Arrow-Per-Lane (APL) signs

[SignBridge]

There shouldn't be two down arrows over one lane on a pull-thru sign. It should be one arrow per lane. If that situation exists it's probably a design error which is a different issue.

[jakeroot]

There shouldn't be two down arrows over one lane on a pull-thru sign. It should be one arrow per lane. If that situation exists it's probably a design error which is a different issue.

Sorry, not written well. I meant situations where there is a pull-through adjacent to an exit sign. Here is my edited sentence:

If there is a pull-through sign in addition to an exit sign, there might be two arrows over one lane, which could be interpreted as either two adjacent lanes, or a single lane that goes two ways, depending on how well placed the signs is are.

[SignBridge]

Okay jakeroute; sorry I did misunderstand you the first time. Got your correct meaning now.

[roadfro]

Correct, APL signs were created specifically to address the alleged problem created by the FHWA re: option lanes. And I say this because I never had a problem understanding the display of two arrows over an option lane on separate signs for different routes. I've always felt the FHWA created a problem where there wasn't one.

I don't quite agree with the bold line. The MUTCD must be a flexible set of standards that can reflect changing driver behavior, rather than dictating what drivers have to learn and adapt to. If the FHWA senses that any part of the manual is being continuously misunderstood, even in small numbers, it should be their responsibility to craft a better solution.

My issue with white-on-green down arrows is that they mean different things depending on the context: on a pull-through sign, they are a mandatory movement. On an exit sign, they are an optional movement. Sometimes they are used over an exit-only lane that appears only briefly before an exit. If there is a pull-through sign in addition to an exit sign, there might be two arrows over one lane, which could be interpreted as either two adjacent lanes, or a single lane that goes two ways, depending on how well placed the signs is are.

*edited for clarity

I kinda get where FHWA was coming from with this change. If you're gonna have arrows over each lane at the bottom of a sign, it makes sense to have one arrow per lane.

At the same time, in "fixing" the problem with down arrows, the FHWA created another problem in marking option lanes as "exit only" at the actual point of exit. They tried to mitigate this by moving the location of the actual signs further downstream (from ahead of the theoretical gore point to to that point or the actual gore) so that the option lane has already exited at the point of the sign. But this approach created other issues with seeing "exit only" marked over two lanes instead of one, which goes against the driver expectation based on what information given upstream on advance signage showing one exit only lane. I don't know of any entities that used this scheme prior to its adoption in the 2009 MUTCD, nor am I aware of FHWA having done any study or testing of it. Thus it seems like this scheme is a new traffic control method that was introduced without any field testing–a somewhat unusual result given that most new things to the MUTCD don't make it in there without some kind of official experimentation process or study. (Although I'm not sure how much testing APLs got either, to be honest.) The fix was supposed to solve apparent driver confusion issues, but the solution crafted isn't exactly better and introduces its own issues.


I wish FHWA would have adopted an approach of having the option lane arrow indicated on the exit direction sign with white on green (as has been common in Nevada and many other western states, in what I believe is sometimes referred to by forum member J N Winkler as the "non-Lunenfeld & Alexander" approach), even if the new standard disallowed the drop arrow on the advance sign. That would've been less ambiguous and still convey a similar message that 2009 MUTCD was trying to achieve. And would have kept a signing practice already widely in use (even if that practice hadn't been specifically outlined in the manual previously).

[US 89]

At the same time, in "fixing" the problem with down arrows, the FHWA created another problem in marking option lanes as "exit only" at the actual point of exit. They tried to mitigate this by moving the location of the actual signs further downstream (from ahead of the theoretical gore point to to that point or the actual gore) so that the option lane has already exited at the point of the sign. But this approach created other issues with seeing "exit only" marked over two lanes instead of one, which goes against the driver expectation based on what information given upstream on advance signage showing one exit only lane. I don't know of any entities that used this scheme prior to its adoption in the 2009 MUTCD, nor am I aware of FHWA having done any study or testing of it. Thus it seems like this scheme is a new traffic control method that was introduced without any field testing–a somewhat unusual result given that most new things to the MUTCD don't make it in there without some kind of official experimentation process or study. (Although I'm not sure how much testing APLs got either, to be honest.) The fix was supposed to solve apparent driver confusion issues, but the solution crafted isn't exactly better and introduces its own issues.

