multilane exit signage on freeways

[roadfro]

I had a quick look at the Final Rule Notice to see how FHWA had addressed diagrammatic signs, which was the main burden of my own submission.  They did pretty much as I had suggested in my letter, though they did not go into detail on the reasons.  Stippled-arrow diagrammatics are still in the MUTCD, while arrow-per-lane diagrammatics are now an accepted design option.

It should be noted that the arrow-per-lane signs are now the preferred design option, with the diagrammatic signs retained as an option.


On a related topic, I don't agree with some of the new standards relating to multilane exits/splits.  I noticed that many figures are now revised to show exit direction signs placed directly above the exit's theoretical gore, where previously such signs were placed slightly ahead of this point. With the revised designs, this sometimes results in signs that indicate two exit only lanes when there really is one exit only lane and one optional lane.  This seems to me to have the potential to confuse drivers about the exit conditions in certain situations.

A specific problem I have is that the new standards prohibit the way Nevada DOT regularly marks exits multilane exits.  Generally, an exit with a drop lane and an option lane will be marked with a green-on-white down arrow over the option lane a black-on-yellow down arrow over the drop lane on the advance sign, followed by an exit direction sign with appropriate up arrows.  This signage would be used at any exit with an option lane, not just those where a route splits.  Here's Google Street View images of a typical application on US 95 north in Las Vegas: Advance guide sign and Exit direction sign

However, FHWA believes that drivers misinterpret the green-on-white down arrow as a dedicated lane, prompting excessive/unwarranted lane changes.  Thus, their solution is to prohibit this signing method in favor of this: replacing the advance guide sign with one that shows one arrow for the exit only lane, add at least two regulatory lane-use signs on the shoulder that point out the option lane, add lane control arrow pavement markings adjacent to each lane-use sign, and reposition the exit direction sign over the exit gore point and replace it with one that shows two exit only arrows.  To me, this is a lot more signs/markings for the DOT to maintain, there is additional signs which could contribute to sign clutter, and the exit direction sign is now potentially misleading.  In my view, none of the new MUTCD standards show adequate overhead signing for this common condition except arrow-per-lane signing, which would be an excessive amount of signing for how often this kind of exit configuration is used.

[myosh_tino]

On a related topic, I don't agree with some of the new standards relating to multilane exits/splits.  I noticed that many figures are now revised to show exit direction signs placed directly above the exit's theoretical gore, where previously such signs were placed slightly ahead of this point. With the revised designs, this sometimes results in signs that indicate two exit only lanes when there really is one exit only lane and one optional lane.  This seems to me to have the potential to confuse drivers about the exit conditions in certain situations.

A specific problem I have is that the new standards prohibit the way Nevada DOT regularly marks exits multilane exits.  Generally, an exit with a drop lane and an option lane will be marked with a green-on-white down arrow over the option lane a black-on-yellow down arrow over the drop lane on the advance sign, followed by an exit direction sign with appropriate up arrows.  This signage would be used at any exit with an option lane, not just those where a route splits.  Here's Google Street View images of a typical application on US 95 north in Las Vegas: Advance guide sign and Exit direction sign

However, FHWA believes that drivers misinterpret the green-on-white down arrow as a dedicated lane, prompting excessive/unwarranted lane changes.  Thus, their solution is to prohibit this signing method in favor of this: replacing the advance guide sign with one that shows one arrow for the exit only lane, add at least two regulatory lane-use signs on the shoulder that point out the option lane, add lane control arrow pavement markings adjacent to each lane-use sign, and reposition the exit direction sign over the exit gore point and replace it with one that shows two exit only arrows.  To me, this is a lot more signs/markings for the DOT to maintain, there is additional signs which could contribute to sign clutter, and the exit direction sign is now potentially misleading.  In my view, none of the new MUTCD standards show adequate overhead signing for this common condition except arrow-per-lane signing, which would be an excessive amount of signing for how often this kind of exit configuration is used.

I am in complete agreement with Roadfro on this one.  California also extensively uses the white-on-green down arrow to indicate an option exit lane on advance exit signs.  To omit the green-on-white down arrow will invariably confuse drivers into thinking the upcoming exit has only one lane when in fact it has multiple lanes. IMO, pavement markings and small white roadside signs are not a suitable replacement.  I can easily see Caltrans reinstating the use of the green-on-white down arrow in their supplement. 

