Elevators in the elevator shaft are often the least-desirable type of elevator, with the shaft itself being the primary means of elevating people.

 In the United States, the National Research Council estimates that as many as 80% of all elevator shafts are unused, meaning they are no longer used for elevator service.

The majority of those unused elevators are in New York City and Los Angeles.

A few are located in places like Detroit, Chicago, and Pittsburgh.

While the shaft is often the primary transportation option for many people, the average elevator requires a high-voltage supply, an expensive elevator shaft design, and often a heavy load.

For this reason, the Institute of Electrical and Electronics Engineers recommends that any elevator shaft be designed to use a power supply of 10 to 30 watts.

If you’re using an elevator shaft and you need to get to work, check with the building manager.

This article originally appeared at The Conversation.

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