How is yellow trap / clearance handled in other countries outside the US?

[fwydriver405]

I was watching a few videos on YouTube from the UK from Ashley Neal recently, and in one of those videos, I noticed a classic case of single-lag yellow trap with "yield (or give way) on green" Protected/Permissive Left (Right in this case since UK drives on left) Turn signals, with a driver getting "trapped" in the intersection when the permissive-only approach without any protected (or filter) arrows changed to yellow (amber) to give the cammer's direction a protected green right turn arrow (Video Link: Skip to 3:25).

Also in that video above, you'll also notice that the green arrow goes out with no yellow arrow clearance. Since this was a lagging left turn with no recall (next phase serves cross traffic), the yellow arrow is not necessary since thru and left turning traffic is also getting a yellow as well. However, in a different video by someone else below, with a LEADING right turn, when the LEADING right turn ends, there is just a blind clearance between the end of the protected turn and when oncoming traffic is released. (Video Link: Skip to 0:45)

How is yellow trap handled in other countries outside of the US, alongside any kind of yellow / amber clearance for turning traffic? Most European countries just have the green arrow segment only (not bimodal) for left/right turns. Some Asian countries are the same way as well, but Japan for example, uses the circular yellow to extinguish turn arrows. (Yellow arrows in Japan are used for transit vehicles, from what I was told)

[kphoger]

In Mexico, I believe the law is that, if a signal has left-turn arrows, then it is protected-only.  That is to say, "left turn on green arrow only" is the case everywhere.  I haven't actually looked up to see if that's true, but that's what I was told by a car rental agent in Nayarit back in 2006, and it jived with what I saw in practice.

At any rate, split phasing is used a lot in Mexico, with each direction getting its own phase.  I know other signal phasing exists in Mexico, but I haven't had enough experience with them to say anything with confidence.

[andrepoiy]

In Ontario, the left turn arrow only comes on after the cross-traffic goes, and thus there is no opportunity for a yellow trap. I still haven't seen any time where the left turn arrow comes on mid-phase despite living here my whole life.

[ran4sh]

In Ontario, the left turn arrow only comes on after the cross-traffic goes, and thus there is no opportunity for a yellow trap. I still haven't seen any time where the left turn arrow comes on mid-phase despite living here my whole life.

So does Ontario not allow phase skipping on its traffic signals? An example would be, traffic is waiting on the main road to turn left onto the cross road, but there is no traffic waiting on the cross road; with phase skip the cross road phases are skipped and the signal advances to the next phase which is the left turns.

That would technically not be "mid-phase", but to a driver it would be indistinguishable from that.

[fwydriver405]

In Ontario, the left turn arrow only comes on after the cross-traffic goes, and thus there is no opportunity for a yellow trap. I still haven't seen any time where the left turn arrow comes on mid-phase despite living here my whole life.

So does Ontario not allow phase skipping on its traffic signals? An example would be, traffic is waiting on the main road to turn left onto the cross road, but there is no traffic waiting on the cross road; with phase skip the cross road phases are skipped and the signal advances to the next phase which is the left turns.

That would technically not be "mid-phase", but to a driver it would be indistinguishable from that.

This is mostly for yield on green, leading left setups, but could be a possibility that:

1. Signals in Ontario go all red before re-serving the main road left turn with a protected left green arrow (this happens at one intersection in my city)
2. Signals in Ontario place a false call to the side street - even with no cars, it will give a green to the side road before serving main road left turns with a protected green left arrow (Seen this at one intersection in Cape Cod)
3. Anti-backup phasing is in place (mostly for yield on green, leading permissive left setups)

(See here for more info)

[andrepoiy]

The thing is, I have never seen a situation where there was a very long line of cars in the left turn lane but no cars in the cross traffic. There's always someone in the cross road, but in cases where there isn't (like late night), there also isn't a long line at the left turn.

