On 10 December 1868 the world’s first traffic lights appeared outside the Houses of Parliament in London to control traffic flow around the new Parliament Square.
The lights were designed by J P Knight, a railway signalling engineer. They used semaphore arms to direct the traffic during the day, and red and green gas lamps at night, all operated by a police constable.
John Peake Knight, the man behind the first traffic light. Credit: J.P Knight Museum
Unfortunately, despite their success at directing traffic, the first lights didn’t last all that long. A leak in the gas line caused them to explode, in so doing reportedly killing the police operator. It would be another thirty years before traffic lights really took off, this time in America where semaphore lights sprung up in various designs across the different states.
In 1888 and 1889, a vicious serial killer haunted the streets of London. To this day the identity of the murderer is unknown, but he has a name – Jack The Ripper.Watch Now
It wasn’t until 1914 that the first electric traffic light was developed, in Salt Lake City by policeman Lester Wire. In 1918 the first three-colour lights appeared in New York City. They arrived in London in 1925, located at the junction of St James’s Street and Piccadilly Circus. But these lights were still operated by a policeman using a series of switches. Wolverhampton was the first place in Britain to acquire automated lights, in Princess Square in 1926.
A complete history of the traffic signal
The evolution of the traffic light can be traced back some 200 years, but before becoming the reliable system we know today it has had to recover from a number of design flaws and evolutionary dead-ends – as well as all-out explosions. In this exclusive extract from his new book Traffic Signals, Alistair Gollop (pictured), senior ITS consultant at Mott MacDonald, presents what is perhaps the most complete history of traffic signal design ever compiled. It is just the first chapter of the book, which is a comprehensive guide to traffic signals, from first principles and design issues, to equipment and testing, commissioning and assessments. It is a complete introduction to the subject and likely to be of interest to traffic management practitioners of all levels.
A lot of people are surprised to find out that the history of traffic signalisation pre-dates the advent of motorised vehicles. The technologies that lie at the root of this actually emanate from research work undertaken by the British Admiralty, for Communications and Maritime Navigation.
To enable the Admiralty in London to communicate quickly with the naval ports along the south coast of England, a chain of optical telegraph stations were erected in the late 18th century.
The operation of the telegraph was further improved by work undertaken by General Pasley in the early 19th century, who observed the system perfected in France by Claude Chappe, which resulted in the adoption of the semaphore style of telegraph from 1816 in the UK. (a restored Chappe telegraph station in St Marcan, France, is pictured)
In later life, General Pasley became Inspector General of Railways and during this time, in response to rising accident rates, suggested the use of the semaphore signal as a means of improving communication with locomotive drivers. The first of these was erected by Charles Gregory of the London and Croydon Railway at New Cross in 1842.
With the introduction of steam ships in the mid-19th century, there was a huge increase of collisions at sea, resulting in many ships being lost. Following the work of a Parliamentary Select Committee which first looked at the issue in 1831, a number of studies were carried out. These included investigating the use of coloured lights to make the direction a ship is travelling in more apparent to other vessels after dark. It was found that oil lamps with clear, red and green lenses could be viewed from the greatest distance, with minimal risk of misinterpretation. The outcome of this study was the recommendation that red and green lights should be used as navigation sidelights on vessels, which were adopted universally in 1858.
These two bodies of work, which were leading edge technologies at the time, resulted in two sets of developments:
• The widespread adoption of semaphore signals to control traffic on the railways
• The use of red and green lights as visual warning signals
In the mid-19th century, traffic congestion in London was getting worse and, in response to a suggestion made by a Parliamentary Select Committee, the first traffic signal in the world was installed in Bridge St, adjacent to the Houses of Parliament, in December 1868. This was undertaken to enable MPs to cross over this busy street.
The signal, which was promoted by railway engineer J P Knight (pictured with his design), who lived nearby in Bridge Street, was over 20ft (6m) high. When the semaphore arm was extended horizontally it meant ‘stop’, and when lowered to 45-degrees it meant ‘proceed with caution’. At the top of the pole were red and green gaslights, which were used to augment the arm at night. The operation of the signals was controlled manually by a police officer turning a handle. Unfortunately, the signal didn’t last for long because on 2 January 1869, leaking gas in the signal caused it to explode. The police operator was injured in the incident, resulting in the installation being removed.
After this, the only other recorded traffic signal installation in the UK was part of the bridge interlocking system which controlled the lifting operation at Tower Bridge. The system (pictured below) was designed and manufactured by the railway signal firm of Saxby and Farmer, who had also made the earlier signal at Bridge Street. Included in the system were semaphore signals (also fitted with green and red gas lights) for both river and highway traffic, which worked in relation to the operation of the current bridge position. Part of the mounting bracket for the original signal is still visible today. Since opening in June 1894, the traffic signals have continued to control traffic flow on the bridge which arguably makes Tower Bridge the location which has been signalised for the longest period of time in the world.
No further attempts seem to have been made at mechanised traffic control, until the growth of motorised traffic in the U.S. lead to a need to control junctions in the early 20th century.
A plethora of differing signal systems were developed over the coming years, but these mainly fell into two families, semaphore arms and light signals. One of the most famous of the semaphore type of signal was patented in 1922 by inventor Garrett Morgan. His signal consisted of rotating arms, red and green lights and a bell (which warned of an impending change). Although this system was hand-cranked, it had the added sophistication of including an all-stop period between opposing traffic streams to allow the junction to clear. However, it soon became apparent that semaphore styles signals were an evolutionary dead end.
The first electric traffic light was invented by Lester Farnsworth Wire and installed in Salt Lake City in 1912. Lester was the head of the traffic division of the Salt Lake City Police Department. His signal (pictured right) had two lamps, one red and one green, and was installed in a large wooden box with two six-inch holes on each side. It was operated by a patrolman who used a two way switch to change the light’s colours. However, in this instance, the same signal was displayed to all approaches. The colour it illuminated (red or green) signified traffic could flow on a particular approach, i.e. north and southbound or east and westbound.
William Potts, a Detroit policeman, invented the first three-colour lights in 1920. His four-way signal head used railway signal lamps and was designed to be suspended over the centre of a junction to control traffic from four approaches. It was the first signal to resemble the operation we know today.
In England, the first manually controlled electric traffic lights were installed in Piccadilly, London, in 1925 and the first automatically controlled signals were installed in Princes Square, Wolverhampton in 1927. Today, this junction has specially painted black and white signal poles to commemorate its historic significance.
