What type of safety develops retarding force during the compression stroke of one or more buffers?

The correct answer is C, which refers to Type C buffers. These buffers are specifically designed to develop a retarding force during the compression stroke, effectively managing the impact energy of the elevator car as it approaches the lowest position. This design is crucial for ensuring safety in elevator operations, as it helps to decelerate the car gently and prevents damage to both the car itself and the hoistway.

Type C buffers typically utilize a hydraulic system or a specific material that compresses and absorbs energy during the stroke. This mechanism allows for a smooth deceleration and enhances the overall safety of the elevator by providing a reliable method of cushioning the car’s descent.

In contrast, Type A and Type B buffers may use different methodologies or designs that do not focus on the compression stroke in the same manner as Type C, which is why they do not fit the description of developing retarding force during that phase. Understanding the nuances of each buffer type and their specific functions helps in selecting the appropriate safety features for elevator installations and maintenance practices.