Safeties

Safeties
The purpose of the safeties is to stop and hold the car if the speed is too fast, the ropes have slack in them, or the car is in a free-fall. The safeties are attached to the safety planks under the car.
There are three types of safeties: Type A, B, and C.
Type A
Brings car to an immediate stop. Can only be used on speeds under 151 fpm (0.77 m/s). Type A safeties are the least expensive.
Type B
Brings car to a gradual stop. Can be used on any speed.
Type C
Brings car to a gradual stop. Can only be used on speeds under 501 fpm (2.55 m/s). This is an older design that is rarely used.
Note: If the space below the hoistway is occupied, safeties are also required on the counterweight.