look to the left of the man on the rollerblades you'll see the white "S." (http://goo.gl/maps/6zAsD)
I may have seen something similar elsewhere, but I just don't recall. I've never been to Australia, but I hear there are a lot of trams in Melbourne and so I'd expect to see transit-only signals there.
As far as the USA and Canada go, though–I don't go to Baltimore very often, but I recall the light rail uses the streets and so I assumed there has to be some sort of signal dedicated to them. I found this Street View image from the area near the ballpark. See the two boxes up high to the left of the Holiday Inn sign. (http://goo.gl/maps/GMbGJ) They're not for pedestrians since those are lower to the right. They're not for cars since it's a one-way street on the part behind where the camera is located. Only other possibility is for transit.
Orlando's bus-only lane has these, except with no "S". I think it's roughly analogous to railroad semaphores.
Quote from: 1995hoo on August 15, 2012, 11:14:46 AM
I've seen some in Russia, although when I saw them I didn't necessarily realize exactly what they were for. Here's a Google Street View link to a spot I remember on Moskovsky Prospekt in St Petersburg. (http://goo.gl/maps/8UKfo) Notice the white rectangular sign reading "Stop" that's above that silver station wagon in the left lane. There are two small traffic signals to the left of that. They're for the trams that use those tracks in the median.
Never been in Russia, but I see what you mean.
Quote from: 1995hoo on August 15, 2012, 11:14:46 AM
The ones I saw in Tallinn were closer to what you've posted. Here's a Street View to one example; it's a bit hard to see, but if you look to the left of the man on the rollerblades you'll see the white "S." (http://goo.gl/maps/6zAsD)
Been in Talinn (though not recently, in the 1990's, just a few years after the Soviet Union went out of business), though at the time, I do not recall seeing those signals.
Many of the transit buses they were running in Talinn then were retired from fleets in Finland and Sweden.
Quote from: 1995hoo on August 15, 2012, 11:14:46 AM
I may have seen something similar elsewhere, but I just don't recall. I've never been to Australia, but I hear there are a lot of trams in Melbourne and so I'd expect to see transit-only signals there.
As far as the USA and Canada go, though–I don't go to Baltimore very often, but I recall the light rail uses the streets and so I assumed there has to be some sort of signal dedicated to them. I found this Street View image from the area near the ballpark. See the two boxes up high to the left of the Holiday Inn sign. (http://goo.gl/maps/GMbGJ) They're not for pedestrians since those are lower to the right. They're not for cars since it's a one-way street on the part behind where the camera is located. Only other possibility is for transit.
I am in Baltimore City somewhat frequently, and have seen those from time to time - they are indeed for the light rail.
It's only on Howard Street where the Central Light Rail has to mix it up with street traffic for any distance. Along other parts of the line, it's much more like a railroad operation (and the crossings have railroad-style signals and gates).
In a perfect world, perhaps Maryland SHA would add those transit signal heads to its state MUTCD supplement?
Getting back to the other side of the pond, here (http://maps.google.se/maps?q=mannerheimv%C3%A4gen+%2F+runebergsgatan,+Helsingfors,+Finland&hl=sv&ie=UTF8&ll=60.181392,24.927635&spn=0.047716,0.154324&sll=61.606396,21.225586&sspn=11.726107,39.506836&hq=mannerheimv%C3%A4gen+%2F+runebergsgatan,&hnear=Helsingfors,+Finland&t=m&z=13&layer=c&cbll=60.181499,24.927582&panoid=sNmPwjQ4qCIjEonzwQ0yEA&cbp=12,356.9,,0,-1.2) is a GSV shot from the intersection of Mannerheim Way and Runeberg Street in Helsingfors (Helsinki), Finland.
It's a
very busy urban intersection at peak commute times, with rubber-tired vehicles and streetcars (1 meter gauge) turning in several directions. Note the double signal heads for transit (in this case streetcars) - one is for straight ahead, and one is to allow them to make a right. On the other side of the intersection is a Variotram (http://en.wikipedia.org/wiki/Variotram) low-floor articulated unit waiting at the light.
