Roy Wallace <waldo000...@gmail.com> schrieb: > On Tue, Jul 28, 2009 at 11:04 AM, Ross Scanlon<i...@4x4falcon.com> > wrote: > > Does this mean the bridge has a clearance of 2.8 or the road under > > the bridge has a clearance of 2.8. To me this would suggest the > > bridge has a limit of 2.8 ie vehicles travelling over the bridge > > can not be above 2.8 high. > > > > I'd suggest that if the bridge has a height limit, ie clearance, > > then the bridge is tagged with max_height. > > > > If the road under the bridge has a height limit, ie clearance, then > > the road is tagged. > > Sorry, maybe this is a language issue. In my mind, "height limit" of a > way refers to maximum height *above* the way, whereas "clearance" of a > way infers maximum height *under* the way. Maybe "clearance" isn't the > best word for this - please suggest others.
According to Wikipedia "clearance" [1] is the free space between a vehicle and the structure (i.e. bridge) it is passing through. The maximum height (and width) of the vehicle is -- at least for railways -- called "loading gauge" [2] while the dimensions of the structure are called "structure gauge [3]. Thus, what we find on signs is the loading gauge. Christoph [1] http://en.wikipedia.org/wiki/Clearance [2] http://en.wikipedia.org/wiki/Loading_gauge [3] http://en.wikipedia.org/wiki/Structure_gauge _______________________________________________ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk