What is the maximum allowable distance for a fall arrest deceleration device to expand?

In fall protection systems, a fall arrest deceleration device must effectively limit the distance that a worker can fall during an arrest while ensuring that the forces exerted on the body are kept within safe limits. The maximum allowable expansion distance for such devices is typically set to maintain safety and prevent excessive swing fall hazards or impacts.

The correct answer is 3.5 feet, which aligns with commonly accepted safety standards for personal fall arrest systems. This distance ensures that the deceleration device can slow down the descedent's fall without subjecting them to dangerously high forces or allowing them to collide with lower-level surfaces. By adhering to this distance, workers are better protected during fall events, and the equipment remains effective in preventing injury.

This standard takes into account various factors including the dynamic forces of a fall, the characteristics of the harness and anchorage, and the human body's tolerance to impact forces. The other distances mentioned do not provide an adequate margin for safety or may not adhere to industry standards, making 3.5 feet the optimal choice for maximum allowable deceleration device expansion.