Question 548Deck General70% to pass
The signal man assisting the crane operator has his arm extended, his fingers closed, and his thumb pointing downward. This is the signal to _______________.
AI Explanation
The correct answer is B) lower the boom.
When the signalman's arm is extended with fingers closed and thumb pointing downward, this is the standardized hand signal to indicate that the crane operator should lower the boom. This signal is defined in the ANSI/ASME B30.5 standard, which is the widely accepted industry standard for crane hand signals in the United States.
The other answer choices are incorrect because they do not match the specific hand signal described. Raising the boom, lowering the load, and hoisting the load would each have different standardized hand signals that differ from the one presented in the question.
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