#897: Elevator Inspection explain

[Two Cueball-like guys and Ponytail, lifting her arms above her head, are in an elevator. Cueball standing next to the door reads the sign above the control panel.]

Cueball: It says here that the elevator inspection certificate is on file in the building office.

Friend: Whoa, cool! Let’s go look at it!

Ponytail: That sounds fun!

[Caption below the panel:]

Industry tip: Building owners know this never happens. Those signs mark elevators which have never been inspected.