I also believe you will never see the "arrow-per-lane" diagrammatic signs in California.  Taking one of the examples in the PowerPoint file I was able to estimate that these signs are at least 14 feet tall assuming the interstate shield is 36 inches high.  If my estimation is correct, then all existing sign bridges in use by Caltrans cannot handle signs that large.  In fact the largest guide sign in California's spec is 138 inches (11.5 feet) although most overhead guide signs are in the 8-10 foot range and that includes the exit number.  I suspect that Caltrans will make the arrow-per-lane purely optional even on new construction.

[Mergingtraffic]

[quote author=J
On a related topic, I don't agree with some of the new standards relating to multilane exits/splits.  I noticed that many figures are now revised to show exit direction signs placed directly above the exit's theoretical gore, where previously such signs were placed slightly ahead of this point. With the revised designs, this sometimes results in signs that indicate two exit only lanes when there really is one exit only lane and one optional lane.  This seems to me to have the potential to confuse drivers about the exit conditions in certain situations.

A specific problem I have is that the new standards prohibit the way Nevada DOT regularly marks exits multilane exits.  Generally, an exit with a drop lane and an option lane will be marked with a green-on-white down arrow over the option lane a black-on-yellow down arrow over the drop lane on the advance sign, followed by an exit direction sign with appropriate up arrows.  This signage would be used at any exit with an option lane, not just those where a route splits.  

However, FHWA believes that drivers misinterpret the green-on-white down arrow as a dedicated lane, prompting excessive/unwarranted lane changes.  Thus, their solution is to prohibit this signing method in favor of this: replacing the advance guide sign with one that shows one arrow for the exit only lane, add at least two regulatory lane-use signs on the shoulder that point out the option lane, add lane control arrow pavement markings adjacent to each lane-use sign, and reposition the exit direction sign over the exit gore point and replace it with one that shows two exit only arrows.  To me, this is a lot more signs/markings for the DOT to maintain, there is additional signs which could contribute to sign clutter, and the exit direction sign is now potentially misleading.  

I agree 100%.  I liked the the white on green arrow for the optional lane and the black on yellow arrow for theexit only lane.  The new way makes it look like both lanes are exit only when in reality there is an optional lane.  This would seem to make drivers change lanes when they don't really have to.
I like this set-up the best: (actually the I-91 SB sign should have 4 down-facing arrows not three...but you get the idea!


Also, the down facing arrows seem to be more exact leaving to less confusion.  

I also don't like the striping for the multi-lane/optional lane exits in the MUTCD.  When I see solid white lines I think it could be a shoulder.  I don't see why the broken white lines can't just separate the wat CT has it striped!?!? Also, on the MUTCD manual, before the solid white line for the optional lane split, why are there a series of short white dashes before it.....what does that accomplish!?!
See page 22:
http://mutcd.fhwa.dot.gov/pdfs/2009/part2e.pdf

[jjakucyk]

I guess this issue with the double-lane exit signs comes out of them requiring all down-pointing arrows to point straight down, with no angled arrows allowed anymore.  The arrow must also be over the center of the lane, so it's no longer possible to have two different signs pointing to the same lane.  They seem to favor the use of diagrammatic signs to account for this. 

[myosh_tino]

I guess this issue with the double-lane exit signs comes out of them requiring all down-pointing arrows to point straight down, with no angled arrows allowed anymore.  The arrow must also be over the center of the lane, so it's no longer possible to have two different signs pointing to the same lane.  They seem to favor the use of diagrammatic signs to account for this.  

Technically it is possible to have two signs point to the same lane although the arrows won't be "over the center of the lane".  Below is how California has been doing this for years...



There are a total of 6 lanes where this photo was taken.  I-5 occupies lanes 1 thru 4 counting from the left.  The ramp to CA-57 north uses lanes 4 and 5 which makes lane 4 an option lane (I-5 or CA-57).  The ramp to CA-22 west uses lanes 5 and 6 which makes lane 5 an option lane (CA-57 or CA-22) and lane 6 an exit only lane.

[Alps]

I also don't like the striping for the multi-lane/optional lane exits in the MUTCD.  When I see solid white lines I think it could be a shoulder.  I don't see why the broken white lines can't just separate the wat CT has it striped!?!? Also, on the MUTCD manual, before the solid white line for the optional lane split, why are there a series of short white dashes before it.....what does that accomplish!?!
See page 22:
http://mutcd.fhwa.dot.gov/pdfs/2009/part2e.pdf

Solid white lines are absolutely used to separate same-direction lanes that will be parting ways, I don't think that's going to be a matter of confusion.  As for the short white dashes, they let you know that there is a decision point coming up and to make sure you're on the correct side of the line.

