Speed Limit Signs - a History of Speeding in the US

Early Speed Limit Signs

As cars have become faster, speed limit signs have naturally kept up. The first speed limit signs were posted at city and town limits. Early signs were not reflective. By the middle to late 20’s however, many cities required that speed limit signs be illuminated. The early requirement was for a famous GE style of light, called a “MAZDA” lamp. The New York State legislature, in 1925, passed a law that "each city shall have placed conspicuously [signs on] each main highway, where the rate of speed changes [and signs shall be] adequately illuminated between sunset and sunrise".
For many townships and cities, however, internal illumination proved difficult. Too many roads needed speed limit signs and power was not readily available. As a result, speed limit signs started to use “cats eye” reflectors. Signs with reflectors captured the light from early auto headlights and reflected the message back to the driver.
Speed Limit Arrow Sign
Arrow sign is used to designate a road near a schoolhouse and limits speeds to 10 MPH. The arrows are from July, 1925 American City Magazine, "Traffic Regulation and Directions", which showed recommendations from the International Police Conference.
Speed Limit Sign 20 MPH from 1925
Different cities were free to enact different speed limits. This sign is shown from the Lyle Sign Catalog of 1925. Note the use of cats eye reflectors.
By the late 1920’s however, the interstate system adopted signs which initiated many of the design elements that we see today on our current Speed Limit sign designs. The signs were rectangular, taller than wide, printed in black and white and highlighted the actual numerical speed limit in taller letters. Rectangular signs “are used to carry direction of use or benefit to the driver” (1927 AASHO). AASHO also cited that the dimensions of Speed Limit signs (a tall rectangle) distinguish them from other directional signs.
1925 Speed Limit Sign
1927 Speed Limit Sign AASHO R-4
Speed Limit Sign from the 1930's
Photo of a speed limit sign from the 1930’s (in author’s collection).
Speed Limit Sign adapted by the Joint Board of Interstate Highways, as reported by the American City Magazine, 1925. The middle sign shows the AASHO R4 Sign from 1927.
But, most early roads were not part of the nascent interstate system, nor were they part of a city’s street network. These early roads, which still transverse rural communities, seldom posted signs. For many, the “honor system” was predominant.
Vintage Speed Limit Sign from Redditpics
Vintage Speed Limit Sign from Redditpics.
Speed Limit Sign for 1930's Speed Patrol Area
By the late 20’s and 30’s, speed patrols become more common (Photo from the Author’s Collection).
The debate between those demanding the freedom to travel at high speeds in an unregulated environment and others citing the need for greater security and increased regulation (e.g. signs) was common in the 20’s and 30’s. For certain communities, "too slow speeds” were also an issue. As reported in the June, 1925 Lyle Sign Post, the chairman of the Maryland State Roads Commission, John Mackall, "advises substitution of the maximum speed limit with a minimum speed limit, to speed up traffic. Mackall also suggested slow-moving vehicles be barred from main streets during peak hours".
Many states did not require drivers licenses. As part of the author’s own family lore, there is a wonderful story of two strong-willed daughters, Lydia and Mary, traveling from their home in North Dakota to visit their father, Senator Langer, in Washington, DC. With little experience, other than on farm machinery and certainly no license, they ended up in Washington in record time. Speed limits (and the few Speed Limit Signs) were proudly ignored.
For more discussion, see the excerpt below on fixed speed limits: "Should there be Fixed Speed Limits?". Even in the 30’s and 40’s, speed limits were not uniform. Should speed limits change, depending upon the weather conditions, road conditions and time of day (for example, during school hours)?
Speed Limit Sign 1959
1959 (Author’s Collection).
Metric Speed Limit Sign from 1975
A speed limit sign in Washington from 1975 that includes a metric limit and warns drivers that it is radar enforced (Photo in Author’s collection).
It was not uncommon to find that speed limit regulations changed from jurisdiction to jurisdiction. Towns often found themselves at odds with neighboring communities. Moreover enforcement was also inconsistent. See the 1927 excerpt below from one Mayor’s reported leniency towards speeders. In spite of this speed limit variability, school zones and pedestrian areas have always been more tightly regulated.

