AARoads Forum

 :sombrero:
Should I-19 BGS Stay metric or be replaced with standard Or Both On BGS?

Metric should stay, however I think that Both Metric and Standard measures should be displayed.
:sombrero:

Stay metric- it is funny, living down here a lot of people think the reason for the metric signs is "so the Mexicans will know what's going on'" and they should be changed because of that.

I like it- since I pay attention to mileposts to determine how far I  have to go, driving I-19 feels much faster than driving any mileage-based road, because I see posts 1.62 times as often.

The novelty is cool though.

Stay metric... and convert I-17 and while they're at it...

The unit of measure in the US is standard so why should this interstate be signed metric?
The other interstates that begin/end at the Mezican border aren't signed metric, are they?
I could live with both standard and metric being displayed for a few hundred miles to aid our "southern neighbours".

My answer is "yes"  :sombrero:

QuoteI could live with both standard and metric being displayed for a few hundred miles to aid our "southern neighbours".

The problem is that that's not and never was the point- I agree that we don't do it just to help Mexicans navigate, that's stupid. The freeway was signed that way because Arizona believed we'd be going metric very shortly. As it stands, it's a unique anomaly- anomalies are cool

Quote from: allniter89 on December 08, 2011, 12:57:26 PMThe unit of measure in the US is standard so why should this interstate be signed metric?

Touristic interest.

QuoteThe other interstates that begin/end at the Mexican border aren't signed metric, are they?

No.  There is limited use of bilingual and dual-unit signing on I-5 at San Ysidro and I-35 at Laredo.  (I-19 used to have some bilingual signing as well as metric-unit signing; the bilingual signs, which were mainly for tourist information, were installed in the 1981 metric signing contract but removed as part of the 1998 sign refurbishment.  The 1998 refurbishment did not add any new signs with the lone exception of a Spanish translation of "NO FIREARMS OR AMMO.")

Examples of the 1981 bilingual signing on I-19:

(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fwww.sabre-roads.org.uk%2Fgallery%2Falbums%2Fuserpics%2F10050%2Fi-19-signs-page-01.png&hash=84abc08b1566ad033d870fda8f3e1f33dcf441eb)

(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fwww.sabre-roads.org.uk%2Fgallery%2Falbums%2Fuserpics%2F10050%2Fi-19-signs-page-06.png&hash=4f8b7db7d15764e2e9595e052dfc338ce7127a96)

(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fwww.sabre-roads.org.uk%2Fwiki%2Fimages%2F4%2F4d%2FOld-arizona-welcome-sign-spanish.png&hash=0b896c3f085ba0705200874289d35ca075f13eff)

(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fwww.sabre-roads.org.uk%2Fwiki%2Fimages%2Fb%2Fba%2FOld-arizona-welcome-sign-english.png&hash=764400d6b162b1c9a14158803992e248f563bc38)

Bilingual signing as used in 1998:

(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fwww.sabre-roads.org.uk%2Fgallery%2Falbums%2Fuserpics%2F10050%2Fi-19-signs-page-07.png&hash=2d1e1c92e16f3da0d4f8c7547436c04ac9d14f55)

QuoteI could live with both standard and metric being displayed for a few hundred miles to aid our "southern neighbours".

Where I-19 is concerned, my position is fairly simple:

*  Metric signing done according to the design rules in force in 1981, not 1998 (this would actually result in explicit metric units disappearing from a number of signs--primarily distance signs and interchange sequence signs--which now have them)

*  Provision of bilingual signing expanded to match 1981 (including a Spanish-language version of the current copper-star Arizona welcome sign)

*  Reinstatement of metric signing up to the I-10/I-19 wye interchange

*  "Think customary" signing (not currently provided) to make it unambiguous that although distance signing on I-19 (guide signs, exit numbers, distance posts, etc.) is fully metric, speed limits continue to be signed in customary units

*  Complete abandonment of any and all plans to sign I-19 in English units

Where bilingual signing is concerned, my feeling is that the scope for it is not that great on I-19, and that it is better to try to be "multiple language friendly" within existing signing norms by relying more on symbol signs.  Expanded provision of bilingual signing would be controversial not only because it would inflame an anti-immigrant tendency in Arizona that already thinks (incorrectly!) that I-19 was signed in metric to hang out the welcome mat to Mexicans, but also because it could be attacked on message-loading grounds.  There is no strong political constituency in favor of Spanish-language signing in Arizona, let alone one which is sufficiently militant to demand it solely on language parity grounds as in Wales and in Canadian provinces which have compulsory official bilingualism.

Because Arizona has been characterized by very high population growth through the 20th century, it is likely that a majority of current Arizonans were not in the state in 1981 and so do not know that metric signing on I-19 is a leftover of the 1970's metric push rather than, say, a special accommodation to illegal immigrants.  (The high growth rate has caused problems in other contexts as well.  It was a factor in Evan Mecham winning the governorship, and caused Carl Hayden--whose seniority and wheeling-dealing approach made the Central Arizona Project possible--almost to lose elections.)

Anomalies are cool, but if all the button copy is to be replaced, it's time to catch up and go mileage-based again. I feel the same way about DE 1.

I don't think I-19 ever had milepointing and mileage-based exit numbers.