So yeah, that's just my observations. It seems like a yellow trap situation is so rare that despite living here for years, I still have not seen one, and I guess Ontario also deems it rare enough to just keep everything as is.

[ran4sh]

The thing is, I have never seen a situation where there was a very long line of cars in the left turn lane but no cars in the cross traffic. There's always someone in the cross road, but in cases where there isn't (like late night), there also isn't a long line at the left turn.

So yeah, that's just my observations. It seems like a yellow trap situation is so rare that despite living here for years, I still have not seen one, and I guess Ontario also deems it rare enough to just keep everything as is.

A very long line? Does it take more than one car to get a protected left? (Everywhere I have seen has the detector at the front of the lane so it only takes 1 car to activate it, although I have heard of permissive turn setups with the detector farther back so that it only detects if there is a line of cars.)

[andrepoiy]

The thing is, I have never seen a situation where there was a very long line of cars in the left turn lane but no cars in the cross traffic. There's always someone in the cross road, but in cases where there isn't (like late night), there also isn't a long line at the left turn.

So yeah, that's just my observations. It seems like a yellow trap situation is so rare that despite living here for years, I still have not seen one, and I guess Ontario also deems it rare enough to just keep everything as is.

A very long line? Does it take more than one car to get a protected left? (Everywhere I have seen has the detector at the front of the lane so it only takes 1 car to activate it, although I have heard of permissive turn setups with the detector farther back so that it only detects if there is a line of cars.)

It absolutely does take more than one car to get a protected left here.

[mrsman]

The thing is, I have never seen a situation where there was a very long line of cars in the left turn lane but no cars in the cross traffic. There's always someone in the cross road, but in cases where there isn't (like late night), there also isn't a long line at the left turn.

So yeah, that's just my observations. It seems like a yellow trap situation is so rare that despite living here for years, I still have not seen one, and I guess Ontario also deems it rare enough to just keep everything as is.

A very long line? Does it take more than one car to get a protected left? (Everywhere I have seen has the detector at the front of the lane so it only takes 1 car to activate it, although I have heard of permissive turn setups with the detector farther back so that it only detects if there is a line of cars.)

It absolutely does take more than one car to get a protected left here.

That is the standard in Los Angeles as well.  Most of the permissive left arrows require at least 3 cars in the left turn lane, before the arrow is given.  There is a presumption that 2 or fewer cars do not need the arrow protection and would simply be able to go during a gap in traffic or at the end of the cycle during yellow.

Here is La Cienega just south of Olympic.  notice how far these sensors are from the intersection.  The left arrow will only come on if there are a significant number of cars in the left turn lane.

https://www.google.com/maps/@34.0590677,-118.3762572,3a,75y,60.33h,87.92t/data=!3m6!1e1!3m4!1sCoQH6ge_CkjQFLOHSFfbXQ!2e0!7i16384!8i8192

[Jet380]

Here in Western Australia, signals are almost never set up in a way that would enable a yellow trap. Protected-permissive signals will generally only have a leading green arrow. Lagging arrows are sometimes used at T junctions or where there is no opposing right turn, but otherwise, if a lagging arrow is to be used, it will be fully protected.

I say 'almost never' because I have spotted one intersection with a yellow trap due to railway pre-emption. If a train approaches while Hamilton Street has the green, the phase for traffic coming from the south west will end early, giving a green arrow for traffic coming from the north east to clear the crossing.

[ran4sh]

I think that if I were to actually encounter a setup where I could tell that the detector is back from the stop line, I could just wait there on a red light to get the arrow (instead of going all the way forward to the line).

[andrepoiy]

I think that if I were to actually encounter a setup where I could tell that the detector is back from the stop line, I could just wait there on a red light to get the arrow (instead of going all the way forward to the line).

Yes, I see someone occasionally doing that, but it's actually pretty rare

[riiga]

No such thing here as far as I know. The only permissive left turn setups that I know of use a green arrow for the protected phase at the end allowing traffic to clear the intersection safely. Such an arrow must only be lit up together with the main round green and also means traffic in the opposite direction gets red.

