Roads: Traffic Signals

[W. K. Lis]

Leading and Lagging​

Left Turn Signals Compared​

From link. Best to use the link for the complete references.

There is a lot of confusion and controversy about left turn phasing. This page is intended to remove some of the confusion.

Terminology​

Even the terminology about left turn phasing is confusing, because so many different terms have been used for the same things, and because some of the terms and abbreviations have been used for different things. A complete glossary is provided at the end of the article in Appendix A. For immediate use, here is a list of the unambiguous terms used in the rest of this article:

1. Circular green permissive - Permissive left turns made during a circular green indication.
2. Double-Split Lead-Lag - One leg on the street has leading turn, opposite leg has lagging left turn. Either phase can change first.
3. Dual Lag - Both left turns on the street have simultaneous lagging turn phases.
4. Dual Lead - Both left turns on the street have simultaneous leading turn phases.
5. Dual Split Lag - Both left turns on the street have lagging phases. They can begin at different times.
6. Dual Split Lead - Both left turns on the street have leading phases. They can end at different times.
7. Exclusively/Permissive - No left turn phase. Left turns filter through gaps in oncoming traffic.
8. Exclusively/Protected (E/P) - The left turn is protected during one phase, and is not allowed to proceed otherwise.
9. Flashing Yellow Arrow - An indication where left turns are made through gaps in oncoming traffic.
10. Flashing Yellow Arrow permissive - Left turns made through gaps in oncoming traffic during a flashing yellow arrow indication.
11. Lagging left turn - A sequence where the green left turn arrow is next after the oncoming thru green.
12. Leading left turn - A sequence where the oncoming thru green is next after the green left turn arrow.
13. No-Split Lead-Lag - Left turn phasing where each leg on the street has an exclusive phase.
14. Permissive left turn - An indication where left turns are allowed to filter through gaps in oncoming traffic.
15. Prohibited left turn - An indication where left turns must wait until the indication is no longer displayed.
16. Protected left turn - An indication with a green left turn arrow, where no other traffic can move in conflict with the turn.
17. Protected/Permissive (P/P) - The left turn is protected during part of the cycle and permissive during another part.
18. Single lag - A green left turn arrow is displayed in one direction next after the oncoming thru green.
19. Single lead - The oncoming thru green is displayed next after a green left turn arrow for one leg.
20. Single-Split Lead-Lag - One leg on the street has leading turn, opposite leg has lagging left turn. The leading turn must end first.
21. Yellow trap - Left turns trapped in the intersection with a yellow or red light while oncoming traffic is still moving with a green.

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Note the lack of refreshes to public transit.

 

[W. K. Lis]

When they replaced the "60 km/h" signs on a road in my neighbourhood, they didn't inform anyone. They could have used a "NEW" sign attached to them, keeping them until the bolts rust away.

When they replace a "leading left turn arrow signal" with a "lagging left turn arrow signal" or even one that is both "leading" and "lagging" depending if a public transit vehicle gets true priority, they can add a "NEW" sign to the signal.

From link. (They really should replace the solid red signal with a red arrow.)

 

[SubHuman]

.. I think people don't pay attention to the Flashing Hand anymore. They look at the timer and determine if they can make it across in that time.

In the exotic location of Oshawa, the countdown shows how much time is left for the walk signal.
[sarcasm] How silly of them.[/sarcasm]

 

[reaperexpress]

In the exotic location of Oshawa, the countdown shows how much time is left for the walk signal.
[sarcasm] How silly of them.[/sarcasm]

If they can count down from the beginning of the phase to the end, it means that the phase duration is not determined based on the users currently present at the intersection.

If you try to put a countdown on a signal which does determine green durations in real time, you end up with something which certainly is silly:

 

[W. K. Lis]

If they can count down from the beginning of the phase to the end, it means that the phase duration is not determined based on the users currently present at the intersection.

If you try to put a countdown on a signal which does determine green durations in real time, you end up with something which certainly is silly:

Forces the people to actually LOOK at the traffic signals, and NOT ASSUME.

