Old MUTCD in PDF format?

[Dr Frankenstein]

And yet I'm probably the lone Clearview fan here. Go figure.

We're two.

[Quillz]

And yet I'm probably the lone Clearview fan here. Go figure.

We're two.

The Clearview Cult has a new member!

[mightyace]

^^^

Just, watch out for the Kool-Aid! 

[Roadsign199qc]

We're three to love Clearview.

[Quillz]

That's good, but we shouldn't get off-topic. There is a topic here about Clearview, we should probably post there, since this topic is about the MUTCD, or the lack of one.

[J N Winkler]

who is Forbes?

Theodore Watson Forbes, as in co-author of the Forbes and Moskowitz paper of 1950 which established the mixed-case option (later made a standard) for freeway guide signing, a 1957 paper on VMS on the Mackinac Bridge, etc.

His main contribution, and the reason I call myself a "back-to-Forbes fundamentalist," was a series of papers between 1938 and 1942 establishing criteria for the design and placement of guide signs in order to allow them to be read in full, twice, in the time they were visible to drivers.  Forbes started with the observation that a sign would be visible to drivers only within a certain range of observation angles, and at a given speed that translated to a certain length of time available to read the sign legend.  That, combined with the number of words on the sign and the intrinsic legibility of the traffic sign alphabet used (expressed as feet of reading distance per inch of letter height, with Series D having a reference legibility of 50 feet per inch of letter height), translated into a minimum letter height in order to allow the sign to be read twice in its entirety in the time it was visible to the driver.

the D digits fit just fine into the '61 spec.

They fit, yes.  "Just fine," no.  Later research into traffic sign legibility (performed by the Road Research Laboratory in the UK) showed that a certain space cushion between letters and between letters and surrounding elements like borders is necessary for optimum legibility.  On this particular sign there is too little space to either side of "66" and there is also bad visual balance between the white space on top and the white space on the sides.

In general I disagree with others' passion for older shield designs for functional reasons.  There are generally good reasons the old designs were abandoned.  In the case of the old-style US shield with crossbar, "U S," and state name, the digits were too small.  In fact the classic US shield as shown in the 1927 AASHO manual is a pre-Forbes design.  In the case of the 1957 Interstate shield, the price of a message space capable of accommodating two- and three-digit routes on the same sign blank was too-small digits.

Others on this board have often criticized three-digit shields drawn to the usual 125% width ratio because they are seen as too bloated or visually unbalanced.  I agree with this criticism but not the reasons usually quoted for it.  In my experience, the width ratio is too low for common shield designs like the US route shield to accommodate all possible three-digit designations at a consistent choice of alphabet series, digit height, and intercharacter spacing.  Some state DOTs, like MnDOT, deal with this problem by establishing Series D as an inflexible standard and forcing all digit heights down to that required to create an adequately padded message space for three "fat" digits on the standard three-digit US route marker.  Others use smaller heights or more condensed alphabet series for three-digit routes, which is not justifiable because three-digit designations need as much legibility as two-digit designations.  Other states, like South Carolina, have bespoke US route shield designs which allow the use of a consistent digit height for all US route designations on a large guide sign, regardless of digit count and breadth.  South Carolina does this by allowing varying heights for US route shields and a width ratio which can vary up to 150%.  (South Carolina also uses Series E rather than Series D, which is another legibility improvement since Series E has higher intrnsic legibility than Series D.)  Back in the days of outline shields, Caltrans had slide-out design variations for the US route shield which were designed to accommodate different combinations of digit count and breadth while maintaining even padding on all four sides of the digit block.

The 1961 US route shield is the federal authorities' gift to Russ Meyer fans, but it is functionally inferior to the current design because the message space is too narrow.  The 1971 shield has class and a message space of ample width.

[agentsteel53]

I'm not going to doubt that the '70 is easier to read because I'm too lazy to perform my own functionality tests.  But class?  I think not.  The shield shape looks like it was inflated with an air pump, as opposed to with someone paying careful attention to how to increase the area of the white surface while maintaining somewhat sensible proportions. 

for a decent compromise, I'd look at the 1957 specification "California style" shield, which looks a whole lot better than the '70, while also allowing for much more room for D digits.  (The "US" would have to be taken out of the shield of course.)

[Quillz]

At the end of the day, though, as long as any given individual motorist can read the numbers on a shield, does it really matter what it looks like? I don't find California's cutout US Route shields any less legible than the '71 spec that almost all other states use. And that's because, I think, motorists don't just read numbers but recognize shapes. The Interstate shield and the cutout US Route shield have very distinctive shapes that aren't used for anything else (at least they aren't supposed to be.) A lot of motorists navigate freeways not always by number but by class: they know that an Interstate highway will get them SOMEWHERE important, even if they don't read the number and know exactly where.

Numeral legibility is important, very important, but it's not the only factor.

[mightyace]

A lot of motorists navigate freeways not always by number but by class: they know that an Interstate highway will get them SOMEWHERE important, even if they don't read the number and know exactly where.

I can't say how many there are of this type but I don't know anyone who navigates like this.  And, since US, state and county routes can be anything a narrow country road to an interstate-grade freeway, the only "class" that means anything is the interstate shield.

Everyone I know navigates by number and, if anything, they do not distinguish between US and state routes and, sometimes, not even interstates.

I serve up as evidence the large number of advertising signs and maps that use the wrong shield type.

[Quillz]

Could be a regional thing, maybe. But I know that I've been with motorists in the past whose main concern was "getting on an Interstate," even when they had no idea what number it would be or where it would lead.

[agentsteel53]

Could be a regional thing, maybe. But I know that I've been with motorists in the past whose main concern was "getting on an Interstate," even when they had no idea what number it would be or where it would lead.

I'm a pretty experienced driver, and I do that!  Reason being, I know once I'm on a red-white-and-blue road, I won't be stuck at a traffic light*.  It takes fewer years off my life to be on the road going in the wrong direction, at quite an impressive speed, than waiting for the fucking traffic light to turn because everyone and their idiot semi-cousin needs to shop at Walmart at this very given moment.

(*which is why I once lost bowel control when I got on I-180 in Cheyenne hoping to make a quick dash out of sprawl hell.)

[D-Dey65]

There is no 1957 MUTCD.  What you are probably looking for is the Interstate signing and marking manual, which came out (IIRC) in 1957 or 1958.  Old MUTCDs in general (but not the Interstate signing and marking manual) are available on Richard Moeur's site:

http://www.trafficsign.us/oldmutcd.html

I just spotted that tonight. I've been to Richard Moeur's site in the past, but if I was ever on the old MUTCD's page, I forgot about it. I read about it after reading another site on road signs, and was quite surprised to find that according to the 1961 MUTCD, the Detour signs (M5-7) were supposed to have white arrows (I always thought they were yellow). Also I saw red and white "Do Not Enter" circles before 1971.