My pride in Finland is showing (and I confess same), but the Helsingfors municipal DOT has long done a superb job of integrating the signal systems for the streetcars and rubber-tire traffic - and yes, the streetcars usually get priority treatment from the signal system software. Unfortunately, the same cannot be said about Baltimore, where it seems that the coordination between light rail and rubber-tire traffic has not been very good.
Across the Baltic, Sweden likes to use these same signal heads for buses as well. At this (http://maps.google.se/maps?q=Uppsalav%C3%A4gen,+stockholm&hl=sv&ie=UTF8&ll=59.364345,18.022556&spn=0.012225,0.038581&sll=62.41061,17.289176&sspn=0.01111,0.038581&hnear=Uppsalav%C3%A4gen&t=m&z=15&layer=c&cbll=59.364414,18.022467&panoid=PLQhz7Mar2PlOuyWxK5daw&cbp=12,157.83,,0,13.52) intersection (really the end of a motorway off-ramp), the buses can continue straight back to the motorway ahead but all other traffic must turn left (through traffic is supposed to be on the E4 motorway to the left behind the hedge).
I've been to Helsinki and Stockholm, but in Stockholm we didn't see any of the transit infrastructure and in Helsinki I just don't remember noticing it, although from looking at the map I believe we probably passed through that intersection you've posted. My attention was elsewhere.
Quote from: cpzilliacus on August 15, 2012, 12:57:30 PM
My pride in Finland is showing (and I confess same), but the Helsingfors
your pride in Swedish-speaking Finland, no less! :sombrero:
Boston's Green Line uses white and red line orientation signals for the at-grade intersections.
Don't know the official name for these but that's how I would describe them.
Quote from: agentsteel53 on August 15, 2012, 01:32:05 PM
Quote from: cpzilliacus on August 15, 2012, 12:57:30 PM
My pride in Finland is showing (and I confess same), but the Helsingfors
your pride in Swedish-speaking Finland, no less! :sombrero:
Correct. ;-)
Though I did translate the street names to proper English.
Quote from: 1995hoo on August 15, 2012, 01:16:44 PM
I've been to Helsinki and Stockholm, but in Stockholm we didn't see any of the transit infrastructure and in Helsinki I just don't remember noticing it, although from looking at the map I believe we probably passed through that intersection you've posted. My attention was elsewhere.
Both cities have very well-developed transit systems. Helsinki has but one Metro(rail) line, but many streetcar (tram) lines that serve mostly the core part of the region. Longer-haul transit is by regional (commuter) rail, somewhat like the network run by SEPTA, and, of course, by bus (including some right-side bus-only lanes on motorways). From a highway perspective, the Helsinki region has two 180° circumferential highways (Ring I (http://en.wikipedia.org/wiki/Ring_I) and Ring III (http://en.wikipedia.org/wiki/Ring_III),
Kehä I and
Kehä III in Finnish) (they only go about 180 degrees around because of the coastal nature of the region). Ring I would be considered an expressway under U.S. functional classification, and most of Ring III was originally built as a two-lane highway with partial access control, but is being converted to a freeway most of the way (there's a rural segment at the west end of Ring III that remains a "Super 2"). Where's Ring II (http://en.wikipedia.org/wiki/Keh%C3%A4_II), you ask? A short segment of Ring II is open to traffic as a "Super 2" (including a long bored tunnel section to avoid disturbing parkland), but most of the rest is still in planning. In general, Finland's highway engineers seem to like "Super-2" highways, though a relative of mine was badly injured in a head-on wreck on a rural Super-2 many years ago (he survived and recovered).
