How do engineers make ROAD SIGNS look the same

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Road signs are awesome. They're probably my favorite part of the road. When you drive a little tiny car like mine, you never have any fun. Except for one way: that's carving around the corners. How could that not put a smile on my face, right? Big yellow warning signs like these tell a spirited driver like you and me that we might need to slow down a little bit.

And at night, they can literally save your life. The sign means the same thing here in California as it would on a windy road all the way across the country in, say, the Carolinas. Which is pretty impressive. Here in America, we're independent thinkers, 50 different states. I'm quite impressed.

We didn't end up with 50 different sets of roadside horrible, localized masses. This is a non-conforming road sign that the tree is eating. And that's a good thing because this sign is terrible. We have the National Field Archery Association with an arrow that looks like an arrow.

We have a bunch of fruit. And don't forget "antique row," whatever that is. Had America not made an effort to standardize all our road signs, messages like this would be the rule, not the exception. Out on the road, some signs are just more important than others. I mean, this is a good looking sign.

"Old Town District" is not important for driving, but this sign is very important. This is pretty. Not important. Not very pretty. Very important. Not important, not important.

Not important. Some signs are just in a higher class. Signs that inform, guide and control cars and pedestrians are called traffic control devices.

And they follow five basic rules: The sign has to have a purpose. Drivers need to notice it. Understand it.

Follow it early enough in advance to actually carry it out. The only problem? Sometimes traffic control devices work too well, so we put in too many. A driver exiting the freeway may be so distracted by these 11 fantastic signs here, they may forget to pay attention to the stop sign on the off ramp. And as important as it is, to know that business is to the right— compared with the stop sign? You know what I mean? We need national rules.

Couldn't we just have Congress set federal rules for federal highways? Well, America's roads have more than one owner. Even big interstate highways like this one belong to the states. And how do you get 50 states to all use the same signs? You cut 'em a check. The federal government pays states a lot of money to help fix up and expand existing highways. There are rules to get the money.

You have to bring the signs for that project in compliance with the "Manual on Uniform Traffic Control Devices." This is the bible for road signs. Narrator: "Here's how they put them together at the Highland Park plant.". Just over a century ago, Henry Ford's employees started spitting out millions of Model T's onto city streets. No painted lines and few road signs. Growing chaos.

And Detroit wasn't having any of that. So the city put up a two-foot-by-two-foot stop sign. The first of millions. The state of Mississippi copied them, but they chopped the corners off. And an association of state highway officials near the Mississippi Valley all agreed on some unified sign designs. Such a refreshing difference from the localized mishmash of signs all over the country.

Ones police departments and auto clubs painted by hand. Transportation officials from other states liked what they saw in the Mississippi Valley and in 1935 agreed on some common shapes and colors. A yield sign represent some danger. So it gets three corners. A stop sign represents even more danger, so it gets eight. In between, a warning sign which has four corners.

Their logic: The more you have to cut the sign, the more wasteed material there is. So only the most important signs would get the most cuts. A railroad crossing gets a round sign.

Unlimited corners means unlimited danger. Engineers also gave the stop sign its official color: yellow. The 1935 manual had white signs for regulations and navigation. Yellow was for warnings all kinds of warnings. There were no red signs.

At night, my headlights reflect off of this and show me its glorious redness. But in the 1930s, there was no reflective paint. This sign would look black. Yellow at least had a chance of showing up.

In the 1950s, engineers at 3M invented reflective paint. And while the executive responsible had later dealings that would not shine brightly... Nixon: "People have got to know whether or not their president is a crook.".

The signs themselves certainly would shine brightly. Red became the national standard in the 1954 book. Progress is incremental. As engineers saw what worked and what didn't.

They kept updating the manual. The little pamphlet turned into a booklet— which turned into a book— which turned into a manual— which turned into an 800 page phonebook-sized barbell. Lot of rules in here.