In addition, at speeds over 50 km/h (30 mph) permissive turns regulated by signals are not allowed, only protected turns are, so the only cases where it can possibly happen is in low-speed environments where I'm yet to see such a setup that would cause a yellow trap. There are to my knowledge also no or very few dual permissive left turns in Sweden.

Below for reference is some (translated) regulation I've come across.

[ran4sh]

There are to my knowledge also no or very few dual permissive left turns in Sweden.

Most US states also ban dual permissive left turns, it's only a few places where it's allowed (and a few members of this forum that think it should be allowed more).

[Mr Kite]

I was watching a few videos on YouTube from the UK from Ashley Neal recently, and in one of those videos, I noticed a classic case of single-lag yellow trap with "yield (or give way) on green" Protected/Permissive Left (Right in this case since UK drives on left) Turn signals, with a driver getting "trapped" in the intersection when the permissive-only approach without any protected (or filter) arrows changed to yellow (amber) to give the cammer's direction a protected green right turn arrow (Video Link: Skip to 3:25).

Also in that video above, you'll also notice that the green arrow goes out with no yellow arrow clearance. Since this was a lagging left turn with no recall (next phase serves cross traffic), the yellow arrow is not necessary since thru and left turning traffic is also getting a yellow as well. However, in a different video by someone else below, with a LEADING right turn, when the LEADING right turn ends, there is just a blind clearance between the end of the protected turn and when oncoming traffic is released. (Video Link: Skip to 0:45)

How is yellow trap handled in other countries outside of the US, alongside any kind of yellow / amber clearance for turning traffic? Most European countries just have the green arrow segment only (not bimodal) for left/right turns. Some Asian countries are the same way as well, but Japan for example, uses the circular yellow to extinguish turn arrows. (Yellow arrows in Japan are used for transit vehicles, from what I was told)

Hi there. Those lights in your first example are in my hometown, here...

https://www.google.com/maps/@53.4365103,-2.9331579,3a,75y,34.81h,100.99t/data=!3m6!1e1!3m4!1ssh9O9ClR-eMqpEtaqp9ukQ!2e0!7i16384!8i8192

Whilst it's standard in the UK for there to be signals both at the stop line and the far side of the intersection, where there's a lagging left turn, the direction that gets the early cut off usual only has signals before the intersection. Here's what the opposite approach of the same intersection looks like...

https://www.google.com/maps/@53.4370025,-2.9326157,3a,75y,198.56h,92.21t/data=!3m6!1e1!3m4!1sMVMitrYCKk9JDi3LU1SdOg!2e0!7i16384!8i8192

As you can see, there are a couple of signals at the stop line, then a couple just a bit further back, enough so vehicles at the front of the queue can see the status of the signals but still before the intersection. If waiting in the intersection to turn right, you can see no signals and so are concentrated on waiting for the oncoming traffic to stop.

T-junctions often have signals on the far side anyway, as amber trap is perceived not to be such an issue such as here...

https://www.google.com/maps/@53.4225143,-2.9407943,3a,75y,73.97h,90t/data=!3m7!1e1!3m5!1s3h9I4TFEz4uc4qRJZ2OrNw!2e0!6shttps:%2F%2Fstreetviewpixels-pa.googleapis.com%2Fv1%2Fthumbnail%3Fpanoid%3D3h9I4TFEz4uc4qRJZ2OrNw%26cb_client%3Dmaps_sv.tactile.gps%26w%3D203%26h%3D100%26yaw%3D64.26332%26pitch%3D0%26thumbfov%3D100!7i16384!8i8192

Notice, though, that there is no ban on U-turns here and so amber trap can actually still occur.

