|Traffic signs give instructions or provide information to road users.|
|Used on these elements|
|Status: De facto|
|Tools for this tag|
The traffic_sign=* tag is used to map traffic signs such as city-limit signs or any other traffic signs.
Traffic signs give instructions or provide information to road users. Some signs are only relevant at the place where they're mounted (like e.g. a stop sign - called point-related signs from now on), while others affect a section of the road (like e.g. a "no overtaking" sign - called section-related signs).
How to map
Point-related signs can be mapped by tagging a node, while section-related signs can be mapped by tagging a way (or area). You may also map a section-related sign by tagging it as a node if you only know where the section begins or if you just want to explicitly specify its physical location. Keep in mind that additional tagging is necessary to indicate the end of the section in this case.
The implications of a traffic sign should always be tagged on the concerned section of the road itself as well. When mapping a speed limit sign for example: always add a maxspeed=* and a source:maxspeed=sign tag to the road itself.
It is possible to use a node which is part of a way, or to create a separate node beside the road. Both methods are used in practice.
As part of a way
Create a new node within the relevant way next to the sign. This method allows software algorithms which operate on ways (like e.g. routing algorithms) to consider the sign, but makes it impossible to know the exact position of the sign. A renderer can at best assume that the sign is located somewhere next to the road.
You can use traffic_sign:forward=* to specify that this sign affects vehicles moving in the same direction as the OSM way. The opposite direction can be tagged with traffic_sign:backward=*. Formerly the direction=* key has also been used to describe the affected direction. But its common meaning has changed to Relative to Geographic North.
Only the affected direction can only be specified by using nodes which are part of exactly one way . Avoid junction nodes and nodes between two ways as well (where they have been split, but are connected by a node). If in doubt, better simply insert a new node into the way instead of using an existing one.
As a separate node
Create a separate node beside the road at the position of the actual sign. This allows to map the exact physical position of the sign, but it is impossible to reliably deduce the affected road or travel direction in this case. Software algorithms which operate on ways will thus generally not be able to consider the traffic sign, but only the tags of the way instead.
On a way or area
When tagged on a way or an area, the traffic_sign=* tag describes the traffic sign(s) that apply to that way or area. The tag is not meant to mark the actual position of the sign in this case, but the affected way or area instead. It should however be assumed that the physical location of the sign is at the beginning and / or the end of the affected section (but note that the affected section may be comprised of multiple ways within OSM).
You may use traffic_sign:forward=* to specify that this particular sign affects vehicles moving in the same direction as the way, or traffic_sign:backward=* to specify that the opposite direction is affected.
It is common to use both human-readable values (like city_limit) as well as national traffic sign IDs (like DE:310).
Multiple signs can be tagged by using different separators. Traffic signs which are unrelated to each other (like e.g. speed limit and no parking) are separated by semicolon
;. Related signs (like e.g. no entry plus except buses) are separated by comma
|Key||Value||Element||Sign||Comment||Additional tags on the way|
|traffic_sign||city_limit||City or village sign.||zone:traffic=DE:urban|
|traffic_sign||maxspeed||Maximum speed sign. Usually tagged as node although they're actually section-related signs.||maxspeed=* + source:maxspeed=sign|
|traffic_sign||stop||Stop sign. Usually tagged as highway=stop instead.||highway=stop (on a node)|
|traffic_sign||give_way||Give way sign. Usually tagged as highway=give_way instead.||highway=give_way (on a node)|
|traffic_sign||overtaking||No overtaking sign.||overtaking=no|
|traffic_sign||maxwidth||Maximum width sign.||maxwidth=*|
|traffic_sign||maxheight||Maximum height sign.||maxheight=*|
|traffic_sign||maxweight||Maximum weight sign.||maxweight=*|
Traffic sign IDs
Signs specific to a particular country should be mapped by the country-indicating prefix followed by a colon and then the traffic sign.
- The country prefix should be the two-letter code. This prefix is separated by a colon
:from the sign
- Traffic signs should be represented by their official ID.
- Multiple unrelated signs should be separated with a semicolon
- If traffic signs are related, the additional sign IDs should be separated from the main sign by comma
- Where the traffic sign requires a value, you can supply it after the ID using brackets
[value]. The value may contain a dot
.as decimal separator and a minus
-for negative values.
Lists of IDs per country
- Belgium (wiki)
- Czech Republic (wiki)
- France (wiki)
- Germany (wiki)
- Poland (wiki)
- Russia (wiki)
- Turkey (wiki)
- United Kingdom (wiki)
- Ukraine (wiki)
- United States (Federal List) (wiki with state-by-state information)
JOSM has an icon for the value city_limit and also renders icons for the keys maxspeed=*, maxweight=*, maxheight=* and some more if tagged together with traffic_sign=*. While for maxspeed the actual value is shown, the other keys use a generic icon, which always shows the same value independent from the actual value specified in the respective tag.
The style Lane and Road Attributes currently renders traffic signs for maxspeed and overtaking. For maxspeed the icon shows the actual value specified in the tag.
The following table list some examples together with the actual rendering result in JOSM.
|Tags||Description||Rendering result in JOSM|
|Speed limit of 50 km/h|
|End of speed limit|
|Speed zone with 30 mph|
|Overtaking forbidden and a speed limit of 70 km/h|
|End of speed limit and overtaking is allowed.|
- RoadSigns plugin for the JOSM editor