More than we could possibly cover in this video. And a lot of don'ts. But I like to think of this book less as a mean tattletale and more as a cool toolkit. One to help cities and states make their signs simpler and safer. Drivers get only seconds to see and understand a traffic control device. Uniform symbols and uniform colors convey an idea really quickly.

That's why businesses create logos and put them on top of tall poles. And that's why every traffic control device is color coded into nine standard hues. These colors are the most common. Red signs are the most important because they convey immediate danger. If for some reason we had to get rid of all the road signs, stop signs are the very last to go and it shows in the manual.

It earns the distinction: Sign number R1-1, with yield signs coming in a close second with R1-2. Critical infrastructure, we rely on 24 hours a day. Glow in the dark magic is called retro reflectivity, and what makes it a little bit different than reflectivity is that would be a mirror. And you don't want to see your headlights.

Retro reflectivity takes the light from your headlights and carries the sign's color back to you. Today, signs of every color are retro reflective, not just the red ones. Our chemical engineering friends have figured out a way to make brown retro reflective.

Check this out. That's pretty cool! In places where you really need the stop sign to stand out, you can have a beacon at the top. A flashing red light. You can even have two wig-wagging back and forth like this. But two blinking horizontally look like a railroad crossing, so they should blink together. Or the manual says you can add a two inch reflective red strip and stick it on the pole here.

But it has to go all the way down to the ground. Many other countries use a different roadside standard. Despite this stop, signs look pretty much the same everywhere except Japan. Stop sign: (saying "STOP" in Japanese, probably) And even when you can't read the sign, it's universally octagon shape still carries the message. Two more signs that warrant the coveted color of red: DO NOT ENTER and WRONG WAY signs.

Which makes sense because nobody wants a car entering the freeway going the wrong way. Some states are even playing with technology that could detect if a car is entering an off-ramp and could make the sign light up. Up next: black-and-white signs. These are the second most important road sign color. We need to pay attention to white signs.

They are regulatory signs. These traffic control devices explain rules and regulations and the most famous one: speed limit signs. As much as I'd like to think of speed limits as being a suggestion. That guy gets it. He's treating it like a suggestion.

Speed limits must be in multiples of five miles per hour, so none of this. If I'm driving and I choose to ignore a white sign, I could end up with a ticket. Rob: "77 is not speeding. You should have seen how fast I was going on the way up there. I mean, don't worry about it.

I'll just pay the ticket." (click). One literary device is to make a sentence.

Add this— to the end of the sign's name. So you have [speed limit 40] or else you could get a ticket. This works with all regulatory signs. We enforce traffic rules because driving is a form of choreography.

Uniform motion that makes our roads safer. We stay light on our feet when traffic rules are uniform. The goal is not to trick people into getting tickets.

We want to follow the rules, and it becomes a lot easier when the signs mean the same thing everywhere. City to city and state to state. Here's a no parking sign. It's white, so I legally have to follow it. Which legally, if I parked here, I'd have to pay the ticket, right? Except the sign doesn't appear anywhere in the manual.

How do I know this isn't a pirate sign— and people are writing me a pirate ticket? Because I don't want to get scammed. When a driver identifies a sign quickly, they're more likely to follow that rule. Look at this cute little art project here. You get the picture of the truck saying "no trucks over three tons." The only problem is the person driving the three ton truck down the street at 50 miles an hour isn't going to readily recognize this non-compliant sign, so they're going to go down the street anyway.

A lose-lose for the city as well. A judge might feel kinda sympathetic and throw out a ticket when they see a non compliant sign. Judge: "A blue STOP sign? And it's not even spelled right! Case dismissed". This is what a speed limit sign looks like in Oregon. Notice it's missing the word "limit." So does that mean a judge in Oregon will get you out of a ticket because the sign is not uniform? Well.

Only these states follow the national MUTCD exactly. These states, like Texas and California, have their own state MUTCD. California literally has sections crossed out and changed, but it's similar enough to keep FHWA happy. And states like Oregon have a state supplement. A few extra rules to bring them into compliance with state law.

