12/20/2021
Have you ever wondered how traffic control devices evolved?
With the arrival of the “horseless carriage” in the early 1900’s, the first road signs have been helping direct travelers to their destinations.
The evolution of road signs provides fascinating insight into, not only the evolution of traffic devices but social and economic conditions as well…
Early on many drivers would find that if directional signs existed many were broken, unreadable or knocked down. Any road signs that did exist were erected and maintained by private citizens.
Without any regulation one might see many thoroughfares with multiple signs for a single trail or route…
Automobile clubs were working on getting roads properly marked…early on in some cases there were actual signs and in others there may be colored bands around a utility pole.
Other entities began developing devices to help control the flow of traffic…some of the notable firsts are:
-In 1911 a road in Michigan was the first to have a centerline on it
-In 1914 the first electric traffic signal is installed
-In 1915 the first “STOP” sign appears in Detroit
-In 1916 the US government requires states to have a highway department to receive federal funds
-In 1918 Wisconsin is the first state to put up official route signs as a maintenance function
-In 1920 the first 3-color traffic signal is installed in Detroit
In the early 1920’s the states of Wisconsin, Minnesota & Indiana teamed up and toured several states with the intention of developing a standard of uniform signs & road markings. The information that was supplied from that study helped develop some of the standards that are still used today.
They developed a plan to classify sign shapes according to the level of danger a situation may represent.
For example, round signs warn of approaching railroad crossings. An octagon represented the next level of danger, the need to STOP at an intersection. The diamond was chosen for less dangerous, but still cautious situations, and rectangles supplied regulatory information and the shapes make sense because drivers could respond to the shape even if they might not be able to read the sign…
All signs were black lettering on a white background and limited in size to 24” in size.
In 1924 there was a recommendation to include yellow and red into the standard colors, yellow was an indication danger or caution situations. However, the red was rejected because of inadequate visibility at night. This was also the first time the shield was proposed for use on highways.
In 1927 the first guidebook only addressed use & design on rural roads which was then expanded to include other categories, allow for red lettering on a yellow background for STOP signs and smaller signs in urban areas.
By 1932 in had become apparent that having two entities writing a sign manual was confusing things. So the Joint Committee on Uniform Traffic Devices was formed and the first Manual of Uniform Traffic Devices (MUTCD) was mimeographed. Demand for the manual was so great that the first printed version was published in 1937 with 166 pages separated into four parts: addressed signs, markings, signals & islands
The 1935 edition of the MUTCD did set the standard for types of signs: regulatory, warning or guide signs. As well as pavement makings including symbols & their sizing, colors, curves & radiuses.
The MUTCD has seen revisions numerous times…In 1935 recommended changes in sign illumination, speed signs, no-passing zone pavement markings, signal warrants, and pedestrian signals.
In 1942 the MUTCD revision addressed the types traffic control devices to be used during blackout conditions resulting from the war.
In 1948 the MUTCD underwent a major format change, simplifying, reorganizing and alphabetizing the material and a rounded-letter alphabet was adopted as a sign standard.
In 1954 a 15-page supplement to the MUTCD included 47 revisions, the most notable of which was the “STOP” sign was changed to white lettering on a red background and white lettering on a green background was adopted for guide signs.
In 1961 the MUTCD had two new sections added, one was for construction projects and the other addressed maintenance operations.
A similar thing happened in 1971…the MUTCD got a complete re-write. Orange was designated as the backing color for construction signs, school signs were added and yellow markings were designated to separate opposing traffic.
Coincidentally, much like 1961 two sections were added to the MUTCD in 1978…highway-rail grade crossings and traffic control for bicycles
Since then the MUTCD has remained a dynamic document that is constantly amended to accommodate the ever changing conditions of increased recreational & commercial traffic, higher speeds and advancing technology.
https://mutcd.fhwa.dot.gov/mutcd_news.htm
