Double negatives - "No trucks no left turn"

[Mr. Matté]

So not too long ago I had a quandary when it came time to designing traffic signage for a site I was working on. The project is for a warehouse and due to the street it's on, trucks exiting the site cannot make a left turn. I wanted to keep the signage simple without creating custom regulatory signage so I figure just use standard signs from the MUTCD. I've seen examples of signage on a single post like below but if literally read out, it would read "No trucks no left turn:"



While drivers would get the gist, there's always that one case where someone wants to challenge a ticket on the grammatical interpretation of a sign (see also the alleged "No Stoping" judgement). To combat that, I proposed using a "TRUCK" banner and the R3-2 sign:




At least this conveys "Trucks no left turn" though the banner is more intended for numbered truck routes. I've seen this configuration before as well and the project was approved with the signage as shown above. But since there's no specific mention of how to restrict turns by vehicle in the MUTCD, is there a standard way of configuring the signs?

[sprjus4]

I've seen this configuration used more than once.

https://www.google.com/maps/@35.4702845,-77.1191635,3a,39.2y,168.73h,83.84t/data=!3m6!1e1!3m4!1sJhwNt-OUH0gobUu-F26TIQ!2e0!7i13312!8i6656!5m1!1e1

[NoGoodNamesAvailable]

what about a text regulatory sign "NO LEFT TURN FOR TRUCKS"?

[rickmastfan67]

Here's a 'NO RIGHT TURN TRUCK' sign that I know of. https://goo.gl/maps/9L2Jof8GAhirkYz3A

Maybe put the 'TRUCK' banner below the 'NO LEFT TURN'?

[berberry]

Great topic! What if we add the appropriate logical operator into the mix? It would certainly make things unambiguous, from a purely logical standpoint, if we were to put a sign saying "OR" right in the middle. This should avoid the kind of court challenge mentioned upthread, because who wants to go before a judge and say "the word 'OR' confuses me"? Clearly, the signs would be saying "if you wish to do either one of these things, DON'T DO IT HERE!" But how many drivers would interpret it that way?

[SectorZ]

https://www.google.com/maps/@42.7580232,-71.4202311,3a,35.9y,25.38h,80.64t/data=!3m6!1e1!3m4!1sU2fO0muUtaimSDNuv_uMxA!2e0!7i13312!8i6656

Even better, is if you drive down this road, Google Maps thinks you can't take a left or right, in any vehicle.

[Brian556]

So not too long ago I had a quandary when it came time to designing traffic signage for a site I was working on. The project is for a warehouse and due to the street it's on, trucks exiting the site cannot make a left turn. I wanted to keep the signage simple without creating custom regulatory signage so I figure just use standard signs from the MUTCD. I've seen examples of signage on a single post like below but if literally read out, it would read "No trucks no left turn:"



While drivers would get the gist, there's always that one case where someone wants to challenge a ticket on the grammatical interpretation of a sign (see also the alleged "No Stoping" judgement). To combat that, I proposed using a "TRUCK" banner and the R3-2 sign:




At least this conveys "Trucks no left turn" though the banner is more intended for numbered truck routes. I've seen this configuration before as well and the project was approved with the signage as shown above. But since there's no specific mention of how to restrict turns by vehicle in the MUTCD, is there a standard way of configuring the signs?

I've seen the double negative one many times. Shows you how dumb the people responsible for signage really are.

Here's one that uses a WATCH FOR TRUCKS SYMBOL SIGN instead of the plaque. It is posted by TxDOT District 2, which has always sucked at signing:
https://www.google.com/maps/@33.0261527,-97.4446064,3a,37.5y,254.92h,89.15t/data=!3m7!1e1!3m5!1sQpp9-hLrjuKTYz7ektBBbQ!2e0!6s%2F%2Fgeo2.ggpht.com%2Fcbk%3Fpanoid%3DQpp9-hLrjuKTYz7ektBBbQ%26output%3Dthumbnail%26cb_client%3Dmaps_sv.tactile.gps%26thumb%3D2%26w%3D203%26h%3D100%26yaw%3D274.48703%26pitch%3D0%26thumbfov%3D100!7i16384!8i8192

[djlynch]

The other thing that I've seen is to combine the R5-2 "no trucks" symbol with an M5-1 or M6-1 arrow, essentially saying "no trucks to the left/right" instead of "no left/right turn for trucks." I think I personally prefer that to the turn prohibition and a truck banner because I've seen the combination (with the truck banner on the bottom) at the entrance to a shopping center and it left me confused momentarily as to whether it meant no turn for trucks or that the entrance was meant for trucks and nobody else should turn.

[roadfro]

I know of two similar instances of a turn restriction for trucks only.

N McCarran Blvd NB at Nichols Blvd in Sparks, NV (which is right next to a TA Travel Center). On the near side corner of the intersection, a custom sign is used: "TRUCKS" / (symbolic "no right turn") / "NO RIGHT TURN". A separate symbolic "No trucks" sign (with a rear-profile truck, which is not meant to be used in this context) is confusingly and unnecessarily posted beneath. On the far side corner of the intersection is a custom sign that is essentially just a symbolic "no right turn" with a "trucks" banner underneath.

