Traffic lights - what about this instance

Bayum · 9 Nov 2015

Imagine a crossroads in front of you. There are two lines - both can be used to go straight ahead, the lane on the left can also be used to turn left and the one on the right can be used to turn right.

The traffic lights that control the junction have an arrow pointing left, as the usual RYG.

Now. If you are in the left lane, wanting to turn left and the green light comes on - are you able to turn left at this point?

There are no signs indicating that you should not turn left until the arrow is shown, but if you were to wait long enough, the green arrow indicating the left would illuminate.

What is the correct set of manoeuvres here?

RailUK Forums

ainsworth74 · 9 Nov 2015

I think the Highway Code should clear this up.

90019 · 9 Nov 2015

If it's a green light, you can go.
If it's a green arrow for either straight on or right, then you must wait.

PermitToTravel · 9 Nov 2015

Green arrow(s): you may go in the direction(s) indicated by the arrow(s) but no others
Green ball: you may go in any direction

Bletchleyite · 9 Nov 2015

The arrow usually indicates a clear flow i.e. you can make the turn with no conflicting traffic.

edwin_m · 9 Nov 2015

I don't think the OP's situation is possible, unless there is also a "straight on" arrow. Otherwise when the left filter arrow is lit, anyone wanting to turn left could be stuck in the left lane behind someone wanting to go ahead who is not allowed to proceed.

As far as I'm aware, if there is a filter arrow (or several arrows which only light simultaneously), there must be a dedicated lane on the approach for vehicles making that move.

Tetchytyke · 9 Nov 2015

edwin_m said:
As far as I'm aware, if there is a filter arrow (or several arrows which only light simultaneously), there must be a dedicated lane on the approach for vehicles making that move.

That would make sense, but nobody bothered to tell Newcastle City Council. There are several sets of lights around Gosforth and Jesmond where there's a filter arrow on a lane where you can go left or straight ahead. They've been like that for at as long as I can remember.

Phil. · 9 Nov 2015

Bayum said:
Imagine a crossroads in front of you. There are two lines - both can be used to go straight ahead, the lane on the left can also be used to turn left and the one on the right can be used to turn right.

The traffic lights that control the junction have an arrow pointing left, as the usual RYG.

Now. If you are in the left lane, wanting to turn left and the green light comes on - are you able to turn left at this point?

There are no signs indicating that you should not turn left until the arrow is shown, but if you were to wait long enough, the green arrow indicating the left would illuminate.

What is the correct set of manoeuvres here?

The correct manoeuvre is to turn left at the display of the green light if traffic movements permit. The traffic coming to-wards you and turning to their right takes precedence. Highway code rule 177.
That is all.

Bayum · 9 Nov 2015

edwin_m said:
I don't think the OP's situation is possible, unless there is also a "straight on" arrow. Otherwise when the left filter arrow is lit, anyone wanting to turn left could be stuck in the left lane behind someone wanting to go ahead who is not allowed to proceed.

As far as I'm aware, if there is a filter arrow (or several arrows which only light simultaneously), there must be a dedicated lane on the approach for vehicles making that move.

Unfortunately that's exactly what happens in Headingley.

It isn't so bad during the day and out of rush hour, but as soon as rush hour in either direction hits you will, guaranteed, have at least three drivers in a 15 minute period who decide against turning left even though a circular green is illuminated.

cb a1 · 9 Nov 2015

edwin_m said:
I don't think the OP's situation is possible, unless there is also a "straight on" arrow. Otherwise when the left filter arrow is lit, anyone wanting to turn left could be stuck in the left lane behind someone wanting to go ahead who is not allowed to proceed.

As far as I'm aware, if there is a filter arrow (or several arrows which only light simultaneously), there must be a dedicated lane on the approach for vehicles making that move.

It is very unusual to have a lane marked as ahead and left and for there to then be an 'ahead only' arrow which comes on in advance of a left-turn filter arrow.

