Passenger Assistance Alarms (PAAs) are the black and yellow strips located above the windows and at the ends of subway/RT cars. Press the alarm strip immediately if you see or experience an incident that should be reported or stopped.
They should be used to report:
--- Threats to Customer Security
Here is what happens when the PAA strip:
--- An alarm goes off in your car and also in the driver's and guard's cabs.
--- A light on the outside of your car turns on so that it is easy for emergency personnel to see where the problem is.
--- The driver calls for emergency assistance.
--- The train stops at the next station and the doors open.
--- The subway guard or the RT driver will check the situation and take appropriate action.