Stockholm has a remarkably large Metro (
Tunnelbana in Swedish) system, and the Blue Line is worth a half-day visit, as it has rightly been called the "longest art museum in the world." As an aside, the Blue Line also serves the suburban "Smart Growth disasters" known as Rinkeby (http://en.wikipedia.org/wiki/Rinkeby) and Tensta (http://en.wikipedia.org/wiki/Tensta), which are also worth a visit (in the daytime). I will describe Rinkeby and Tensta in more detail offline if you are interested. Stockholm also has regional rail, which runs far beyond the corporate limits of the city (some have called it "sprawl-inducing," which it probably is). There are only a few suburban streetcar lines (all of the ones in the core area were shut-down prior to the conversion to right-hand traffic in 1967, though there has been some discussion about bringing streetcar service back to some urban corridors in Stockholm). There's also some interesting highway infrastructure to look at, including underground motorways (one complete, one under construction, two are in design).
Quote from: cpzilliacus on August 15, 2012, 01:53:12 PM
I will describe Rinkeby and Tensta in more detail offline if you are interested.
or just do it here... we could probably spawn off a discussion of Stockholm into some other topic.
I had to look up Helsingfors - I had no idea that was the official name for the city in Swedish. I've never been to that part of Finland; just the extreme north.
The city of Camden likes to use these (http://goo.gl/maps/K655j) for the NJ Transit River Line trolley that runs through the city. They basically operate with the traffic signals; vertical line being go, diagonal line being the yellow light, and the horizontal line being stop.
Montreal has some street signals with an additional vertical white bar unit that lights up before the green phase to let buses through so they can safely merge back after having served a stop.
Quote from: NE2 on August 15, 2012, 12:11:11 PM
Orlando's bus-only lane has these, except with no "S". I think it's roughly analogous to railroad semaphores.
In the Philly area, those signals (sans the "S") are along several SEPTA trolley lines.
Quote from: PHLBOS on August 15, 2012, 02:50:16 PM
Quote from: NE2 on August 15, 2012, 12:11:11 PM
Orlando's bus-only lane has these, except with no "S". I think it's roughly analogous to railroad semaphores.
In the Philly area, those signals (sans the "S") are along several SEPTA trolley lines.
Strangely, I have ridden the streetcars in Philly, but not noticed those. Almost ashamed to say I missed them!
I will have to look more closely the next time I am there.
If I recall correctly, the VTA Light Rail system's signals are (from top to bottom) a red horizontal bar, white triangle and a white vertical bar (or angled if it's a "turn" signal).
Oddly enough when the light rail system opened, the signals for the light rail trains were red, yellow and green "T" symbols. Unfortunately (and I am NOT making this up), drivers, who were obviously unfamiliar with these signals, interpreted the light rail signals as left-turn signals ("T" means "turn"! :banghead:) and were making left turns in front of the light rail trains. The VTA changed the color of the bottom signal from green to white as a temporary fix before installing the signals I described above.
The DC Metrorail, which does not have any at-grade crossings, uses red and white to mean "stop" and "go." I recall reading somewhere that red and white are standard colors in railroad operations, although I've never bothered to verify this through any research.
Quote from: PennDOTFan on August 15, 2012, 02:18:32 PM
The city of Camden likes to use these (http://goo.gl/maps/K655j) for the NJ Transit River Line trolley that runs through the city. They basically operate with the traffic signals; vertical line being go, diagonal line being the yellow light, and the horizontal line being stop.
Baltimore does the same, only with two boxes. (http://goo.gl/maps/q5ZKm)
Quote from: kj3400 on August 15, 2012, 04:02:12 PM
Quote from: PennDOTFan on August 15, 2012, 02:18:32 PM
The city of Camden likes to use these (http://goo.gl/maps/K655j) for the NJ Transit River Line trolley that runs through the city. They basically operate with the traffic signals; vertical line being go, diagonal line being the yellow light, and the horizontal line being stop.
Baltimore does the same, only with two boxes. (http://goo.gl/maps/q5ZKm)
And interestingly enough, both the Baltimore and Camden examples are basically retrofitted pedestrian signals.