Modern Speed Limit Signs

The 1930 NCSH and 1935 MUTCD manuals defined the Speed Limit signs with most modern elements. The first mention of the yellow "advisory speed limit sign" occurred in the 1935 MUTCD. And in 1948, the MUTCD specification specified, essentially, all elements of the current speed limit sign. The code R-2 and R-102 were defined in 1948 for the two sizes and colors of Speed Limit Signs.
From 1930 NCSH Urban Manual
From 1930 NCSH Urban Manual. This 24” x 30” sign uses three different fonts.
10 mph 1930 NCSH Urban Manual
Modern Speed Limit Sign
The modern speed limit sign (at right) was largely established and specified in the 1948 MUTCD. Yellow advisory speed limit signs were also defined in the 1948 manual.
Some excerpts on the changing specifications for the speed limit signs are as follows:
1930 NCSH Urban Manual. Sign size and font defined 30" x 24" [sign and the words] Speed Limit shall be in 3 1/2 inch Series E letters, the numerals shall be in 8" Series F letters and word "Miles" entry in 3" Series D letters.
1935 MUTCD (Signs Placed Where Speeds Change). Speed limit signs shall be erected on main thoroughfares at entrances to business or residential districts in municipalities and at other points were established prima facie limits are changed. It should be noted that the speed limits indicated in uniform vehicle code are prima facie limits. Therefore, where the code is in effect speed limit signs will indicate the maximum presumptively proper speed under normal conditions. It is frequently desirable to erect confirmatory speed limit signs at selected points within speed zones.
1948 MUTCD (Yellow Advisory Speed Limit Sign Defined). The advisory speed sign is a small plate, 13" x 30" square with a message [xx] mph in black on a yellow background. It may be used in conjunction with any standard yellow warning signs to indicate the maximum safe speed around a curve or through a hazardous location.
Another sidelight to the inevitable march towards state, county and local governmental standardization of speed limit signs was the desire to bring the metric system to the US. The FHWA received a crushingly negative response to this conversion and it was dropped in 1994.

The "Cat and Mouse Game" – the Police Radar Gun vs the Speeders

Law enforcement officials attempt to deter dangerous speeding by handing out tickets to speed limit violators. This type of regulation was not so easy in the beginning. Police officers had to be sure that violating vehicles were travelling well above the legal speed limit before they could pull these miscreants over and slap them with a ticket. Before the use of radar, such certainty was virtually impossible. Then, much to the chagrin of speedsters, came the invention of the radar gun.
Using a Radar Gun to catch Speeders - Chicago, 1956
Police officers using a clunky radar gun to catch speeding drivers in Chicago in 1956 (Photo in author's collection).
Created by Bryce K. Brown of Decatur Electronics, the first radar guns calculated the speed of objects by measuring the change in frequency of waves hiting moving objects due to the Doppler Effect. In April 1954, the first speeding ticket using the new radar device was issued by patrolman Leonard Baldy in Chicago, Illinois. Since its invention in 1954, radar speed gun have been used by police officers to measure the speeds of passing cars, and catch drivers who violate the lawful limit.
Radar gun used by police officer to catch speeding drivers
Leonard Baldy, the first police officer to use a radar gun to issue a speeding ticket, on the job with his radar gun in Chicago in 1954 (Photo in author's collection).
Speeding ticket from 1954 – speeder caught using new radar system
Two officers issue a ticket to a Chicagoan who was caught driving 36 mph in 25 mph zone by a radar gun in 1954. This was described as the first speeding ticket resulting from radar enforcement (Photo in author's collection).
Radar guns quickly expanded their electromagnetic reach from Chicago to the rest of the country, becoming a fixture of many American police forces. The first radar gun was large and unwieldy, and it looked somewhat like a telephone. Newer models were handheld and more easily transportable.
As they do, law-breakers eventually found a work-around – in this case, the Fuzzbuster. Invented in the 1970’s, the Fuzzbuster could detect police radar, and warn drivers to slow down when approaching a speed trap. In response to devices like the Fuzzbuster, police officers now use the more modern LIDAR speed gun, which uses laser waves instead of radar light waves. Radar guns and devices like them ushered in a new era of speeding tickets, in which American drivers, by choice or by law, grew more and more alert to speed limits, as posted on signs along the road.

