Tag:traffic_calming=island

[Yog_Sot]

there is a need for a clear decission when a traffic calming island is actually, a tag:traffic_calming=island

• traffic_calming=island is tagged when there is a physical island separating lanes of traffic that calms it by physically prohibiting eg. overtaking and thus helping to maintain safe driving practices
• traffic_calming=island is tagged only when it separates lanes of traffic in such a way it requires slowing down below normally expected speed

Reasoning:

A traffic calming by definition is is used to calm down the traffic, physically or visually prohibit dangerous driving. That’s how people understand it across the world. Question is if this OSM tagging should be restricted only to some of those traffic calming islands

• Skillfull drivers may ignore some traffic calmings and go above allowed speed limit anyway or ignore slowing down before traffic calmed pedestrian crossing with a claim that speed limit was not restricted by a traffic sign,
• but other drivers may slow down because they will spot the calming features.

So, there are traffic calmings that actually physically restrict speed even to very skilled drivers, but there are also those, which by creating the calming expectation, make drivers to slow down.

Thats why we should decide if we use the tag how it is actually understood worldwide
– as a traffic calming for calming down the traffic
OR – as a feature that slows down the traffic only
(calmed down traffic is expected to be slower, but we all know from experience that intention does not equal reality and original 2008 proposal might have impreciselly assumed both terms to be same thing)

Calming the traffic is the logical choice for me and makes a decission on tagging simple, because everytime there is a physical lanes separating island, you tag it so.
The other is harder to decide, arbitrary decission has to be made and different people may come to a different conclussion depending on their driving style and skill

Rendering
Additionally rendering the islands comes easy, because all physical islands are tagged so and can be rendered for people to see on maps, which IMO is much better than separating the highway into two different one-way highways just because there is 4m² kerbed traffic island with some traffic excluded painted markings

Routing
Opposers argue, that routings give a penalty to a highway with a traffic calming and may route drivers elsewhere to a road that has thinner lanes, but not divided by traffic islands anywhere.
IMO that is fault of those routings that they did not detect those issue and they have not taken the effort to map width of the lanes, lane markings and other details that their routings can use.

I welcome everyone to a discussion.
Hopefully we can have at least 75% votes to reach any consensus on this comeing back issue.

[Mateusz_Konieczny]

can you give photo example of case or cases where poll question would matter?

[Yog_Sot]

kerbed island with signs/on a curve
If you disagree, you pick the option that traffic_calming=island -must require slowing down and not option with -helping to maintain safe driving practices

[Mateusz_Konieczny]

are you claiming that

does not require slowing down?

[Yog_Sot]

you are expected to slow down, but the tire marks clearly show actual geometry and as experienced driver you can surely know that speed reduction does not happen to everyone with this geometry.

Anyway, slowing down is vehicle dependent.
If you’re a truck or a motorcycle, gues i don’t have to explain?
Maybe you need additional tagging if a traffic island is actually slowing down separatelly different kinds of vehicles?
And maybe different islands have got multiple functions? I’m not trying to list those right now. But pointing out what a traffic calming island actually is along with its general function.

That’s why this tag should be about if it’s calming traffic and not that you have to go slower, which i did explain in the reasoning.

Try building up something useful on top of that.

[Mateusz_Konieczny]

@Yog_Sot

tire marks clearly show actual geometry

and they are not straight, so some traffic calming was achieved

[Peter_Elderson]

Any complication achieves traffic calming, foot off the gas pedal and ready for breaking. In this case, I think the complication is not the island per se, but the intersection, the sign on the pole and the crossing. If it were just the painted island and the slight bend, I don’t think it would calm anything.

[Hendrik_Helsper]

I would tag traffic_calming=island only when a: at least one lane deviates enough to necessitate significant steering and or slowing down (for the average driver) to safely pass it. or b: the lane(s) narrow significantly because of the island and thus indicate a slower design speed at that location. Simply preventing overtaking can’t be a criterium since that can also be achieved by any linear physical barrier - and not every barrier is traffic_calming.

So following that guideline:

Picture 1: no traffic_calming because there is neither narrowing nor deviation of the driving lanes. The only deviation is because of the turning lane, not the island. so the island doesn’t do anything here.
picture 2: probably traffic_calming but debatable. if it is in a low speed zone it would probably not cause any additional calming of traffic.
picture 3 and 4: definetly traffic_calming (especially 4)
picture 5: probably also traffic_calming although the picture doesn’t show a lot of context.

