What are the flashing white lights on top of traffic lights when fire equipment passes?
The fire equipment and ambulances have a traffic control device on each vehicle that can change the traffic signals to green thus providing a safer and expedient response. The flashing white light indicates to responding vehicle that the light will turn green for them. The other lights on top of the other poles give a steady white light to let other equipment that may be responding from another direction know that the signal is controlled by another vehicle.
