In some elevators there is a stop lever for emergencies, but I found out it cleared all the selected floors as well. So in my building if I've made a mistake or a kid selected all the floors, I can just flip the stop toggle and reset everything.
In my building there are fire extinguishers for emergencies, but I found out they produce a really amazing snow-blanket effect even when it's not Christmastime.
OMG, this brings out memories about that oh so tempting red stop lever I was absolutely NOT allowed to touch as a kid. I haven't remebered that for decades..
One time our neighbor forgot her phone and activated the stop in the small elevator just as the doors were closing and it started going down. It stopped but already moved down and got stuck between floors. We were inside with our small child and it was not pleasant. Luckily, after resetting the switch and pressing some buttons, the elevator continued on its way.