The Manual on Uniform Traffic Control Devices (MUTCD) is widely considered to be a dry and unemotional document. Published by the Department of Transportation, it outlines the basic specifications of all the street signs you could expect to see out on roads and highways across the United States. Most are familiar, but if you dive deeper into its pages, you can find some unsettling relics from darker times.
Back in the mid-20th century, America was tangling with the realities of nuclear war. Top generals contemplated targeting strategies, while engineers mused over whether there was anything to be done top stop a torrent of enemy missiles falling across the nation. These superweapons seemed to promise destruction on an overbearing scale, threatening the very existence of human civilization itself.
Against this bleak backdrop, government administrators turned to the concept of Civil Defense. The idea was to do whatever could be done to protect the citizens of the nation from the horrors of nuclear war and its immediate aftermath. In turn, the Department of Transport worked up some rather depressing road signs to help people get where they needed to be in these bleak and trying times.
Flip open the 1961 edition of the MUTCD, and you’ll find an important section on Civil Defense. It featured a handful of designs for traffic management in a post-nuclear world. Perhaps most interesting was the “MAINTAIN TOP SAFE SPEED” sign, designated CD-4. It’s purpose was highly unique:
The “MAINTAIN TOP SAFE SPEED” sign may be used on highways where radiological contamination is such as to limit the permissable exposure time for occupants of vehicles passing through the area. Since any speed zoning would be impractical under such emergency conditions, no minimum speed limit can be prescribed by the sign in numerical terms. Where traffic is supervised by a traffic regulation post, official instructions will usually be given verbally, and the sign will serve as an occasional reminder of the urgent need for all reasonable speed.
Basically, if you saw this sign, you’re supposed to be gunning it as fast as you can while still staying on the road. The intention is to limit your exposure to radiation as much as possible while traveling through contaminated areas.
The 1971 edition of the MUTCD expanded further on the Civil Defense section. The DOT had by this time developed a standardized sign for marking directions to fallout shelters, where citizens could wait out radioactive contamination falling from the sky after a nuclear attack. The document also specified a sign for decontamination centers, where those suffering radiation exposure might be treated by experienced personnel.
Further signs in this series include the “AREA CLOSED” sign used to designate areas of high radiological or biological contamination that are too unsafe for travel. The DOT also specified a blue “Evacuation Route” sign marked with the Civil Defense logo. It was intended to guide citizens to safety along pre-planned routes.
Ultimately, the Department of Transport prepared these signs for when things really hit the fan. Thankfully, the worst fears of the Cold War never came to pass, and these signs weren’t needed in any major emergency situation.
And yet! Some of these signs persist in the MUTCD standard to the day. The most recent edition still includes some of these signs—like EM4-1b ‘FALLOUT SHELTER’—but now places them under the category of Emergency Management signs. The bleak term of “Civil Defense” is no longer very relevant in government administrative circles.
Us car enthusiasts do like driving fast. Still, when the government has put out a sign telling you to floor it, you know the situation has to be dire. In the end, most of these signs have never been put to use, and that’s something we can all be thankful for. Regardless, the Department of Transport stands ready with signage prepared to deal with whatever might happen down the line.
Image credits: Department of Transport, top shot logobom/depositphotos.com
I thought the MAINTAIN TOP SAFE SPEED sign was for women wearing bikinis and driving convertibles.
A whole piece from Lewin on this and yet not a single reference to this signage?! What is pre-apocalyptic Australia coming to??
https://images.app.goo.gl/94Bei1fWi2C925uK6
This is the perfect speed zone sign for Cannonballers.
” IF YOU CAN READ THIS, YOU’RE TOO SLOW!”
*picture of Blinky with 3 X’d eyes*
This is fascinating. But I kinda feel like if I’m escaping nuclear fallout, I don’t really need the sign.
On the other hand, if you see this sign and you think you’re going to die, choose your destination carefully because it turns out they’re in opposite directions:
https://live.staticflickr.com/6129/5930012541_414340e1d2_c.jpg
Variations of other road signs that might also be useful:
“Keep Windows Closed At All Times”
“Put your AC on “recirculate.””
“No Hitchiking. Mutants Ahead.”
“Hitchhikers May Be Radioactive Flesh-Eating Zombies”
“Caution, Falling Fallout Ahead.”
Aliens in this area.
Do not stop.
Hitch hikers may not be what they appear to be.
In case of fallout place your head between your legs and kiss your ass goodbye. Note if you can’t bend that much kiss your passengers ass goodbye.
This reminds me of that image of the cylinder of Cobalt-60 stamped with the words “DANGER RADIATION – DROP AND RUN”
Those rods are pretty small and the typeset smaller.
Pretty sure by the time you’ve made out the words and the message had sunk in you’d be looking at a real bad time.
I feel like I saw a bunch of these around Devil’s Tower a few years back.
That was more than 50 years ago they had that chemical spill out there. I bought a canary so I made it out OK. Don’t know whatever happened to that one guy I saw, though.
These sections were still in the MUTCD until the Millenium Edition update in 2000. While regular signs have materials and visibilty standards, the emergency signs could be made from whatever durable materials were handy.
I HAVE to find a “maintain top safe speed” sign for my garage
I have a windshield decal on my 68 Charger that reads “DEEPS EFAS POT NIATNIAM”
Now we have electronic signs for civil defense needs: https://www.theledger.com/story/news/2009/12/23/dot-zombie-warning-sign-work-of-hacker/26236498007/
So, basically, after a nuclear holocaust, some road crew would have to run around and swap out highway signs so postapocalyptic commuters or road trippers would know not to be afraid of getting a speeding ticket from the cop hiding behind the pile of crumbled concrete that used to be a mall?
They also assumed enough personal vehicles would be functional, which, I guess, in the days of simple electronics was a bit more likely than it is now
I’m guessing that they were planning on a scenario where, after a radiological disaster (not necessarily a nuclear strike), roadways through affected areas would simply be closed. At some point, authorities would have to determine if certain roads could be re-opened for use, knowing that contamination would be present for decades or centuries. Hence the signs – if you have to use this road, haul ass.
Not so much about tickets. Really more of a “Stop looking out the window at the scenery and step on it if you don’t want a third arm to grow out of your forehead.”