Quote from: allniter89 on December 08, 2011, 12:57:26 PM
The unit of measure in the US is standard so why should this interstate be signed metric?

Because it's cool!

Quote from: deanej on December 09, 2011, 12:46:01 PM

Quote from: allniter89 on December 08, 2011, 12:57:26 PM
The unit of measure in the US is standard so why should this interstate be signed metric?

Because it's cool!

Like pooing!

I think all US highway signs, not just I-19, ought to be converted to metric, but I also recognize it's not likely to happen in my lifetime.

Quote from: NE2 on December 09, 2011, 03:06:23 PM

Like pooing!

what are you talking about?  pooing is shit!

And FUNNY!

Quote from: J N Winkler on December 08, 2011, 07:57:38 PM
I don't think I-19 ever had milepointing and mileage-based exit numbers.

I-19 did/does have milepointing!  It's just that the official mile markers are posted perpendicular to the highway along the boundary fences off the shoulders (if that makes any sense).

IMO, switch back from kilometers to miles.  As much as I prefer the metric system, I'd say the dream of our nation switching over is long gone.  It makes no sense to have one lone highway signed in a different system, especially when speed limits etc. are still posted in miles.

As far as bilingual signing goes, I say let demographics rule that.  If it's needed, then it's needed; if it's not, then it's not.  But I too would much prefer using pictorial symbols as a means of crossing the language barrier.

I am torn as to what to vote for in the poll - while I like the idea of metric signage and think the U.S. should begin the transition to metric as a whole, I feel that doing so JUST with I-19 is detrimental. Conversion should be all-or-nothing. So as long as the other freeways remain non-metric, I-19 should do so as well.

A lot of commenters in this thread seem to have made their decisions on the basis that a local exception to a ruling units scheme is not permissible.  Why not?  If I-19 remains metric while the rest of the Interstate system is signed in customary units, what is wrong with that?

Well, in my opinion, standards are standards for a reason. "Uniqueness" alone should be no reason to purposefully keep a road from conforming to standards. Ideally I would like to see the entire system in metric, but so long as the entire system is in customary units, the ENTIRE system should be.

Quote from: deathtopumpkins on December 12, 2011, 04:59:55 PMWell, in my opinion, standards are standards for a reason. "Uniqueness" alone should be no reason to purposefully keep a road from conforming to standards. Ideally I would like to see the entire system in metric, but so long as the entire system is in customary units, the ENTIRE system should be.

But what standard requires signing in customary units?

Also, it is a well-established fact that conformity to the MUTCD is poorer in some states (and some regions within states) than in others.  Why do metric signs on I-19 merit rectification as a supposed nonconformity, while the well-attested excursions from standard elsewhere don't?

I think the reluctance to allow I-19 to "get away" with having metric has to do with a desire to keep the Interstate System as uniform as possible. A driver sees every other Interstate with standard units, then expects I-19 to have the familiar units seen elsewhere.

That is the point of view I am trying to question.  There is a distinction between standards and practice; as far as I am aware, there is no published standard which requires that guide signing on Interstates be in customary units, although that is the normal practice on the overwhelming majority of Interstate mileage.

We insist that traffic control devices follow uniform standards in order to allow them to be recognized readily as official signs, to allow them to be interpreted and reacted to as quickly as practicable, and to allow drivers to "read" the road reliably and fluently.  I would argue that none of these aims is better served by changing signing on I-19 from metric to customary.  Aside from the different units, it is pretty much plain-vanilla Chapter 2E signing and is processed by drivers in the same way as the signing on any other rural Interstate.  It uses the official typefaces in the officially approved color combinations at the officially approved letter and shield heights.  In fact its conformity to MUTCD prescriptions in this respect is a good bit better than on many other Interstates with the vanilla units treatment.  The "metric push" began almost 40 years ago, and the majority of US drivers have now had a metric education, even if they are not necessarily accustomed to working with metric units in a driving context.  The metric treatment applies only to the guide signing, not to regulatory signs of standardized design (e.g., the 75 MPH speed limit signs), or signs which are definitely safety-critical and have led to documented unit-system-related problems elsewhere (e.g., bridge clearance signs).

There is always an excellent case for conformity to standards whose scope and reach has been fixed with regard to public safety.  Uniformity for uniformity's sake, however, not only is a first cousin to tall-poppy syndrome, but also opens the door to heavy switching costs.

There is actually a significant degree of local opposition to changing signing on I-19 from metric to customary units, not just because of the tourism aspect, but also because businesses in the I-19 corridor have long advertised themselves by proximity to particular exits with km-based numbers.  Arizona DOT's Tucson district was gung-ho about converting to customary units seven years ago, but I think they have since retreated from this position, since draft plans for the upcoming I-19 sign replacement I have seen show every sign with explicit metric units tagged as "retain in place."

Notwithstanding your florid language (you know who you are), I just think all highways should be in English. The MUTCD no longer is written in dual units, although it does contain standards and guidance for signing in metric. I'm not opposed to metric signing, but I think it's confusing to have one roadway in metric and no other ones. If Arizona wants to make a more concerted effort as a state, or at least on Interstates if not all freeways, to provide metric signage, then I would reverse my decision and support Arizona's efforts.