[J N Winkler]

On a related topic, I don't agree with some of the new standards relating to multilane exits/splits.  I noticed that many figures are now revised to show exit direction signs placed directly above the exit's theoretical gore, where previously such signs were placed slightly ahead of this point. With the revised designs, this sometimes results in signs that indicate two exit only lanes when there really is one exit only lane and one optional lane.  This seems to me to have the potential to confuse drivers about the exit conditions in certain situations.

I have reservations about this change as well, but to be honest they were not strong enough to have prompted me to comment against it even if I had registered that it was in the offing.  (I let this particular item pass me by because I was focused on the diagrammatics.)  The motivation for this change is a study (NCHRP-funded, I think) which was performed by Jonathan Upchurch and others.  Upchurch et al. found, apparently on the basis of tachistoscope testing, that the arrangement now shown in the MUTCD is more likely to be understood correctly by drivers than the two most common of the existing solutions:  (1) the classic "Lunenfeld and Alexander" treatment with two closely spaced arrows on separate sign panels to indicate an optional lane, and (2) the most popular "non-Lunenfeld & Alexander" solution used in states like California and Texas, with yellow "EXIT ONLY" overlays or bottom panels to set off the dropped lanes.  Previous editions of the MUTCD, up to and including the 2003 edition, had flexible language which allowed both solutions to be used, and also allowed the classic non-L&A approach to be used with pull-through signs without downward-pointing arrows.

Upchurch presented a report on this research at (IIRC) a 2005 meeting of the NCUTCD's Guide and Motorist Information Technical Committee, and they agreed to push for the MUTCD to be revised to require that the "winner" of the tachistoscope study be used for multilane exits with optional lanes.  In their place, I would not have been so quick to agree, for these reasons:

*  Although the new arrangement "won" over the others, it did not win by a sufficiently large margin to justify throwing the others out.  In general, I am highly doubtful that it is even possible to devise an efficient signing arrangement for optional lanes which uses downward-pointing arrows only.

*  As noted upthread, the new arrangement does mislead drivers by hiding the existence of an optional lane until the exit.  The counterargument, of course, is that the drivers who are likely to be misled in this way are outnumbered by those who would make an unnecessary lane change to get out of the optional lane because they interpret the signing to mean the optional lane is, in fact, a dropped lane.  As I see it, the real issue here is that the new arrangement inconveniences drivers who are prepared to deal with optional lanes in favor of preventing unnecessary lane changes by those who aren't.

*  Upchurch's study did not consider some other possible signing arrangements, e.g. one commonly used in Minnesota, Wisconsin, and Texas with one downward-pointing arrow for the optional lane, and a vertical ruled line centered on it which separates the exit and straight-ahead destinations.  This leaves the possibility that these might perform much better than Upchurch's winner, albeit at an added cost in sign panel area.

*  Because Upchurch's winner calls for the exit direction sign to be past the theoretical gore point, in order to avoid its being confused with an exit direction sign for a double lane drop, this reduces the amount of advance notice motorists get of the exit and thus reduces agencies' flexibility with regard to sign size and letter height of legend.

The main reason I don't think it is worth putting up a fight over this particular change is that all of the other solutions using downward-pointing arrows are more or less equally bad, just for different reasons.  I am increasingly of the opinion that the best solution to the optional lane problem uses upward-pointing arrows as now called for in the MUTCD, with stippled-arrow diagrammatics as an useful complement for left exits and unusual geometry.  As long as this is the dominant approach for signing optional lanes, I doubt it makes much difference whether Upchurch's winner is thrown into the mix for exit direction signs.

A specific problem I have is that the new standards prohibit the way Nevada DOT regularly marks exits multilane exits.  Generally, an exit with a drop lane and an option lane will be marked with a green-on-white down arrow over the option lane a black-on-yellow down arrow over the drop lane on the advance sign, followed by an exit direction sign with appropriate up arrows.  This signage would be used at any exit with an option lane, not just those where a route splits.  Here's Google Street View images of a typical application on US 95 north in Las Vegas: Advance guide sign and Exit direction sign

Yup--this is the classic non-Lunenfeld & Alexander approach.

