Talk:Key:maxweight
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.
Finland
- 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 propose to add the vehicle property "grossweight". Example usage: hgv:conditional=no @ (grossweight>7.5) -- Eckhart 10:57, 22 November 2012 (UTC)
- 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)
- It seems the solution is maxweightrating=*, it is documented and has growing usage, especially in combinations like maxweightrating:hgv=*. Some examples (e.g. the Greek trailer sign), seem to refer to maxweightrating rather than to maxweight (but I may be misguided, no idea about Greek traffic law). --Dieterdreist (talk) 07:36, 4 October 2019 (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).
So, I propose to mention "unsigned" at wiki page Mateusz Konieczny (talk) 14:03, 30 June 2017 (UTC)
- 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)
- I thought about doing it for bridges, obviously doing it for every single road would be ridiculous. Mateusz Konieczny (talk) 08:00, 3 July 2017 (UTC)
- How about maxweight:signed=no? I think this scheme is used in a couple of other places as well already. --Westnordost (talk) 21:00, 26 January 2019 (UTC)
- maxweight:signed=no seems to be a good idea Mateusz Konieczny (talk) 08:02, 20 June 2019 (UTC)
- I added it to maxweight page Mateusz Konieczny (talk) 08:24, 3 July 2019 (UTC)
- maxweight:signed=no seems to be a good idea Mateusz Konieczny (talk) 08:02, 20 June 2019 (UTC)
- How about maxweight:signed=no? I think this scheme is used in a couple of other places as well already. --Westnordost (talk) 21:00, 26 January 2019 (UTC)
- I thought about doing it for bridges, obviously doing it for every single road would be ridiculous. Mateusz Konieczny (talk) 08:00, 3 July 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)
Units
The page Units list the default units. There is no required unit forthis or any other dimension, use the unit of the feature and add the unit after the number separated by a space. Please use units that are identifiable and in common use. If the page Units does not list the units you are using consider adding it there. Warin61 (talk) 23:02, 26 January 2019 (UTC)
Abbreviation for U.S. short ton
@Westnordost: Thanks for noting the distinction between short and long tons. Your example uses "st" as an abbreviation for "short ton"; however, "st" can also be an abbreviation for the stone, another unit of weight. Are we sure that there are no legitimate uses of stones in other tags that could cause confusion with this usage? (I don't know, maybe something related to horse racing facilities?) Most U.S. mappers have avoided this issue entirely by converting to (international) pounds with the suffix "lb" or "lbs". – Minh Nguyễn 💬 06:11, 18 April 2019 (UTC)
- The "st" in OSM context has always been defined as "short tonnes", see https://wiki.openstreetmap.org/wiki/Map_Features/Units#Explicit_specifications . If something really is specified in stones in reality, another abbreviation/unit must be used. I.e. "stones" - it's not that long ^^ --Westnordost (talk) 09:15, 18 April 2019 (UTC)
- @Westnordost: Looks like the
st
suffix was added to the page a year ago by Maxerickson and was used for the first time in OSM on May 24. [1] Mappers have been entering short tons as pounds since at least 2009, and in much greater numbers. Has this change to the wiki been discussed anywhere else? Do we know if any data consumers know how to handlest
, or do we need to raise awareness of the suffix? I could imagine a scenario where truck routers have been parsinglb
andlbs
all these years, based on existing usage, but their developers would be caught by surprise as that suffix gets replaced byst
on some important road. – Minh Nguyễn 💬 23:04, 24 April 2019 (UTC)
- @Westnordost: Looks like the
- Yes, I added it out of frustration with the circular logic that people were using to argue against adding values that appear directly on signs. It wasn't documented in the wiki, so people said it wasn't okay to use it. I'm pretty sure that people accidentally tried to use it (or just put t) lots before I added it and then had their edits fiddled into the lbs. Maxerickson (talk) 21:22, 26 April 2019 (UTC)
- @Maxerickson: Fair enough; that's also my understanding of what has happened in the past. Have there been any mailing list discussions and bug reports for editors and routers that you know of? I like the
st
suffix in principle, but it feels like more needs to be done in order to make the suffix a reality. – Minh Nguyễn 💬 01:11, 27 April 2019 (UTC)
- @Maxerickson: Fair enough; that's also my understanding of what has happened in the past. Have there been any mailing list discussions and bug reports for editors and routers that you know of? I like the
Restrictions for different classes of HGV
@Minh Nguyễn
Regarding the example you added for this sign, the current tagging written there is wrong, probably a copy&paste error.
