Max Weight for "Combinations"
Here in the US, we sometimes have some bridges that have weight limits for trucks that have a single trailer, or for ones that have two. One bridge near where I live has the following sign for it (I'll post the picture later, but here's the text of it): BRIDGE | WEIGHT LIMIT 16 TONS | EXCEPT COMBINATIONS 26 TONS How can we go around to tag for this? --Rickmastfan67 05:02, 18 August 2010 (BST)
- In czech, we have sign for maxweight + table for "one wehicle" - ie: 25tons / 50tons one wehicle --Jezevec 22:18, 5 October 2012 (BST)
- Yes, and sometimes there is also no weight listed for the combinations (which I presume may mean that they are forbidden?). For example, this bridge was recently posted as 29 tons max except combinations. --Abbafei (talk) 04:24, 18 November 2014 (UTC)
Gross vehicle weight rating (GVWR)
Background / Research
There is a difference between the "actual weight" of a vehicle (as measured by a weighbridge) and its "gross vehicle weight rating" GVWR. The GVWR, or sometimes simply "Gross Vehicle Weight" is a maximum operating weight as specified by the manufacturer and recognised by the local state/government. For hgv routing, it is necessary to differentiate between those two. -- Eckhart 10:57, 22 November 2012 (UTC)
- Agree, we need this, because the the Vienna Convention on road signs defines both. The GVWR is called "permissible maximum mass" in the convention and is defined as "the maximum mass of the laden vehicle declared permissible by the competent authority of the State in which the vehicle is registered" [Article I, (r)]. The actual weight is called "laden mass" in the convention [Article I, (s)] and is defined as "actual mass of the vehicle as loaded, with the crew and passengers on board".
- If the convention has been accurately ratified by the state/government, then any weight value used in connection with a "no entry for goods vehicles", "prohibition of overtaking" and "speed limit" sign - no matter if inscribed or on an additional panel - means "permissible maximum weight" (i.e. GVWR). Thus:
- , or this German example means "No entry for goods vehicles with gross vehicle weight rating GVWR > X".
- also applies to HGVs with a gross vehicle weight rating GVWR > 7.5t only.
- For countries who accurately ratified the convention a standard weight restriction sign (such as or this German example) refers to the "laden mass" (i.e. actual weight). I think there is an agreement that roads with such signs should be tagged with maxweight=*. As correctly pointed out by Eckhart, gross vehicle weight is not needed for this type of sign.
- As this convention is implemented by many countries in the world we require a gross weight property in order to tag the road signs correctly.--Martinq 14:38, 22 November 2012 (UTC) and edited by RobJN 20:06, 27 November 2012 (UTC)
Austria I don't know if the Austrian law (StVO) defines a weight value under a speed limit sign as gross weight or just as weight. According to the convention it should be Gross Vehicle Weight Rating (GVWR), but the Austrian StVO neither clearly says 'weight' nor 'gross weight'.--Martinq 21:51, 22 November 2012 (UTC)
United Kingdom In the United Kingdom (and likely due to legacy non-metric signs) the Vienna Convention has not been ratified/implemented. All weight signs refer to the Gross Vehicle Weight Rating. For more see link.
- laden weight: and and and
- GVWR: with an additional panel stating the mass (that is, like in that German example above). (Prohibiton of overtaking and maxspeed signs may not have additional panels here.) Alv 22:20, 27 November 2012 (UTC)
Possible Solutions / Tags
- I would suggest using a new restriction tag (rather than a conditional property), for example hgv:max_gvwr=7.5. Alternatively the type of weight could be specified independently of maxweight=*. One possible way to do this is to tag maxweight:type=GVWR. --RobJN 20:06, 27 November 2012 (UTC)
Support for "no weight limit"
Some cases have no sign posted - what may be used to tag this? unsigned, none are rare but present. I prefer unsigned as there are sometimes some default limits (law typically limits dimensions and weight of vehicles, there are obviously also physical limits).
- It would be useful both to detect unsurveyed location and for routing to avoid routing over places where it is unknown whatever weight limit exists Mateusz Konieczny (talk) 18:34, 30 June 2017 (UTC)
- The vast majority of roads have no explicit weight limit posted, though, so this is clearly the default situation. When there's such a clear default, it's not common to explicitly tag the absence of a special case, even if such a value exists. (We don't tag oneway=no + bridge=no + tunnel=no + covered=no + access=yes on normal roads, for example). Now I'm aware that there are arguments in favour of doing exactly that, but it would at least be a significant change in existing tagging philosophies. --Tordanik 22:06, 1 July 2017 (UTC)