I agree that units are pretty important as far as standards are concerned- the general traveler may not notice the difference in an off-shaped shield or a weird green sign, but different units fundamentally change the driving experience.

Assuming the objective is to have standardized roadways, I agree that English units are the only way to go. I'm not really sure how you argue with a straight face that the general public is more likely to be affected by green signs that are slightly disproportional than an entirely different measurement system.

My desire for metric is selfish- I just like the uniqueness.

Quote from: Steve on December 13, 2011, 10:16:16 PMI'm not opposed to metric signing, but I think it's confusing to have one roadway in metric and no other ones.

Quote from: corco on December 13, 2011, 10:34:58 PMI agree that units are pretty important as far as standards are concerned- the general traveler may not notice the difference in an off-shaped shield or a weird green sign, but different units fundamentally change the driving experience.

But where are all the people that are confused by metric signing?  If you yourself have driven on I-19, can you truthfully say you have been confused by the metric signing?

QuoteI'm not really sure how you argue with a straight face that the general public is more likely to be affected by green signs that are slightly disproportional than an entirely different measurement system.

Lack of conformity goes well beyond instances of signs being "slightly disproportional."  I have seen Interstate guide signs intended for 75 MPH rural contexts with 10 2/3" UC/8" LC primary destination legend (violates MUTCD sizing rules).  Exit numbers on SH 130 in Texas increase in the wrong direction (violates MUTCD rules for progression of distance posts and exit numbers).  We still have holdouts with sequentially numbered exits (violates new MUTCD ban on sequential numbers).  Many states do not use exit numbers on non-Interstate freeways (violates new MUTCD requirement for exit numbers on all freeways).  Need I go on?

QuoteMy desire for metric is selfish- I just like the uniqueness.

I like the metric signs on I-19 and I would like to see them replaced in kind.  But why resort to special pleading when there are perfectly rational arguments that can be made in favor of the current arrangement?  As the only Interstate with metric guide signing in a country where English units rule, I-19 is an anomaly, but we do not have traffic engineering standards merely to eliminate anomalies; instead, we have them to ensure that any which are allowed to exist do not interfere with safety.

Quote from: J N Winkler on December 14, 2011, 12:31:51 AM
Exit numbers on SH 130 in Texas increase in the wrong direction (violates MUTCD rules for progression of distance posts and exit numbers).

If you want to be that anal, we can call it a beltway, in which case the exit numbers increase in the correct direction.

QuoteBut where are all the people that are confused by metric signing?  If you yourself have driven on I-19, can you truthfully say you have been confused by the metric signing?

I wouldn't say I was confused, but I do definitely notice it. I've also got a decent education and a decent amount of experience driving/riding in Canada- I would hazard that to the truly uneducated (high school dropouts and the like), the metric system probably isn't something that is terribly familiar (unless they came from Mexico, which I'll admit a good chunk of the uneducated in southern Arizona do) and could lead to confusion on that level.

QuoteLack of conformity goes well beyond instances of signs being "slightly disproportional."  I have seen Interstate guide signs intended for 75 MPH rural contexts with 10 2/3" UC/8" LC primary destination legend (violates MUTCD sizing rules).  Exit numbers on SH 130 in Texas increase in the wrong direction (violates MUTCD rules for progression of distance posts and exit numbers).  We still have holdouts with sequentially numbered exits (violates new MUTCD ban on sequential numbers).  Many states do not use exit numbers on non-Interstate freeways (violates new MUTCD requirement for exit numbers on all freeways).  Need I go on?

No, but is the general public more likely to notice any of those things or signage that is in kilometers instead of miles? I'd hazard that the latter is a lot more  A) obvious and B) likely to affect their navigation. For instance, a driver unfamiliar with the distance of 1 km could choose to pass a truck before exiting, and then not get into the exit lane in safe time, cutting off the truck and braking. A mis-sized speed limit sign still conveys the same message, and exit number anomalies are likely to be unnoticed by the majority of drivers, and certainly with advance signage any differences would be offset on site.

QuoteI like the metric signs on I-19 and I would like to see them replaced in kind.  But why resort to special pleading when there are perfectly rational arguments that can be made in favor of the current arrangement?  As the only Interstate with metric guide signing in a country where English units rule, I-19 is an anomaly, but we do not have traffic engineering standards merely to eliminate anomalies; instead, we have them to ensure that any which are allowed to exist do not interfere with safety.

The only argument I'd feel comfortable advancing is that they should be grandfathered because they already exist.

Quote from: corco on December 14, 2011, 12:52:35 AMI wouldn't say I was confused, but I do definitely notice it. I've also got a decent education and a decent amount of experience driving/riding in Canada- I would hazard that to the truly uneducated (high school dropouts and the like), the metric system probably isn't something that is terribly familiar (unless they came from Mexico, which I'll admit a good chunk of the uneducated in southern Arizona do) and could lead to confusion on that level.

Maybe--but I am still skeptical.  Aside from the different units system, the progression of advance guide and exit direction signs is pretty plain-vanilla on I-19, and that in itself is a pretty powerful navigational cue.

I-19 is actually the first highway signed in metric I ever drove since I got to it (in 1998) before I started driving in Canada (2001) or Mexico (2002).  I had no difficulty with the metric signing.

QuoteNo, but is the general public more likely to notice any of those things or signage that is in kilometers instead of miles?