However, FHWA believes that drivers misinterpret the green-on-white down arrow as a dedicated lane, prompting excessive/unwarranted lane changes.

Yup, this is the standard critique.  I agree with it, but I also think it is difficult to address this problem without creating others which are just as bad if not worse.

Thus, their solution is to prohibit this signing method in favor of this: replacing the advance guide sign with one that shows one arrow for the exit only lane, add at least two regulatory lane-use signs on the shoulder that point out the option lane, add lane control arrow pavement markings adjacent to each lane-use sign, and reposition the exit direction sign over the exit gore point and replace it with one that shows two exit only arrows.  To me, this is a lot more signs/markings for the DOT to maintain, there is additional signs which could contribute to sign clutter, and the exit direction sign is now potentially misleading.  In my view, none of the new MUTCD standards show adequate overhead signing for this common condition except arrow-per-lane signing, which would be an excessive amount of signing for how often this kind of exit configuration is used.

Those are all valid criticisms of the new approach, especially the potential for sign clutter from the added regulatory & warning signing and the pavement markings.  And it is certainly true that arrow-per-lane signing adds grossly both to message loading and to sign panel area at service interchanges, especially if you stick rigidly to the idea that each through lane (not just the optional lane) needs its arrow.  My personal solution to this problem, which FHWA seems not to have taken up, would be to allow a separate pull-through sign to be used without arrows (either upward- or downward-pointing), and have just upward-pointing arrows for the optional lane and dropped lane on the advance guide and exit direction signs for the exit destination.  The pull-through sign could even be optionally omitted, as California routinely does at service interchanges with the classic non-Lunenfeld & Alexander scheme.

This particular problem illustrates how a desire to provide positive guidance can often lead to excessive message loading.

I am in complete agreement with Roadfro on this one.  California also extensively uses the white-on-green down arrow to indicate an option exit lane on advance exit signs.  To omit the green-on-white down arrow will invariably confuse drivers into thinking the upcoming exit has only one lane when in fact it has multiple lanes. IMO, pavement markings and small white roadside signs are not a suitable replacement.  I can easily see Caltrans reinstating the use of the green-on-white down arrow in their supplement.

It won't surprise me if that happens.  (BTW, just thought of another problem with the small roadside signs--obscuration by large trucks.)  There are a number of states, e.g. Kansas and Minnesota, which have their own approaches for dealing with optional lanes and I don't think they will rip these out just to comply with the 2009 MUTCD.  Either they will put their own approaches into supplements, or they will put up signs which don't comply, which God knows happens often enough.

I also believe you will never see the "arrow-per-lane" diagrammatic signs in California.  Taking one of the examples in the PowerPoint file I was able to estimate that these signs are at least 14 feet tall assuming the interstate shield is 36 inches high.  If my estimation is correct, then all existing sign bridges in use by Caltrans cannot handle signs that large.  In fact the largest guide sign in California's spec is 138 inches (11.5 feet) although most overhead guide signs are in the 8-10 foot range and that includes the exit number.  I suspect that Caltrans will make the arrow-per-lane purely optional even on new construction.

Actually, Caltrans has at least one arrow-per-lane installation and more have been shown in construction plans for recent projects (e.g. US 50 median barrier job in Sacramento).  I think what will happen is that these just won't be designed precisely as shown in the MUTCD.  Just ranging the shield to the left of the forward destination, instead of above it, would be enough to bring a 14' sign down below the 11' 6" maximum shown in Caltrans G-series specs.

[roadfro]

Regarding down arrows for exits with option lanes:

I agree 100%.  I liked the the white on green arrow for the optional lane and the black on yellow arrow for the exit only lane.  The new way makes it look like both lanes are exit only when in reality there is an optional lane.  This would seem to make drivers change lanes when they don't really have to.
I like this set-up the best: (actually the I-91 SB sign should have 4 down-facing arrows not three...but you get the idea!

The way Nevada does it, the arrows on the Route 20/Airport exit direction sign should be right-upward facing arrows typical at an exit, to clearly indicate the decision point is there.  An identical sign with the down arrows would be placed upstream of the exit.

I guess this issue with the double-lane exit signs comes out of them requiring all down-pointing arrows to point straight down, with no angled arrows allowed anymore.  The arrow must also be over the center of the lane, so it's no longer possible to have two different signs pointing to the same lane.  They seem to favor the use of diagrammatic signs to account for this.  