In my opinion, the even bigger problem than introducing a second "exit only" lane at the point of exit, is the lack of any advance overhead signage for an option lane. This causes drivers intending to exit to scramble to shift into the far right "exit only" lane, thinking that's the only lane that exits (a configuration which is not uncommon!). I just don't see how a signage pattern that results in a lot of panicky lane changes can be a good thing.

I am aware that the MUTCD does have those small white signs on the right indicating an option lane is approaching. But let's be real. In an urban setting, there is often way too much traffic for the unfamiliar driver to be in tune with small white regulatory signs like that. Especially when the vast majority of those regulatory signs on urban freeways are things like "No vehicles towing trailers in left lane" or "Move accident vehicles to next exit" and other things of the like. Those are always "reminder" type signs that may not even apply to average Joe in a car, not "you need to look at this now to know where to go".

[SignBridge]

So like I said earlier, even if FHWA  didn't create a problem where there wasn't one, their solution actually created more problems than it solved, if in fact there even was a problem to begin with.

Or to put it another way: the cure is worse than the disease (if any).

[lordsutch]

I still think FHWA erred in not adopting Ontario-style APL signs as an option (no pun intended) for less significant interchanges that drop an auxiliary lane, which I think would have resolved a lot of the problems with downward arrows and stippled arrows more simply, saving the full-blown APL treatment for major freeway-to-freeway splits and the like.

[jakeroot]

I still think FHWA erred in not adopting Ontario-style APL signs as an option (no pun intended) for less significant interchanges that drop an auxiliary lane, which I think would have resolved a lot of the problems with downward arrows and stippled arrows more simply, saving the full-blown APL treatment for major freeway-to-freeway splits and the like.

Partial APLs, in the style of that used in Ontario, are actually becoming quite common. They are not in the MUTCD yet, but I've heard they may be soon.

[jeffandnicole]

So like I said earlier, even if FHWA  didn't create a problem where there wasn't one, their solution actually created more problems than it solved, if in fact there even was a problem to begin with.

Or to put it another way: the cure is worse than the disease (if any).

You're saying that, but motorists understand the APLs and there's little confusion.  I'm not sure where you're thinking these signs create a problem.

[J N Winkler]

FHWA did propose to add sawn-off APLs (which is essentially what the Ontario-style signs are) to the upcoming 11th Edition of the MUTCD.  But that has yet to drop.

[wanderer2575]

FHWA did propose to add sawn-off APLs (which is essentially what the Ontario-style signs are) to the upcoming 11th Edition of the MUTCD.  But that has yet to drop.

A crucial difference is that the Ontario signs show the option lane well in advance, while the MUTCD allows that only for "major" (i.e. system) interchanges.  Is that proposed to change in the next edition?

[jakeroot]

FHWA did propose to add sawn-off APLs (which is essentially what the Ontario-style signs are) to the upcoming 11th Edition of the MUTCD.  But that has yet to drop.

A crucial difference is that the Ontario signs show the option lane well in advance, while the MUTCD allows that only for "major" (i.e. system) interchanges.  Is that proposed to change in the next edition?

I believe the partial ('sawn off') APL is specifically for non-system interchanges where a full-blown APL is potentially not necessary, and is meant as a replacement for the down arrow signage no longer permitted.

[J N Winkler]

FHWA did propose to add sawn-off APLs (which is essentially what the Ontario-style signs are) to the upcoming 11th Edition of the MUTCD.  But that has yet to drop.

A crucial difference is that the Ontario signs show the option lane well in advance, while the MUTCD allows that only for "major" (i.e. system) interchanges.  Is that proposed to change in the next edition?

I believe the partial ('sawn off') APL is specifically for non-system interchanges where a full-blown APL is potentially not necessary, and is meant as a replacement for the down arrow signage no longer permitted.

