Which hand signal is used to stop the motion of a traveling crane in the normal course of operation?

• A. holding the palm of your hand up with your fingers closed, pointing your thumb in the direction of motion, and jerking your hand horizontally
• B. extending your arm forward with your hand open and slightly raised, and making a pushing motion in the direction of travel
• C. extending your arm with the palm of your hand down, and moving your arm back and forth horizontally
• D. holding your forearm vertical with your forefinger pointing up and moving your hand in a small horizontal circle

Answer: (C)

In traveling crane signaling, stopping the motion is communicated with a clear, standardized gesture: extend your arm, palm facing downward, and move your arm back and forth in a short horizontal motion. The palm-down, side-to-side movement is distinct and unambiguous, which helps the crane operator reliably halt travel even if visibility or timing is challenging. Other gestures use different orientations or motions (for example, a palm-up with a quick jerk, or a forward push, or a vertical forearm cue), and they indicate other instructions rather than stopping travel. So the palm-down, back-and-forth signal is the correct one to stop the crane.