Quote from: 1995hoo on August 15, 2012, 03:52:19 PM
The DC Metrorail, which does not have any at-grade crossings, uses red and white to mean "stop" and "go." I recall reading somewhere that red and white are standard colors in railroad operations, although I've never bothered to verify this through any research.
There are red, amber and green signal aspects in the signals used by Amtrak, CSX (N.E. Corridor) and NS (I am not enough of a rail geek to explain their meaning).
In the Washington Metrorail system, I know that white means
go, and is called a "lunar" aspect. Never did understand why WMATA uses white and not green for go (or proceed).
Perhaps colorblindness could have been a reason?
Quote from: cpzilliacus on August 15, 2012, 04:43:58 PM
Quote from: 1995hoo on August 15, 2012, 03:52:19 PM
The DC Metrorail, which does not have any at-grade crossings, uses red and white to mean "stop" and "go." I recall reading somewhere that red and white are standard colors in railroad operations, although I've never bothered to verify this through any research.
There are red, amber and green signal aspects in the signals used by Amtrak, CSX (N.E. Corridor) and NS (I am not enough of a rail geek to explain their meaning).
In the Washington Metrorail system, I know that white means go, and is called a "lunar" aspect. Never did understand why WMATA uses white and not green for go (or proceed).
Actually, the Baltimore Metro uses white for go too. But their signals are only used at crossovers. And there's two reds for some reason. And it's always set on 'go.'
Quote from: cpzilliacus on August 15, 2012, 03:05:34 PM
Quote from: PHLBOS on August 15, 2012, 02:50:16 PM
Quote from: NE2 on August 15, 2012, 12:11:11 PM
Orlando's bus-only lane has these, except with no "S". I think it's roughly analogous to railroad semaphores.
In the Philly area, those signals (sans the "S") are along several SEPTA trolley lines.
Strangely, I have ridden the streetcars in Philly, but not noticed those. Almost ashamed to say I missed them!
I will have to look more closely the next time I am there.
I said Philly
area, which doesn't necessarily include the city itself. More specifically, the SEPTA Route 101 & 102 trolleys in Delaware County that run from the 69th St. Terminal in Upper Darby to Media (Route 101) and Sharon Hill (Route 102) have those type of signals at many street crossings.
The only reason why I wasn't more location-specific before was in case there were similar signals existed on other SEPTA trolley lines in the City of Philadlephia itself that I wasn't aware of.
I've seen something like that (meaning white signals) in Cleveland and San Francisco. I seem to remember a triangle for one of the phases, though. Now that I think about it, Charlotte has (had?) a bus lane down the middle of Independence Blvd that had one of those signals at its end (Albemarle or Sharon Amity, can't remember which one.) I've only ever seen it when the line is in the middle of the road, though.
Quote from: agentsteel53 on August 15, 2012, 02:00:05 PM
Quote from: cpzilliacus on August 15, 2012, 01:53:12 PM
I will describe Rinkeby and Tensta in more detail offline if you are interested.
or just do it here... we could probably spawn off a discussion of Stockholm into some other topic.
I had to look up Helsingfors - I had no idea that was the official name for the city in Swedish. I've never been to that part of Finland; just the extreme north.
The name
Helsingfors likely pre-dates
Helsinki (many place names in Finnish in some parts of Finland are adapted from the Swedish). I make that assertion only because the name was established while Finland was part of the Swedish empire (as it was up to 1809).
Saw them in Las Vegas (of all places) for a bus lane. Just LRT signals according to the latest MUTCD, no big deal...
Obviously they want to differentiate them from traffic signals so cars don't obey them and so buses/trams know to not obey the "normal" lights.
In the cases of heavy rail systems, naturally, traditional signals are used. Red, yellow, and green mean pretty much exactly what you'd expect, though it gets more complicated when you have switches.