[Yog_Sot]

@Hendrik_Helsper

traffic_calming=island only when a: at least one lane deviates enough to necessitate significant steering and or slowing down

@Yog_Sot

Anyway, slowing down is vehicle dependent.
If you’re a truck or a motorcycle, gues i don’t have to explain?
Maybe you need additional tagging if a traffic island is actually slowing down separatelly different kinds of vehicles?

@Hendrik_Helsper

Simply preventing overtaking can’t be a criterium

@Yog_Sot

maybe different islands have got multiple functions?
…
That’s why this tag should be about if it’s calming traffic and not that you have to go slower, which i did explain in the reasoning.

@Yog_Sot

we should decide if we use the tag how it is actually understood worldwide
– as a traffic calming for calming down the traffic

I assume you insist that calming traffic has to be always about mandatory speed reduction but at the same time you’re undecided in every case and your opinion is not aligned with other opinions if avarage driver have to slow down

@Yog_Sot

everytime there is a physical lanes separating island, you tag it so.
The other is harder to decide, arbitrary decission has to be made and different people may come to a different conclussion depending on their driving style and skill

[flohoff]

I fail to see an issue you are trying to fix.

Do you suggest too many islands are actually not a traffic_calming and cause to much of a router penalty?

In the area i am mostly working at we have come to the agreement that if its not for pedestrian crossing (Which is obvious) its a traffic calming.

And i fail to follow your reasoning that calming is always about speed. Calming is not just about speed - its about seperation e.g. in intersections or roundabouts.

Flo

[Yog_Sot]

I gues a language barrier

@flohoff

Do you suggest too many islands are actually not a traffic_calming and cause to much of a router penalty?

Some people claim it and thus refuse to tag traffic islands, because in their opinion routers dont pick a wide primary road with traffic calmings, but rather pick a residential one where width is not mapped. I clearly pointed out the root issue tho.

@flohoff

And i fail to follow your reasoning that calming is always about speed. Calming is not just about speed - its about seperation e.g. in intersections or roundabouts.

Calming is not just about speed

But i have given an option to vote for those that disagree

[Hendrik_Helsper]

@Yog_Sot

Anyway, slowing down is vehicle dependent

I would specifically exclude large lorries from this requirement since any bends might be enough for them to need to slow down. If it effects motorcars I would count it as traffic_calming. Anything that affects single-track vehicles also affects double-track vehicles. So it’s mainly about motorcars.

@Yog_Sot

maybe different islands have got multiple functions?
…
That’s why this tag should be about if it’s calming traffic and not that you have to go slower, which i did explain in the reasoning.

Well, I do not believe that simply preventing overtaking is traffic calming.

Traffic calming to me is either: 1 supposed to lower traffic speeds, 2 supposed to lower vehicle throughput. But maybe you disagree and that’s ok.

@Yog_Sot

I assume you insist that calming traffic has to be always about mandatory speed reduction

No. I never claimed that anything was mandatory. Traffic calming can also just be paint. (see this example).

I guess I would be ok with labeling all the islands except the first one traffic_calming. But if the majority disagrees I don’t really mind following suit, although then I would ask whether then guardrails and fog lines wouldn’t also have to be called traffic calming elements.

[Peter_Elderson]

If it’s mainly for separation or intersection layout, I tag traffic islands as area:highway=traffic_island. E.g. roundabout flares. If there is a significant kerb (e.g. roundabout apron), I map the kerb.

[Yog_Sot]

@Hendrik_Helsper

I would specifically exclude large lorries from this requirement

So lorry drivers are not supposed to know they will have to be carefull at this road…
because we are not supposed to map traffic islands that have small effect on passanger cars?

@Yog_Sot

Maybe you need additional tagging if a traffic island is actually slowing down separatelly different kinds of vehicles?

You did not reply on that tho, which does solve the issue tbh, but yeah, not right this instant, but only when people implement such tagging in distant future

If you have never claimed that anything was mandatory. You can always change your vote

@Hendrik_Helsper

Traffic calming can also just be paint. (see this example).

Yes, it is, but it is not an island.
There are traffic islands that are paint only and i do agree those should be mapped as well, but there is already an issue with kerbed islands, that some people refuse to accept as traffic calming in OSM, even tho those are by worldwide definition traffic calming road design features that are helping to maintain safe driving practices.

@Peter_Elderson

I tag traffic islands as area:highway=traffic_island.

Yeah, we have got all kinds of area:highway and none are ever used in any commetcial maps and routers i see.
Using those tagged areas is whole another topic and in his vote it’s about tagging traffic islands as nodes or possibly ways. And i would love to avoid going into One feature, one OSM element - OpenStreetMap Wiki rules, because yeah, very scetchy, especially when we get crossings into equasion.