And in a tangled mess out of Oregon State Assembly, the word "limit historically" was not supposed to appear on the sign. Oregon's new MUTCD supplement strikes that line, and full speed limit signs in Oregon are becoming more common. Up next, the third most important traffic control device color: yellow. Warning signs are different than white regulatory signs.

That suffix I was using about "getting a ticket" doesn't work anymore. (Sarcastically:) "The bridge is 15 foot three inches or else you're getting a ticket.". Yellow signs indicate natural consequences. Mother Nature is the one writing the tickets. In most of the country, a yellow speed limit sign isn't actually a speed limit. Except for Texas, who install this white regulatory sign which basically compels you to obey the yellow warning signs.

Enforced or not, you and I follow yellow signs because we don't want to crash our car. Warning signs should always be diamond shape. That way, a driver can quickly identify, "Oh, I need to be paying attention to something."

Signs can be two feet tall, typically three feet tall on all roads over 35 miles per hour. And as big as four feet on highways. There's a huge catalog of options for these diamond shaped signs, symbols and text warn about curves in the road. Warn about steep hills, lanes merging, motorized and non-motorized objects to keep an eye out for, including the Amish, and unexpected conditions like narrow bridges or when freeways end. And also in this category, you'll find DEAD END signs, which don't necessarily warn you of imminent danger per se.

But they do help you steer around severe inconvenience, especially if you're driving a big truck and don't want to turn that thing around. But primarily, warning signs prevent crashes. If a manual doesn't already have a sign that conveys the message you want a send, that's OK. It's OK to write your own message to convey the warning. One time I drove this moving truck across Colorado. This sign Colorado DOT made, kept this barely qualified driver safe going down the Rocky Mountains.

But you'll notice this sign is not diamond shaped. When there's too much text to fit inside that diamond, it's OK to put it in a rectangle. This sign is not an example. I don't think that's too much text.

On the other hand... "Tractor-semis over 30 feet kingpin the rear axle not advised." What does that even mean? It has something to do with semi-trucks not making this hairpin freeway entrance. (Off camera:) "Oh, no, it's going to try it like they're doing right here.".

Let's fix this! Now that's a good looking sign. It only uses four words. A sixth grader can understand it.

A truck driver doesn't have to take their eyes off the road very long to read it. One big difference between the U.S. MUTCD warning signs and the Vienna Convention? Ours tend to rely more on the written words and less on symbols. That gives us more flexibility in our messaging, because you can't have an icon for everything. But icons are much faster for a driver to identify. School signs used to also be yellow.

New York state engineers in 1995 found drivers are twice as likely to stop for this color than the conventional yellow. This is now the standard color as of the 2009 manual. Did you know a variable message signed with orange or yellow text is no different than an orange or yellow sign? Up next, my favorite category: guidance.

The big green signs, although it's been a little bit tricky to find a place where I can film and show you one because I have to be on this side of the fence. Because it's not safe to film on a freeway. But it's thanks to interstate highways that we have these signs. Navigation is all about places.

Signs that tell with street, town, or mega-region you're headed for. These signs were traditionally black text on a white background or white text on a black background. If you remember the five rules of a good traffic control device, one of them is being able to have enough time to react to the sign. That's a big deal at 65 miles per hour. So, a 1950s guide on constructing new interstates recommended using upper and lower case letters on a green background.

More natural, easier to read. The letters on those big green signs have to be huge! So I set out to measure one for you to show you how big the letters are. It didn't go well. In the countryside, navigation signs are on the right hand shoulder. But as traffic gets heavier, cars and trucks may block your view. That's where going overhead kicks in.

The destination points directly at the middle of the lane that's headed there. There should never be more than two arrows pointing at one lane. Even with the lane splits in half toward a ramp, you can either angle away the exit arrows or swap everything out for one of the new ARROW PER LANE (APL) guide signs, where the arrows point up. Some engineers hate how tall these APL signs become, but they do solve a real mix up. When a lane has to exit the freeway. We put a little tiny warning sign on the navigation sign.

