Many people are now discovering that the small lights on top of traffic signals help emergency vehicles pass quickly and safely.
Many people are curious about the small lights on top of traffic signals.
Traffic signals have evolved significantly since their early gas-lit predecessors.
One of the most intriguing features of modern traffic lights is the presence of lights at the top of the signal.
These mysterious lights serve a vital purpose in ensuring road safety and efficient traffic low.
These are not cameras or warning lights, but part of an Emergency Vehicle Preemption (EVP) system.
What the lights at the top of the traffic signals are?
Emergency vehicle preemption system
This system, first introduced in the 1980s, allows emergency vehicles like ambulances, fire trucks, and police cars to communicate with the traffic signals.
When an emergency vehicle approaches, the light changes to green, allowing it to pass safely and quickly.
This system saves valuable time in emergencies.
How do the lights work?
When an emergency vehicle nears an intersection, the EVP system detects it.
The system then changes the traffic lights to create a clear path for the vehicle.
The EVP system uses a variety of technologies, including satellite tracking, infrared communication, and radio signals, to monitor the location and movement of emergency vehicles.
As the vehicle approaches an intersection, the EVP system can manipulate the traffic lights, turning them red for vehicles traveling in other directions.
This ensures that the emergency vehicle can pass through the intersection safely and without delay.
Technologies used in the EVP system
The EVP system uses a variety of technologies, including satellite, infrared, and radio systems, to track the location and movement of emergency vehicles.
The information is sent to the traffic light controller.
This controller adjusts the signal timing to create a clear path for the emergency vehicle.
The lights on top of traffic signals are not the main communication method.
Instead, they visually confirm that the system is active.
An important role of the lights in road safety
The lights on top of the traffic signals can either be solid or flashing.
In some states, a flashing light shows that the traffic light in the opposite direction is green.
A solid light means the traffic light in the same direction is green.
This visual cue helps other drivers understand the traffic signal status and react accordingly.
Besides emergency vehicles, the EVP system can also be used for other modes of transportation.
It helps prioritize the movement of buses and urban trains.
By allowing these vehicles to clear intersections more quickly, the system can help to improve traffic flow and reduce delays.
The information collected by the EVP system is also used by Advanced Traffic Management Systems (ATMS) to monitor and analyze traffic patterns.
This data can be used to identify areas for improvement and optimize traffic signal timing.
It can also help develop strategies to reduce congestion.
Success of the EVP system and recent enhancements
The implementation of the EVP system has been widely recognized as a success.
It has improved emergency response times and enhanced overall road safety.
In a recent announcement, the South Georgia Medical Center EMS Chief revealed that a “GPS-ready” feature was added to the EVP system.
This addition has reduced emergency vehicle response times by an average of 11 seconds.