Yes--as Jake says, the sawn-off APL is to be available for minor and intermediate interchanges.  But the proposed figures suggest that FHWA also wants to retain the "hide the option lane" approach of the 2009 MUTCD as an option.

Here are the relevant figures positioned side by side:

[SignBridge]

So like I said earlier, even if FHWA  didn't create a problem where there wasn't one, their solution actually created more problems than it solved, if in fact there even was a problem to begin with.

Or to put it another way: the cure is worse than the disease (if any).

You're saying that, but motorists understand the APLs and there's little confusion.  I'm not sure where you're thinking these signs create a problem.

If there are no problems with APL signs, then what are we all discussing here?

The problem that I find is conventional signing with standard down arrows, including with two arrows for different routes over one lane, was easier to visually read and understand than APL signs that are so huge with the legend all over the place instead of simply boxed on smaller signs in conventional signing.

[wanderer2575]

If the proposed changes allow option lanes on "sawn-off" APLs for all interchanges, that can only be a good thing.  It's ridiculous that "hide the option lane" is still retained as allowable.  The whole purpose of signing is to provide clear guidance to drivers, so it's absurd to deliberately omit such information.  In the case of Figure 2E-48 (the figure on the right) and I intend to turn left at the top of the ramp, I'd like to know in advance that I should use the option lane to put myself in the left lane of the ramp, rather than seeing -- surprise! -- that having put myself in the exit-only lane I now have to make a lane change on the ramp within a shorter distance.

[SignBridge]

If the proposed changes allow option lanes on "sawn-off" APLs for all interchanges, that can only be a good thing.  It's ridiculous that "hide the option lane" is still retained as allowable.  The whole purpose of signing is to provide clear guidance to drivers, so it's absurd to deliberately omit such information.  In the case of Figure 2E-48 (the figure on the right) and I intend to turn left at the top of the ramp, I'd like to know in advance that I should use the option lane to put myself in the left lane of the ramp, rather than seeing -- surprise! -- that having put myself in the exit-only lane I now have to make a lane change on the ramp within a shorter distance.

JeffandNicole, this is another of the problems I'm talking about created by APL signing.

[jeffandnicole]

So like I said earlier, even if FHWA  didn't create a problem where there wasn't one, their solution actually created more problems than it solved, if in fact there even was a problem to begin with.

Or to put it another way: the cure is worse than the disease (if any).

You're saying that, but motorists understand the APLs and there's little confusion.  I'm not sure where you're thinking these signs create a problem.

If there are no problems with APL signs, then what are we all discussing here?

Because we discuss everything on these forums.

The problem that I find is conventional signing with standard down arrows, including with two arrows for different routes over one lane, was easier to visually read and understand than APL signs that are so huge with the legend all over the place instead of simply boxed on smaller signs in conventional signing.

It's been pointed out that providing two arrows over one lane, from a distance, can make it appear there are two separate lanes.

Doing a quick perusal of the web, it's noted by numerous publications, both state and private research, that states APL signage (the feds actually term them OAPL: Overhead Arrow Per Lane) research concluded the signs offer clear benefits to motorists.  Coming upon this site: https://rosap.ntl.bts.gov/view/dot/67028 , it suggests research that goes back to 1992 showing one arrow per lane is beneficial. 

The first paragraph on page 2 of that report reads:

Previous research suggested that overhead signs with specific lane assignment information better support driver decisions and lane choice at interchanges than diagrammatic guide signs. The use of an individual arrow for each lane on guide signs is more effective in communicating lane assignment information than a graphic view of the entire roadway lane assignment displayed in one arrow (Brackett et al. 1992). Furthermore, drivers readily understand the relationship between specific lanes and corresponding destinations displayed by overhead signs with specific lane assignment information (Richard and Lichty 2013). Golembiewski and Katz (2008) found that drivers made significantly more correct lane choices and comprehended a sign configuration showing one arrow per lane compared to diagrammatic signs. Fitzpatrick et al. (2013) also found that OAPL signs were superior for helping drivers make correct lane choices compared with diagrammatic signs.