 

[Woodbridge_Heights]

What else do Montréal and New York City have in common? Both are on islands! Except for the Bronx when it comes to New York City.

Toronto can have a canal running along its city limits so that Toronto can become an island.

I'm pretty sure the entirety of new York State is a no right on red jurisdiction, unless that's changed in recent times..

I distinctly remember signs when crossing the border stating as much.

 

[nfitz]

I'm pretty sure the entirety of new York State is a no right on red jurisdiction, unless that's changed in recent times..

I don't recall ever seeing turns on red restricted anywhere in the USA except New York City, going back to the 1980s.

There did used to be signs on the border from New York to Quebec, when the entire province used to restrict turns.

Edit - looks like New York state changed in 1975, as part of the oil crisis - https://www.nytimes.com/1977/04/11/...-many-in-new-york-and-new-jersey-finding.html

 

[Woodbridge_Heights]

It seems in Toronto and Ontario, they do not want to EVER change their "guide book". I'm sure in Europe, if they want to try something new, they'll just experiment despite the "guide book", and if it works, then the change the "guide book" based on the experience.

Wasn't always that way. Used to be a time where we had "ADVANCED GREEN WHEN FLASHING". That was replaced with the green arrow. BTW. In Québec, their "advanced " turn sometimes occurs AFTER. Some places still don't have arrows, so some are more slow to change than here.

Re the ny driver.
Meh I'd rather someone have the attitude "when in doubt wait it out" rather than just assume other drivers will make way for them. Driving in a foreign jurisdiction can be confusing.

We rented a car while in Curacao and couldn't for the life of us understand what the yellow diamond signs meant (clearly I haven't played enough cities skylines) which indicated that we were on a priority road and that crossing streets were supposed to yield to us. Here there would be at least stop signs for the side streets if not all way stops.

We were also used to our roundabout laws where you yield to the vehicles in the round about and had a few friendly drivers literally stop to let us in bc, I guess, we had the right of way?

 

[Woodbridge_Heights]

I don't recall ever seeing turns on red restricted anywhere in the USA except New York City, going back to the 1980s.

There did used to be signs on the border from New York to Quebec, when the entire province used to restrict turns.

Edit - looks like New York state changed in 1975, as part of the oil crisis - https://www.nytimes.com/1977/04/11/...-many-in-new-york-and-new-jersey-finding.html

Hmm . I've never been to NYC bit we would travel to Syracuse to visit relatives fairly regularly in the 80s and I swear back then N.Y. state had no right on red laws.

I blame the Mandela effect.

 

[Towered]

New lights installed at Dupont and Huron.

 

[mike0001]

Speaking of dangerous crossings I wonder if there are any plans for this crossing that seems incomplete. On the West side there is very clearly a path but currently no traffic signal.

So I was cycling Southbound along here this afternoon (August 27) and saw that they installed a new traffic signal for the crossing! It hasn't been activated yet but it's something to look forward to!

 

[Towered]

New lights installed at Islington and Finchley. This breaks up an exceedingly long stretch of Islington from Dundas all the way to Rathburn that previously had no traffic lights. I would certainly add some more.

 

[W. K. Lis]

New lights installed at Islington and Finchley. This breaks up an exceedingly long stretch of Islington from Dundas all the way to Rathburn that previously had no traffic lights. I would certainly add some more.

Obvious locations should be at bus stops. Maybe adding a few corner stores in the process.

 

[DSC]

Obvious locations should be at bus stops. Maybe adding a few corner stores in the process.

The TTC has been closing stops NOT at traffic light controlled intersections, though there still are some, I think.

 

[W. K. Lis]

The TTC has been closing stops NOT at traffic light controlled intersections, though there still are some, I think.

The TTC wants to eliminate closely spaced stops. For safety reasons, we want traffic lights at transit stops, since crosswalks tend to be ignored by motorists. Worse are the transit stops without any crosswalks or traffic signals.