FM/RM Routes on BGS

[OCGuy81]

I was always curious why Farm to Market routes use a rectangle on big green signs, but when you see the reassurance signs, they're Texas shaped.

Is this the only state where the BGS cutout doesn't match the reassurance signs?

[kphoger]

The shape?  Maybe.

But other states have less noticeable differences.  For example, Nebraska state route shields on guide signs don't have the state name.  Michigan's don't have the M on them.  Etc.

[Road Hog]

I'm sure readability is the reason.

[Scott5114]

Yeah, the FM/RM shield is pretty iconic and "cool" as shields go, but it actually sort of sucks at being a shield. By the spec, a four-digit, 24-inch FM shield has 4" numbers, just a hair over 15% of the height of the shield. (The MUTCD recommends digits be 50% the height of the shield.) Given that most 4-digit FM/RMs are minor roads that the vast majority of travelers will have no reason to use, this is mostly fine. When you're signing a freeway, though, higher standards are called for.

[kphoger]

Yeah, the FM/RM shield is pretty iconic and "cool" as shields go, but it actually sort of sucks at being a shield. By the spec, a four-digit, 24-inch FM shield has 4" numbers, just a hair over 15% of the height of the shield. (The MUTCD recommends digits be 50% the height of the shield.)

This is why I laugh and cringe whenever someone suggests Texas should switch their primary and secondary route shields.  The state outline would totally suck for primary routes.

Given that most 4-digit FM/RMs are minor roads that the vast majority of travelers will have no reason to use, this is mostly fine. When you're signing a freeway, though, higher standards are called for.

It's not even all that great for FM routes.  Given that many such highways have a speed limit between 65 and 75 mph, my typical thought process goes something like this:

Junction with an FM route coming up.  This may or may not be my turn.
OK, it appears to be four digits.  Still, this may or may not be my turn.
Yep, that first digit is a 2.  Time to slow down.
Nope, never mind.  That's 2690.  I'm looking for 2730.

Really, it's hardly any better than regular street blades.

[Bobby5280]

While the Texas FM/RM sign post shield is culturally iconic, it might be the least legible highway route marker in use in the United States. Distance legibility is just bad.

I could imagine a response like, "if you can't read the sign why not just use your GPS?" My reply would be, "why bother installing those signs in the first place?"

[hbelkins]

The shape?  Maybe.

But other states have less noticeable differences.  For example, Nebraska state route shields on guide signs don't have the state name.  Michigan's don't have the M on them.  Etc.

Also, standalone route markers for regular state routes have "TEXAS" below the number. It's above the number on BGS installations.