However, this arrangement was in place at Tollcross in Edinburgh about 15 years ago for traffic on Earl Grey St going to Lauriston Place and Melville Drive. It would happen if there was a pedestrian call for the crossing across the Lauriston Place arm. It gave me so much scratching of my head when I was looking at the signal staging diagram that I went out and watched it in operation.

I would absolutely agree that it is not good practice to have this arrangement, but as far as I'm aware it's a 'should be a dedicated lane ...' rather than a 'must be a dedicated lane ...'.

Engineer · 9 Nov 2015

What if the green traffic light is flashing? On Network Rail you never get a flashing colour light signal on curved track.

EssexGonzo · 9 Nov 2015

A green light doesn't flash, as far as I'm aware.

Near me we have a T-junction set of lights. Approaching from the main stem of the "T" there is only one lane in total but there is a left filter light. More than one car wanting to turn right, hence waiting for the main round green light, and cars behind cannot take advantage of the left filter light.

Normally there is a filter lane but not always.

455driver · 9 Nov 2015

Engineer said:
On Network Rail you never get a flashing colour light signal on curved track.

Rubbish.

me123 · 9 Nov 2015

edwin_m said:
As far as I'm aware, if there is a filter arrow (or several arrows which only light simultaneously), there must be a dedicated lane on the approach for vehicles making that move.

This was also my understanding, until reading this forum of course. I've never known a situation in the UK (well, Scotland) where a filter light does not serve a dedicated lane for the direction(s) involved. I would find this situation quite confusing if I was to use the junction without any prior knowledge.

What I have seen in Glasgow is a slightly different approach that effectively gives the same results. Have a look at this street view image of a busy junction to the North of the City Centre. Traffic going to the left is signalled separately here and can turn left in situations where traffic going in other directions are instructed to stop. It was previously a give-way, which allowed a bit more freedom when turning left. As with the above layout, there is no guarantee that you can turn left (if there is a queue of traffic waiting to proceed), but it somehow appears to be more elegant in its approach. Of course, I suspect that space (or lack thereof) is the problem here - perhaps they want a better layout, but don't have the space to do it so this is a compromise.

To respond to the OP's question, I'd agree that a solid green light allows you to proceed, even if the left filter arrow is not illuminated. If there was to be any restriction to turning left (which is unlikely), then I'd expect a separate signal for left turning traffic to be red, and the green aspect to display arrows pointing both straight ahead and to the right.

As an aside, I've always wondered why the arrows only exist on the green aspect, and not on the red or yellow aspects in circumstances like this. It would make sense to me to do this, as I always feel wrong to drive through a red light with a green left-turn filter (particularly on an unfamiliar road) - even though what I'm doing is technically correct!

Oswyntail · 9 Nov 2015

(For those enjoying another thread) I wonder what Gearjammer would say. "Ignore the lights anyway because I know it's safe"?

GB · 9 Nov 2015

me123 said:
As an aside, I've always wondered why the arrows only exist on the green aspect, and not on the red or yellow aspects in circumstances like this. It would make sense to me to do this, as I always feel wrong to drive through a red light with a green left-turn filter (particularly on an unfamiliar road) - even though what I'm doing is technically correct!

All part and parcel of driving on the roads in my opinion. You quickly learn to ignore what doesn't apply to you and obey what does.

Bayum · 9 Nov 2015

So in this badly drawn diagram, if I'm wanting to drive into Leeds I can use either of the two far left lanes.

This is where the traffic light controls and I've drawn what the light looks like on the left.

The lights use their original functionality first and foremost, giving a circular, illuminated aspect.
A minute or so later, the arrow pointing left illuminates.

Depending who you're sat behind at this point determines whether you will have started moving or not.

I've always been under the impression that if there is a solid green and no signs saying otherwise (as there are on the opposite direction) then you were able to proceed under caution. As I said previously, in the opposite direction there is a sign saying right turning traffic must not proceed until the arrow is illuminated.

Confusing stuffs!

90019 · 9 Nov 2015

cb a1 said:
However, this arrangement was in place at Tollcross in Edinburgh about 15 years ago for traffic on Earl Grey St going to Lauriston Place and Melville Drive. It would happen if there was a pedestrian call for the crossing across the Lauriston Place arm.