But how's that "exit only" sign supposed to look? You could put the little yellow "exits" and "only"s next to the exiting arrow and have something like this. Which is fine— or something like this, which is... *fine* (sacastic), I guess. You can encase the exiting arrow and the text in its own big yellow box.

Make the arrow black. So far, so good. Now, to complicate things, two lanes both have to exit the freeway. Well, I suppose you could just put two signs on there.

The manual does have a double arrow sign, which you can use. But what about when the right lane has to exit, but the left lane has a choice? That gets messy! You can put a tag on there like this. Or split the yellow box in half. Or you could do it the "California" way (throwing shade). Or, to pick on another state, use the double yellow arrow again.

Apparently, this is also valid— even when that inside lane has a choice. Well that, or Utah did it wrong. Considering this is a manual that's supposed to limit options, there's an awful lot of ambiguity in this manual on how to describe this. At least an ARROW PER LANE sign forces you to sign it one way. Like 'em or not, at least they're consistent.

When the freeway is really wide, drivers might need a half-a-mile or a mile or more to jockey around and get into the correct lane. So in addition to having the signs be huge, put these huge signs going back in several places. The manual has diagrams to show exactly how to space those signs out. For the sign itself, as a rule of thumb, no more than three lines of text clearly stating the direction, the route and a location. This is called the control city.

It's a place somewhere in the distance that lets drivers who are unfamiliar with the area know the general direction they're heading. You need to be consistent when you pick one. People from out of town are already having a hard enough time paying attention to one town, having two just makes it needlessly complicated. We could easily spend over an hour just talking about freeway signs. Exiting to city streets where speeds are lower, the rules are a little more forgiving. But there are still rules.

Street signs should never have letters any smaller than three inches tall. Even on the tiniest signs. And capital letters should be four inches.

Since this one somehow ended up being all capital letterss, let's measure it. (I should succeed this time.) Between one and five inches; five minus one is four. Four inches tall. The absolute minimum for this any bitty, teeny tiny little street sign.

Text at traffic signals should be much bigger. Where we notice Los Angeles and its famously blue signs. Remember when Terminator II chased Motorcycle Kid through the Sony Pictures parking garage? And then a minute and a half later, smashed into a wash 19 miles away? Well, there's a cameo from our blue movie star.

Are these (signs) breaking the rules? Well, turns out no. In a surprising bit of permissiveness, the MUTCD allows city street signs to be green and blue and brown. And even white. But not blue-green. And look, I get it, cities want to look unique from their neighbors. For their fancy street name sign to follow the rules, it needs to dump all-capital letters for title case.

You can have a highway logo or a city logo, but not both at the same time. And that city logo needs to be on the left hand side and no larger than that first capital letter. It's OK to abbreviate the suffix as long as you do so appropriately, but do not abbreviate the street's name itself.

And make sure the font is nice and big. There, that looks a lot better now, doesn't it? In my humble opinion, a sign like that one is nearly perfect. Just big letters on a plain green background. No block numbers, no logos, no nonsense. Street signs have to be very different when there's no stoplight. There are some people who still find roundabouts stressful.

They get in one, they don't know where to go. A roundabout navigation sign can help them feel more comfortable— going in knowing what their options are. And here's a pretty good one, in Moreno Valley, California. But this roundabout navigation sign has a problem you've probably noticed: What's up with this left-hand turn into the roundabout? And even more noticeably, why is it on regulatory white? Because you know what that means, right? (Sarcastically:) "The cemetery is this way or else you're getting a ticket." Up next: blue traffic control devices.