Trust me, you will notice it if you are a stranger driver.  "Why can't I read that sign?"  "Why are the exit numbers in the 400's and not going up in the right direction?"  "Passed Exit 1 a while back.  Why is it taking forever to reach Exit 2?"  "What number is the exit I want?  Why don't any of these exits have numbers?"  And so on.  The lack of MUTCD mileposts on California freeways caused me problems the first time I drove in California, believe it or not--far more than I experienced with metric signs on I-19.

QuoteI'd hazard that the latter [metric] is a lot more  A) obvious and B) likely to affect their navigation. For instance, a driver unfamiliar with the distance of 1 km could choose to pass a truck before exiting, and then not get into the exit lane in safe time, cutting off the truck and braking.

I think that scenario is unlikely.  I-19 is km-posted, and exit spacing is wide enough that a driver unfamiliar with kilometers (and who could be expected to be more alert to cues provided by distance posts because of that lack of familiarity) would have enough opportunity to learn how long a km is before he had to decide whether to overtake a truck.  Also, passing within 1 km of an exit means initiating the maneuver when an advance guide sign is in sight, which is always dicey--no matter what the unit system is--when you don't know the road but do know you want to take the upcoming exit.

Plenty of reckless people would attempt overtakes at 1 km distance from the exit they intend to take, but I don't think the units system would be a factor of any importance in that decision.  (Overtaking at 1 km is more or less the same as overtaking at 1/2 mile.)

Quote

QuoteI like the metric signs on I-19 and I would like to see them replaced in kind.  But why resort to special pleading when there are perfectly rational arguments that can be made in favor of the current arrangement?  As the only Interstate with metric guide signing in a country where English units rule, I-19 is an anomaly, but we do not have traffic engineering standards merely to eliminate anomalies; instead, we have them to ensure that any which are allowed to exist do not interfere with safety.

The only argument I'd feel comfortable advancing is that they should be grandfathered because they already exist.

I would not feel comfortable pushing that argument at all.  First, it runs out of road when the sheeting on the current I-19 signs wears out, a circumstance which will be at hand in probably another 10 years.  (The pending partial replacement in my view is somewhat premature, though I don't have access to any retroreflectivity measurements Arizona DOT may have done to justify it.)  Second, when equitable interests are not being protected (e.g., an investment in obsolete components of excess durability--California and porcelain enamel come to mind), it is a pretty poor defense for something that is a bad idea in the first place.

Quote from: J N Winkler on December 14, 2011, 12:31:51 AM
Lack of conformity goes well beyond instances of signs being "slightly disproportional."  I have seen Interstate guide signs intended for 75 MPH rural contexts with 10 2/3" UC/8" LC primary destination legend (violates MUTCD sizing rules).  Exit numbers on SH 130 in Texas increase in the wrong direction (violates MUTCD rules for progression of distance posts and exit numbers).  We still have holdouts with sequentially numbered exits (violates new MUTCD ban on sequential numbers).  Many states do not use exit numbers on non-Interstate freeways (violates new MUTCD requirement for exit numbers on all freeways).  Need I go on?

Heck, look at the state of California... no numbered exits until the early 2000's, exit tabs incorporated into the guide sign (i.e. no external tabs), cutout US route shields, cutout and non black and white route shields, undersized exit "tabs", no reference markers (mileposts) and on and on.  Given the fact that a vast number of signs now violate the 2009 MUTCD, look for the lack of conformity to skyrocket in the Golden State (arrow-per-lane signs? Pfft, yeah right!)

As far as I-19 is concerned, I say leave it metric.  As much as I don't care for the metric system, I-19 has existed this long with metric units without a major outcry from the general public so I don't see what all the hub-bub is all about.

Yeah, I imagine CA won't ever have arrow-per-lane signs... there's no way they'd stand up to the high wind loads unique to CA that prevent them from having tabs!

Quote from: Steve on December 13, 2011, 10:16:16 PMI just think all highways should be in English.

So the correct spelling of 'through'? that would cost a lot to change. Not to mention using yards, and feet only being on height and weight restriction signs, and metric tons for weight limits (plus Celsius for temperature if that comes up)...

I think you meant American, rather than English :P

As you can see from the above, I can be pretty anal retentive, but I-19 (or if some road in the UK was signed in metric) doesn't bother me. It's a little quirk that makes life interesting, much like how we still use miles, etc on the road in the UK despite almost everything else being officially metric and all the nations around us being metric.

QuoteTrust me, you will notice it if you are a stranger driver.  "Why can't I read that sign?"  "Why are the exit numbers in the 400's and not going up in the right direction?"  "Passed Exit 1 a while back.  Why is it taking forever to reach Exit 2?"  "What number is the exit I want?  Why don't any of these exits have numbers?"  And so on.  The lack of MUTCD mileposts on California freeways caused me problems the first time I drove in California, believe it or not--far more than I experienced with metric signs on I-19.

You might be able to convince me that people who are used to mileage based exits would notice sequential exits, but I'd bet the majority of travelers neither realize nor care that exits increase from south to north and west to east- certainly not enough to notice a difference.  A lack of exit tabs could be weird when you're used to navigating by exit number, but it's not something that could pose a safety threat.

