[Tagging] US Speed Limits, truck routes, bike routes, access
Alan_Mintz+OSM at Earthlink.Net
Fri Feb 26 22:32:20 GMT 2010
Several issues with relation to speed limits:
1. How should one tag "suggested" speeds (usually around curves) like
Should I tag them as maxspeed=*? I can see being cited for exceeding it
according to the blanket "safe speed" provisions in some vehicle codes.
2. I've been tagging 25 mph school zones
as "maxspeed:children_present=25 mph". Can someone comment on where such
zones end (I realize this may, again, be jurisdiction-dependent)? I
sometimes, but not always, see an "End School Zone" sign (should I tag
these, and how?).
3. Based on the recent conversation about source:*=*, when I tag a way with
maxspeed=*, I've been adding source:maxspeed and source_ref:maxspeed as
- I photograph (ref1) a speed limit sign at point A, saying 40 mph.
- I create a node on the curb of the road at point A, tagged:
- I photograph (ref2) the very next speed limit sign I see - at point B,
saying 35 mph.
- I create a node on the curb of the road at point B, tagged:
- I split the way so that I have a segment between point A and B.
- I tag the segment:
If I see additional identical speed-limit signs along the way, I tag the
nodes, but do not split the way. I tag the way with the refs for the
4. Similarly, for school zones, I'm tagging the ways:
I changed the ":" to "_", not being sure if we want to deal with multiple
levels of children.
5. For separate limits for trucks, I'm using:
6. For separate limits for towing/towed vehicles, I'm using:
In CA, the standard speed limit on freeways is 65mph normally, but 55mph
for trucks and towing/towed vehicles. This results in 9 tags(!), providing
more reason for some sort of scheme like maxspeed=freeway.
7. Similarly, for truck routes, I create a node for the signs, tagged:
and tag the ways:
For bike routes, the same, replacing hgv with bicycle.
8. In rural areas especially, there is often confusion between county
records, existing databases (e.g. TIGER, TeleAtlas), and posted signs, as
to what portion of a road is considered "private". This is an area where I
believe OSM and actual in-person surveying has the potential for great
value over other maps. I'd like to create a node where I first see a "No
Trespassing" sign (http://en.wikipedia.org/wiki/File:No_trespassing_sign.jpg).
Should I tag the node access=private [+source=* +source_ref=*]? I'll note
that JOSM has an icon for access=no, but not access=private. I can then tag
the way with source:access=* +source_ref:access=*.
That is, holding that the sign states what is taken to be the prima
facie safe speed. Any traffic court judges here?
survey because I saw it, image because I photographed it, and
usgs_imagery because I used it to find the curb.
Alan Mintz <Alan_Mintz+OSM at Earthlink.net>
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