[IreuN (Michał)]

@Yog_Sot

Calming is not just about speed

traffic_calming=* is just about speed. traffic_calming=* relays function information, not geometrical information.
It is an approved key and no value should contradict to what has been already approved in the key.
ref: Proposal:Traffic Calming - OpenStreetMap Wiki

You’re trying to pour Wikipedia definition into approved proposal in OSM. Wikipedia’s “traffic calming” (and also real world traffic calming meaning) does not need to (and indeed does not) go along with OSM’s definition of traffic_calming.

@Yog_Sot

Routing
Opposers argue, that routings give a penalty to a highway with a traffic calming and may route drivers elsewhere to a road that has thinner lanes, but not divided by traffic islands anywhere.
IMO that is fault of those routings that they did not detect those issue and they have not taken the effort to map width of the lanes, lane markings and other details that their routings can use.

Routers are rightfully applying penalty for traffic_calming just like it is said in the approved proposal above.

Whole point of traffic_calming=* key was:

Having just been routed by my SatNav down a road with half a dozen speed bumps even though it is marked on maps as a tertiary route, I was struck by the need to have this information in the map data even if it is not displayed, to that these ways can be avoided. – Batchoy 16:21, 12 December 2006 (UTC)

It was made to add a penalty to (and to avoid) speed bumps, humps, chicanes etc. - all of these have the FUNCTION of slowing down cars.

What you are actually trying to do is make the tag skunked, and you’ve already been said that before in polish discord. Your solution to this problem is (as an exception to all of other traffic_calming=* features) to just ignore traffic_calming=island by routers, since it would lost it’s meaning.

I’ve also already showed you what real traffic_calming=island looks like:

Point being - not every traffic island should be tagged with traffic_calming key.

This has already been discussed for example here:

What's the traffic_calming=island area?

[traffic] Hi, I have a micromapping question. If I want to draw a traffic_calming=island area, should I map the painted area or the “physical” area? en.wikipedia says: " A traffic island is a solid or painted object in a road that channels traffic", but since sometimes we have other conventions I prefere to ask. Also we could update the OSM wiki to make it clear. In case mapping the painted area is the correct option, is there a way to map the physical one as well? I was thinking of barrier=k…

Does crossing:island=yes imply traffic_calming=island?

So, not all traffic islands are pedestrian refuges, i.e. part of a crossing: [image] But, as far as I can imagine, the other way around, all pedestrian refuges are traffic islands, right? Or can anyone think of a case where this is indeed not the case? Otherwise I would add a hint in the wiki for data consumers that they should also look at crossing:island=yes (and the deprecated crossing=island since its usage is still in the thousands). And finally, if any pedestrian refuge is anyway also…

Traffic islands

Hello fellow mappers! I have been mapping traffic islands for some time now and while most of the time it is pretty straightforward thing to do, I still managed to find myself in few places scratching my head. I need a little help on how it should be done in few specific situations and prehaps even standardize it for the future. I have been mapping traffic islands as an area with few occasions as a point. Traffic island wiki: Wiki When there is a highway that is pretty wide and there has been…

Also - don’t you think a ‘poll’ should be made after discussion, not before? Until now I’ve seen no posts here that would support 1st option

[Yog_Sot]

@IreuN

traffic_calming=* is just about speed.

So many people think it’s actually about calming the traffic and thus helping to maintain safe driving practices.

But yeah, you go on with denying it.
Sure you can discuss anything, but maybe stop implying you have been trying to explain anything, while at the same time you ignore that

• traffic island may actually slow down only lorries and because you want to map for passanger cars only, you refuse to map this useful info for truck drivers.
• when there is very long traffic island, your routings ignore that and likely does the same thing with crossings through traffic islands, which also then you forbid to map
• you advocate for use of area:highway but that is only because your routings completely ignore it and so you’re all fine
• you blame me for making tag skunked, but it is you that does not understand that calming traffic down is not solely about speed.
• actually intersections with traffic islands are used to make traffic go smoother, so often even faster than otherwise… but you insist that calming traffic down is only about making it slower

@IreuN

Also - don’t you think a ‘poll’ should be made after discussion, not before? Until now I’ve seen no posts here that would support 1st option

I suppose you’d like that i didnt even try to discuss anything, as you implied that everyone think like you, which turned out not true.