As for protected right at the beginning, yes, the arrow comes on with the green ball and then just disappears after a few moments. Northern Ireland is different, as they have an additional amber ball aspect which terminates the arrow (something they got from the republic). This side of the Irish Sea, they're depreciated: only really popular in Northern places such as Liverpool & Manchester, much rarer in the south and outright banned in London. The objection to them seems to be the inbetween bit where the arrow goes off and oncoming traffic is released, which they consider not safe.

Hope this information helps.

[SkyPesos]

For mainland China, I've been in 7 provinces along the east coast, and have never seen a protected-permissive signal in any of those places. Not sure if it's a thing in other provinces in the central or western part of the country. It's either permissive only (green bulb) on less busy roads, or protected only (green arrow) on busier roads. Not sure why this is the case, as protected-permissive signals are somewhat common in neighboring Japan and Taiwan; maybe it's because drivers in the mainland are generally terrible at yielding to pedestrians in my experience?

[andrepoiy]

For mainland China, I've been in 7 provinces along the east coast, and have never seen a protected-permissive signal in any of those places. Not sure if it's a thing in other provinces in the central or western part of the country. It's either permissive only (green bulb) on less busy roads, or protected only (green arrow) on busier roads. Not sure why this is the case, as protected-permissive signals are somewhat common in neighboring Japan and Taiwan; maybe it's because drivers in the mainland are generally terrible at yielding to pedestrians in my experience?

I didn't pay much attention when I was in Shanghai to signal configurations, but I did notice that cars who were on a green bulb and wanted to turn left, don't yield and instead go first... I don't remember if that was an isolated case though, it's been a while

[jakeroot]

There are to my knowledge also no or very few dual permissive left turns in Sweden.

Most US states also ban dual permissive left turns, it's only a few places where it's allowed (and a few members of this forum that think it should be allowed more).

Only a few states don't seem to have rules against it, but most cities (and counties) don't have any actual ban that I've seen. Still, many cities follow state rules, so they're relatively rare (if not very common in the few states that permit it/apparently encourage it).

I think that if I were to actually encounter a setup where I could tell that the detector is back from the stop line, I could just wait there on a red light to get the arrow (instead of going all the way forward to the line).

You could but there is no operational advantage in doing so. In fact, it's actually worse for traffic since you then introduce a protected phase, taking time away from through traffic. As opposed to turning in a gap or during the all-red phase, which does not detract from the capacity of through traffic.

[SkyPesos]

For mainland China, I've been in 7 provinces along the east coast, and have never seen a protected-permissive signal in any of those places. Not sure if it's a thing in other provinces in the central or western part of the country. It's either permissive only (green bulb) on less busy roads, or protected only (green arrow) on busier roads. Not sure why this is the case, as protected-permissive signals are somewhat common in neighboring Japan and Taiwan; maybe it's because drivers in the mainland are generally terrible at yielding to pedestrians in my experience?

I didn't pay much attention when I was in Shanghai to signal configurations, but I did notice that cars who were on a green bulb and wanted to turn left, don't yield and instead go first... I don't remember if that was an isolated case though, it's been a while

Assuming you're referring to not yielding to pedestrians, it's probably not an isolated case. I see a lot of aggressive drivers in China; some of them drive in downtowns like there's no pedestrians around. No wonder why a lot of major arterials in various Chinese cities are getting bridge or tunnel pedestrian crossings, and removing at grade crossings.

[andrepoiy]

No, it was just not yielding to oncoming traffic. Pretty much just gunning the left turn before oncoming traffic makes it over.

[fwydriver405]

No, it was just not yielding to oncoming traffic. Pretty much just gunning the left turn before oncoming traffic makes it over.

Similar to a Boston left (other regional variations exist as well, e.g. Pittsburgh left)?

[spooky]

No, it was just not yielding to oncoming traffic. Pretty much just gunning the left turn before oncoming traffic makes it over.

Similar to a Boston left (other regional variations exist as well, e.g. Pittsburgh left)?

Ah, the Boston rule of the road: The right-of-way belongs to he who most aggressively pursues it.