A driver misjudging the distance of a kilometer could- it's unlikely, but it could actually pose a safety threat. A driver that doesn't know how far a kilometer is or mistakes it for a mile could very well make distance-based decisions that are dangerous. Just because you or I wouldn't doesn't mean that it couldn't happen.

You have to remember that roadgeeks are not standard travelers. The experience you or I or pretty much anybody reading this forum have driving down the road  is not a very good representation of what the actual traveler notices or cares about. Our experiences are nearly irrelevant, because we're trained to be hyper-astute to anomaly. Even if you're optimistic- say 75% of travelers notice and are aware of things like exit numbers and their function (I'd say that 75% is optimistic for being aware of how exit numbers are supposed to work), that leaves a full 25% of travelers who don't. That's a very significant number.

But I'd bet nearly 100% of travelers notice when things are posted in metric, and some of those have little idea how metric units play out over space.  I'd say that once again, the roadgeek brain seems to be a lot more spatially aware than the average bear- so your ability to adapt to a kilometer instead of a mile is probably a lot better than the general populus.

QuoteI would not feel comfortable pushing that argument at all.  First, it runs out of road when the sheeting on the current I-19 signs wears out, a circumstance which will be at hand in probably another 10 years.  (The pending partial replacement in my view is somewhat premature, though I don't have access to any retroreflectivity measurements Arizona DOT may have done to justify it.)  Second, when equitable interests are not being protected (e.g., an investment in obsolete components of excess durability--California and porcelain enamel come to mind), it is a pretty poor defense for something that is a bad idea in the first place.

Oh- I'm not advocating never replacing the signs, but I think an argument can be (and has been) made that you could replace the current signs with metric units simply because the old ones are and the difficulty in adjusting wouldn't be worth the gains from changing (You could argue the same thing with sequential exits).

One thing that does need to happen regardless is consistency in units- the border checkpoint signs, for instance, are in standard units, as are call box signs.

As far as reflectivity- the southbound are mostly OK, but some of the northbound signs are in pretty bad condition.

Quote from: corco on December 13, 2011, 10:34:58 PM
....

My desire for metric is selfish- I just like the uniqueness.

My preference that all signs be metric is based on the fact that I understand that system a lot better than the gibberish that predominates in the USA. All the bizarre conversions involving inconsistent amounts like 12s, 16s, 8s, 5280s, etc., simply don't make any sense to me.

Quote from: corco on December 14, 2011, 04:07:29 PMYou might be able to convince me that people who are used to mileage based exits would notice sequential exits, but I'd bet the majority of travelers neither realize nor care that exits increase from south to north and west to east- certainly not enough to notice a difference.

I don't think that is necessarily true.  Information about progression of exit numbers appears in materials geared to lay audiences and it is something that becomes very obvious to people studying maps to plan long-distance roadtrips.  It is the kind of information you can expect to see in AAA TripTiks, for instance, which are not designed for roadgeeks by any stretch of the imagination.

I was not a road enthusiast in any meaningful sense when I started driving long-distance, but the correspondence between exit numbers and mileposts and the progression of milepointing from south to north and west to east was something I noticed early on.

QuoteA lack of exit tabs could be weird when you're used to navigating by exit number, but it's not something that could pose a safety threat.

By itself, probably not--but for drivers who expect that guidance to be provided and find it absent, it contributes to disorientation, which in turn can be a contributing factor in a crash.  For example, the lack of exit numbers and a relatable distance-posting system on I-10 in California made it difficult for me to plan rest stops, tell how far I was from Los Angeles, etc.

QuoteA driver misjudging the distance of a kilometer could- it's unlikely, but it could actually pose a safety threat. A driver that doesn't know how far a kilometer is or mistakes it for a mile could very well make distance-based decisions that are dangerous. Just because you or I wouldn't doesn't mean that it couldn't happen.

A lot of Swiss-cheese holes would have to line up in order for it to happen, though.

The suggestion that a driver unfamiliar with kilometers could misinterpret distance and initiate a maneuver without a full appreciation of the danger involved assumes that most drivers can take information given in miles and relate it to maneuvers they wish to carry out.  I don't think that is actually true.  I think most drivers rely on a visual assessment of relative speeds, which is invariably imprecise, and make their decision based partly on that and partly on their assessment of where they are in the advance guide signing sequence for an exit.

QuoteYou have to remember that roadgeeks are not standard travelers.

I have not forgotten that.  I traveled on I-19 before I was a roadgeek, so I have an ordinary driver's perspective on metric signing on I-19.

QuoteThe experience you or I or pretty much anybody reading this forum have driving down the road  is not a very good representation of what the actual traveler notices or cares about. Our experiences are nearly irrelevant, because we're trained to be hyper-astute to anomaly. Even if you're optimistic- say 75% of travelers notice and are aware of things like exit numbers and their function (I'd say that 75% is optimistic for being aware of how exit numbers are supposed to work), that leaves a full 25% of travelers who don't. That's a very significant number.

There is not much in this argument since drivers vary in their level of familiarity with the roads they are using.  A local driver, for example, doesn't really need to have information about exit numbers because he or she is relying on underlying knowledge of the road system.  A stranger driver, on the other hand, will be aware of exit numbering (especially if trying to follow directions which presume some familiarity with them), partly because he or she will have had to invest in some study of maps in order to come to grips with an alien road network.  The pie piece to worry about, which I think is actually very small, is the stranger drivers who don't understand the basic affordances of the freeway guide signing system.