[IreuN (Michał)]

So many people think it’s actually about calming the traffic

So I guess so many people have not red the approved definition of traffic_calming Maybe those people were influenced by over 3 years of iD lumping traffic_calming=island as misleading “Traffic island” up until the point when I’ve brought that up to iD devs and fixed it?

• when there is very long traffic island, your routings ignore that and likely does the same thing with crossings through traffic islands, which also then you forbid to map

I have no idea what you are trying to express here

you advocate for use of area:highway but that is only because your routings completely ignore it and so you’re all fine

Sure, why would you not use it? Why are you insisting to add traffic_calming for features that do not go along with it’s OSM approved definition?

• it is you that does not understand that calming traffic down is not solely about speed.
• actually intersections with traffic islands are used to make traffic go smoother, so often even faster than otherwise… but you insist that calming traffic down is only about making it slower

It does not matter - you are trying to pass a 75% vote to contradict an APPROVED proposal (approved since 2008) for just one specific value. That is specifically what skunking means:

A data consumer cannot easily predict which definition of a tag was used when a mapper added it to a feature. Even if the data consumer can analyze the feature’s history, the intent can become obscured when the feature is split or merged. If the data consumer cannot come up with a heuristic to distinguish the two definitions, it may have to ignore the tag entirely.

Consumers would not be able to know if such feature goes along with approved traffic_calming=* meaning, or with an exception of which would became traffic_calming=island.

• actually intersections with traffic islands are used to make traffic go smoother, so often even faster than otherwise… but you insist that calming traffic down is only about making it slower

As I’ve said - not every traffic island should be tagged with traffic_calming..

I suppose you’d like that i didnt even try to discuss anything, as you implied that everyone think like you, which turned out not true.

I have never said that, and also I’ve just given you 3x links to threads that contain such arguments - I’m well aware of them.

And actually it’s you that have said it XD:

@Yog_Sot

To my suprise everyone proritise “safe driving practices” over “requiring to slow down” and IMO that makes all islands that separate traffic lanes to be tagged as island with a traffic_calming tag

everyone being 60/40
…

IMO that is fault of those routings that they did not detect those issue and they have not taken the effort to map width of the lanes, lane markings and other details that their routings can use.

Routers are not there to map anything, they are data-consumers.

Also this was was discussed back in 2020 in the wiki: Talk:Tag:traffic calming=island - OpenStreetMap Wiki?

[JeroenvanderGun (dr.ir. Jeroen van der Gun)]

Anything that physically prohibits overtaking, by definition slows down the traffic that would overtake otherwise. Aggressive drivers that like to overtake by definition slow down below their normally expected speed. So the proposed more restrictive interpretation of traffic_calming=* doesn’t make sense to me. Traffic calming installations are primarily targeted at aggressive drivers. Calm drivers obeying the speed limit may not need to slow down at all. This also applies to other installations like speed bumps.

In presence of sufficiently long central reservations you can tag dual_carriageway=yes instead of traffic_calming=island. If you want to tag traffic island areas for 2D map rendering, then you can use area:highway=traffic_island in any case.

[Hendrik_Helsper]

A solid center line prohibits overtaking aswell. Would you consider that to be traffic calming infrastructure?

[IreuN (Michał)]

Again - traffic_calming=* has nothing to do with discouraging overtaking - traffic_calming=* was created for routing algorithms to allow avoidance of obstacles along your route. It was it’s reason, it was it’s approved proposal and it is it’s OSM’s definition.

Rationale behind proposal was:

Having just been routed by my SatNav down a road with half a dozen speed bumps even though it is marked on maps as a tertiary route, I was struck by the need to have this information in the map data even if it is not displayed, so that these ways can be avoided. – Batchoy 16:21, 12 December 2006 (UTC)

Approved proposal is as follows:

to tag road features that are designed to slow down traffic in residential areas

OSM definition (before 31 Aug 2013 ref)

The traffic_calming=* tag can be used to identify roads or points along a road with speed bumps or other devices to slow motorised traffic.

OSM definition (since 31 Aug 2013 ref)

Traffic calming consists of engineering and other measures put in place on roads for slowing down or reducing motor-vehicle traffic as well as to improve safety for pedestrians and cyclists.

^^ I don’t quite get the “or reducing motor-vehicle traffic” part - maybe it’s connected to the ‘avoidance’ of roads with many such features?

Also in response to ''Anything that physically prohibits overtaking, by definition slows down the traffic that would overtake otherwise":

Some, like proper urban planning are subjective and not mapped at all in OpenStreetMap.

^^ from Key:traffic_calming - OpenStreetMap Wiki