Regarding spotter signals, which statement is correct?

• A. Signals are optional if the operator is skilled.
• B. Signals should be audibly described only.
• C. Signals should be clear and understood, and the spotter may stop operations if unsafe.
• D. Spotter should only observe.

Answer: (C)

In crane safety, spotter signals must be clear and understood by everyone involved, and the spotter has the authority to stop operations if conditions become unsafe. This ensures that the operator only moves the load when there is unambiguous, validated guidance from the spotter, reducing the risk of collisions, tip-overs, or other accidents. Signals should be standardized and usable in the actual work environment—visible in poor lighting or sun glare and audible if background noise allows—so both parties can reliably interpret them. The spotter’s role is active: observing, communicating, and stopping the lift if anything looks unsafe.

Signals being optional ignores the safety requirement for clear communication. Limiting signals to audible descriptions can be insufficient in noisy environments or when visibility is critical. Spotters are not there only to observe; they actively direct crane movements and must have the authority to halt operations when necessary.