Interstate Shields in CA

[WestSide Highway]

Why does CA have the 3 sizes for interstate shields? 21x18, 24x24, and 36x36. Did they try experimenting with some to see what kind they like? I know the standard size is 24x24.

[The Ghostbuster]

Since I've never been to California, I don't have a clue. By the way, does anyone know if any other state has multiple sized Interstate Shields?

[myosh_tino]

Why does CA have the 3 sizes for interstate shields? 21x18, 24x24, and 36x36. Did they try experimenting with some to see what kind they like? I know the standard size is 24x24.

* 36 x 36 shields are generally found on freeways as reassurance markers after an on-ramp.
* 24 x 24 shields are generally found on non-freeway roadways as way-finding (TO/I-5/-->) or on freeway entrance assemblies.

[sparker]

Out of curiosity, does anyone know the actual dimensions of the vertically extended Interstate shields that Caltrans was deploying in the late '90's?  Many of the I-5 iterations were used on the Santa Ana Freeway in L.A. and Orange counties; their use seemed to cross district lines.  These are the ones that came to a sharp point at the base and had a relatively narrow cross-section (I referred to them as the "bat-signal" signs!).

[myosh_tino]

Out of curiosity, does anyone know the actual dimensions of the vertically extended Interstate shields that Caltrans was deploying in the late '90's?  Many of the I-5 iterations were used on the Santa Ana Freeway in L.A. and Orange counties; their use seemed to cross district lines.  These are the ones that came to a sharp point at the base and had a relatively narrow cross-section (I referred to them as the "bat-signal" signs!).

I believe those are 36 x 36 shields as they're only found on freeways as reassurance markers.  I am of the belief that these angular shields are the 42 x 36 3-digit interstate shield squished down to 36 x 36...

[sparker]

I believe those are 36 x 36 shields as they're only found on freeways as reassurance markers.  I am of the belief that these angular shields are the 42 x 36 3-digit interstate shield squished down to 36 x 36...

Yeah, the one on the right is what I was talking about.  Seems like the perception that it looks taller than wide is just an optical illusion; putting a set of calipers to your visual confirms that W and H are the same.  Thanks for the insight -- and the illustration!

[myosh_tino]

I believe those are 36 x 36 shields as they're only found on freeways as reassurance markers.  I am of the belief that these angular shields are the 42 x 36 3-digit interstate shield squished down to 36 x 36...

Yeah, the one on the right is what I was talking about.  Seems like the perception that it looks taller than wide is just an optical illusion; putting a set of calipers to your visual confirms that W and H are the same.  Thanks for the insight -- and the illustration!

We actually had a discussion about the angular and bubble interstate shields back in 2010.  Here's a link to my post in that discussion where I originally posted the above drawing... https://www.aaroads.com/forum/index.php?topic=2253.msg51629#msg51629

[Exit58]

I haven't seen any new angular shields posted. Have the sign shops stopped printing them? The 10 from Ontario to Rialto is full of angular reassurance shields (eastbound anyway) and I don't really mind them. I'm not partial to one or the other. There are some posted in the Arcadia area too for I-210 (yes they printed a 3di on 2di shield).

The bubble shields though are hideous.

[sparker]

The bubble shields though are hideous.

Totally agree -- lots of them posted on I-880 in the Hayward-San Leandro area, mostly on lighting fixtures above the sound walls.  Whoever devised that shield design should get their visual prescription checked -- unless the concept was due to simple laziness!

[TheStranger]

Whoever devised that shield design should get their visual prescription checked -- unless the concept was due to simple laziness!

On this forum I recall someone theorized that the bubble shield is the result of taking the standard 2di shield and attempting to stretch out the dimensions in a graphics editor of some sort!

Needless to say, it isn't an elegant solution at all (especially when a separate 3di shield of different dimensions already existed).

[myosh_tino]

On this forum I recall someone theorized that the bubble shield is the result of taking the standard 2di shield and attempting to stretch out the dimensions in a graphics editor of some sort!

Needless to say, it isn't an elegant solution at all (especially when a separate 3di shield of different dimensions already existed).

Yep, that would be me!

The bubble shields though are hideous.

Totally agree -- lots of them posted on I-880 in the Hayward-San Leandro area, mostly on lighting fixtures above the sound walls.  Whoever devised that shield design should get their visual prescription checked -- unless the concept was due to simple laziness!

Huh?  I've travel up and down I-880 all the time and have *never* seen a bubble shield posted anywhere except on BGSes on westbound I-80 approaching the MacArthur Maze.  The only place I've seen bubble shields used as reassurance markers (usually found after on-ramps affixed to light poles) is on I-680 between Mission Blvd/CA-238 and Auto Mall Pkwy.

[sparker]

Huh?  I've travel up and down I-880 all the time and have *never* seen a bubble shield posted anywhere except on BGSes on westbound I-80 approaching the MacArthur Maze.  The only place I've seen bubble shields used as reassurance markers (usually found after on-ramps affixed to light poles) is on I-680 between Mission Blvd/CA-238 and Auto Mall Pkwy.

The ones I've seen are scattered around the 880/92 interchange, never seen them south of Tennyson nor north of the I-238 interchange.  Hard to spot if you're not looking for them; they're tucked away well above most lines of sight.  I haven't been SB on I-880 for a couple of months (usually taking surface streets during peak hours), but I do remember at least 2 NB as of early July.  I started seeing them around 2008 when I was in the area sporadically; they were deployed in both directions then.  I've never seen one outside of the "atop the sound wall" placement.  I'll be going NB again on business a couple of weeks from now; I'll recheck things and post the results.
If indeed they've been replaced by conventional shields, then good riddance!