That still exists, though it's rare to see anyone using the left hand lane to go straight on.

me123 · 9 Nov 2015

GB said:
All part and parcel of driving on the roads in my opinion. You quickly learn to ignore what doesn't apply to you and obey what does.

True, but it's still a bit off-putting at times when you don't know. I've just moved to Livingston and most of the traffic lights seem to have filters in one way or another, so I've just realised how odd it is (particularly driving home from a night shift!). Of course, doesn't take long to work it out and you'll never forget what happens, but when you're confronted with a new road layout and dozens of green arrows and red lights... it does make you think there might be a better way.

ac6000cw · 9 Nov 2015

me123 said:
As an aside, I've always wondered why the arrows only exist on the green aspect, and not on the red or yellow aspects in circumstances like this. It would make sense to me to do this, as I always feel wrong to drive through a red light with a green left-turn filter (particularly on an unfamiliar road) - even though what I'm doing is technically correct!

I agree - I think the 'full set of arrows' (using two side-by-side heads) that the Americans normally use in those situations is much better because it avoids the potential ambiguity with our way of doing things. On the other hand they allow 'right turn on red' by default (equivalent to treating a red as a 'give way' for left turns here) - never really been sure about that one, although I think allowing cyclists to do that is probably a good idea.

me123 · 9 Nov 2015

Bayum said:
The lights use their original functionality first and foremost, giving a circular, illuminated aspect.
A minute or so later, the arrow pointing left illuminates.

Depending who you're sat behind at this point determines whether you will have started moving or not.

I've always been under the impression that if there is a solid green and no signs saying otherwise (as there are on the opposite direction) then you were able to proceed under caution. As I said previously, in the opposite direction there is a sign saying right turning traffic must not proceed until the arrow is illuminated.

Confusing stuffs!

That's actually quite odd, and does make you think that you're not meant to turn left until the arrow light is illuminated. Which is different to most left arrows I've seen (which allow you to turn left before the other traffic can proceed in other directions). I'm assuming the traffic light looks something like this?

(Shamelessly stollen from the good people at CBRD)

Having said that, without a red aspect indicating not to proceed, or any signage advising likewise, you have no reason not to proceed as far as I'm aware. Most people who don't know the road (and many who do) would see a green light and proceed. In fact, if I was behind someone for a minute who wasn't moving in this situation, my horn would be getting activated quite frequently!

This seems to be backed up by the Highway Code, which states:

A GREEN ARROW may be provided in addition to the full green signal if movement in a certain direction is allowed before or after the full green phase. If the way is clear you may go but only in the direction shown by the arrow. You may do this whatever other lights may be showing. White light signals may be provided for trams

It implies to me that a full green signal would permit you to turn left in this instance.

Is there anything to the left that could require you to stop and wait for a minute (for example, a crossing?).
--- old post above --- --- new post below ---

ac6000cw said:
I agree - I think the 'full set of arrows' (using two side-by-side heads) that the Americans normally use in those situations is much better because it avoids the potential ambiguity with our way of doing things. On the other hand they allow 'right turn on red' by default (equivalent to treating a red as a 'give way' for left turns here) - never really been sure about that one, although I think allowing cyclists to do that is probably a good idea.

I'd advocate a steady amber aspect with a left turn arrow to state that "traffic can turn left with caution and must give way to oncoming traffic" in circumstances where it's considered safe to allow traffic to do so. I wouldn't support a blanket policy permitting left hand turns through red signals.

AM9 · 9 Nov 2015

me123 said:
.... without a red aspect indicating not to proceed, or any signage advising likewise, you have no reason not to proceed as far as I'm aware. Most people who don't know the road (and many who do) would see a green light and proceed. In fact, if I was behind someone for a minute who wasn't moving in this situation, my horn would be getting activated quite frequently!

This seems to be backed up by the Highway Code, which states:

It implies to me that a full green signal would permit you to turn left in this instance.