During the 1930’s, experiments were carried out in the use of vehicle actuation to make the traffic signals responsive to vehicles using a junction. An early attempt at this utilised a microphone placed at the side of the road, which would make the lights respond to motorists sounding their horns (left). Although this system worked, it was very unpopular with people living nearby.
Later experiments used electrical pressure mats and pneumatic tubes which were extensively used up to the 1970’s when they were replaced with inductive loops for permanent installations. However, pneumatic tubes are still used for temporary count sites, where they are fitted to the surface of the carriageway.
The first vehicle actuated site in the UK was installed in 1932, at Gracechurch St / Cornhill in London. Unfortunately, history repeated the events of 1869 when the controller blew up. In this case though, gas had seeped into the controller cabinet base, from a nearby leaking gas main, and was sparked by the electrical apparatus in the controller. However, on this occasion, the accident did not block the course of progress and within a couple of year’s vehicle actuated controllers were being used widely across the country.
In a second extract from Traffic Signals, to be published here on Traffic Technology Today next week, Alistair Gollop will look at what the future may hold for such systems.
Do you know what these terms refer to and the differences between them?
MAN, VA, FXT, CLF, UTC, SCOOT and MOVA
Traffic Signals: An introduction to signalised junctions and crossing facilities in the UK has the answers.
In addition to the history of pioneering signal development, Traffic Signals looks at the way in which modern signals operate and the equipment commonly used in current traffic control systems in the UK. It also looks at how signalised junctions and crossings are designed, explaining the fundamental design principles, and how these are used by modern software modelling tools to predict traffic operation.
Although it uses mainly examples for the UK, Traffic Signals will be of interest to traffic management practioners around the world.
Included within Traffic Signals is a handy set of standard detail drawings which are commonly used when specifying and designing projects.
Tom has edited Traffic Technology International magazine and the Traffic Technology Today website since May 2014. During his time at the title he has interviewed some of the top transportation chiefs in charge of public agencies around the world as well as chairmen and CEOs of multinational transportation technology corporations. Tom's early career saw him working on some the UK's leading consumer magazine titles. He has a law degree from the London School of Economics (LSE).
Road Traffic History - Before the Streets Got Swampedby Daniel Patrascu
All fine and dandy, but there is one little aspect we haven't talked about as much. One in the absence of which cars would be reduced to simple pieces of furniture, or to extravagant works of art. An aspect which does not exist in physical form, but often has more drastic consequences on the life of a person than a solid, tangible object: traffic rules.
Often annoying, seemingly pointless, traffic rules have been the automobile's silent companion for the better part of its existence. We will not give you here a stiff, to the point presentation of what traffic rules are today, or in your country, or whatever. As with any field of human activity, what matters here is what came first: first rule, first sign, first ticket, first crash and, unfortunately, first fatality. FIRST TRAFFIC LEGISLATION
When you read this, you should have in mind what the people of the time (1800s) understood by the term "traffic": no asphalt, no cars, no traffic lights, no traffic signs, no street markings, no traffic police.
Why then the need to create legislation to cover. nothing then?
With the industrial revolution still making its presence noticed, railroads and more importantly fields began being flooded with traction-engined vehicles (aka road locomotives). To get from place to place, locomotives had to cross urban, populated ares and, despite the fact the were slow, noisy and impossible to miss, they posed quite a threat to the innocent bystanders. Or horses.
Scared by the prospects of a respectable citizen getting squashed, as well as by the prospects of hearing one of the damn things huffing and puffing in the quiet of the night, the British Parliament adopted what became know as the Locomotive on Highways Act, in 1861.
The provisions of the legislation seem somewhat hilarious now as some have lost their significance over time. A few, however, have formed the basis for today's traffic legislation.
The legislation, for instance, only stated that the vehicles' weight should be at most 12 tons and imposed a 10 mph (16kph) speed limit. No idea how they knew a vehicle is speeding.
In 1865, the act is revised and turned into the Locomotive Act (aka Red Flag Act). It required that a motorized vehicle, regardless of its purpose, be preceded by a man carrying a red flag when traveling on the highway - Brits use the highway term for any type of road, including streets and public footpaths.
Speed limits were reduced to 4 mph (6 kph) in non-urban areas and at 2 mph (3 kph) in cities (still no idea how they caught speeding vehicles "in the act"). But the most important addition was the requirement to use at least three people to operate a vehicle: one to drive, a stoker, and one carrying a red flag (hence, the name of the bill) and a lantern.
The one with the flag was used for two purposes: he slowed the vehicle down, as it was forced to drive at walking speed, and warned approaching pedestrians and horse riders of their presence. Of course, you need to have been blind and deaf to miss one on the street.
In 1896, the revised Locomotives on Highways Act (or the Emancipation Act ) eliminates the need for a three man crew, increases speed limits to 14 mph (22 kph) and, more importantly, establishes the light locomotives category or, as we know it today, the under 3 ton class.
To celebrate the legislation, its creator, Harry Lawson, set up the London to Brighton Run, now the longest-running auto event in the world. FIRST LICENSE PLATES
As the number of vehicles on the roads increased, so did the authorities' need to keep track of them and their owners. The first country to use them is reportedly France, which issued one in 1893. But the one that established an entire system for them was the Netherlands, responsible for the first nationwide licensing system. Called driving permit, the system used numbers.
In the US, New York is the first to require license plates (1901). They were not government issued, but created by the vehicles' owners. Two years later, Massachusetts issues the first US state-issued plates.FIRST DRIVER LICENSE
Whereas up until the 1900s just about every single piece of legislation imposed limits and requirements for the vehicles themselves, all will change starting 1904.
In the UK, the habit of having a license plate described above turns law in 1904, when the Motor Car Act is adopted.
For the first time, the term of reckless driving is introduced, also stating penalties for the guilty party. If the driver did not display the license plate of his car, he would also be guilty of an offense.
Fortunately, for the first time, a license to drive was required. Unfortunately, there was no exam to take and the license was obtained just by paying five shillings and completing a form. FIRST TRAFIC LIGHTS
Prior to the introduction of the mandatory, get it yourself driver's license, the Brits introduced the first traffic lights. Even if the first road signs came into existence in the city of Ur (Iraq) some 4,000 years BC, for obvious reasons the first traffic lights were not possible until the late 1800s.