The Need for Speed

Did you know that until 2010 there was a highway from Abu Dhabi to Dubai with a posted speed limit of 99 miles per hour? The speed limit in opulent Abu Dhabi was lowered to 87 miles per hour this year, but there are still plenty of roads in the country that do not regulate driving speeds. In contrast, in the United States, the fastest any driver is legally allowed to drive is now 85 mph; this limit is for rural roads in Texas, where apparently everything really is bigger, even the speed limits. Speeding is the most frequently cited aggressive driving violation, so it’s no surprise that speed limit signs aimed at slowing drivers and reducing accidents heavily adorn almost every American road. Speeding is still a major public safety concern, but new technologies have made it easier for the police to deter speeding by issuing ticket to those who violate the speed limit.
Funny Texas Speed Limit 100 Sign
This tongue in cheek sign pokes fun at Texas for allowing such high speed limits.
Nevada Speed Limit Signs Changed
Workers at Nevada’s Department of Transportation creating new signs after the speed limit was raised in 1995.
First instituted in 1901, speed limits are assigned to increase road safety and reduce the risk of traffic collisions. For a long period, individual states were responsible for determining their own speed limit laws. After oil shortages in the 1970s, Congress established a national maximum speed limit of 55 mph. New, federal mandate for speed limits was signed into law by President Richard Nixon, and adopted by every U.S. state in 1974. Congress bumped the national limit by 10 mph in 1987, but repealed the law less than ten years later, returning speed limit responsibility to the states in 1995. Since then, 34 states have raised speed limits to 70 mph or above on some part of their roadway systems.
With the expansion of road systems in the first half of the 20th century, speed limits – and speed limit signs – had already grown vitally important to the safety of American citizens. By the 1940s, manufacturers were experimenting with different designs for speed limit signs.
Speed Limit Signs Changed from 35 to 45 mph in Chicago, 1947
Traffic Supervisors in Chicago repainting and changing speed limit signs from 35 mph to 45 mph in 1947. These signs are a slightly unconventional design (Author's collection).
By the time Carter and Nixon nationalized the speed limit, however, speed limit sign design was pretty much nationalized. The standardized black and white design was, at this point, the predominant standard for most jurisdiction. What was less clear was how to ensure that speed limit signs were visible to vehicles at night. According to a 1925 article by T.P. Brown in The Sign Post, most cities and towns used flood-light projectors or reflectors equipped with lamps to illuminate signs and promote nighttime road safety (Author Archives: The Sign Post: Number V, June 1925). Nowadays, speed limit signs are made with different grades of highly reflective aluminum—from engineer grade to high-intensity grade to diamond grade as the most reflective—so that any driver properly using his/her car’s headlights would be able to see them at any and every hour of the night.
Reflective speed limit sign visible in the day
This tongue in cheek sign pokes fun at Texas for allowing such high speed limits.
Reflective speed limit sign visible in the night
This speed limit sign from roadtrafficsigns.com is highly reflective and can be seen in the dark. This is a non-standard sign.
The fact that drivers can see speed limit signs does not mean that they will obey them. Speeding is a major threat to road safety; according to the NHTSA, excessive speed contributes to approximately one of every three fatal crashes, and it is the third leading contributor to all car crashes. Speeding accounts for more than 13,000 deaths a year, and the NHTSA estimates that speeding-related crashes cost society over $40 billion a year. Though it’s clearly a dangerous activity, almost all drivers speed.
1966 Speeding Is Costly Sign tells drivers the costs of speeding
A 1966 “Speeding Is Costly” sign reminds Detroit drivers of the costs of speeding (Author’s collection).