Further on page 3, it references the following:

Results found that every driver correctly exited when shown an OAPL sign, and slightly more than one-third made an unnecessary lane change.

The unnecessary lane change reflects that motorists were more likely to utilize the 'Exit Only' lane vs the option lane, however as shown in the first sentence, the testers were able to, at a minimum, correctly exit the highway.

The more common criticism of the signage is mentioned further down, which is the size and cost of the signage.

The more recent studies, which that report is really about, along with others including this one ( https://highways.dot.gov/research/projects/evaluation-additional-alternative-arrow-types-and-sizes-overhead-arrow-lane-oapl ) is for partial width OAPL.

Now, you're going to say that this is due to trying to solve a problem that didn't exist.  But studies showed that there was a problem that did exist, although it may not have for you.  Signage continues to evolve.  The signage you prefer isn't the first signage that was used for exits and option lanes.  They came out overtime, after previous versions were found to be confusing.  And enough confusion still exists for many drivers that they wanted to come out with something else.   Remember - even the common STOP sign wasn't perfected on try number 1 - many of them used to be yellow at first.

[wanderer2575]

If the proposed changes allow option lanes on "sawn-off" APLs for all interchanges, that can only be a good thing.  It's ridiculous that "hide the option lane" is still retained as allowable.  The whole purpose of signing is to provide clear guidance to drivers, so it's absurd to deliberately omit such information.  In the case of Figure 2E-48 (the figure on the right) and I intend to turn left at the top of the ramp, I'd like to know in advance that I should use the option lane to put myself in the left lane of the ramp, rather than seeing -- surprise! -- that having put myself in the exit-only lane I now have to make a lane change on the ramp within a shorter distance.

JeffandNicole, this is another of the problems I'm talking about created by APL signing.

On the contrary, this is a problem created by a lack of APL signing when there is an option lane.

[SignBridge]

If the proposed changes allow option lanes on "sawn-off" APLs for all interchanges, that can only be a good thing.  It's ridiculous that "hide the option lane" is still retained as allowable.  The whole purpose of signing is to provide clear guidance to drivers, so it's absurd to deliberately omit such information.  In the case of Figure 2E-48 (the figure on the right) and I intend to turn left at the top of the ramp, I'd like to know in advance that I should use the option lane to put myself in the left lane of the ramp, rather than seeing -- surprise! -- that having put myself in the exit-only lane I now have to make a lane change on the ramp within a shorter distance.

JeffandNicole, this is another of the problems I'm talking about created by APL signing.

On the contrary, this is a problem created by a lack of APL signing when there is an option lane.

J&N, you're right about your last point. That issue about how to sign option lanes with conventional signing is a actually a case of poorly thought out configuration by the FHWA in the 2009 Manual. So I stand corrected on that one. It's not an OAPL problem.

But I stand by my general viewpoint on OAPL's. In my personal opinion, all those studies that you cited show is that different drivers react differently to different forms of visual graphics.

[SignBridge]

FHWA did propose to add sawn-off APLs (which is essentially what the Ontario-style signs are) to the upcoming 11th Edition of the MUTCD.  But that has yet to drop.

A crucial difference is that the Ontario signs show the option lane well in advance, while the MUTCD allows that only for "major" (i.e. system) interchanges.  Is that proposed to change in the next edition?

I believe the partial ('sawn off') APL is specifically for non-system interchanges where a full-blown APL is potentially not necessary, and is meant as a replacement for the down arrow signage no longer permitted.

Yes--as Jake says, the sawn-off APL is to be available for minor and intermediate interchanges.  But the proposed figures suggest that FHWA also wants to retain the "hide the option lane" approach of the 2009 MUTCD as an option.

Here are the relevant figures positioned side by side:

Sawn-off APL's of the style shown in the MUTCD proposal above are already in use in some places. Notably on New Jersey's Garden State Pkwy. Northbound at Exits 142 B-C, just north of the Union Toll Plaza (if it's still there LOL)