The very next intersection, N McCarran Blvd NB at Lincoln Way also has a truck turn restriction. This one just has one sign on the far corner similar to the previous far side sign.

The other thing that I've seen is to combine the R5-2 "no trucks" symbol with an M5-1 or M6-1 arrow, essentially saying "no trucks to the left/right" instead of "no left/right turn for trucks." I think I personally prefer that to the turn prohibition and a truck banner because I've seen the combination (with the truck banner on the bottom) at the entrance to a shopping center and it left me confused momentarily as to whether it meant no turn for trucks or that the entrance was meant for trucks and nobody else should turn.

While I like the concept, this can also be misinterpreted as "no trucks allowed on the road to the right". In the examples I posted, the right turn prohibition for trucks is due to the turning radius of the NB right turn–SB left turning trucks and EB through trucks are still allowed.

I think the best option is the second figure Mr Matte posted: Truck placard above the turn restriction sign.

Perhaps the MUTCD should develop mode symbol banners that can be placed above regulatory signage to indicate that a sign's restrictions or instructions only apply to that mode.

[US71]

There's a sign on the Cimarron Turnlike in Oklahoma that seems to say "NO 'NO U TURN'"

[CtrlAltDel]

Great topic! What if we add the appropriate logical operator into the mix? It would certainly make things unambiguous, from a purely logical standpoint, if we were to put a sign saying "OR" right in the middle. This should avoid the kind of court challenge mentioned upthread, because who wants to go before a judge and say "the word 'OR' confuses me"? Clearly, the signs would be saying "if you wish to do either one of these things, DON'T DO IT HERE!" But how many drivers would interpret it that way?

I can't really think of a situation where this would be relevant, though. Like if a sign said, "No left turns, trucks or buses," I don't think you'd be able to get out of a ticket by claiming that you were driving a truck and a bus, and thus, that the sign didn't apply to you.

[jakeroot]

Truck signs are usually white-on-black, right? How about this...

[CtrlAltDel]

Truck signs are usually white-on-black, right? How about this...

I can't help but think that this would be better, though.

[jakeroot]

I can't help but think that this would be better, though.

Sure. I was just trying to stick to the "black background for trucks" rule that is largely not followed, or perhaps not even a rule anymore.

[ClassicHasClass]

To combat that, I proposed using a "TRUCK" banner and the R3-2 sign:

Caltrans thought so too (US 101 near Salinas):

https://goo.gl/maps/V6zFqCcf8FuebjHE9

[US71]

I can't help but think that this would be better, though.

I've seen this somewhere

[Dustin DeWinn]

[US71]

Here's the Cimarron Turnpikw sign

[roadfro]

Truck signs are usually white-on-black, right? How about this...

I can't help but think that this would be better, though.

While either I think would convert the message, the second black on white version is what I was envisioning.

[D-Dey65]

So not too long ago I had a quandary when it came time to designing traffic signage for a site I was working on. The project is for a warehouse and due to the street it's on, trucks exiting the site cannot make a left turn. I wanted to keep the signage simple without creating custom regulatory signage so I figure just use standard signs from the MUTCD. I've seen examples of signage on a single post like below but if literally read out, it would read "No trucks no left turn:"



While drivers would get the gist, there's always that one case where someone wants to challenge a ticket on the grammatical interpretation of a sign (see also the alleged "No Stoping" judgement). To combat that, I proposed using a "TRUCK" banner and the R3-2 sign:




At least this conveys "Trucks no left turn" though the banner is more intended for numbered truck routes. I've seen this configuration before as well and the project was approved with the signage as shown above. But since there's no specific mention of how to restrict turns by vehicle in the MUTCD, is there a standard way of configuring the signs?

To me, the double negative that you're complaining about seems like it might be a different message than the truck banner above the No Left Turn sign. I've seen plenty of No Left Turn signs with truck banners and other banners as well. Case in point, this one on westbound FL 50 near a local biker bar;
https://www.google.com/maps/@28.5374408,-82.4697301,3a,75y,218.38h,94.46t/data=!3m6!1e1!3m4!1snnHahlTvJUosqkNUBdlHgQ!2e0!7i16384!8i8192?hl=en


The other one is just a no trucks sign and a no left turn sign at the same site.

I can't help but think that this would be better, though.

I've seen this somewhere

I have to say, I like Jakeroot's variation better.

[kphoger]

The other one is just a no trucks sign and a no left turn sign at the same site.

I agree.  If I saw that sign, I would interpret it thusly:

  1.  No trucks beyond this point.
  2.  No left turn.

[hotdogPi]

I searched and can't find it (it's probably in Lynnfield or Wakefield MA), but I found this in Google Street View:

No turn on red
[picture of truck] excluded

Obviously meant to be two separate things, but that's not what it implies.

[Henry]

Truck signs are usually white-on-black, right? How about this...

I can't help but think that this would be better, though.

While either I think would convert the message, the second black on white version is what I was envisioning.

Personally, I prefer the second sign over the first, although either one would make the restriction a lot more clear. To have both NO TRUCKS and NO LEFT TURN symbols together is very confusing, because it is not known whether trucks are not allowed to turn left or altogether banned on the specific road.