Traffic Lights and Traffic Light Signal Co-ordination


Traffic lights are an essential prerequisite for the safe and efficient management of trucks, cars, motorcycles, bikes and pedestrians on our country’s roads. In order to realise optimal operational efficiency, traffic light systems need to be constructed, managed and signalling patterns set up in order to cope with constantly changing patterns of traffic. That is why traffic engineering managers collect and aggregate a lot of detailed data relative to: traffic volumes traffic flow and relative speeds traffic patterns



After this information has been processed, engineers formulate new timing sequences for particular road junctions and fine adjustments are made at the roadside during actual traffic conditions. In order to maximise the flow of traffic along arterial roads, signals are interconnected and often closely spaced together in order to create integrated and coordinated traffic light signalling systems.


Coordinated traffic light signalling systems are of great benefit to road users because they: Improve road safety Reduce atmospheric pollution through more efficient fuel usage The main determinant of whether, where and how traffic light signalling systems are deployed is often a function of historical accident and traffic statistics. When properly installed and configured, traffic light systems solve problematical issues like controlling and heavy traffic flows on major thoroughfares in order to allow traffic from adjacent roads to enter of cross the main road. If traffic light systems are properly programmed, they can manage the traffic flow at a particular road junction or intersection and optimise the flow of traffic in all directions thus reducing congestion. Under most normal operating conditions, this will reduce accidental collisions.


However, traffic lights are not a panacea for all traffic issues because driver error or prevailing natural light conditions may lead to an increased prevalence of “rear end” collisions when traffic lights have been erected. This may occur immediately after previous control measures like “stop-signs” have been removed. Traffic engineering specialists follow predetermined criteria to establish whether a traffic signalling system is required at a particular junction. Traffic signalling systems will only facilitate improved and safer traffic flow when deployed properly when the situation is appropriate. You have to realise that road users have to change their behaviour causing vehicle to stop where they may not have been required to stop in the past.


So, if lights for traffic control are deployed at road junctions where their use is inappropriate, road users can become frustrated and use alternative routes which in turn can create new traffic management issues that road safety managers will need to address! That’s because the deployment of new traffic lights almost always leads to the creation of real or simply perceived delay in a driver’s mind.



This in turn may see them using side roads which can further increase delays especially in “rush hour” periods. In extreme circumstances frustrated drivers may begin to break the law. That’s why deployment of new traffic control measures must be perceived as “reasonable” by many different types of road users.


So traffic light signalling systems only make vehicle traffic flow more smoothly and safely when used in apprppriate circumstances. Traffic lights cause vehicles to stop where they may not have had to stop previously. When they are used at a road junction where their use is not justified, traffic lights can make drivers frustrated. As stated earlier, there is an increased prevalence of “rear end” collisions when traffic lights are installed. But traffic safety managers have come to accept a slightly increased incidence of these types of minor collisions because there is normally a greater reduction in more serious broadside or angular collisions.