Quote from: Duke87 on August 15, 2012, 08:59:18 PM
Saw them in Las Vegas (of all places) for a bus lane. Just LRT signals according to the latest MUTCD, no big deal...
Obviously they want to differentiate them from traffic signals so cars don't obey them and so buses/trams know to not obey the "normal" lights.
Obviously the white color make sense for that reason.
Thanks for sharing your knowledge. I have
never seen anything close to the original signals above in the United States, and did not know they were in the MUTCD until your post. See this (http://mutcd.fhwa.dot.gov/htm/2009/part8/fig8c_03_longdesc.htm) for the details.
These would seem to make a lot of sense in intersections with heavy volumes of transit bus traffic, though the MUTCD says the signals are for rail vehicles and makes no mention of buses in that description, though the text appears to allow them for queue jump applications.
Quote from: Duke87 on August 15, 2012, 08:59:18 PM
In the cases of heavy rail systems, naturally, traditional signals are used. Red, yellow, and green mean pretty much exactly what you'd expect, though it gets more complicated when you have switches.
Though as discussed above, the Washington Metrorail system's trackside signals do not include green - only red and white (a "lunar" aspect) for "GO."
The Hiawatha LRT in the Twin Cities uses a modified version of the signals at the top of the page.
For the record, on heavy rail:
Double red: Stop.
Single Red (or double red, units not aligned): Stop and go, restricted speed (under 15 mph and watch for traffic; no clearance guarantee). Might mean Stop for some light rail systems.
Yellow or Yellow over Red: Proceed, next signal is red.
Green or Green over Red: Proceed at normal speed.
Position light signals: horizontal is red, diagonal is yellow, vertical is green. Amtrak uses coloured lenses on theirs but not everyone else does. And exceptions exist.
Like Duke87 mentioned, the presence of switches, interlockings and even grades and phase breaks make the whole thing get very complicated quickly, since the signals will give you instructions about the speed at which to get through and what to do afterwards. This is why some signals have two or three units, able to display combinations of colours called "aspects". And I won't even get started about dwarf signals, which are interpreted differently. To make things worse, many companies throw in extra custom signal aspects. BNSF is especially bad for this. In countries where signals aren't actually standardized, what I said above is subject to variation. Canada has a federal standard which must be complied to, I don't know about the U.S.
That said, I don't think it's wise to use colour signals on street runs, especially when those are frequent and/or traffic is dense. I'd rather see plain white lights with symbols (as seen at the beginning of this thread) or position lights (common on heavy rail in the U.S. from what I've heard).
Quote from: Dr Frankenstein on August 15, 2012, 11:59:21 PM
For the record, on heavy rail:
Double red: Stop.
Single Red (or double red, units not aligned): Stop and go, restricted speed (under 15 mph and watch for traffic; no clearance guarantee). Might mean Stop for some light rail systems.
Yellow or Yellow over Red: Proceed, next signal is red.
Green or Green over Red: Proceed at normal speed.
Position light signals: horizontal is red, diagonal is yellow, vertical is green. Amtrak uses coloured lenses on theirs but not everyone else does. And exceptions exist.
Frank, this is correct. And consider this - when the Øresund bridge-tunnel crossing between Denmark and Sweden, opened, in addition to the motorway crossing, this was the first time that the Danish and Swedish railroad networks had ever been linked (both networks are standard gauge, but prior to 2000, the only connection was by floating freight cars and passenger cars across on ferries). The traction power voltages and the frequency of the power is different, and the signals (including ATC) are quite different. And for more fun, Swedish railroads still run "on the left" on double-track segments.
All of this had to be dealt with when "through" train service across the bridge-tunnel started up in 2000.