But the question is, how to map this at all? There is hgv_articulated=* for the second row, but no hgv_trailer=* or similar for the third (yet). But since having a trailer is a property any vehicle may temporarily have, it is maybe not appropriate to define hgv_trailer, bus_trailer, car_trailer etc. etc. but solve this instead with conditionals. Does this make sense?:
maxweight:hgv=8 st
maxweight:hgv_articulated=12 st
maxweight:hgv:conditional=16 st @ (trailer)
—Preceding unsigned comment added by Westnordost (talk • contribs) 09:28, 18 April 2019 (UTC)
@Westnordost: Yeah, I didn't realize the sign was distinguishing between box trucks and trailer tractors, so I used maxaxleload=* as a shortcut; my mistake. I'll admit that I generally find MUTCD weight limit signs almost as confounding as MUTCD hazmat signs, so I'm glad you're double-checking my changes. (For reference, this particular sign is described in the national standard.) I think your suggestion makes sense, though I wonder if maxweight:hgv=* should be tagged at all or whether both conditions should be listed in maxweight:hgv:conditional=*.
For what it's worth, I just picked an image that was already available on Commons, but the weight limit signs can get more complex. For example, the "Single Unit Vehicles" sign in this photo is meant for garbage trucks, water tankers, and the like. I'm not sure if I got the tagging right in 153028430 153028430.
– Minh Nguyễn 💬 23:18, 24 April 2019 (UTC)
- That looks about right. Man, these signs are so small, you need binoculars to read them as a truck driver! :-o
- Would have been easier for the road traffic authority to post a maxaxlewheight sign with roughly the same outcome --Westnordost (talk)
- I'd imagine the primary purpose of a sign like that would be to give the police a better legal argument if a truck driver challenges a citation. But truck drivers often have other ways to be informed of the most important restrictions, whether it's a weigh station (as in this case), statewide hotlines, automated broadcasts over localized CB radio (which would be an interesting feature to map for sure), or routing applications. – Minh Nguyễn 💬 23:53, 25 April 2019 (UTC)
- I found http://www.calhouncountyroads.com/about/services/bridge-data/weight-limit-signs/ that link document with 25 truck types ("The 25 trucks represent different truck configurations allowed on Michigan roads."), and explains that "Unit 1: Represents truck 1 to 5", "Unit 2: Represents truck 6 through 18", "Unit 3: Represents truck 19 through 23". One of fun facts is that truck 24 and 25 is apparently not covered by this weight restrictions Mateusz Konieczny (talk) 14:13, 5 July 2019 (UTC)
Gross weight
When the U.S. R12-4 sign says "gross", does it actually refer to maxweightrating=*? The standard for this sign makes reference to the normal weight restriction sign. This guide from the Iowa DOT doesn't refer specifically to R12-4 but does say that R12-1 makes a distinction between the "total weight of a vehicle on a bridge" and the "gross weight of the entire vehicle". So it sounds like "gross" in this context just means "whole vehicle" and isn't necessarily a reference to GVWR. – Minh Nguyễn 💬 20:37, 25 June 2019 (UTC)
This FHWA brochure says all these signs express gross vehicle weights (GVW), and this Energy Department FAQ defines GVW as the maximum rated weight. So that would mean the MUTCD only calls for maxweightrating=* and never maxweight=*. If this is the case, then we finally have an answer for how to tag R12-3 (with maxweight=*), but on the other hand, we have a lot of roads to retag. But this article makes a distinction between GVW and GVWR, so I'm really unsure. – Minh Nguyễn 💬 21:43, 25 June 2019 (UTC)
- "If this is the case, then we finally have an answer for how to tag R12-3 (with maxweight=*)" - wait, so by "empty wt" they mean "current weight", not "weight of a vehicle itself, without counting cargo"? Mateusz Konieczny (talk) 05:19, 26 June 2019 (UTC)
- Oh, no, “empty weight” is really just the unladen vehicle itself. I haven’t found a single occurrence of it being tagged so far, but I may be looking for the wrong words. (It wouldn’t be the first time.) Is there an equivalent in other countries? – Minh Nguyễn 💬 05:33, 26 June 2019 (UTC)
- "equivalent in other countries" - I am not aware about one for Poland Mateusz Konieczny (talk) 21:10, 28 June 2019 (UTC)
Illinois MUTCD R12-I100 - is it really HGV only?