Technically it is possible to have two signs point to the same lane although the arrows won't be "over the center of the lane".  Below is how California has been doing this for years...



There are a total of 6 lanes where this photo was taken.  I-5 occupies lanes 1 thru 4 counting from the left.  The ramp to CA-57 north uses lanes 4 and 5 which makes lane 4 an option lane (I-5 or CA-57).  The ramp to CA-22 west uses lanes 5 and 6 which makes lane 5 an option lane (CA-57 or CA-22) and lane 6 an exit only lane.

I definitely agree with the angled downward arrows rule, as that does get a bit confusing. But I also agree with the "one arrow per lane" rule, as multiple arrows over a lane can be tough to discern if not done properly.  For the pictured example, the sign assembly can be modified such that the vertical lines separating the messages doesn't extend below the text, with the arrow centered below the vertical line.  This way, there would be exactly six arrows in this instance to match the six lanes provided, and I believe the intent of the shared lane would be clear (although I've never seen a real example of this, so I can only speculate).  I realize this method would probably result in one much larger sign panel instead of the three that appear to be used in this case, but it

For the above photo, Nevada DOT would omit the down arrows on the pull-through sign for I-5 north.  I believe the way the MUTCD was written previously, down arrows were not required on pull-through signs unless the geometry contributed to confusion about which lanes were the through lanes.

[Truvelo]

Regarding the I-5 picture in the last post the arrows clearly make it confusing as to which lane goes where. How about adopting the British practice of using stacked overlapping signs like in this picture which makes it easier to get in the right lane.

In this example there are three routes ahead. To head to the M6 N West, B'ham you would use either of the two middle lanes. This is far clearer than placing signs side by side so the number of arrows don't necessarily coincide with the number of lanes.

[J N Winkler]

For the above photo, Nevada DOT would omit the down arrows on the pull-through sign for I-5 north.  I believe the way the MUTCD was written previously, down arrows were not required on pull-through signs unless the geometry contributed to confusion about which lanes were the through lanes.

Actually, that was true only if the exit involved is not a multilane exit.  The MUTCD never defined what a multilane exit was, so that was left to agency interpretation, within certain parameters.  If you chose a straight Lunenfeld & Alexander approach, anything with optional lanes (i.e., all exits which are not simple exits or single lane drops) is a multilane exit.  If you chose the classic non-Lunenfeld & Alexander approach, an exit with one dropped lane and one optional lane qualified as not being a multilane exit, which allowed you to omit arrows on the pull-through sign, or even to omit the pull-through sign altogether.  Neat!  (Bit sophistical though.)

In the case of the gantry Myosh_tino posted, there is advance guide signing (with downward-pointing arrows) for two upcoming exits at the same gantry, so even if one stretched the non-Lunenfeld & Alexander interpretation of multilane exit to the breaking point, it would still be prudent to provide a pull-through with downward-pointing arrows for I-5 for positive guidance.

[J N Winkler]

Regarding the I-5 picture in the last post the arrows clearly make it confusing as to which lane goes where. How about adopting the British practice of using stacked overlapping signs like in this picture which makes it easier to get in the right lane.

That approach is a fail.  It is hard to read, message loading is too heavy (admittedly this results partly from loose British limits on message loading), the signs plus backing board are very deep, and sign panel area is too large.  This last point is a real killer in the American context with 36" shields.

Signs of this type are seen only on HA infrastructure and are not in TSRGD or even in the official list of nonprescribed drawings.  The situation may have changed recently, but I understand that the DFT Traffic Signs Branch is not particularly keen on this approach and it is unlikely to make it into TSRGD or other official guidance with the possible exception of a series of signing IANs from the HA which are due to be issued at some indefinite future date.

[agentsteel53]

I don't think I could parse "M 42 (S) The S. West (M5)" in the interval I have to approach the sign.

I am figuring M42 south goes that way, and it leads to M5, but then what is "The S. West" - the name of an expressway?  Is that M42 or M5?

[Brandon]

Regarding the I-5 picture in the last post the arrows clearly make it confusing as to which lane goes where. How about adopting the British practice of using stacked overlapping signs like in this picture which makes it easier to get in the right lane.

In this example there are three routes ahead. To head to the M6 N West, B'ham you would use either of the two middle lanes. This is far clearer than placing signs side by side so the number of arrows don't necessarily coincide with the number of lanes.