[Quillz]

I believe those are 36 x 36 shields as they're only found on freeways as reassurance markers.  I am of the belief that these angular shields are the 42 x 36 3-digit interstate shield squished down to 36 x 36...

Yeah, the one on the right is what I was talking about.  Seems like the perception that it looks taller than wide is just an optical illusion; putting a set of calipers to your visual confirms that W and H are the same.  Thanks for the insight -- and the illustration!

It's just an optical illusion, they are actually square in terms of dimensions. On the other hand, I've always thought the miner spades look wider than they are tall, but this isn't the case with the standard shield: it's one inch taller than wide (24'' by 25''). As for those "angular shields," they still pop up from time to time. There are a lot on the 5 between the 138 and 99, and the 80 has several east of Sacramento.

[Quillz]

As to why California made (and still makes) the 21'' by 18'' shield, I dunno. If you upscale it, you'll get a shield that is roughly 28'' by 24'', which would slot it in nicely between the 24'' by 24'' and 30'' by 24'' shields that are fairly standard. Perhaps at some point, 3di were intended to be slightly narrower but the numbers didn't fit, hence the 30'' by 24'' dimensions, but no one told Caltrans.

What's also interesting is that California also "officially" uses 30'' by 25'' shields for 3di, at least on guide signs. That little bit of extra height allows for the three-digit routes to fit quite comfortably inside the shield, I find. Even with the thicker white margins that Caltrans uses (roughly .75'' vs. the federal standard of .5''.)

[andy3175]

I have seen the "angular shields" occasionally used in Caltrans District 7 (LA/Ventura Counties) for mainline reassurance/confirming three digit interstate installations, such as this one along I-605:

https://www.google.com/maps/@33.9056712,-118.1050501,3a,75y,354.66h,101.01t/data=!3m6!1e1!3m4!1s-BgjzmzJJU4oPPnNmqkwdg!2e0!7i13312!8i6656

For comparison, here's a more "normal/typical" I-605 shield just a few miles north of there:

https://www.google.com/maps/@33.9275314,-118.1032297,3a,75y,13.04h,90.77t/data=!3m6!1e1!3m4!1sQ2am4qMGI_O6RIwm1EbLug!2e0!7i13312!8i6656

My original theory was that some Caltrans districts may have wanted one shield shape for any possible one, two, or three digit combinations, but I've not really seen many three digit Interstates using the "angular shield." This 605 example is not really widespread near as I can tell. Instead, I've seen bubble shields, "flat" shields, traditional/older specification shields (numeral size often varies), and angular shields (most of the neutered 36"x36" mainline reassurance shields I've seen in California are angular, but the neutered freeway entrance and trailblazer shields are usually the more traditional shape since angular shields don't usually appear at those locations with generally 24"x24" smaller shapes), all used on a generally inconsistent basis across California.

For what it's worth, Joel Windmiller used to describe the "angular shields" as "renaissance shields" back when they first appeared in the late 1990s.

[myosh_tino]

I have seen the "angular shields" occasionally used in Caltrans District 7 (LA/Ventura Counties) for mainline reassurance/confirming three digit interstate installations, such as this one along I-605:

https://www.google.com/maps/@33.9056712,-118.1050501,3a,75y,354.66h,101.01t/data=!3m6!1e1!3m4!1s-BgjzmzJJU4oPPnNmqkwdg!2e0!7i13312!8i6656

I know of only one instance of a 36 x 36 angular 3-digit Interstate shield up here in northern California and that's on I-205 westbound after the Grant Line Road interchange... https://goo.gl/maps/yTjbW8fQ55M2

[Bobby5280]

I've seen a few odd shields like that here in Oklahoma. For instance there's a couple or so odd I-35 shields near the end of the Turner Turnpike and I-44/I-35 interchange:
Google Maps: https://goo.gl/EnPn6u

[myosh_tino]

I've seen a few odd shields like that here in Oklahoma. For instance there's a couple or so odd I-35 shields near the end of the Turner Turnpike and I-44/I-35 interchange:
Google Maps: https://goo.gl/EnPn6u

I'm surprised they used state-named shields on guide signs.  That's not very common although I do seem to recall this being common practice in Oklahoma.

It's also a little surprising to see that "angluar" shield on the same gantry as two normal looking shields.

[Bickendan]

I haven't seen any new angular shields posted. Have the sign shops stopped printing them? The 10 from Ontario to Rialto is full of angular reassurance shields (eastbound anyway) and I don't really mind them. I'm not partial to one or the other. There are some posted in the Arcadia area too for I-210 (yes they printed a 3di on 2di shield).

The bubble shields though are hideous.

I'm one of the few that likes the bubble shields. While I agree they shouldn't be used (because they're not spec), I find them much more visually pleasing than the CalTrans verticals.

[Exit58]

I'm one of the few that likes the bubble shields. While I agree they shouldn't be used (because they're not spec), I find them much more visually pleasing than the CalTrans verticals.

To each their own. Here is the only bubble shield I have seen personally in the southland, and it's for I-210. 99% certain it's not Caltrans issued though. No markings, it's a directional at a mall 2-3 miles south of the freeway, and it's actually SR-210 through here (still, grumble).