[Tagging] access restrictions on ways

[Philip Barnes]

On Mon, 2012-09-17 at 17:33 +0200, André Pirard wrote:
> On 2012-09-17 16:57,  David ``Smith'' wrote : 
> > Excuse me if I don't understand the situation entirely, but I think
> > the problem is the actual access restriction or enforcement of it is
> > different from a literal reading of the signs.  This must be the
> > case if the signs don't give adequate information to completely
> > describe the restriction. In that case, do your best to determine
> > the actual restriction as it is enforced and map accordingly.
> I gave extra info showing that this sign is more a fight shield that a
> road sign.
> But OSM must not inform readers of what road signs should be but of
> what they are.
> In everybody's mind, access restrictions is to an area because it
> reflects the places they can't reach.
> But the legal terms say that C23 is a signal you can't pass, one way,
> that's all.
> That's a node sign.
> > Access restriction tags on nodes should work fine for routers, but
> > remember if the node is an intersection, the access tags apply to
> > all movement through the intersection, and you probably want to
> > avoid that.  Also, such restrictions are less commonly visible on
> > rendered maps; for this reason I prefer to put access tags on ways
> > if reality can be accurately modelled that way. 
> > On the other hand, if the restriction exists at a point not at an
> > intersection and only for one direction of travel, I would have to
> > split the way there and make a no_straight_on turn restriction
> > relation with except= or for= tagging to indicate what vehicles are
> > or are not prohibited. 
> > Also, if a road does not permit passage of vehicles unless it's the
> > only choice (such as going to or from that road or a side street
> > with no other outlet) then remember access=destination (or
> > hgv=destination, or whatever else might apply) is something we can
> > do. 
> And if you want to make it a way restriction, that's up to the point
> where other users could not see the signal.  Over 50m in this
> example !!!
> 
I must admit I have more my sabre roads (http://www.sabre-roads.org.uk/
) hat on, rather than OSM at the moment, but are you sure this is a
legal restriction?

A restriction in one direction is very odd. You mention someone who does
not like trucks going past her house, that is not a reason for a
restriction. The council not answering your question is again odd in a
democratic country. Do you have a freedom of information act?

Are you sure they have not just put up a sign that is unenforceable to
keep her quiet?

Do the local trucker take any notice of the restriction, ask one for
their opinion,  if Belgium is anything like the UK every pub/bar will
have a trucker or two who will be more than willing to share such woes.

I cannot find the sign on streetview, can you link it? or have you got a
photo?

You mention shields, I associate shield signs with North America. In
Belgium it should be a round sign.

Phil