In 1854, a pioneering inventor would change the history of passenger lift solutions forever.
During the Great Exhibition at New York’s Crystal Palace, Elisha Otis would stand on a lift platform and ask an assistant to cut the rope. Once he did, the platform demonstrably held, showcasing the lift safety brake for the first time.
This is one of many features designed to protect the occupants of a lift in the already highly rare event that a cable snaps, but it is far from the only one.
The first safety feature is redundancy; there is not just one steel cable but multiple, typically between four and eight. They are regularly inspected for failure points, damage, fatigue or general wear and tear.
A single cable snapping without an inspector spotting the potential risk is already a rare occurrence, but the existence of redundancies means that a snapped cable is simply replaced with another one just as strong.
However, what if all the lift cables snapped? The safety brakes would kick in, clamp the rails or wedge between notches and safely slow the lift down.
This was the system Elisha Otis pioneered in 1854. At the time, lifts were relatively untrusted because they were such a new technology, but the demonstration showcasing one of its simplest and most effective safety features was a major revolution in lift design.
In most cases, these two safety features will safely cushion any fall, but what if, somehow, all the safety brakes failed? Would the lift simply plummet to the bottom? Not quite.
Lift shafts are designed to provide friction on the way down, slowing the lift car significantly, whilst compressed air and shock absorber systems installed at the bottom of the lift shaft would safely cushion the impact in the same way a SAFER crash barrier does in motorsport.
This makes the impossibly unlikely event of a lift car falling down a shaft far safer, and whilst it will typically take emergency services to get you out, you will typically escape serious injury.