Quote from: Dr Frankenstein on August 15, 2012, 11:59:21 PM
Like Duke87 mentioned, the presence of switches, interlockings and even grades and phase breaks make the whole thing get very complicated quickly, since the signals will give you instructions about the speed at which to get through and what to do afterwards. This is why some signals have two or three units, able to display combinations of colours called "aspects". And I won't even get started about dwarf signals, which are interpreted differently. To make things worse, many companies throw in extra custom signal aspects. BNSF is especially bad for this. In countries where signals aren't actually standardized, what I said above is subject to variation. Canada has a federal standard which must be complied to, I don't know about the U.S.
I believe each of the U.S. railroads is to some extent free to set-up signal systems as it wishes to, though I suppose (in the United States) the Federal Railroad Administration could step in and
order a railroad to make changes if it was deemed appropriate.
Quote from: Dr Frankenstein on August 15, 2012, 11:59:21 PM
That said, I don't think it's wise to use colour signals on street runs, especially when those are frequent and/or traffic is dense. I'd rather see plain white lights with symbols (as seen at the beginning of this thread) or position lights (common on heavy rail in the U.S. from what I've heard).
Agreed.
US railroads use several distinct signal types that date to different historical differences between railroads - the different signal types do NOT line up with the modern Class I railroads, because, for example, the Chesapeake & Ohio used a different signal type than the Pennsylvania RR, and both of those ended up at least partially under the CSX umbrella today. Signals you see on the CSX mainline between Albany and Boston differ from the signals you see on the CSX mainline between Richmond and Newport News, VA, for example. Different signals are also used depending on the type of signalling setup, i.e. block signalling/PTC/etc.
My work involves interacting with the Massachusetts Bay Commuter Railroad (former Boston & Maine RR)'s tracks, and from this and talking with their flagmen I've learned that our signals, which are 3 round single-lens heads, mean as follows:
-Top lens: Green - proceed
Amber - proceed at reduced speed
Red - stop
-Middle lens: Always remains red except in the case of a special condition in the block AFTER next. i.e. a green on top and a yellow in the middle means proceed prepared to reduce speed at the next signal.
-Bottom lens: I don't recall exactly what this means, but I believe it regulates speed somehow, and was told it's almost never, ever, used.
In the several months I've worked here, I've never seen a signal display anything other than all red or green/red/red. It's very uncommon.
Quote from: deathtopumpkins on August 16, 2012, 02:35:51 PM
US railroads use several distinct signal types that date to different historical differences between railroads - the different signal types do NOT line up with the modern Class I railroads, because, for example, the Chesapeake & Ohio used a different signal type than the Pennsylvania RR, and both of those ended up at least partially under the CSX umbrella today. Signals you see on the CSX mainline between Albany and Boston differ from the signals you see on the CSX mainline between Richmond and Newport News, VA, for example. Different signals are also used depending on the type of signalling setup, i.e. block signalling/PTC/etc.
And we have CTC (http://en.wikipedia.org/wiki/Centralized_traffic_control).
I am not an expert on train signals, I only know about CTC because CSX uses it on at least some of its (former B&O) tracks in the Baltimore/Washington area.
Portland has similar signals for its MAX and Streetcar systems. Not aware of too many bus-only signals other than queue-jumper lights (which look like regular traffic signals but are usually PV heads mounted with a "bus only" sign next to it).
Most MAX signals are two head with an amber left-right bar and a white up-down bar. Amber means stop, white means go. The amber signal will flash before it turns to white; the white signal will flash before it turns to amber.
Near switches there are additional signals.
Here in Australia we do have special signals for buses and trams, as mentioned here (http://expressway.paulrands.com/gallery/signals/index.html):
Bus Signal - Red:
Red means any buses must stop. They must wait behind the stop line. Do not go through the intersection.
(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fexpressway.paulrands.com%2Fimages%2Fsignals%2Fbus_red.png&hash=2cc67bcfa0e1cb7c68f89f8fec8c7f8690bfd247)
Bus Signal - Amber:
Amber means any buses must stop. They can enter the intersection if they are so close to the stop line that sudden braking might cause a crash.