https://wiki.openstreetmap.org/wiki/File:Illinois_MUTCD_R12-I100.svg is not specifying anywhere that it applies only to HGV and busses/agricultural machines etc are excluded. I would expect recommeneded tagging to include maxweight 17 st=*. The same for most of other examples added for Illinois Mateusz Konieczny (talk) 08:01, 5 July 2019 (UTC)
- I'm not familiar with all the laws surrounding weight restrictions in Illinois, but unlike the length restrictions that PSVs and agricultural machinery are sometimes exempted from, weight restrictions are usually posted due to bridge structural issues, which affect any kind of vehicle. So I think it's reasonable to remove the
:hgv
qualifier until we find out for certain whether Illinois state law exempts specialized vehicles from the "single vehicle" restrictions by default. – Minh Nguyễn 💬 12:13, 5 July 2019 (UTC)- Changed Mateusz Konieczny (talk) 14:08, 5 July 2019 (UTC)
To do
More common signs that I haven't gotten around to vectorizing yet:
- California: W20, W20a [2][3][4][5] (maxweight:advisory=*)
- California: "No Trucks Over ___ Tons" [6] (not state-standard, but very common at the municipal level)
Delaware: R12-5-DE [7]- Maryland: R12-1(2) [8], R12-5(1) [9], R12-5(2) [10], R12-5(3) [11], R12-5(4) [12]
Ohio: R12-H17 "Weight Limits Reduced ___%" [13][14] (appears to be based on [15][16][17])- Ohio: "Bridge: Legal Limit Reduced ___% for Total Weight and Axle Loads" [18][19] (no longer state-standard)
Puerto Rico: R12-1, R12-5 [20][21] (pretty sure Puerto Rico uses short tons)- Vermont: Legal Load Limit ___ Pounds
- Virginia: R12-V2, R12-V3, R12-V4, R12-V5, R12-V6 [22] (no layout specifications yet)
– Minh Nguyễn 💬 20:43, 5 July 2019 (UTC)
Mandatory weigh station usage by weight
I'm thinking of adding this example, but I don't know of a concise way to explain what you need to apply the tag to:
United States:
maxweight:hgv=10 st
(tag on the section of highway=motorway way starting from the upcoming highway=motorway_junction node and ending at the following intersection with a highway=motorway_link way)
Here's a crude illustration, with the affected way represented by :::
:
===o:::::::::::::::::::::::o===> \____weigh station____/
– Minh Nguyễn 💬 05:48, 7 July 2019 (UTC)
- "tag on the section of road that must be avoided by trucks directed to weigh station"? Mateusz Konieczny (talk) 19:47, 7 July 2019 (UTC)
Passenger weights
aerialway=zip_line and attraction=roller_coaster sometimes restrict passengers by weight. Since signage is normally expressed in human-scale units like kilograms and pounds, mappers sometimes indicate these weights without units, which could result in some abnormal treatment by data consumers that blindly follow this wiki's unit documentation. [23] – Minh Nguyễn 💬 23:25, 13 October 2019 (UTC)
- What you're describing (omitting non-standard units) is simply a mapping error, though. Personally, I don't think the maxweight key should be used for passenger weight at all, as it has so far be predominantly used for vehicle weight. --Tordanik 11:31, 5 January 2020 (UTC)
- I agree with Tordanik, for passenger weights a new key should be used.—Dieterdreist (talk) 12:08, 5 January 2020 (UTC)
- Concerning "vehicle weight", there are exactly 2 maxweight:bicycle=none instances used to exclude them from maxweight=*. Bicycles also face weight limit in kg to be carried on transit, in particular for storing on racks. ---- Kovposch (talk) 13:56, 8 September 2020 (UTC)
- This distinction came up in Homonymous keys, so I took the liberty of specifically calling out the use of this key for passenger weights. It may be homonymous, but passenger weight usage has been documented elsewhere on the wiki since 2014 and was possibly being used even before that. – Minh Nguyễn 💬 23:06, 28 November 2021 (UTC)
Weight limit reduction signs
After a few days of research, I managed to come up with a machine-readable representation of Ohio's standard traffic_sign=US:OH:R12-H17, which counties and townships often post on roads and bridges to protect them during thawing season. (Other northern states have similar provisions.) The sign implicitly refers to a complex section of the state legal code that defines the legal truck configurations and weight limits associated with each configuration. I tried to distill that down into the usual conditional tagging syntax:
maxweight:conditional=12 st @ (Feb 1-May 15) maxweight:hgv:conditional=12 st @ (Feb 1-May 15 AND axles=2); 36800 lbs @ (Feb 1-May 15 AND axles=3); 43200 lbs @ (Feb 1-May 15 AND axles=4); 49600 lbs @ (Feb 1-May 15 AND axles=5); 55600 lbs @ (Feb 1-May 15 AND axles=6); 31 st @ (Feb 1-May 15 AND axles>=7) maxweight:hgv_articulated:conditional=32 st @ (Feb 1-May 15)
There are currently eight legal truck configurations in Ohio: 2F1, 3F1, 4F1/SU4, SU5, SU6, SU7, and 5C1. [24] The SU* configurations are for special hauling vehicles (SHVs), also known as single unit vehicles, for example cement trucks and garbage trucks. These configurations are uniform throughout the country, but the others may vary by state.
