Elevator manufacturers Otis and Schindler began incorporating them into their elevators at this time.
These holes have been required on elevator doors since the 1970s when new fire codes began to require them. These landing doors are also opened with this key when the elevator needs to be repaired or inspected, whether the cabin is present on that floor or not. This is when certain specific procedures are followed to get people out of the dangerous situation posed by an elevator between floors. This special key is inserted into the tiny hole in the landing elevator door and allows that door to be released and opened. The tiny hole doesn’t have an official name, though sometimes it’s referred to as an escutcheon or escutcheon tube (like the one in our ears). Firefighters and elevator technicians might even carry their own unlocking devices or drop keys. This can be in what is known as a Knox box, a place where important keys to a building are kept. Maintenance personnel and firefighters have access to a tool called a hoistway door unlocking device or drop key, which is usually kept in a secure location in the building that can only be accessed by approved personnel. This is where the tiny holes in elevator doors come into play. Most of the time, the elevator gets fixed and moves on its way before the keyhole is needed, but sometimes, the elevator needs to be accessed more quickly due to a more pressing problem such as a fire or panicked passenger. If an elevator stops and the cabin doors won’t open due to some mechanical or other problem, there needs to be a way for rescuers or maintenance personnel to get to the passengers if the problem can’t be corrected.
Elevators have two sets of doors, one opening to the floor called the landing door and another that is part of the elevator compartment, more specifically known as the cabin, cab, car, or carriage. Elevators are built with many safety features, and these holes are one of them. Quite simply, these tiny, round holes in elevator doors are keyholes. This would not be correct, but that tiny hole in elevator doors does have an important job. It is reasonable to assume that since it resembles a peephole like in a regular door, this would be what it is so that someone on the outside could look in on passengers of the elevator for some reason. While you won’t see it on every elevator door, many of them have one tiny hole in one panel of the door.