I agree with JN Winkler on this one.  That sign is very confusing and contains way too much information to process at 70mph, IMHO.  Which way do I use to get to M6 since the lane stripings do no coincide with the sign message?

[J N Winkler]

I don't think I could parse "M 42 (S) The S. West (M5)" in the interval I have to approach the sign.

I am figuring M42 south goes that way, and it leads to M5, but then what is "The S. West" - the name of an expressway?  Is that M42 or M5?

"The S. WEST" is an abbreviation for "The SOUTH WEST."  The full phrase (including "The," and "SOUTH WEST" as a fully capitalized open compound) is what is known as a regional destination.  The function is somewhat similar to that of control cities in the US, except that they are intended to imply given regions of the country, and therefore directions of travel, rather than point destinations.  Regional destinations used to appear in initial caps only but that changed with TSRGD 1994.  There is a list of approved regional destinations which has changed from time to time--e.g., "The Lakes" is no longer a regional destination.

From Birmingham (where this sign is located) the M5 is the route to the South West, which includes Devon, Cornwall, etc.  Another regional destination commonly seen on signs is "The NORTH WEST," which refers to the heavily industrialized part of England around Manchester and Liverpool (Cheshire, Lancashire, etc.) which has a particularly dense motorway network and is sometimes called "motorway country" as a result.

[Truvelo]

The signs may be cluttered and heavily abbreviated but what I was getting at is the positioning of them makes sense as to which lane you have to be in. The California example is flawed because it gives the impression of there being 8 lanes rather than 6.

The striping is like that because the two left lanes diverge.

[agentsteel53]

"The S. WEST" is an abbreviation for "The SOUTH WEST."  The full phrase (including "The," and "SOUTH WEST" as a fully capitalized open compound) is what is known as a regional destination.

oh, gotcha.  I figure seeing more signs like that I'd get the hang of it at motorway speeds after the third or fourth one!  

knowing that, I think I could manage with that sign - also, I'd need to confirm that the M5 in parentheses means "to M5"

In a minute I will make a new topic for lane signing, which seems to have taken over a general discussion of the 2009 MUTCD

[roadfro]

In all my reviews of the proposed MUTCD, I don't think I saw figures which depicted the changes I disagree with regarding the optional lanes.  Had I seen them, I definitely would've made some citizen comments.  Nevada adopts the newest MUTCD automatically without supplement,* so this will have wide-ranging effects on the numerous option-lane exits in the state.

Don't get me wrong here. I do think the "arrow-per-lane" signs are far superior to diagrammatics in many instances. I believe they would be much easier to interpret than trying to figure out what lane to be in based on the tiny stipples in the diagrammatic arrow. These work great for system interchanges, especially where an option lane is involved.  They created a solution intended to solve problems relating to diagrammatic signs, but the implementation affects situations where diagrammatics aren't required--specifically at service/local interchanges where "arrow-per-lane" signs at service interchanges are overkill.  And as JN mentioned, the changes to signing intermediate service interchanges provides some positive benefits for one type of driver but negatively impacts others (consider myself one of those negatively impacted).

The revised interpretation of a down arrow over an optional lane is really the issue here. No mention was made of this in the earlier presentation notes regarding the proposed MUTCD changes, nor did I see it in the register notice.  If the changes relating to down arrows was indeed prompted by a study, I wonder why FHWA didn't mention it at all with the changes--cause they cited several studies in relation to other changes in the manual.  I would be genuinely interested in reviewing Upchurch's study, especially to review what signing arrangements were considered in the study.  If this study's proposals didn't garner overwhelming support, I don't understand the justification for including this as the only allowable signing method for service interchanges.


* Nevada has had a standard sign supplement, but not a full MUTCD supplement.  Many new MUTCD standard signs are from the Nevada sign supplement--these include several animal warning signs, signs relating to daytime headlight sections, and signs relating to slow vehicle turnouts.

[agentsteel53]

The signs may be cluttered and heavily abbreviated but what I was getting at is the positioning of them makes sense as to which lane you have to be in. The California example is flawed because it gives the impression of there being 8 lanes rather than 6.

The striping is like that because the two left lanes diverge.

I agree there is some merit to that, though the "double-decker" configuration may not be ideal, especially for US audiences who are absolutely not used to looking up like that to receive further information.

[agentsteel53]

okay, topic has been split.