Think about the people in Wichita who say "I-35" when they mean Canal Route (I-135), or in Tucson who say "I-10" when they mean I-19.  Do you think these people get lost every day on the way to work?  No.  They know their way around, so they have the freedom to be sloppy.  Outsiders can lecture them about their road systems because they have actually had to put some effort into studying them.

QuoteBut I'd bet nearly 100% of travelers notice when things are posted in metric, and some of those have little idea how metric units play out over space.  I'd say that once again, the roadgeek brain seems to be a lot more spatially aware than the average bear- so your ability to adapt to a kilometer instead of a mile is probably a lot better than the general populace.

Not really.  I know that 1 mile = 1.6093 km, but this doesn't really help me when I am driving, because I don't have any way of accepting, let alone reacting to, precise speed and position inputs.  When I approach an exit, I make a decision as to whether to stay on or turn off, and if the latter, whether to overtake or not, based on whether I can see advance guide signs for that exit.  Placement of advance guide signs is pretty standard on I-19 notwithstanding the use of metric units.  If a sign tells me "Arivaca Rd 500 m," I interpret that as "get ready to exit for Arivaca Road here," the same way I would if I saw a sign saying "Arivaca Rd 1/4 mile."

For drivers of whatever level of familiarity with traffic signing standards, consistent progression of advance guide and exit direction signs is more important than the units actually expressed on the advance guide signs.

Let me try to illustrate with an example taken from a different context.  Per UVC, it is legally required to signal 100 feet in advance of a turn or lane change on a conventional road, and 300 feet in advance on a high-speed road.  Do you think the police pull people over for not turning on their blinkers until 99 feet before the turn on conventional roads, or 299 feet on high-speed roads?  No.  In practice the usual criterion for turn-signal enforcement is whether the signal is visible at all.

P.S.  I actually find metric signing a bit harder to deal with in Canada and Mexico than on I-19, because I-19 still has a speed limit in customary units.  I like to comply with speed limits when I am on long-distance roadtrips (I don't want to be constantly looking out for American bears, let alone foreign ones), and setting the cruise control for speed limits in km/h means looking for figures on a hard-to-read second dial.

Switch all BGS back to customary units. I prefer metric, but the USA uses customary units.

Borders mean things.  Things change at borders.  In the USA "standard" units are used, signs are in English, and certain driving rules apply.  When you get to a border, you are in another jurisdiction, and other rules apply.  You know this, because crossing a border involves an activity that is certainly more complex than merging from one interstate to another. 

This is safe.  Everyone, even the most casual driver, know exactly when the measurement system, language, and other rules of the road will change.  At the border.  Not when you get off I-10 (or worse yet, a side road) and onto I-19.  Safe, consistant, and simple.  And, as to "Mexicans not knowing what is going on", this is silly.  First, of course, it is naive and silly to think that I-19 is the only road driven by Mexicans, or any other people that use metric system.  Millions of people drive in the USA and adjust to "standard" signage every day.  But more importantly, millions of people (including myself) have certainly driven safely in both Canada and Mexico w/o any language or measurement issues.  Doping out the little bit of any of the three major North American languages used in road signage is not even hard, the words are near cognates and easily figured out from the context, sign shape, and such. 

The myth that I-19 is metric because of Mexico was already debunked.

Keep I-19 metric.  I hope metric spreads to other highways.  The world has made its choice, based on merit.  The U.S. will have to convert eventually.  The longer we wait, the more painful it will be.

A special dumbbell award to California, for not adopting exit numbers based on km back around 2000 when they started signing the exit numbers.

Would have been interesting to see Exit 1274 at Hilt on I-5...

Or perhaps Exit 1416 on I-10 in Texas!

I say leave I-19 as is, because of its uniqueness. Also, when you first pass Exit 99 and think that you are 99 miles from Mexico, and then make it to the border thinking: "Wow, that was the quickest 99 miles I've ever driven", not realizing it was closer than you originally thought, it can make for a hilarious road trip story.

Only way metric will ever work in the US is to make everything metric & just force us to get used to it.  Just like the dollar coins, if you don't get rid of the paper dollars they will fail.

Quote from: kkt on January 30, 2012, 02:10:53 AM
Keep I-19 metric.  I hope metric spreads to other highways.  The world has made its choice, based on merit.  The U.S. will have to convert eventually.  The longer we wait, the more painful it will be.

A special dumbbell award to California, for not adopting exit numbers based on km back around 2000 when they started signing the exit numbers.

Why?  A dual system works just fine.  We don't need to switch our roads over to a system people don't want to use.  Hell, the Canucks still use Imperial for a lot of things even with the switch over in the 70s.

Quote from: Brandon on January 30, 2012, 07:48:09 PM

Why?  A dual system works just fine.  We don't need to switch our roads over to a system people don't want to use.  Hell, the Canucks still use Imperial for a lot of things even with the switch over in the 70s.

And the British - despite going metric for just about everything - still use miles like we do.