Conclusion – Speed Limit Signs Become Complex

It’s been over 100 years since the introduction of automobiles. As cars have become faster and roads safer, speed limit signs have changed in parallel. Historically, car travel meant freedom - you traveled where and how fast your thought safe. With time, however, speed limit regulations became ever more complex, precise and law bound. Speed limit signs follow the same trends with changeable speeds depending upon pavement conditions, whether school is letting out and the kind of truck or car you are driving. Rules, politics and enforcement are all more complex than before. Speed limit signs simply follow these trends.

Should there be Fixed Speed Limits?

Judge Upholds 51 - Mile Speed [Excerpt from Sign Post,
February, 1927]
Common Pleas Judge E. P. Middletown of Urbana, Ohio, has decided that dangerous speeds from an Automobile depends wholly upon conditions.
Judge Middletown held this:
"A driver may go 45 miles an hour and still not be guilty of speeding, if the pavement is dry, the road clear and his car in good mechanical condition."
The ruling was made in the case of the State of Ohio against a driver of a bus.
There was another little known fact brought out in the case—that magistrate courts do not have final jurisdiction in speed cases. Magistrate S. M. Pence bound Larrick over to the grand jury.
Larrick, the driver, was indicted, tried and found not guilty.
Although Larrick traveled in excess of 35 miles an hour and at a rate ''greater than is reasonable and proper," it was learned the machine he was driving was in good mechanical repair and that there was a straight stretch of improved road for several miles with no obstruction in view and that the road was from 20 to 27 feet wide, with no traffic to be seen. Although the speed attained was prima facie evidence of violation, it was these conditions which governed the situation and brought forth the ruling from Judge Middletown, which continued:
"The question naturally arises, what speed is reasonable and proper? Obviously, a driver traveling at the rate of 45 miles an hour along a deserted country highway, with a few cross-roads and dry pavement, would not be guilty of a speed greater than is reasonable and proper. The fact that he has exceeded the 35-mile speed is merely presumptive evidence, according to the statute, that he has violated the law.
"If the same driver would attempt to pass a country school house during recess, or at a time when school was being dismissed, at a rate of speed below even 15 miles an hour, he might be found guilty of traveling at a rate which was not reasonable and proper, and could quite properly be arrested for exceeding the speed limit."
Things have reached such a state in Chicago that when a man is killed by a motor-car or shot by "thugs" they return a verdict of natural causes. - Punch

Give a Ticket or a Warning?

SPEEDERS HEED PLEA OF IOWA MAYOR [Excerpt from Sign Post, February, 1927]
Spencer, Iowa, a city of 5,000, crossroads of two important highways, center of a network of gravel roads, has found that Mayor A. H. Avery's policy of kindness to auto speeders has effectively reduced traffic dangers.
Mayor Avery took office April 1, after a campaign in which he made an issue of the vigilant trailing and fining of auto speeders by his predecessor. On June 1, after discharging the speed cop, Mayor Avery launched his plan of writing offenders a friendly, courteous letter of warning. Since then 200 letters have been written. A second one has never been found necessary. Spencer has regained the friends it lost through its previous stringent policy. Mayor Avery believes a speeder is not a criminal and hence should not have a court record unless he persists in fast driving. After a speeder has been warned once he is fined the second offense, although a second complaint has not yet been made.
The Judge: "You are charged with running your car sixty miles an hour, smashing a telephone pole and a plate glass window, and injuring six people. What have you to say?" The Offender: "Great Scott, Judge, doesn’t the fifteen dollars I pay for my license enable me to any privileges at all?"
Give a Ticket or a Warning