Proposal:Modifiers for access tags

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This proposal has been obsoleted by Proposed features/Conditions for access tags and Proposed features/Extended conditions for access tags.
Modifiers for access tags
Proposal status: Obsoleted (inactive)
Proposed by: Tordanik
Tagging: [[Key:maxspeed<:modifiers>, access<:modifiers>, ...|maxspeed<:modifiers>, access<:modifiers>, ...]]=[[Tag:maxspeed<:modifiers>, access<:modifiers>, ...=*|*]]
Applies to: *
Definition: an access tag with access modifiers only applies if all conditions given as modifiers are fulfilled

Draft started: 2009-01-16

Many common traffic regulations cannot be tagged properly because of the lack of a comprehensive and consistent way of limiting the restrictions to certain vehicle types, road conditions or road users. This proposal defines a set of access tag modifiers together with a way of adding them to the base tag.

Overview and initial examples


The modifiers are separated from the base key with a colon (':'). If, for example, only destination traffic is allowed to use a street with the hgv vehicle category, this can be tagged as

access:hgv = destination // note: bad example (could be expressed as hgv=destination), looking for better one ;-)

If multiple values with different modifiers are present, the most specific one that matches the current situation is used. So if the maxspeed differs depending on whether a road is wet or dry, this can be tagged as

maxspeed = 120
maxspeed:wet = 80

Modifiers are separated from each other using '&'. If there was an even lower maxspeed for hgv on the wet road mentioned above, this could be expressed by adding

maxspeed:hgv&wet = 60


This section lists all proposed modifiers.

vehicle categories

Any vehicle category (as listed on Key:access) is a possible modifier. The access tag is then only valid for vehicles from that category.

user categories

The user categories

  • private
  • destination

can be used as modifiers. The access tag is then only valid for users from that category.

weather conditions

German add-on sign "when wet"

The modifier

  • wet

describes that an access tag is only valid when the road is wet.


  • forward - access tag is only valid in way direction
  • backward - access tag is only valid in way direction

(Note that is different from lane-specific information: There are ways with direction-dependent restrictions that do not have multiple lanes. There also can be multiple lanes for each direction.)


Restrictions can be limited to vehicles with certain dimensions using

  • weight <comparator> <value>
  • height <comparator> <value>
  • width <comparator> <value>
  • length <comparator> <value>
  • axleload <comparator> <value>
  • draught <comparator> <value>

where <comparator> is one of '>' (more than) and '<' (less than). <value> is given as with maxweight, maxheight etc.



describes that vehicles (and animals) with a weight of more than 3.5 t must not move faster than 90 km/h.

Evaluating "conflicting" tags

  1. More specific information overwrites more general information (for a wet road, maxspeed:wet overwrites maxspeed).
  2. If there are conflicting tags without a "specificness" hierarchy, the most restrictive rule (e.g. lowest maxspeed) is to be chosen.

Notes on existing tagging

Some existing tags could be expressed with modifiers, for example

  • maxweight=3.5 is equivalent to access:weight>3.5=no
  • oneway=yes is equivalent to access:backward=no
  • cycleway=opposite is equivalent to oneway:bicycle=no (or access:backward&bicycle=yes)
  • ...

This proposal does not aim to abolish those existing tags, as the existing tags are widespread, shorter and more easy to understand.

possible extensions

  • time of day, dates (similar to weight etc., but requires time format)

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