What is the main hazard of stopping a rotating spindle with your hands?

Stopping a rotating spindle with your hands poses significant risks, primarily due to the potential for severe injury. The main hazard arises from the force and momentum of the moving spindle, which can result in hand lacerations, fractures, or crush injuries. When a spindle is rotating, it has considerable kinetic energy, and by attempting to halt it manually, one's hands may get caught or impacted by the spindle or adjacent machinery.

In contrast, while breaking the spindle (the first choice) is a concern, it is secondary to the immediate physical risk to human safety. Slowing down the machine (the third choice) does not capture the hazardous nature of direct hand contact with a moving part. The idea that it is safe to stop a spindle with one’s hands is fundamentally incorrect and disregards safety protocols. This highlights the importance of using appropriate tools and safety measures to stop or disengage machinery safely, emphasizing that hands should never be used for such purposes.