Read this: Dumbwaiters are small freight elevators that are intended to carry food, books or other small freight loads rather than passengers. They often connect kitchens to rooms on other floors. they usually do not have the same safety features found in passenger elevators, like various ropes for redundancy. they have a lower capacity, and they can be up to 1 meter (3 ft.) tall. there's a control panel at every stop, that mimics the ones found in passenger elevators, like calling, door control, floor selection.
Now answer this question, if there is an answer (If it cannot be answered, return "unanswerable"): What is a safety feature found in passenger elevators they generally do not have?
various ropes for redundancy