Configuration | Axles | Articulated | Unreduced legal limit |
---|---|---|---|
2F1 | 2 | no | 15 short tons (14 t) |
3F1 | 3 | no | 23 short tons (21 t) |
4F1 | 4 | no | 27 short tons (24 t) |
SU4 | 4 | no | 27 short tons (24 t) |
SU5 | 5 | no | 31 short tons (28 t) |
SU6 | 6 | no | 34 3⁄4 short tons (31.5 t) |
SU7 | 7 | no | 38 3⁄4 short tons (35.2 t) |
5C1 | 5 | yes | 40 short tons (36 t) |
The configurations are primarily known by the number of axles, and secondarily by whether the truck is a single unit (including a special hauling vehicle with closely spaced axle groups) or a truck-trailer combination. The general-purpose weight limit sign, traffic_sign=US:OH:R12-H5, identifies the configurations by these two aspects. However, the regulations are very particular about how the spacing between any two axles and how much weight is applied to each axle. In some configurations, the axles are unevenly spaced and have different weights applied to them. For both signs, I ignored everything except for the axle count and unit count. I'm assuming that any truck configuration that's illegal in the State of Ohio would be out of scope for the maxweight=* key anyways.
I alternated between expressing some limits in short tons and others in pounds. In Ohio, the authorities use pounds and kips in regulations and manuals, but they only post tonnages on signage. (Compare to Texas, which only uses pounds on signage.) I only used pounds for some cases because the percentage reduction would've resulted in a fractional limit and ambiguity about rounding and significant digits.
Given that the weight limit reduction sign is relative to unsignposted state laws, the actual values will change the next time the law changes. This is unfortunate but, in my opinion, an acceptable tradeoff for keeping data consumers from having to navigate the complexity of legal load limits that vary by state. The relevant state law was last updated in 1993, though the SHV configurations were introduced more recently, around 2016. I don't expect the laws to change frequently. But just in case, I've also been mapping the traffic_sign=*s and also adding an ad-hoc maxweight:relative=-20%, which will make it easier to find the roadways to update.
This effort was only for a single standard sign design in Ohio, but hopefully the reasoning here will help others as they try to make sense of regulations and signage in other U.S. jurisdictions.
(Cross-posted on my diary.)
– Minh Nguyễn 💬 19:15, 3 October 2020 (UTC)
Elevators
highway=elevator has documented maxweight=* for passenger weight limits since 2015. However, I've yet to come across an elevator that posts a specific weight limit for an individual passenger. It's much more common to post a maximum capacity, a total of the weights of all the passengers and cargo. After all, it would be easy but dangerous to circumvent a passenger weight limit by squeezing in another passenger. Yet capacity=* doesn't document weight-based values, and they don't appear to be very common in the database either. Are we OK with the fact that the key sometimes indicates the maximum weight of an individual vehicle, sometimes the weight of an individual passenger, and sometimes the total weight of all the passengers? – Minh Nguyễn 💬 23:24, 28 November 2021 (UTC)
- elevator:maxweight=*? maxweight=* + maxweight:foot=none? capacity=* is a volume. ---- Kovposch (talk) 08:00, 29 November 2021 (UTC)
- @Kovposch: capacity=* is only sometimes a volume. It can also be the maximum occupancy of a room, for example. It's one of the most diversely interpreted keys out there. – Minh Nguyễn 💬 10:08, 29 November 2021 (UTC)
Postal Services
Some courier services have explicit limits on parcel weight and size: smaller ones e.g. up to 10 kg may be deivered to an amenity=parcel_locker, bigger ones e.g. up to 30 kg may be retrieved from an amenity=post_office, and for anything heavier one has to go directly to an amenity=post_depot or order a home delivery. Would it be a good practice to use this tag for postal services, or it would be better to create a separate tag? – VileGecko (talk) 13:22, 31 January 2022 (UTC)
Weight limits for some vehicles only
Have found a road that is signed as "Max 3 tonnes, buses excepted".
How to map it?
I'm guessing with maxweight:conditional but can't figure out what conditions to apply? --Fizzie41 (talk) 00:10, 20 February 2022 (UTC)
- If there is no further condition like date, time, length, count of axles, etc., conditional is not needed. The most simple solution I see is: maxweight=3 + maxweight:bus=no (instead of "bus" you may use "psv" if that is common at the place you are mapping or if the connected streets are tagged that way). --Chris2map (talk) 08:11, 20 February 2022 (UTC)
Thanks! I had thought about that, but kept thinking that would mean that only buses with no weight could enter! :-) --Fizzie41 (talk) 22:47, 20 February 2022 (UTC)