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Posted by on Dec 16, 2017 in Tell Me Why |

When Were Fixed-time Traffic Lights Invented?

When Were Fixed-time Traffic Lights Invented?

Fixed-time traffic lights were invented in the United States and introduced in New York in 1918. Eight years later the United States set up a committee on Uniform Traffic Control. The purpose of traffic lights is to control the flow of traffic, determine the right of way at intersections and give greater safety to drivers. By linking successive traffic signals together a progressive movement through the streets can be provided.

Traffic lights were used for the first time in Britain at Wolverhampton, Staffordshire, in 1928. Sixty years earlier the London police had introduced a system of traffic control signals based on the swinging arms of the semaphore.

fixed-time signals

In general, fixed-time signals are the rule in urban areas for reasons of regularity, network organization, predictability, and reducing unnecessary delay. In certain, less-trafficked areas, actuated signals (push buttons, loop detectors) may be appropriate; however, these must be programmed to minimize delay, which will increase compliance.

Actuated signals in general are not preferable because of the maintenance requirements and upkeep of the detection on the street. Fixed-time signals incur lower initial and ongoing maintenance costs than actuated signals.

Drivers and others at downstream unsignalized intersections benefit from a series of fixed-time signals, as they produce routine gaps in traffic that may be used to turn onto or cross the street. Fixed-time signals help make pedestrians an equal part of the traffic signal system by providing them with regular and consistent intervals at which to cross.

Content for this question contributed by Richard Crawford, resident of Milliken, Weld County, Colorado, USA