Interface: Operation Green Light Field Equipment - County and City Emergency Vehicles
![Operation Green Light Field Equipment to County and City Emergency Vehicles Interface Diagram](../../images/ifs/if45-159.gif)
Architecture Flow Definitions
local signal preemption request (Existing) Applicable ITS Standards
Direct control signal or message to a signalized intersection that results in preemption of the current control plan and grants right-of-way to the requesting vehicle.