Credited to be the first is a two-color (red and green) sign, installed outside the British Parliament. It did not use electricity to function, but rather gas, and needed to be switched manually. Reports say that, a month into service, the traffic light exploded. It was never recreated again.
The idea however was good, so it was revived in the US in 1912 by Lester Wire, the man considered the inventor of the electric red-green traffic light. The first one was installed in 1914 on the corner of East 105th Street and Euclid Avenue in Cleveland, Ohio. The three-color light came as a natural evolution in 1920, at the hands of William Potts.
Linking traffic lights together was first done in Salt Lake City, in 1917, when traffic in six intersections was controlled by a switch. Automated traffic lights surfaced in 1922, in Houston. Five years later, the country which started it all, Britain, got its first lights in Wolverhampton.
FIRST TRAFFIC SIGN SYSTEM
As we said above, traffic signs, in the general sense, have been around for millennia. True, they only came in the form of erected stone columns or road side rocks which marked various distances to important urban centers. But they only informed, and not guided the travelers.
The first road sign system in its modern sense is said to have been created in 1895 by the Italian Touring Club, but there is little known about its provisions. Only in 1909, nine European countries agreed to use the same signs to indicate road attributes like "bump", "curve", or "intersection." Work on a unified, complete system continues to this day, even if it has been around since the 1950s.
In the U.S., the adoption of the international system began in the 1960s. Until then, the US used its own sign system. RIGHT/LEFT SIDE OF ROAD
Have you ever wondered why is it most countries drive on the right side on the road, in the direction of travel, and others do it on the left? Why did the Brits get it all wrong?
Well, actually, the rest of the world got it all wrong. Historically speaking, at least. Some archaeological findings in England tend to suggest that the Romans used the left side of the road to travel. Why?
The main reason, as suggested by historian Northcote Parkinson, is the human physiology. With most humans being right-handed, it was easier for a horse rider to travel on the left side of the road. By doing so, he could easily fend off attackers, as well as reaching to shake hands with friends.
According to the same historians, just about everyone travelled on the left until the 1700s. In 1756, the first documented road use restriction stated that traffic on the London Bridge is to stay on the left side.
The rest of the world began switching sides in early 1800s, as freight wagons drivers found it easier to clear incoming wagons by using the right side of the road (because drivers were usually seated on the last horse on the left, so it was easier for them to estimate the distance if the other wagon passed closed to him).
Today, most countries use the right side of the road to travel, with only aboput 75 still sticking to left-hand drive.
History of Traffic Lights: 100th Anniversary of the First Electric Traffic System
The 100<sup>th anniversary of the first electric traffic light system will be marked on 5 August.
It was installed on the corner of East 105th Street and Euclid Avenue in Cleveland, Ohio, and had red and green lights and a buzzer to provide a warning that the colours were about the change.
Traffic signals' birth in London
The idea for traffic lights began in the 1800s when a system was required to control the ever-increasing flow of horse-drawn traffic. In 1868, in London, a signal was installed at the intersection of George Street and Bridge street, near Parliament. This provided pedestrians a safe crossing.
The system installed – a semaphore – involved a tall post with moveable arms. When the arms were positioned sideways it meant stop. After dark, a gas light was lit at the top. The green tinted lens meant go, while red meant stop.
Signals were initially controlled by hand, with officers deciding when the signals should be changed according to traffic flow. They would blow a whistle to warn drivers that the signal was going to change.
However, this method turned out to be unsafe. In 1869, a traffic signal exploded following a leak in one of the gas lines below, severely injuring the policeman operating it. This led to the semaphore project being dropped in London.
America's evolves the signal system
In America, the semaphore system continued to be rolled out, with more and more motorists, carts and trucks travelling on the road. However, with more traffic officers found it was difficult to judge congestion.
Potsdamer Platz in Berlin, Germany, in 1925 with the traffic light tower in the centre. Hulton Archive
While some cities began installing traffic towers, allowing officers to have a higher view of the traffic, in Utah in 1912, policeman Lester Wire developed the first electric traffic light system with red and green lights.
Two years later, the first electric signal was installed in Cleveland. It was based on a design by James Hoge and allowed police and fire crew to control the signals in case of emergencies.
Four-way systems and modern day
In Detroit, William Potts – also a police officer – decided to do something about the increasing number of cars on the roads. He looked to adapt railroad signals to be used on streets and developed a system with red, amber and green lights. He made the first four-way three coloured traffic system, and it was installed on the Woodward and Michigan Avenues in Detroit in 1920. A year later there were 15 automatic light systems.
Over the next 10 years, many inventors came up with new ways to control traffic signals. Charles Adler Jr came up with a signal that detected a car's horn, while Henry A Haugh developed a detector that sensed the pressure of passing vehicles.
The first electric traffic lights to be installed in England were in Piccadilly Circus in 1926. Just over 60 years later traffic lights became the subject of an art installation near London's Canary Wharf.
'Traffic Light Tree' was created by French sculptor Pierre Vivant, who described its meaning: "The sculpture imitates the natural landscape of the adjacent London Plane Trees, while the changing pattern of the lights reveals and reflects the never-ending rhythm of the surrounding domestic, financial and commercial activities."
World's first traffic light
Everybody seems to think it's obvious traffic lights must have appeared after cars, but not so fast. In another "Tech before it's time" instance, it turns out the first working traffic light actually hit the road, so to speak, in 1868 outside the Houses of Parliament in London. It was gas lit, and operated manually by a policeman standing next to it. The trick is to realise there were many horses and carts on the roads then, which had exactly the same needs as motorised vehicles when it came to keeping what had become busy traffic moving.
The first traffic management system, to get technical, was in the form of three policemen standing by the road waving the carriages through. This was in 1722, again in London but this time on London Bridge.
Red means stop
Right from the start, the light for "stop" was red. There's a detailed history of the traffic light on Wikipedia.
Here's an example of an early version:
The first traffic light actually blew up
To the amusement of motorists everywhere since, the first traffic light actually exploded as a result of a gas leak and injured the police officer controlling it.
Why Traffic Signs Are Needed Today
With over 164,000 miles of highway and four million miles of public roads in the United States, traffic signs are a necessity in today’s world. Can you imagine a simple drive to the grocery store without traffic signals or signs? Depending on where you live, this may seem like it wouldn’t be so bad. But for those who live in densely populated areas, it would certainly have an effect.
