Elevator "don't panic" signs

Elevators have a lot of safety devices that protect passengers if something should go wrong with the elevator. However, not everyone knows a lot about elevators, so some people stuck in an elevator may fear that a broken elevator could free-fall to the bottom and crash. Also, in some elevators, the vents are not clearly visible, so people may not know they are there, and fear that they will "run out of air". Both of these unpleasent thoughts may lead to panic among passengers.

I think that elevators should have a sign posted in the elevator that tells passengers about the presence of the fall arrestor and the ventilation in the elevator.The sign should also list a number for whatever company services the elevator, and state that a passenger should use that number if they are simply stuck in the elevator and there is no immediate danger, but if there is a true emergency (worse than simply being stuck in the elevator, like a passenger has a medical condition or something like that) that they should dial 911.

How do they dial different numbers? Via a speaker-phone that is mounted behind a cover! The phone will have a keypad, with braille beneath each button (which would call for additional space between the buttons) and an on/off button, again marked in braille. The sign, as well as the phone number, will have a braille translation below it, making it ADA compliant.

This is in contrast to a pre-programmed speaker phone that simply has a call button that calls the number programmed at installation. There's also a button that can play a pre-recorded message over the phone, with a light that says "blinking indicates call has been acknowledged help is on the way" which will come on when the person _on the other end_ ends the call. This light won't come on if the passenger is the one who hangs up, to avoid giving them a false message.