Traffic signal

[freebrickproductions]

We have several permissive double lefts here in Huntsville. They seem to be rather safe. The only difference is that two people can turn left at once from one direction in the permissive phase instead of just one.

[kj3400]

The only one I can think of in Maryland is at Liberty Heights Av. and Northern Pkwy.

http://goo.gl/maps/b928K

[cl94]

New York has a very limited amount of permissive double rights, several of which are around Buffalo. There's one in Amherst. Region 5 also has a double right that allows turns on red. No signage restricts that movement to the rightmost lane. Tons of accidents here.

[mrsman]

^ I have to admit that sight lines look reasonable.  However, I'm still not sold on it being safe.  I've seen far too many impatient and stupid drivers out there.  While I'm all for weeding out the inept, I do feel bad for a driver going straight in the opposite direction who had the right of way and was guilty of nothing more than being in the wrong place at the wrong time.  Those are the drivers whom I'm looking to protect by making double lefts protected only.  I know one can argue the a left turner doesn't have to turn left during the permissive phase if they feel it's unsafe to do so.  However, if there isn't any protected phase, they may never feel it's safe to turn until after midnight.  I also know that the through vehicles going the opposite way should be in control of their vehicle at all times and be able to slow down to avoid a crash with someone turning left into their path.  However, I am in the group that speed doesn't kill, stupid does.  Unfortunately, we can't fix stupid.

I agree. But then again, how many double lefts are even in Canada? I can't remember any where I've been that weren't at a T intersection.

I would hate to have traffic control be a methodology for implementing a Darwin award.  Traffic control needs to be designed with safety as the primary concern, even at the expense of traffic throughput.  And it should be designed from the point of view of the average driver.  If it's too complicated to allow a permissive double left, then it should not be designed that way.

I can't speak for every state, but I know that CA prohibits permissive double lefts because of the issues that signalman addresses.

[roadman65]

I was noticing that in Ontario that instead of using the green arrow for permissive left turns like we do, they flash their green signals to let motorists know of that specific phase.

Is that a Canada thing or is it only provincial within Ontario?

[jakeroot]

I was noticing that in Ontario that instead of using the green arrow for permissive left turns like we do, they flash their green signals to let motorists know of that specific phase.

Is that a Canada thing or is it only provincial within Ontario?

The only provinces I have set foot in, British Columbia and Alberta, both use flashing green arrows during the protected phase. Otherwise, the signal is just a green orb (unless the signal is protected-only). The purpose is so Canada can, as a whole, avoid the FYA, the doghouse, and other 5-head signals (from a color-blind perspective, the flashing arrow means go, the solid arrow means perhaps you should slow down and yield. No arrow means straight-up yield).

For the record, I prefer this setup compared to doghouses (less power usage) and FYAs (only two signals are required at a standard intersection versus three for an FYA).



Post 1010!

[roadfro]

I was noticing that in Ontario that instead of using the green arrow for permissive left turns like we do, they flash their green signals to let motorists know of that specific phase.

Is that a Canada thing or is it only provincial within Ontario?

The only provinces I have set foot in, British Columbia and Alberta, both use flashing green arrows during the protected phase. Otherwise, the signal is just a green orb (unless the signal is protected-only). The purpose is so Canada can, as a whole, avoid the FYA, the doghouse, and other 5-head signals (from a color-blind perspective, the flashing arrow means go, the solid arrow means perhaps you should slow down and yield. No arrow means straight-up yield).

For the record, IIRC, Canada had the flashing circular green before the FYA was mainstream in the U.S. Since Canada is a different country, they aren't under obligation to adopt FYA or any other signal scheme, unless there's some treaty clause somewhere that I've never heard about.

[jakeroot]

I was noticing that in Ontario that instead of using the green arrow for permissive left turns like we do, they flash their green signals to let motorists know of that specific phase.

Is that a Canada thing or is it only provincial within Ontario?

The only provinces I have set foot in, British Columbia and Alberta, both use flashing green arrows during the protected phase. Otherwise, the signal is just a green orb (unless the signal is protected-only). The purpose is so Canada can, as a whole, avoid the FYA, the doghouse, and other 5-head signals (from a color-blind perspective, the flashing arrow means go, the solid arrow means perhaps you should slow down and yield. No arrow means straight-up yield).