When exactly did traffic signs come about, though? Believe it or not, they actually date back all the way to ancient Rome. It just took many years before standardization led to the signs we know today.
When Were Traffic Signs Invented?
Imagine riding on horseback to a new job in a new city with only mile markers leading the way. You are not entirely where you’re going, but you’re pretty sure you’re running late.
It may seem strange as an inhabitant of the modern world, but the first road signs were milestones, and they were used in ancient Rome. Let’s look at the progression of road signs, from this ancient civilization to the signs you know today. You’ll be amazed at the history behind them, and you may never look at one the same again.
1. Ancient Rome
In one form or another, traffic signs have been in use since the time of the Roman Empire. Roads can be traced back to the Bronze Age, but the Romans took the idea and ran with it. By building a system of roads, tunnels and bridges from Portugal to Constantinople, the Romans were able to move armies faster and bring in more people and goods. In other words, a strong road system helped Rome thrive.
The first road was the Via Appia, or the Appian Way, built in 312 B.C. Milestones were placed at regular intervals and often stated who was in charge of maintaining that portion of the road as well as the completed repairs. The Romans also erected mile markers at intersections specifying the distance to Rome. — so you might say the Romans made the first road sign.
In ancient Rome, people traveled by horseback, in carts pulled by oxen or by walking — there wasn’t yet a need for complex highway systems to accommodate heavy traffic or the everyday person rushing to work or to pick up the kids at school. That comes later.
2. Middle Ages
During the Middle Ages, which is the period describing Europe from the fall of Rome in 476 A.D. to the 14th century, Roman road systems were still in use. During this time, various sign types were placed at crossroads to direct or point people toward different towns. However, when Rome fell, the roads were no longer maintained, and transportation was becoming more difficult. But, the discovery of the New World soon helped Europe improve transportation systems.
Everyone, despite social status, began to leave their comfort zones and travel, either in a covered wagon, on horseback or by foot. However, transporting goods in wagon slowed down horses and made travel a slow process. It wasn’t until travel became faster, with the invention of the bicycle and the automobile, that a need for better road signs developed.
3. The 1800s and the First Traffic Signs
The 19th century was a time of many inventions and progress in industry and transportation. Soon, many travelers would no longer need to hop on the back of a horse to get across town. Instead, they could travel further and faster thanks to new modes of transportation, such as:
Have you ever thought of a wild invention you figured was too crazy even to try? Don’t feel discouraged. Instead, let history inspire you. It took hundreds of years for the bicycle to become a reality. Did you know that the idea for a bike began in 1418? It was a human-powered four-wheeled device designed by Italian engineer Giovanni Fontana.
Despite Fontana’s vision, it wasn’t until 1817 that German inventor Karl Von Drais introduced his hobby horse, or two-wheeled vehicle. The hobby horse was made of wood, including the wheels, and it did not have pedals. This meant the rider moved the vehicle by foot. As you might imagine, the popularity of the hobby horse did not last very long. Plus, this elementary bicycle was seen as a threat to pedestrians.
Nevertheless, bicycles returned with a fury in the 1860s. Wooden wheels were replaced with steel, and pedals were introduced. This vehicle was known as the velocipede and made for a super bumpy ride. It’s not clear who invented the velocipede, but Pierre Lallement, a French carriage maker, obtained a patent for the vehicle in 1866.
By the end of the 19th century, bicycles were being manufactured to meet the safety and comfort demands of riders. With more people on bikes, the need for signs for bike riders, pedestrians and other travelers grew. Cycling organizations and local authorities started posting signs to help warn cyclists of steep hills or other hazards.
Eventually, automobiles and railroads overshadowed the convenience of bicycles, and they largely became children’s toys until a reemergence in the 1960s. Now, it’s estimated that two billion bicycles are being used around the world.
It’s hard to pinpoint who is responsible for the invention of cars. Like bicycles, automobiles came into vision hundreds of years before they became a real object for use. For example, Leonardo da Vinci was creating designs for the automobile all the way back in 15th century.
Although up for debate, Karl Friedrich Benz is credited with inventing the first gasoline-powered automobile sometime in 1885 or 1886. It was in 1893 that brothers Charles Edgar Duryea and Frank Duryea established the first automobile manufacturing company in the United States.
No matter what, though, the rise of the automobile meant signs were even more of a necessity.
One of the earliest organized signing systems was developed by the Italian Touring Club in or about 1895. By the early 1900s in Paris, the Congress of International Touring Organizations began considering standards for road signage. In 1909, nine European governments chose four pictorial symbol signs to be used as a standard in those areas.
In the United States, the 1900s also came with a call for signs to meet automobile industry growth. Drivers were easily getting lost without signs. The signs that did exist at the time were often damaged or broken. As a result, Americans were becoming aware of a need for signs.
As early as 1899, the beginning group of the American Automobile Association was formed, partially to place signs on busy roads and help guide travelers to their destination. In 1905, the Buffalo Automobile Club installed a signed network in New York State, and the Automotive Club of California soon followed by placing signs on the most important highways around San Francisco. Sometimes colored bands were wrapped around utility poles as signs.
Although most middle-class families couldn’t afford cars until the 1920s when cars were being manufactured more efficiently on assembly lines, signs were still in demand by wealthy car owners. Signs were becoming so important, that auto clubs actually competed to be in charge of adding them to popular routes — so much so that there’d be multiple signs in one area. Talk about confusing!
What Did Early Traffic Signs Look Like?
Early signs, like those made by the American Automobile Association, were composed of wood and placed on iron columns. Many old signs were eventually used to supply metal for World War II. In 1915, Detroit installed the first stop sign, which was a two-by-two-foot sheet of metal, with black lettering on a white background.
At this point in history, the signs were not reflective and did not have any standardization between various government agencies. Vehicles operated at low speeds, and drivers were expected to watch out for other vehicles and obstacles for themselves.
When automobile traffic began to increase in the 1920s, however, people were traveling on roads they were not familiar with, and they were not being warned about potential hazards. It was time for a uniform look.
What Is the History of Traffic Sign Standardization?
With people getting lost, auto clubs fighting over who gets to place a sign and complete traffic chaos, an urgent need for standard signs arose. Next time you notice a stop sign or construction sign, you’ll feel grateful it’s there. Travelers in the early days probably spent more time getting lost than enjoying the trip.
