[OSM-talk] NoName

[Ed Loach]

In the UK if you pass a speed limit sign it applies until you see
another, and you are likely to get most of a town at 30mph with
signs only around the outside. There is a sign which is a white
circle with a black diagonal line as per this document:
http://www.direct.gov.uk/en/TravelAndTransport/Highwaycode/Signsandm
arkings/index.htm?IdcService=GET_FILE&dID=96192&Rendition=Web
that is "national speed limit applies" which is 60mph on single
carriageway roads and 70mph on dual carriageways and motorways. I
think the highway codes also specifies it means 30mph in built up
areas where there are streetlights - 
rule 124 and table above here
http://www.direct.gov.uk/en/TravelAndTransport/Highwaycode/DG_070304
which also suggests the maxspeed can vary by vehicle type.

I asked about this here on the 8th, but didn't see any comments. I
felt that for this particular UK sign where it doesn't represent a
fixed maximum speed, but the current maximums by vehicle type that
the government determine (and a lot of old people I've met still
think it means 50mph on single carriageway roads not 60mph, and I
don't know whether this has ever been the case) that
maxspeed=national would be the most accurate solution. 

I've not been adding speed limits to any roads yet as the whole
thing seems a bit unclear, and I've almost added a whole town worth
of ways now. I have seen some discussion about different defaults
for different road types in different countries, and only tagging
those that differ, but that seems a bit tricky for mappers who may
not know about all these defaults and just want to map what they
see.

Ed