For the record, IIRC, Canada had the flashing circular green before the FYA was mainstream in the U.S. Since Canada is a different country, they aren't under obligation to adopt FYA or any other signal scheme, unless there's some treaty clause somewhere that I've never heard about.

I would imagine that the only reason our traffic signals are even remotely similar, is probably due to the NAFTA (or its predecessor, the FTA). Before the 80s, IIRC, Canadian and American traffic control systems had greater variation than there is now. Not a lot, but more.

But back to the topic, I can't think of any reason that Canada would need to adopt the FYA. It seems that their version, just a solid green orb after the flashing arrow phase, works perfectly well. Now with that said, I am not a signal expert, so I'm not sure if the yellow trap still exists in this situation or not. And if it did, whether or not it would need to be addressed at all.

[Brandon]

I would imagine that the only reason our traffic signals are even remotely similar, is probably due to the NAFTA (or its predecessor, the FTA). Before the 80s, IIRC, Canadian and American traffic control systems had greater variation than there is now. Not a lot, but more.

Nope.  It's due to mere proximity, not NAFTA.  Prior to NAFTA, they were sill very similar.  Even the FMVSS and CMVSS are very similar regarding automobiles (and that dates back to the 1960s).

[jakeroot]

I would imagine that the only reason our traffic signals are even remotely similar, is probably due to the NAFTA (or its predecessor, the FTA). Before the 80s, IIRC, Canadian and American traffic control systems had greater variation than there is now. Not a lot, but more.

Nope.  It's due to mere proximity, not NAFTA.  Prior to NAFTA, they were sill very similar.  Even the FMVSS and CMVSS are very similar regarding automobiles (and that dates back to the 1960s).

Perhaps not precisely NAFTA, but the concept of free-flow between our two countries has lead to ideas being shared between the two countries. Of course, that's due to proximity as you mentioned.

Also, I remind you that, until the 70s, Canada used a white center line with a yellow shoulder. Certainly by the 70s, America was well into yellow center lines. That's a huge difference, IMO.

[cl94]

I would imagine that the only reason our traffic signals are even remotely similar, is probably due to the NAFTA (or its predecessor, the FTA). Before the 80s, IIRC, Canadian and American traffic control systems had greater variation than there is now. Not a lot, but more.

Nope.  It's due to mere proximity, not NAFTA.  Prior to NAFTA, they were sill very similar.  Even the FMVSS and CMVSS are very similar regarding automobiles (and that dates back to the 1960s).

Perhaps not precisely NAFTA, but the concept of free-flow between our two countries has lead to ideas being shared between the two countries. Of course, that's due to proximity as you mentioned.

Also, I remind you that, until the 70s, Canada used a white center line with a yellow shoulder. Certainly by the 70s, America was well into yellow center lines. That's a huge difference, IMO.

Incorrect. MUTCD didn't require them until 1971 and there was a 4 year transition period that followed. From what I can tell, Canada changed over before then.

[jakeroot]

I would imagine that the only reason our traffic signals are even remotely similar, is probably due to the NAFTA (or its predecessor, the FTA). Before the 80s, IIRC, Canadian and American traffic control systems had greater variation than there is now. Not a lot, but more.

Nope.  It's due to mere proximity, not NAFTA.  Prior to NAFTA, they were sill very similar.  Even the FMVSS and CMVSS are very similar regarding automobiles (and that dates back to the 1960s).

Perhaps not precisely NAFTA, but the concept of free-flow between our two countries has lead to ideas being shared between the two countries. Of course, that's due to proximity as you mentioned.

Also, I remind you that, until the 70s, Canada used a white center line with a yellow shoulder. Certainly by the 70s, America was well into yellow center lines. That's a huge difference, IMO.

Incorrect. MUTCD didn't require them until 1971 and there was a 4 year transition period that followed. From what I can tell, Canada changed over before then.

Research fails me once again.

[Revive 755]

Regarding permissive double left movements, there are at least four intersections with them in Chicagoland:

* Thorndale Avenue at Park Boulevard in Itasca, hte signal is maintained by DuPage County.  This intersection has a permissive double left EB, SB has the center lane marked for left-thru-right, effectively providing a permissive double left and a double right without any restrictions for the inner right turn on red.

* Sunset Ridge Road at Skokie Boulevard, signal is maintained by Cook County IIRC.

* Joliet Street at Cass Street in downtown Joliet.