Standardization began in 1922 when W. F. Rosenwald of Minnesota, J. T. Donaghey of Wisconsin and A. H. Hinkle of Indiana traveled through several states trying to come up with some standardization or uniformity to mark and sign roadways. They reported their findings at the 1923 annual meeting of the Mississippi Valley Association of State Highway Departments (MVASHD). After some debate, the organization agreed on some distinct shapes to be used for various situations. The shapes were as follows:
- Round: Railroad crossing warning
- Octagon: To stop
- Diamond: To show that precautions need to the be taken in a specific area
- Square: To show some care needs to be taken occasionally
- Rectangular: For directional or regulation information
- Star-Shaped: A unique shape used to mark highways
All signs were to have white backgrounds with black letters or symbols. Instead of being hand-painted as in the past, the border and the lettering or symbols would be embossed — or pushed into the metal. The sign was dipped into paint, and the lettering, symbol and border were painted black. This process allowed signs to be made in larger quantities. The machinery, however, could only make signs a size of 24 inches, so the MVASHD used this as their standard sized sign.
Shortly after the MVASHD meeting, the state of Minnesota published a Manual of Markers and Signs. This is what many consider to be the first manual for traffic signs. Soon, other publications were created to meet the needs of motorists, and important changes were taking place. As you’ll see below, road signs were being taken a lot more seriously than the good old days. Here’s a timeline of traffic sign publications to demonstrate the progress from mile-markers to sign requirements:
- Between 1923 and 1927: Both the American Association of State Highway and Transportation Officials (AASHTO) and the National Conference on Street and Highway Safety (NCSHS) published manuals for standard signs and traffic control devices.
- In 1924: At their annual meeting, the AASHTO recommended that all warning signs be black on yellow background. They also created a Joint Board on Interstate Highways to create numbering systems for roadways.
- In 1925: The Secretary of Agriculture accepted the Joint Board’s recommendations which led to the first publication of the National Signing Manual. This manual was for rural highways only.
- In 1929: The second edition was published and contained information on the use of reflecting elements and of luminous elements mounted below a standard sign or on a separate post.
- In 1930: The NCSHS adopted the Manual on Street Traffic Signs, Signals and Markings. This manual was for urban areas. Some of the differences between the urban and rural manuals were colors for some signs, size of the signs and the difference between railroad signs.
- In 1935: The first edition of the Manual on Uniform Traffic Control Devices (MUTCD) was published. This helped to resolve some of the differences between the rural and urban manuals. The signs in this manual were classified as regulatory, warning or guide signs. All signs still used block lettering, which had been standard for many years. This edition also recommended that certain signs, such as stop signs, be illuminated at night. The illumination could be accomplished by the use of glass spheres or “cats eyes” placed around the border or by using floodlights for the signs. The minimum size for signs in this manual was 24 inches and increased in size in six-inch increments. Only 40 signs were illustrated in this addition.
- In 1939: The MUTCD was revised. The highlights of this revision focused on sign illumination. Illumination for route markers, destination and one-way signs was also recommended but not required. White reflectors were used for all signs except for stop signs which could use red reflectors.
- In 1942: A war edition of the MUTCD was published. This edition addressed blackout conditions, the conservation of materials and the need to limit placement to locations for public safety and the efficient movement of essential traffic. Because metal and chromium were needed for the war effort, signs made of wood and composite material became more common.
Blackout conditions created many problems and difficulties for vehicle operators. Only vehicles equipped with approved blackout lights could move during such blackout conditions. An approved vehicle could only have one headlight with very low candlepower and would only illuminate the roadway between 20 and 100 feet ahead of the vehicle. This made seeing traffic signs mounted at normal heights nearly impossible to see. This wartime edition required blackout signs to be mounted no more than 24 inches above the crown of the road, and only the message could be reflected. The blackout sign would be placed on the same post, just at ground level. This edition mainly addressed the difficulties relating to traffic control devices created by war.
- In 1948: After World War II, a new MUTCD edition was published. This edition had some important changes relating to traffic signage. Some of these changes included the adoption of the round letter alphabet, and sign legends were simplified by eliminating unnecessary words. Illumination was required for all warning and regulatory signs, and sign sizes were emphasized.
- In 1954: In this revised edition of the MUTCD, a couple of significant sign changes were made. The most notable was the change in the color of the stop sign. The color changed from black on yellow to white on red. This edition also prohibited the use of secondary messages on stop signs. The yield sign was introduced in this edition as well. The sign was a yellow triangle with the black wording “Yield Right of Way.”
- In 1961: This edition of the MUTCD brought additional changes to traffic signs. This edition recognized the desirability of using symbols. Sign sizes were also increased in this edition, and the yield sign was shortened by deleting the words “Right of Way.” This edition also addressed the need for traffic control devices for highway construction projects for improved safety. Construction warning signs were specified to be black on yellow.
- In 1971: The MUTCD expanded the use of symbols on signs increasing international uniformity. The public was educated of these changes by educational plaques below the signs. This edition also allowed the color red to be used for several additional regulatory signs. The colors white on green were made the standard color for guide signs. The color orange was introduced for construction signs and work zone devices. This is also the first time school areas were addressed, and the pentagon-shaped school sign was introduced.
- In 1978: The MUTCD added several new symbols for signs, as an alternative to words. Symbols for flaggers and workers were added to the construction sign section.
- In 1988: The MUTCD added a new sign section on recreational and cultural interest signs.
- In 1992: The U.S. Department of Transportation (DOT) and Related Agencies Appropriations Act enacted legislation requiring the MUTCD to include a minimum level of retro-reflectivity. This new standard had to be maintained for all signs that applied to roads open to public travel.
Although the manual is always being revised to improve the safety and efficiency of travel, one thing stays the same — it appreciates order!
Now, you can expect the following road sign colors for instant communication, as color indicates the message contained. Here are present-day sign color meanings:
- Red: Used to stop, yield and prohibition
- White background: regulatory sign
- Yellow: general warning message
- Green: permitted traffic movement and directional guidance
- Fluorescent yellow or green: School or pedestrian crossings
- Orange: Warnings and guidance in construction zones
- Blue: Road service, tourist information or evacuation routes
- Brown: Guidance to recreational or cultural interest sites
The United States is not the only place to need a constant revision of road sign standards. Another example is Britain.
