Which Category 2 operator aid helps determine hoist drum rotation when the operator cannot see the drum?

• A. Hoist drum rotation indicator
• B. Jib angle indicator
• C. Boom hoist limiting device
• D. Rail clamps

Answer: (A)

When you can’t see the hoist drum, you rely on an indicator that tells you how the drum is turning to control rope length safely. The hoist drum rotation indicator provides exactly that information—showing the direction and amount of drum rotation so you know how much rope has been wound or unwound even without a visual on the drum. This helps prevent over-winding, rope tangling, or mishandling the load.

The jib angle indicator only shows the jib’s angle, not rope or drum status, so it doesn’t help with drum rotation. The boom hoist limiting device is about restricting how far the boom hoist can travel, which is a protective measure for boom movement, not for monitoring the drum. Rail clamps relate to securing the crane to rails and don’t provide drum rotation information.

So the best aid in this situation is the hoist drum rotation indicator.