* IL 50/Cicero Avenue at the north outer road for I-290 (Chicago signal)


I remember reading online somewhere that permissive double lefts can work well if they are offset enough.

[M3019C LPS20]

There are a couple of them in different areas of New York City as well.

[cl94]

There are a couple of them in different areas of New York City as well.

Are all on one-way streets? I wasn't counting them because there's no opposing traffic, but I know of a few that fit this description.

[M3019C LPS20]

There are a couple of them in different areas of New York City as well.

Are all on one-way streets? I wasn't counting them because there's no opposing traffic, but I know of a few that fit this description.

While that is true, I did not refer to those on one-way streets there. Such lanes are found on two-lane thoroughfares throughout the boroughs. I personally know of several. One in particular was altered several years ago.

[cl94]

There are a couple of them in different areas of New York City as well.

Are all on one-way streets? I wasn't counting them because there's no opposing traffic, but I know of a few that fit this description.

While that is true, I did not refer to those on one-way streets there. Such lanes are found on two-lane thoroughfares throughout the boroughs. I personally know of several. One in particular was altered several years ago.

Son of a bitch. Other direction is pretty minor, but still.

[mrsman]

There are a couple of them in different areas of New York City as well.

Are all on one-way streets? I wasn't counting them because there's no opposing traffic, but I know of a few that fit this description.

While that is true, I did not refer to those on one-way streets there. Such lanes are found on two-lane thoroughfares throughout the boroughs. I personally know of several. One in particular was altered several years ago.

Now are some of the issues regarding sight lines also an issue if you are on a 2-way street, but the street that you are turning onto is one-way.  It would seem to me that the biggest culprit for blocking sight lines in a double left situation are opposing left turns, not the other cars in the other lane making your left turn.  So if there are no opposing left turns because you are turning onto a one-way street (or the street you are turning onto terminates at this intersection) then a permissive double left should be allowed.

[M3019C LPS20]

Ozone Park, Queens, N.Y. set-up. From 2005. New and old sections that were in use.

[roadman65]

https://www.google.com/maps/@36.7314247,-77.5197958,3a,75y,51.99h,81.83t/data=!3m4!1e1!3m2!1sFHcOEzYSYcWRFa1uyso4ew!2e0 I was always wondering why left turn lanes always flash red as red means that you must come to a complete stop before turning.  Making a left turn anywhere does not require a full stop under law, unless someone is coming.  Therefore left turn signals should be flashing yellow.

Anyway here is one in Virginia along US 301 that is not a full signal, but flashes a red left turn for turning left here at an intersection near Emporia.

[kj3400]

I think it's so you're not fooled into thinking you have the right of way, since you're crossing a stream of traffic that does.

[Joe The Dragon]

Regarding permissive double left movements, there are at least four intersections with them in Chicagoland:

* Thorndale Avenue at Park Boulevard in Itasca, hte signal is maintained by DuPage County.  This intersection has a permissive double left EB, SB has the center lane marked for left-thru-right, effectively providing a permissive double left and a double right without any restrictions for the inner right turn on red.



I remember reading online somewhere that permissive double lefts can work well if they are offset enough.

Going away with the EOE

[mrsman]

https://www.google.com/maps/@36.7314247,-77.5197958,3a,75y,51.99h,81.83t/data=!3m4!1e1!3m2!1sFHcOEzYSYcWRFa1uyso4ew!2e0 I was always wondering why left turn lanes always flash red as red means that you must come to a complete stop before turning.  Making a left turn anywhere does not require a full stop under law, unless someone is coming.  Therefore left turn signals should be flashing yellow.

Anyway here is one in Virginia along US 301 that is not a full signal, but flashes a red left turn for turning left here at an intersection near Emporia.

I don't know why there is a separate left turn signal there at all.

With the two flashing yellows, it should be understood that this is an intersection where only cross traffic has a stop sign.  And in that type of intersection, left turns yield to oncoming traffic with or without flashing lights.

[jakeroot]

Someone please help me figure this out. I shot this video on Friday in Bremerton, Washington (at this crosswalk).

[riiga]

Someone please help me figure this out.

Broken signal? They flash amber like that in Europe in case of a broken signal, but then it's usually all traffic lights in the intersection. Or perhaps if it's a turn lane it might be a warning signal/proceed with caution?