In Britain, before the 1950s, road signs were a disaster. It took graphic designers Jock Kinneir and Margaret Calvert to create standard and easy-to-read road signs. After testing different versions, they created new signs based on the European standard that triangular signs warn, circles command and rectangles provide information. They used drawings or pictograms more than words.
A picture can convey a message a lot quicker than words sometimes, and that’s exactly what British drivers needed.
When Were Animal Signs Invented?
You know those road signs that warn of deer crossing? Well, they are there for a good reason. Deer exist all over the United States, and an accident with a deer can lead to some serious damage.
Deer are the leading animals in car and animal collisions — with about one million deer/vehicle collisions happening annually.
It wasn’t until the 1950s that deer warning signs were taken seriously, though. Nevada was the first state to include a deer warning sign in their driver manual in 1953. However, by the 1990s, 24 states included deer warning signs in their driver manuals.
Now, many of us recognize the yellow and black deer sign. The sign helps alert drivers to areas with a heavy deer population. Depending on where you are, you could also see warning signs for turtles, moose or ducks.
Where Was the First Traffic Light?
In addition to road signs, traffic lights are an integral part of the traffic system.
The first traffic signal was designed by a railroad signal engineer, J.P. Knight and was installed outside the houses of the British Parliament in 1868. It had semaphore arms like any railroad signal at the time and red-green lamps fueled by gas — but after it exploded and killed a police officer, further development was discouraged.
That means the first permanent traffic control light wasn’t installed until 1914 in Cleveland, OH. Using the look of railroad signals, the first traffic control light was also red and green, and it was used to control traffic. New Yorkers were already experiencing traffic jams twice a day as early as 1913, so traffic control came at a good time.
Unlike the lights we know today, early traffic lights faced only two directions, and police officers controlled traffic on side streets. Other officers manually controlled the light from a booth on the corner. Officers were also needed to make sure drivers actually obeyed the rules of the light.
In 1917, a Detroit police officer named William Potts added the yellow light to caution drivers and pedestrians between changes.
By 1918, Chicago and New York had these manually-operated lights, and soon many American cities followed. In 1922, automatic signals were available which allowed many police officers to take care of other matters. By 1926, New York had 98 automatic lights.
How Are Traffic Signs Manufactured?
Did you know many road signs are designed to break in two in case of a car crash? It’s true. Many road sign posts use a slip base, which helps the pole snap in two to help keep drivers safe and prevent vehicle damage in an accident. Put simply, the post is attached to the base with bolts that loosen on impact. The base remains in the ground allowing a car to drive over it while the sign and the post disconnect.
Although not all road signs are installed with a slip base, you can expect most road signs to be made using the following process. First, traffic signs are no longer made of stone, like in the Roman days, or of cast iron or unfinished wood like early traffic signs. Now, signs are designed for durability and practicality. In general, traffic signs are composed of one of the following materials:
Manufacturing traffic signs requires several steps to ensure a sign is sturdy and legible. To manufacture a sign, a worker will:
- Cut the blank: The sign blank is cut, and the corners are rounded. Holes are punched for mounting the sign.
- Check: The blank is checked for dirt and defects before the next step is taken. Blanks must be free of any debris for the reflective sheeting to adhere properly.
- Degrease: The blank is wiped clean with a special solution to remove any fingerprints or grease.
- Apply reflective sheet: A reflective sheet is cut and applied to the blank surface.
- Heat: The sign is heated before copy or symbols are applied, and then it is left to cool.
- Apply reflective letters: Letters, symbols and borders are applied in black or white reflective sheeting. The sign is heated again.
Different types of reflective sheeting produce different results, which also need to be considered. For example, microprismatic sheeting produces high-intensity reflection and is typically applied to highway signs and construction zone devices. All signs must be maintained and regularly inspected or replaced to meet retroreflective standards. We’ll go into more detail about retroreflection soon.
It’s important to manufacture a sign that adheres to standards set by the MUTCD.
What Are Traffic Sign Requirements?
When you’re driving at night, you probably know the importance of being able to see traffic signs. Reflective signs are very important to safe navigation. Did you ever wonder how you can see traffic signs at night without electricity? The science of retroreflection makes easy nighttime travel a reality. Most signs are required to be retroreflective. Considering the nighttime crash rate is almost three times the daytime crash rate, it’s probably good that this requirement exists.
According to the DOT, a few signs are exempt from retroreflection maintenance. These include:
- Parking signs
- Walking or hitchhiking signs
- Adopt-A-Highway signs
- Brown or blue backgrounds
- Exclusive use of bikes or mopeds signsF
However, these signs must still meet other MUTCD requirements and must be created to be retroreflective. All other signs must be regularly inspected and maintained to meet retroreflective requirements.
What Is Retroreflection?
Signs retro-reflect a car’s headlights, which means the sign reflects the light back to the vehicle. Signs are composed of special plastics that contain millions of small prismatic beads. This makes it possible to catch the light reflecting off a sign at just the right angles.
Reflective sheeting dates back to the 1930s, and we still use similar technology today. However, in the 1980s, signs started to be manufactured with tiny prisms rather than glass beads. Other design requirements stated by the MUTCD include:
- Dimension: The overall dimensions of sign plates should be in multiples of six inches when applicable. Sometimes signs need to be bigger or smaller than the standard size depending on the situation. When signs must be different than the standard size, lettering needs to be adjusted and either reduced or enlarged to meet standards.
- Letter style: Letter types need to be the ones shown in the Standard Alphabets for Highway Signs book. It has been proven that wider spaces between letters improve legibility. Letters are usually uppercase.
- Letter size: Typically, letters should be at least six inches in height. A rule to remember is to have one-inch of letter height for every 40 feet of desired legibility.
- Amount of legend: Road signs should be limited to three lines of principal legend including place names, route numbers and street numbers to increase instant legibility. In other words, signs cannot feature too much information.
- Borders: With some exceptions, all signs are to have a border with the same color as the legend.
Those are just a few of the rules — but we’ve come a long way from mile-markers to the modern road sign.
What Is the Future of Traffic Signs and Manufacturing?
The need for new traffic signs is always growing and changing, especially to keep up with advancements in technology and modern lifestyles. In some places, signs are going digital. Have you noticed weather or traffic advisory signs along the highway? If you live in Iowa, you may have also experienced some digital roadside humor.