(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fexpressway.paulrands.com%2Fimages%2Fsignals%2Fbus_amber.png&hash=d9b5faafdb73c279209a367b0f884d6cc158a511)
Bus Signal - White:
White means any buses can proceed through the intersection carefully. This light usually comes on before the regular traffic signal turns green.
(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fexpressway.paulrands.com%2Fimages%2Fsignals%2Fbus_white.png&hash=2e2aade2cc79d9fec5d9b5645caff73f827a9952)
Tram Signal - Red:
Red means any trams must stop. They must wait behind at the signal. Do not proceed.
(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fexpressway.paulrands.com%2Fimages%2Fsignals%2Ftram_red.png&hash=0d02913e2ec58a9d5c08776cb8a3fd9f06daa23c)
Tram Signal - Amber:
Amber means any trams must stop. They can continue if they are so close to the stopping point that sudden stopping might cause a crash or injury to passengers.
(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fexpressway.paulrands.com%2Fimages%2Fsignals%2Ftram_amber.png&hash=b48f8fafb0d4aa4d0f58e5c4928fd67051db3a2e)
Tram Signal - White:
White means any trams can proceed carefully.
(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fexpressway.paulrands.com%2Fimages%2Fsignals%2Ftram_white.png&hash=dafdf31931434ac82a604c138de86eb47198e5a2)
Along with the pedestrian signals as shown here,
(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fexpressway.paulrands.com%2Fimages%2Fsignals%2Fped_dontwalk_pictogram.png&hash=f7b4e8d5c9add8da39db81c11db4a09bed5a7572)(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fexpressway.paulrands.com%2Fimages%2Fsignals%2Fped_walk_pictogram.png&hash=b25ec2dac465cb896d3ba7a7434849ec45e70ad2)
I've noticed at a few newer intersections there have also had bicycle signals installed alongside them.
Bicycle Signal - Stop:
Signal especially for bicycle riders, using a red bicycle to indicate 'Stop'.
(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fexpressway.paulrands.com%2Fimages%2Fsignals%2Fbicycle_red.png&hash=afa4bdb31d6d75399379238d3fb82915e9e0c7ee)
Bicycle Signal - Go:
Signal especially for bicycle riders, using a green bicycle to indicate 'Go'.
(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fexpressway.paulrands.com%2Fimages%2Fsignals%2Fbicycle_green.png&hash=5fadd6a05a566b59483b2d54c92eeecce1a1b139)
Quote from: deathtopumpkins on August 16, 2012, 02:35:51 PM
US railroads use several distinct signal types that date to different historical differences between railroads - the different signal types do NOT line up with the modern Class I railroads, because, for example, the Chesapeake & Ohio used a different signal type than the Pennsylvania RR, and both of those ended up at least partially under the CSX umbrella today. Signals you see on the CSX mainline between Albany and Boston differ from the signals you see on the CSX mainline between Richmond and Newport News, VA, for example. Different signals are also used depending on the type of signalling setup, i.e. block signalling/PTC/etc.
Exactly. Old Pennsylvania RR mainlines and Norfolk and Western mainlines used position light signals with white lights. (For a long time, the N&W was controlled by the Pennsy. Side note: Ironically, the N&W merged with the Southern RR to form the modern Norfolk Southern while Pennsy lines became part of the ill-fated Penn Central, then Conrail, then split between CSX and Norfolk Southern.)
The C&O and B&O implemented the similar COLOR position light system with uses positions like the old Pennsy/N&W but with color to clarify the meaning. This included the Alton portion (Chicago-St. Louis) of what was once Gulf, Mobile and Ohio/Illinois Central Gulf. That line is now Union Pacific!
Most other railroads used the traffic light style green-yellow-red or a single light with changeable lenses to change colors.
And, yes, with all the mergers and line sales over the years, all the large class I system have a hodgepodge of signal systems. As time go on and signal lights are replaced, each railroad goes to a single standard. So, the old color and monochrome position light signals in the northeast and midwest are rapidly disappearing.