The use of modern elevators started way back in 1857. So why do we keep hearing about elevator accidents.
Are Elevators Really Safe?
Are elevators really safe? Elevator expert and consultant Charles A. Buckman says they are: “Riding in an elevator is safer than riding in a New York cab, for example. Elevators are the safest mode of transportation in the country, without exception.”
Need numbers to settle down your pitter patter heart every time you ride one? How about 0.00000015%? This is the probability of any accident happening during one of the 18 billion trips made in one year!
How Safe Are They?
Occupational Health & Safety (2009) reported the presence of a redundancy of safety features on elevators, making the risk of elevator failure next to impossible. Some of them being:
Cables: Elevators can have anywhere from 4-8 times more cables to hold them in place than they require. This number depends on a ďfactor of safety.Ē For a building that has a 12 factor of safety, it means all the ropes must hold a mass that is 12 times that of a fully loaded car. You can take it to mean that each cable is strong enough to hold more than the car itself weighs!
Automatic Braking Systems: Present at both the top and bottom of the shaft. Working in case of an error in the safety chain, these brakes do not function in a way car brakes do. When the clamp stops the pulley present above the car, the elevator stops moving. It will stay there unless there is power that releases it, which means you are safe, in case of power failure.
Electromagnetic Brakes: These brakes are further protection, found at the bottom of the elevator. In case of an overspeeding elevator, the brake gets jammed into a channel found in the metal rods along which it travels. As friction builds, the car comes to a stop.
Shock Absorber System: A heavy-duty absorber is found at the bottom of the shaft.
Counterweights: On both ends of the cables, is a set of counterweights, which are slightly heavier than an empty car. If all the emergency systems fail to kick in and there is a single passenger inside, these weights make the elevator go up rather than descend. In case of a fully loaded car, the descent is slowed down to make it safer.
Pre-Run Checks: Automatically done by the elevator, if something is found to be amiss, power to the motor will be cut, and brakes applied. Examples are the door being open, overspeed or the emergency stop button has been pushed etc.
What You May Not Know About Modern Elevators
- That button for closing the elevator door you keep pressing? Yeah, does not work! Ever since the 90s, only the key held by authorities can do that.
- The only incident with a snapped cable happened in 1945.
- Elevators are safer than escalators Ė about 20 times safer.
- The purpose of inventing Elevator music was calming fearful passengers.
- The amount of people that use the Otis Elevator Company in five days are the equivalent of the population of the world!