The priority of an effective traffic sign is to be attention-grabbing and legible. Next, a sign needs to be able to communicate a message instantly. When it comes to road signs, simple is best.
Some states are making use of embedded light emitting diodes (LED) to enhance visibility. The DOT says LEDs improve safety at intersections because they enhance awareness. These lights are solar-powered, may be set to flash or stay on and can either be used all day or set to activate when drivers or pedestrians approach. LEDs are especially effective for stop signs and problem areas.
As technology advances, expect traffic signs to remain visually simple but more legible at night and from further distances. The point of traffic signs is not to distract drivers, but to communicate a message as quickly as possible at any hour of the day. Signs will continue to be manufactured with a high priority on legibility and standards.
Are You Looking for an Experienced Sign Manufacturing Company?
Over all these years, U.S. road signs have seen significant improvement. In the beginning, there was few, and they were far between. Today, it is almost impossible to go onto any road without seeing a road sign directing drivers and pedestrians where to go.
D.E. Gemmill is a proud PA and MD approved sign manufacturing facility, and our signs adhere to the highest standards to ensure material compliance and to meet current retroreflective standards.
If you are looking for an experienced sign manufacturing company or help with road sign installation, we encourage you to contact us today for all your ADA, custom interior or exterior signage, wayfinding signage, banners and road or highway signage needs.
The First Traffic Lights
The very first traffic lights were introduced outside the Houses of Parliament in London in 1868. British railroad engineer, John Peake Knight, modified a signalling system from the railway for use on city streets to control the traffic of horse carriages and allow passengers to cross the road safely. He utilised an adapted version of semaphore arms to signal during the day and red and green coloured gas lights at night.
While initially, the system helped to improve traffic flow and improve safety for pedestrians, using gas lights proved too risky. On the night of the 2nd January 1869, the gaslight exploded and killed the policeman who was operating the lighting signal.
9th December 1868 – The First Traffic Lights
In the 1860s London was the largest city in the world, with 3 million people squeezed into an area much, much smaller than the present-day city. This high population density caused many problems. These ranged from epidemics of infectious diseases, to pollution from the six million tons of coal that were burned each year, and squalid and overcrowded slum housing.
One of the most obviously visible problems was traffic. The motor car had yet to make an appearance, but the streets were filled with hundreds of thousands of horse-drawn carts, carriages and buses. Traffic jams were a constant problem and were at their worst around the bridges that crossed the River Thames, which created bottlenecks. The lack of control over the traffic made it dangerous as well. Over 1000 people were killed and more the 1300 injured on London’s roads in 1866.
A year earlier, in 1865, a 36 year-old engineer, John Peake Knight, had contacted the Metropolitan Police with an idea. He was Superintendent of the South Eastern Railway and thought it should be possible to use signals, like those used on the railways, to control and improve the flow of traffic.
John Peake Knight – looking suitably noble.
As ever the idea took a while to be developed but by the end of 1868 a prototype system was ready. It was installed on the north side of Westminster Bridge, close to the Houses of Parliament and Big Ben. The system used railway style semaphore arms to indicate when traffic should stop and when it could go. At night the arms were replaced with gas powered lights. The lights also followed the colour coding system used on railways, red for stop and green for go. These were the first traffic lights anywhere in the world.
Because it was a totally new concept for road users, posters were put up near the signals explaining how the system worked. There was no way of automating the system, so a policeman had to stand next to the signals to operate them – not a great job in the depths of winter. The signals went into operation on 9 th December 1868.
The system caused an immediate improvement in traffic flow, and John Knight was confident that more sets of signals would be installed in other London traffic hot spots. Then disaster struck. In early January 1869 the gas supply developed a leak and one of the lights exploded, leaving the policeman operating them with a badly burned face. At this point the system was considered too dangerous for further development and whole project came to sudden and disappointing end.
It would be nearly sixty years before the next traffic lights were installed in London. In 1925 a set using safer electric lamps went into use near Piccadilly. As anyone who drives in London can testify, quite a few more sets have followed since.
When was the first traffic light installed? Today in 1914.
It's the 101st anniversary of the first electric traffic signal system. On August 5, 1914, in Cleveland, Ohio, engineers installed a pair of green and red lights facing each side of a four-way intersection — a simple experiment that has since shaped roads around the world, and is honored today in a Google Doodle.
In a technical sense, Cleveland's device might not seem all that impressive. It was actually preceded by similar temporary systems in London and Utah, and like the others, it was manually operated. Its chief benefit was allowing a policeman to sit in a booth next to the intersection instead of standing dangerously within it.
But this simple invention marks a key moment in the largely forgotten transformation of roads during the 20th century. For most of history, roads have been chaotic, shared public spaces, packed with horses, handcarts, merchants, pedestrians, and children. As much as any other invention, the traffic signal gave rise to the carefully controlled, highly automated thoroughfares we think of as roads today.
Why we needed traffic signals
Horses, carriages, carts, streetcars, and pedestrians had been navigating busy intersections for years — but they moved pretty slowly, which meant turn-taking and other informal driving customs generally worked fine.
San Francisco's Market Street, in 1906, shows a handful of automobiles mixing informally with streetcars and carriages.
As automobiles began to appear in US cities in the 1900s, there was no system for dealing with their speed. Sharing the streets with pedestrians and driving unpredictably, they caused alarming numbers of deaths and crashes. As historian Peter Norton writes in Fighting Traffic, this led the public to generally vilify the car — and prompted police departments to get involved in the business of traffic regulation.
In many cities, they first did so based on a set of driving rules created by New York businessman William Phelps Eno in 1903. Among other ideas, he suggested traffic circles, one-way streets, pedestrian crosswalks — and for drivers making a left through an intersection, the requirement to turn at a hard right angle.
Eno's rules prohibited soft left turns (left), requiring drivers to stay in their lane until turning at a hard angle (right).
It might seem minor, but this hard left turns rule was a key way to ensure that cars didn't smash into each other — and crossing pedestrians — at intersections. With drivers making these kinds of turns, traffic at intersections could flow smoothly for the first time.
At first, police enforced this rule by whistling at cars that cut corners, but in 1904, Eno proposed the idea of building a post in the center of each intersection (marked "C" in the diagram above) with a sign that said "keep right." New York installed many of these posts — eventually termed "silent policemen" — and other cities around the US followed. They were the first real infrastructure aimed at controlling cars — and, as Norton writes, "This humble traffic device marked the victory of common-sense traffic reform where custom alone had proved inadequate."
