Have you ever wondered how we process traffic signal information? It all starts with our early driving experiences and actually, over time, we learn to automatically block out traffic signals during our daily commute. That is, we block out the signals until we get caught at lengthy, numerous red lights over a relatively short distance. At that time, our focus then turns to the nuisance they cause – long delays to our final destination, road rage, and misconceived notions about the benefits of traffic signals (or lack thereof).
In reality, the purpose of traffic signals is to solve traffic conflicts. We all want to be in the same place at the same time, but this would only lead to accidents, severe traffic jams, and ultimately, chaos.
To help you and those motorists out there, there are a number of preconceived ideas about traffic control that are absolutely incorrect and lead to frustration and unnecessary stress. I’d like to share the 7 myths that motorists actually believe about stoplights and other traffic signals.
Myth #1: The Flasher. If you flash your car’s high beams at a stoplight, it will turn from red to green more quickly.
Reality: Traffic light sensors do not detect headlights; they use other means to detect traffic at a light. Emergency light sensors read encoded and proprietary infrared signals from special emitters installed in emergency vehicles.
Myth #2: The Pusher. If you push the pedestrian crossing button multiple times or in a set pattern, you can trigger a green light faster.
Reality: While many of us are guilty of pushing the cross button over and over, it has no impact on how quickly the signal changes. When you push the button, the event gets recorded in the memory of the traffic signal controller (just as if you push an elevator button). This signal is then used to time the light change, nothing more.
Myth #3: The Weight-Builder. The amount of weight present at an intersection triggers a green light.
Reality: The weight of a vehicle has nothing to do with triggering a green light indication. Vehicle presence is detected by inductive loop technology, which works on the principle of electromagnetic induction, and all that is necessary is a vehicle having sufficient iron in the metal for detection and stopping over the inductive loop which signals the traffic controller that there is traffic waiting at the intersection.
The only vehicles potentially affected may be motorcycles or mopeds, but this can be overcome by drivers pulling near the corner of the lane near the stop bar painted at the intersection.
Myth #4: The Unseen. Traffic lights are changed by tripping an invisible curtain that covers only a section of the lane.
Reality: Vehicles trigger the inductive loop (see Myth #3), and as long as they have sufficient metal and stop in the right spot – just before the stop bar, the thick white line painted on the pavement that signals to motorists where they should stop in order to be effectively detected by the traffic controller.
Stop too far past or before the bar and the pavement sensors can’t detect your presence. As a result, motorists who do not stop at the stop bar generally end up waiting longer at intersections!
In order to be detected, motorcycles and bicycles also must stop before the stop bar. The in-pavement detectors are most sensitive at the corners. So, motorcycles have a better chance of being detected if they stop at the corner of the lane just behind the stop bar too.
Myth #5: Remote Controlling. You can turn the stoplight green through the use of a universal television remote.
Reality: You cannot program a remote with a special code in order to change traffic signals. This myth stems from an Internet spoof and holds no truth. Sensors associated with preemption systems are programmed to only detect certain infra-red signals from emergency vehicles and cannot be fooled or tricked into activating a green light for passenger vehicles; and for good reason.
Imagine the chaos if every impatient driver with access to a Radio Shack, took it upon himself to direct traffic according to his whims!
Myth #6: Big Brother Is Stopping You: Governments or cities purposely implement policies that do not allow traffic to efficiently flow through intersections.
Reality: Most traffic lights are poorly timed and inefficient because transportation agencies don’t have the personnel or financial resources to update their timing plans or implement newer traffic technologies that could reduce delay at intersections. Without experienced personnel or money for updates and improvements, cities are unable to improve the efficiency of their traffic control systems and motorists, by default, are stuck wasting time and fuel at red lights.
Myth #7: The Safety Patrol. Traffic signals always reduce collisions.
Reality: The key word here is “always”. Traffic signals do help prevent collisions, but since only 40% of collisions occur at intersections, and drivers often get into accidents by trying to beat a red light or disobeying traffic rules, the truth is that poorly timed signals will not eliminate human actions, and therefore, will not eliminate all accidents.
Nevertheless, optimizing traffic signals to mitigate traffic conflicts is in the best interest of everyone. Coordinating traffic signals can reduce driver frustration, cut down on the number of cars running red lights, and decrease the number of traffic accidents occurring at our intersections.
Motorists form their own opinions based on urban myths about traffic signals and controls. Our job, as traffic experts, is to minimize the number of traffic aggravations experienced by motorists.
The ultimate goal is signal optimization for each and every thoroughfare – this can be accomplished through synchronized traffic signals, vehicle detection systems, and communication between intersections.