[roadfro]

J N, I appreciate how you always have detailed and insightful posts relating to sign design.  You often cite studies and guidelines pertaining to guide sign designs.  Would you happen to know where one could find the "Lunenfeld and Alexander", the Upchurch study, or similar guides may be found (online or elsewhere)?  I think this would be of interest to many of the folks here, myself included.



EDIT: I found a PowerPoint presentation about the Upchurch study http://cms.transportation.org/sites/scote/docs/2004meeting/presentations/Upchurch.pdf (1 MB+), given at a ITE meeting. In the example pictures at the beginning, the Warm Springs Road and Sunset Road/McCarran Airport signs are Nevada installations on I-215 EB in Las Vegas. (The Warm Springs sign at the gore is atypical, and would normally have upward arrows; the Airport example uses an incorrect down-arrow type for the upward arrow.)

Without having full details, it seems some of the participants' verbal responses don't favor type 3 (the method Nevada uses), but the simulation results indicate they actually did adequately or better with it compared to some alternatives. I'm not convinced, but maybe I'd change my tune if I can actually read the full study.

[J N Winkler]

Roadfro--thank you for the kind words and for bringing your own thorough approach to these threads.

In regard to citations:

*  "Lunenfeld & Alexander" refers to a 1976 FHWA report, written by Harold Lunenfeld and Gerson Alexander, entitled Signing treatments for interchange lane drops.  What I call the "Lunenfeld & Alexander treatment" is essentially what their report recommends for lane drops with optional lanes.  It has been used as the basis for MUTCD figures from 1978 to 2003.

*  It seems GMITC made the decision to push the Upchurch recommendations at their meeting on January 5, 2005:

http://tcd.tamu.edu/documents/gmitc/010505_GMI_Mtg_Minutes.doc

The main GMITC meeting minutes and agenda papers page is here:

http://tcd.tamu.edu/documents/gmitc/gmitc.htm

*  Upchurch's findings were published by TRB, but unfortunately full text is not freely available:

http://trb.metapress.com/content/g630862h080726w1/

This PDF'd PowerPoint presentation from a FDOT design conference held in 2006 gives an idea of the findings:

http://www.dot.state.fl.us/structures/DesignConf2006/Presentations/session57/Final-57Behzadi.pdf

The research was done under NCHRP project number 20-7(155) and I think at some point a précis of the findings was put online, but I am having no luck finding it.

Now that you mention it, I don't really remember anything like what Upchurch suggested being in the proposed MUTCD text or figures, so it may be worth searching the comments on Regulations.gov to see if GMITC weighed in on this particular issue.

P.S.  If you hate Clearview and are looking for an opportunity to spit nails, this is for you:

http://tcd.tamu.edu/documents/gmitc/Marty_Presentation_NCUTCD_6-09.pdf

[roadfro]

Thanks for the info. I'll have to check some of this out later on...I've been on this forum for the last two hours when I should've been packing to drive down to Vegas for the holidays.

P.S.  If you hate Clearview and are looking for an opportunity to spit nails, this is for you:

http://tcd.tamu.edu/documents/gmitc/Marty_Presentation_NCUTCD_6-09.pdf

I took a quick look at this.  I'm not in the camp of roadgeeks that abhors Clearview. A lot of the non-guide signs in there that are redone in Clearview are quite awful looking though...

The principles of guide sign design in that presentation though actually make a lot of sense, and would seem to result in more aesthetically pleasing signs in several instances. Also, the bicycle symbol with the rider would seem to be simpler and convey the message a bit better.

[J N Winkler]

It's easy to get distracted by these kinds of issues--I'm at home right now, so no packing to do, but I had meant to write a script to draw borders around signs with 20" lettering, and to get camera copies of some old documents I have sitting around.  So much to do!

I don't actually disagree with the idea of having a fully scalable sign design system, since that is essentially what Britain has and it works very well.  I don't agree with the specific proposals though.  Ranging arrows to the right of the shield & cardinal direction word (above the text legend) just looks cludgy to me, and if they are so set on following British practice, they would have done well to use sentence case instead of Initial Caps for their reformed regulatory signs.

[Scott5114]

That presentation seems to have been created by someone more into visual design than highway signage. Note the recommendation of blue for bike guide signage...

[Truvelo]

Here's something else I don't like. These signs suggest that to stay on I-70 you should move over to the left lane as the middle lane is for PA-906. A better option would be for the middle sign to have NEXT RIGHT or similar.