A sketch of an early traffic semaphore.
At busier intersections, these silent policemen were paired with actual policemen who gave hand signals indicating which lanes had the right of way. Eventually, some cities used devices called semaphores mounted on the center poles. Modeled after railway signals, they could be cranked or turned to show some drivers the word "STOP" and others "GO."
But as more and more cars arrived on the roads, standing at the center of a busy intersection became increasingly dangerous. It also gave police a poor view, leading long lines of traffic to form — sometimes trapping fire trucks and ambulances.
How the new traffic signal worked
An officer operated the signal from a booth next to the intersection.
The system installed in Cleveland wasn't the first we'd recognize as a traffic signal today. London's 1868 signal used semaphore arms combined with red and green gaslights during nighttime — colors that had long been used to mean "stop" and "go" by various sorts of industrial machinery. It exploded after about a month of use, though, injuring the operator.
Then, in 1912, police officer Lester Wire built and installed a device in Salt Lake City that "looked like a large birdhouse with lights dipped in green and red paint and placed into circular holes on each side," according to the Salt Lake Tribune — but it, too, was short-lived, and Wire seems to have gone off to World War I instead of securing a patent.
Finally, in 1914, at the corner of Euclid Avenue and East 105th Street — one of the busiest intersections in Cleveland — the city hired the American Traffic Signal Company to implement an enduring system that had been patented by Clevelander James Hoge a year earlier.
Hoge's original 1913 patent submission, which used lights with words printed on them (not included in the Cleveland system).
Its design was simple: An operator in a booth flipped a switch to illuminate either a red or green light on wires suspended above each side of the intersection. As Cleveland director of public safety Alfred A. Benesch wrote in 1915, "[It] takes the traffic officer out of the center of the street and places him at a corner of the sidewalk and at an elevation from which he can see over the heads of the crowd." If a fire engine arrived, he could throw an emergency switch, which would illuminate all red lights and allow him to clear out the intersection so it could pass.
Benesch deemed the experiment, which cost $1,500 to install, a complete success. Other cities attempted to solve the same problem with traffic towers — elevated booths that policemen could sit in at the center of the intersection — but over the next decade, remote-operated, lighted systems like Cleveland's gradually won out.
In 1920, Detroit policeman William Potts introduced the yellow light soon after, cities such as New York and Philadelphia began introducing lights with linked circuits, allowing many intersections to change at the same moment. Eventually, the lighted traffic signal became the standard control mechanism for busy urban intersections.
How the traffic signal gave rise to the automobile age
The American history of roads, more than anything, is the story of informal public spaces being transformed into tightly regulated conduits for traffic. In most places across the country, for better or worse, roads have been taken away from pedestrians and other non-drivers to allow cars to move as quickly as possible.
The intersection of La Salle and Monroe Streets in downtown Chicago, 1912 vs. today. (University of Minnesota/Google Street View)
A huge range of inventions and policies — from the concept of jaywalking to the controlled-access highway — were crucial in this transformation. But the traffic signal came at a particularly pivotal time.
During the 1910s, when electric traffic lights first popped up, cars were still a plaything for the rich. When drivers ran over pedestrians, they were publicly portrayed as murderers. For a brief moment, many felt that automobiles were inherently deadly machines, with no place on city streets.
If police departments, engineers, and auto enthusiasts hadn't figured out a way to minimize the carnage, that might never have changed. But they managed to do so, by forcing pedestrians to use crosswalks, writing rules to standardize the flow of traffic, and, crucially, regulating activity at intersections, where a disproportionate amount of accidents occurred.
During the 1920s, cars steadily began to filter down to the middle class, eventually becoming mainstream — and traffic signals became commonplace in most large American cities.
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Who was J.P Knight?
John Peake Knight was born on December 13, 1828, in Nottingham.
He left Nottingham High School aged 12 and worked in the parcel room at Derby railway station.
Knight enjoyed a successful career in UK railways and aged 20 was promoted to Traffic Manager of the London to Brighton line.
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He is credited with improving the quality of rail travel in Britain - installing safe carriages and alarm pulls for women.
Knight and his wife Elizabeth had five sons.
The inventor died in 1886 and was buried in London's Brompton Cemetery.
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The world's first traffic light was installed in London 150 years ago – but it soon claimed its first casualty
hey’ve saved millions of motorists’ lives but very first traffic light installed in London 150 years ago tomorrow actually led to a disaster.
The humble but ubiquitous road safety system was first unveiled at the junction of Great George Street and Bridge Street in Westminster on December 9, 1868, after Nottingham engineer John Peake Knight decided to bring the railway signalling system onto roads.
It was a fairly simple set up - the signal used red and green gas-powered lamps under the manual control of a policeman.
However, the trial only lasted a month because a gas main leak resulted in one of the lights exploding and seriously burning the policeman on duty.
There are even some reports the unfortunate bobby may have been killed, and the UK’s roads remained traffic light-free until deep into the next century.
As the 150th anniversary approaches, Edmund King, president of British motoring association AA, said: “It didn’t come back to Britain until about 1925.”
During its absence from the UK, the technology was developed further in the US and then around 1929 the first electric signals started becoming commonplace in London.
Despite the traffic light’s long history, its greatest period of growth did not happen until the 2000s.
According to the AA, between 2000 and 2008 there was a 30 per cent increase in traffic lights across the UK and 25 per cent in London, bringing an extra 6,000 traffic lights.
“In the ‘80s and the ‘90s, the increase in traffic lights was probably then in central urban areas, to help pedestrians, to help cyclists,” Mr King continued.
“Now, it’s more at these big junctions that tend to be at the periphery of urban areas where you might have a big roundabout-type junction but now regulating it with traffic lights, and you are seeing an increase in that.
“So, after 150 years, the Great British traffic light is far from dead, it’s increasing on quite a scale.”
Countdown systems that provide pedestrians with a timer and traffic lights for cyclists are among the more recent trends, but questions have been raised about the future of the traffic light as technology around autonomous vehicles continues to develop.
“That will take a very long time because with driverless cars the lines on the road are absolutely crucial, the cars have to read the lines on the road,” Mr King said.
“Until all cars are driverless, you will still need the wonderful British invention of the traffic light.”
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