These are the signs from the movies, "No food, no fuel— thirty-five miles." General Service signs tell you where you can buy fuel, get something to eat, stop for the night. They're more appropriate out in the countryside, where you might not know what's available at an off ramp versus in the city. I wonder if there's a place to buy gas around here? What are the odds? The signs have to be on a blue background with white print, and that print can either be text or symbols, but you're not supposed to use both at the same time. Brake check areas, rest areas. 5-1-1, Adopt-a-highway... that's all on blue signs.

Even tsunami and hurricane evacuation routes there on blue signs as well. Emergency health care falls in this category. You can put logos up there directing people to hospitals and pharmacies.

That's a good idea, but both have to be open. Twenty four seven. (CVS:) "Oh, man!" And the pharmacy has to be within three miles. Rural traffic and weather information can go on a blue sign, although it's typically just an automated loop.

(DJ babble: Something about Portland being rainy all the time) But seriously— in the manual, rule number one, it's on page one says: "Traffic control devices or their supports shall not bear any advertising message.". So what's a Ruby's Diner sign doing on there? Logos are super banned on highway signs. When Albany started putting the "I Heart New York" logo on highway signs...

(Former governor:) "Promoting the assets of New York". Federal Highway Administration came down hard. They said the signs were distracting and had too much information on them, like web addresses, unauthorized logos, and a call to download the state's tourism app— while you're driving 65! FHWA threatened to withhold $14 million. After a little bit of fighting, New York took the signs down. So it's no joke when I say the MUTCD only allows two kinds of logos: One is for branded toll facilities.

Electronic tolling. Toll passes instead of toll booths. The color purple is also reserved for this.

For more details, check out one of my earlier videos on tolling by clicking the link above or below in the show notes. The second type of acceptable logos are on SPECIFIC SERVICE signs. Just like their General Service Sign brothers, these blue traffic control devices with white text also inform drivers which services to expect at an off ramp. Only difference is: these signs mention specific businesses.

But only for qualified food, lodging, gas, camping, and attractions. Let's say you own a gas station and you really want to get your logo onto that sign. Well, what does it take to make that happen? It depends on which state you live in. Each one charges fees to make and maintain a logo. Prices vary. States individually determine who qualifies based on operating hours, distance off the freeway, or even defining what an attraction is.

California uses a point system which rewards a business that is far away from other similar businesses. The state is so populated, most businesses score too low to qualify, which is why you don't see many specific service lines here out of L.A. You have to drive a good way toward Las Vegas before you start seeing some. This is Google Street view of it, because I didn't want to drive that far.

Up next: recreation signs. These are very similar to signs for services, except they're brown. Remember, a traffic control device is also for pedestrians. Although the Forest Service prefers to call them hikers.

White text and over 120 symbols representing different types of recreation and cultural interest. Signs like these guide people to recreation areas that are open to the public. Places like lakes and parks and hiking trails, museums, even ski areas, all with a nice natural color designed not to take you out of nature— in the same spirit of the non traffic control devices that the Forest Service uses. (Goofy:) "Away from it all." Unless you like it all. These are so similar to blue signs that there are not a ton of rules.

Just use the same good practices you would for signs of other colors. Recreation signs can either use text or they can use little icons, including a little horse to represent equestrian centers. This sign shows text it's perfectly good, except they added a little icon underneath anyway.

One they made themselves on a green background for some reason. (Sarcastic:) "Ride a horse or else you're getting a ticket.". This video is already incredibly long, which is why it's also incredibly late coming out. I must emphasize how little of the MUTCD we've covered.

We've only been talking about the sign part. There's an equally-large section on pavement markings, on highway traffic signals, and stoplights, rules for roads that don't see a lot of traffic. The do's and don'ts for construction zones.

An entire section on school crossings, railroad crossings and a whole park just for bicycle ways. Here's an itty-bitty regulatory sign just for bicycle. The existing MUTCD has been around well over a decade, and right now the Federal Highway Administration is working on an in-depth addition, which should be out in a couple of years with over 600 proposed changes. Transportation engineering is never ending.

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2021-12-15

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