When I-19 and Delaware 1 are the ONLY examples - nationwide - of metric exit numbers, that really doesn't present a case that the switchover for distance units is going to happen any time soon in the US.

Quote from: kkt on January 30, 2012, 02:10:53 AM
A special dumbbell award to California, for not adopting exit numbers based on km back around 2000 when they started signing the exit numbers.

Wait... what?!?!?  Why should California do that and use a system that NO ONE (with the exception of I-19 and DE-1) else in the US uses.  There was absolutely NO push in the US to convert to metric in 2000 so why does California get the "dumbbell award" for using a system that the rest of the country uses, namely mileage based exit numbering.  That comment just doesn't make any sense to me.

Besides, IIRC, all metric signs were removed from the current MUTCD and in California's case, all of their standard plans, which were in metric, were converted back into Imperial units a few years ago.

Quote from: myosh_tino on January 31, 2012, 02:05:27 AMin California's case, all of their standard plans, which were in metric, were converted back into Imperial units a few years ago.

does this mean there are signs out there which are exact multiples of centimeters in key dimensions?  I have never been able to spot such a thing.  sometimes in Canada I can see what is a metric sign that is attached to an inch-based signpost because the bolts are just slightly askew, but I've never seen such a thing in the US.

Quote from: agentsteel53 on January 31, 2012, 11:45:08 AM

Quote from: myosh_tino on January 31, 2012, 02:05:27 AMin California's case, all of their standard plans, which were in metric, were converted back into Imperial units a few years ago.

does this mean there are signs out there which are exact multiples of centimeters in key dimensions?  I have never been able to spot such a thing.  sometimes in Canada I can see what is a metric sign that is attached to an inch-based signpost because the bolts are just slightly askew, but I've never seen such a thing in the US.

I think I may have misspoke.  I believe Caltrans' standard plans were in dual units (Imperial and metric) with the metric version being the "preferred" version.

Quote from: agentsteel53 on January 31, 2012, 11:45:08 AMdoes this mean there are signs out there which are exact multiples of centimeters in key dimensions?  I have never been able to spot such a thing.  sometimes in Canada I can see what is a metric sign that is attached to an inch-based signpost because the bolts are just slightly askew, but I've never seen such a thing in the US.

I don't think so.  Back when Caltrans was still dimensioning signing plans in metric units, the measurements were typically odd multiples of 5 mm, rather than 1 cm:  so, for example, the word "MILE" in a distance expression (normally 12" tall in Caltrans sign specs approved as part of the Great Redrawing of 1971) was 305 mm rather than 300 mm.  Caltrans was one of the earliest state DOTs to attempt conversion to metric units for construction, and stuck with it after many other state DOTs abandoned their metrication initiatives, but with all the old English-units hardware it has and its emphasis upon reusing and recycling, I don't think Caltrans ever felt free to hard-convert instead of soft-convert.  (In the context of metrication, "soft conversion" implies near-exact conversion of English units into metric units, while "hard conversion" entails the added step of rounding the soft-converted values up or down to "nice" numbers in metric.)

It cannot be overstated that there is a huge divide between converting to metric for distance expressions on signs and converting to metric on construction plans sets.  The former is essentially window-dressing; it is possible to have metric unit expressions on signs made from construction plans dimensioned entirely in English units, and indeed that is how Arizona DOT has always done I-19.  The latter was popular among bridge designers because it allowed bridge strength calculations to be dimensionally correct and thus easy to check (they are not when done in customary units), but almost everyone else hated it.

Quote from: myosh_tino on January 31, 2012, 02:05:27 AM

Quote from: kkt on January 30, 2012, 02:10:53 AM
A special dumbbell award to California, for not adopting exit numbers based on km back around 2000 when they started signing the exit numbers.

Wait... what?!?!?  Why should California do that and use a system that NO ONE (with the exception of I-19 and DE-1) else in the US uses.  There was absolutely NO push in the US to convert to metric in 2000 so why does California get the "dumbbell award" for using a system that the rest of the country uses, namely mileage based exit numbering.

Because the entire rest of the world uses metric, and eventually the US will have to as well.  Continuing to use a system that no one else uses makes our products less competitive in other countries, makes products more expensive for us here, and makes computation unnecessarily hard.  All this was obvious by the 1970s, but not pushed hard enough at the time, so California and other states had the expense of starting to convert a little bit, then converting back to US customary units, and in the future they'll have the expense again of converting back to metric.  Exit numbers based on km would have been a great opportunity to save that future expense without having to change miles to km in other signs at the same time.  Now the expense and confusion of changing exit numbers will be another reason to continue putting off the inevitable.

In the UK, we're far more on the cusp of metric, yet I doubt we'll ever change over unless finally forced to go all the way by an outside, authoritarian force.

We have Continental European beer companies making pint (well 568ml) cans/bottles of beer for our market as it's more popular than 500ml cans/330ml bottles - selling them at no more expense (and when it comes to milk, containers in 500ml multiples, rather than 568ml multiples (it's illegal to sell anything but draft beer in pint multiples), tends to be more expensive).

I don't see America going metric unless something drastic has gone wrong. Metric doesn't win in a free market as people don't like it, nor want it, and the US market is big enough to make things in other units without affecting economies of scale - the use of customary measures are not driving prices up or hurting trade, or people would actually want it - other than the standardisation authoritarians.

