TRAFFIC LIGHTS (Safe Drive Training)

In Rio de Janeiro, motorists are now officially allowed to run red lights, so long as they can prove to police that they were escaping armed bandits.

Each year in Queensland there are an estimated 3000 crashes at intersections controlled by traffic lights.

A large proportion of these crashes are because someone has tried to run a red light. Crashes that occur when a driver attempts to run a red light are usually very severe due to;

1. The high impact speed, as the car running the red light is usually travelling at 60-80 km/hr and has little time or room to brake. In many crashes the at-fault driver does not apply the brakes before impact has occurred.

2. The impact angle is such that the red light runner strikes or is struck on the side where there is minimal crash protection.

Before the introduction of Red Light Cameras, crashes from red light runners seriously injured or killed more than 1000 people in Queensland every year.

Red Light Cameras operate automatically day or night. A Red Light Camera is connected to traffic lights and is activated when a vehicle crosses the stop line after the lights have turned red. (The camera will not be triggered by vehicles crossing the stop line on orange or green lights)

Once triggered the Red Light Camera takes 2 photographs (one second apart) of the offending vehicle. Details are recorded on each photograph of the time, date, lane position and the number of seconds since the light turned red.

The 2 photographs provide proof as to whether the vehicle continued into the intersection and committed an offence or stopped in the intersection.

Any vehicles already in the intersection when the traffic lights change do not activate the camera.

In Sydney, Newcastle, Wollongong, Gosford, Melbourne, Adelaide, Perth, Hobart, Darwin and Canberra the majority of the traffic lights in each city form part of the most advanced urban traffic control system in the world.

Developed by the NSW Roads and Traffic Authority (RTA), SCATS is an adaptive system of controlling traffic lights to optimise the flow.

For example the system automatically adapts itself to the moment to moment demands of the ever changing traffic flows within each area. The system can help then to clear sudden traffic loads from sporting or concert events.

Sensors under the road (seen as cuts in the pavement before the stop line) monitor the presence and density of passing traffic. Based on this information the microcomputer traffic signal controllers adjust the signal timing to suit the traffic flow. The flow data (and other information) is also relayed to the regional computer via telephone lines.

In Sydney there are 28 regional computers which can each monitor up to 128 intersections in there area.

Each regional computer processes the data received from each intersection and relays back messages to each local traffic light controller on the optimum times to change light phases.

This optimisation results in improved throughput and reduced delays. The aim being to link series of signals to form "green waves".

The central computer is housed in downtown Sydney and monitors the operation of each regional computer.

Specially trained operators monitor the operation of the system and make changes as required. The control centre has a bank of 64 television screens which display images from TV cameras installed throughout the city. Each operator can move and zoom the TV cameras to find the cause of delays such as broken down vehicles or crashes.

Traffic signals can be changed manually from the control centre to allow priority for emergency vehicles.

SCATS will reduce your journey time and improve fuel consumption compared to driving in regions with uncoordinated or fixed time traffic signals.

If the driver adopts the following driving tips they can be assured of progressing through more successive green signals;

Unless there are good reasons for doing otherwise, when arriving a traffic lights select the lane with the shortest queue (this helps to bunch traffic).SCATS is designed to coordinate traffic travelling at or below the speed limit. Stay with the main bunch of traffic and do not accelerate ahead of the group (you will only arrive first at the next red light)If the signal changes to orange, stop if it is safe to do so. Running the orange light deliberately is dangerous and you will most likely be stopped by the next signals anyway.If the signals ahead are red, do not race up to them; slow early and drift to the end of the queue (this greatly improves fuel economy and reduces frustration)Stop just before the solid white line at the intersection. If you stop to far past the sensor it may think you went through the lights as they were changing. If you stop more than 5 metres behind the solid white line, chances are you haven't triggered the sensor pad. Either way the traffic lights won't register your presence and change.When entering an intersection from a minor road or when making a right turn at the intersection do not allow an unnecessarily large gap from the vehicle ahead, as the sensor may mistake the gap as the end of the traffic stream and end the green light prematurely.
After entering a main road from a side street you will often get a red signal at the next intersection. However from then on you will be part of the next green wave.

With this in mind, no system is perfect and the computers are working in everyone's best interest to minimise traffic congestion. If the traffic lights you are waiting at seem to show green for a very short period (allowing only a few cars at a time to cross the intersection) there is probably a good reason for it; like a crash or traffic delay ahead and the computer is working hard to keep vehicles from all arriving at the problem area at once.