The issue here is similar to a turn-left lane that is too short. There are plenty that will be inaccessible when 2 or more cars are parked in the straight ahead lane. All that happens is that the lane becomes unblocked as the traffic gets a full green when those turning left get far enough forward to slip into the lane. If they can't clear the lane and turn left straight away, they only have to wait for the next cycle of lights to start. Maybe a bit frustrating, but no worse than sitting watching a whole green phase time out whilst a single right turn driver blocks the path ahead, (with or without a yellow box area).

me123 said:
I'd advocate a steady amber aspect with a left turn arrow to state that "traffic can turn left with caution and must give way to oncoming traffic" in circumstances where it's considered safe to allow traffic to do so. I wouldn't support a blanket policy permitting left hand turns through red signals.

There are enough road drivers here who see passing a red light as a claculated risk. Having a steady amber will be just like a green to them as it doesn't mean stop (does it?).

ralphchadkirk · 9 Nov 2015

Agree with the previous posters, you can turn left on a green light or a green filter arrow in that direction.

PermitToTravel · 9 Nov 2015

Phil. said:
The correct manoeuvre is to turn left at the display of the green light if traffic movements permit. The traffic coming to-wards you and turning to their right takes precedence. Highway code rule 177.
That is all.

No. Unless the junction is otherwise marked (the one in Bayum's drawing isn't), traffic turning right should give way to the oncoming traffic they turn across, regardless of the signals visible to either side.

If the right turning traffic has a green arrow pointing to the right, then there will usually not be oncoming traffic, though if there was for some reason (e.g. a driveway on the corner, after the stop line) then the right-turning traffic would still need to give way to it.

Crossover · 9 Nov 2015

I think a similar situation to what the OP describes can be seen here, on Dewsbury's Ring Road
https://www.google.co.uk/maps/@53.6...4g3XuXmNQkHqlecmRQ!2e0!7i13312!8i6656!6m1!1e1

Occasionally people will go in the right lane then get peeved off that people are stopped in front!
This particular junction has seen many arrangements of lights over the years, and at one point was a filter. How it is now is I'm sure how it used to be many years ago (with the filter phase coming in between)

As an aside, I find this junction near where I work a slight oddity:
https://www.google.co.uk/maps/@53.5...!2e0!5s20120701T000000!7i13312!8i6656!6m1!1e1

As the main phase goes to green, the right turn filter comes on simultaneously. The filter will let a few cars go and then go off. It doesn't come on at the end of the main phase and people just go as the lights change to amber as you would when the filter fails to fire for whatever reason. It all seems a bit backwards (but then again, it is Oldham :P)

Minilad · 9 Nov 2015

Engineer said:
What if the green traffic light is flashing? On Network Rail you never get a flashing colour light signal on curved track.

Oh rly?

PermitToTravel · 9 Nov 2015

Crossover said:
As the main phase goes to green, the right turn filter comes on simultaneously. The filter will let a few cars go and then go off. It doesn't come on at the end of the main phase and people just go as the lights change to amber as you would when the filter fails to fire for whatever reason. It all seems a bit backwards (but then again, it is Oldham :P)

That's very very common in the North West, and indeed pretty much the only way that right turn filters are implemented in Greater Manchester

Crossover · 10 Nov 2015

PermitToTravel said:
That's very very common in the North West, and indeed pretty much the only way that right turn filters are implemented in Greater Manchester

The junction back from it has a right turn filter that works in the conventional way!

PermitToTravel · 10 Nov 2015

The unusual way, from the point of view of the locals :P

radamfi · 10 Nov 2015

In some countries, it is not allowed to have a green signal for a right-turn (or left-turn where they drive on the right) unless the traffic coming from the opposite direction has a red light. There is no waiting in the middle of the road until the way is clear.

Traffic lights - what about this instance

Established Member

RailUK Forums

Forum Staff

Established Member

Established Member

Veteran Member

Veteran Member

Veteran Member

Established Member

Established Member

Member

Member

Member

Veteran Member

Established Member

Established Member

Established Member

Established Member

Established Member

Established Member

Established Member

Established Member

Veteran Member

Established Member

Established Member

Established Member

Established Member

Established Member

Established Member

Established Member

Established Member