Then again, while the UK and US going metric would be worrying for freedom and sovereignty, I think there would be far bigger (though probably less visible) infringements of our liberties taking place than our units being banned if it were to happen.

Since most of the US is surveyed in mile squares, changing would have a detrimental effect on distance estimation.

ugh...my years of chemistry and physics have taught me to love metric, but my whole life i have used standard, and love it dearly...supporting either one is like being a packer fan and cheering for the bears, because i know if they win it will benefit us....still makes me cringe...so i would compromise, and say put both on...standard, because it is after all 'the standard' for highways in the us, and metric to help our neighbors, and because we seem to be slowly switching over.

Just make it happen.  Now, while it seems we have to replace all the signs anyways for reflectivity requirements, Clearview, putting exit numbers on signs...

New signs should be metric.  Or...start at the borders and work our way in.  That way the border areas that are already familiar with metric measurements in Canada and Mexico will have an easy adjustment...then further and further in...  Start with the Interstates, then the non-Interstate NHS routes (starting with primary routes, than the 3dis.)  The states can set their own timetables for state, county and city routes.  Set a deadline of 2020 for all signs on the NHS (Interstate and non-interstate) to be completed.

Quote from: sp_redelectric on May 07, 2012, 08:54:23 PM
Just make it happen.  Now, while it seems we have to replace all the signs anyways for reflectivity requirements, Clearview, putting exit numbers on signs...

New signs should be metric.  Or...start at the borders and work our way in.  That way the border areas that are already familiar with metric measurements in Canada and Mexico will have an easy adjustment...then further and further in...  Start with the Interstates, then the non-Interstate NHS routes (starting with primary routes, than the 3dis.)  The states can set their own timetables for state, county and city routes.  Set a deadline of 2020 for all signs on the NHS (Interstate and non-interstate) to be completed.

Why?  What's the advantage of switching over the roads except to be like everyone else?  There is no solid reason for it.  A mixed system works just fine.  Give me my gallon of milk, two liter of pop, and take me a mile down the road for a 500mg prescription.  Our system right now fits the grid on the ground.

Reopened the poll in case there's further interest.

Quote from: Brandon on May 08, 2012, 11:20:12 PMGive me my gallon of milk, two liter of pop,

ahem, metric is "soda".  pop comes in quarts.

Quote from: agentsteel53 on May 09, 2012, 11:52:43 AM

Quote from: Brandon on May 08, 2012, 11:20:12 PMGive me my gallon of milk, two liter of pop,

ahem, metric is "soda".  pop comes in quarts.

Yet baking soda usually comes by the pound, and pop tarts are sold in boxes.

Quote from: kphoger on May 09, 2012, 04:45:10 PM

Yet baking soda usually comes by the pound, and pop tarts are sold in boxes.

pop tarts are usually wholesaled by the furlong

Quote from: agentsteel53 on May 09, 2012, 04:50:38 PM
pop tarts are usually wholesaled by the furlong

Your face is a furlong.

Quote from: kphoger on May 09, 2012, 05:05:32 PM

Your face is a furlong.

a horse walks into a bar...

I think Interstate 19 should be signed using milage. In the USA we don't use metric, we use the standard system.

However, nowadays, most of the world is using metric as the standard unit of measurement.

Quote from: sr641 on May 09, 2012, 08:05:50 PM
I think Interstate 19 should be signed using milage. In the USA we don't use metric, we use the standard system.

We do use metric.  Just not on road signs.
When was the last time you bought a 4.23-pint of Pepsi?  Or taken 17.6 milliounces of Tylenol?
Just saying...

Is it legal to sell 2 litre bottles of Pepsi? In the UK, we can buy containers of (usually milk and beer/cider) that have a (UK) pint in them, but they are officially 568ml, rather than a pint as you can't sell anything but draft beer/cider in pints.

The bottle of milk in my fridge is labelled with 2.272 Litres (4 pints), though they've either stopped putting the big number 4 on the label, or that was ASDA not TESCOs. They can give the pint equivalent, but it must be afterwards and as-or-less prominent. They could get away with the number as it was part of the branding and made no reference to pints.

You also get odd sizes for canned food, until you calculate that it's a whole number of ounces (though even then a bit of a strange number). Market traders often give the price per 454g/1lb, as they want to use pounds (and people want to buy in pounds), but by law have to sell in metric.

Quote from: english si on May 10, 2012, 11:46:10 AM
Is it legal to sell 2 litre bottles of Pepsi? In the UK, we can buy containers of (usually milk and beer/cider) that have a (UK) pint in them, but they are officially 568ml, rather than a pint as you can't sell anything but draft beer/cider in pints.

That's the standard for parties.  We have cans and small bottles measured in ounces, then 1-liter bottles and 2-liter bottles.  And nobody bats an eye.

Yeah, in the US, I am pretty sure you can market it however you wish, as long as you give a conversion at the bottom of the label. So soda is sold in 12-oz cans and 20-oz bottles, and then the larger sizes are 1 liter and 2 liter (I have seen 1.5 liter and 3 liter as well). But milk is sold by the gallon and turkey by the pound. Drug dosages tend to be quoted by the milligram. Pencil lead and pen thickness is measured in millimeters. It's all sort of stupid.