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Standardizing Traffic Control Devices

One hundred years ago, many rural highways were established and maintained in the United States and Canada by automobile clubs. Each such roadway had its own signage, the chief purpose of which was to promote the roadway. Assisting with way finding and safety were the main objectives. Disputes between clubs sometimes meant that some roadways had multiple sets of signs. 

By the early 1920s, “groups from Indiana, Minnesota, and Wisconsin began surveying the existing road signs in order to develop a standard. They reported their findings to the Mississippi Valley Association of Highway Departments, which adopted the report’s suggestions for the shapes to be used for road signs. These suggestions included the familiar circular railroad crossing sign and octagonal stop sign.” (source:  “Wikipedia encyclopedia”)
Over the years, government stepped in. Standardization increased together with the increase in highways and motor vehicle traffic.
By 1932, the American Association of State Highway Officials began working
with the National Conference on Street and Highway Safety to develop a uniform standard for traffic control devices. This effort produced the Manual on Uniform Traffic Control Devices, the MUTCD. First released in 1935, the MUTCD set standards for both road signs and pavement markings. New editions of the MUTCD include changes that have followed from upgrades to the nation’s road systems and new technologies.
Canada has its own Manual of Uniform Traffic Control Devicespublished bythe Transportation Association of Canada [TAC]. The Canadian MUTCD is similar to the US MUTCD but with key differences most notably the inclusion of English/French signage, and a heavier reliance on symbols. Since 2000, this manual has been divided into a series of smaller volumes each covering different aspects of traffic control such as regulatory signs, traffic signals, etc.
When new traffic control devices are developed, studies are undertaken by various government agencies to evaluate their effectiveness. A recent example is the pedestrian countdown signal, which has yet to gain universal acceptance.
This device has its proponents, but there are also traffic engineers who take the view that it is not significantly better than existing pedestrian signals. It consists of the standard pedestrian signal with the addition of a panel to display the countdown (in seconds) of the remaining crossing time.
The countdown timer starts either at the start of the WALK phase (the white walker) or at the start of the FLASHING DON’T WALK[FDW]phase(the red flashing hand). At the end of the FDW phase, also called the pedestrian clearance interval, the countdown timer displays a zero and the DON’T WALK solid red hand is displayed. At this point the pedestrian crossing should be cleared of all pedestrian traffic. A slight interval then follows before the traffic signal changes to green to permit vehicular traffic to proceed across the walkway.
Some cities now use the pedestrian countdown signal, and some are resisting it. Will it become standard? If it is a safer system, then why not?

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