Which of the following are the ANSI/ASME audible signals?

• A. Stop, Forward, and Reverse
• B. Stop, Pause, and Reverse
• C. Forward, Backward, and Stop
• D. Stop, Forward, and Stop

Answer: (A)

ANSI/ASME audible signals provide a single, universal way to warn and coordinate with ground personnel when equipment moves. The three signals defined are Stop, Forward, and Reverse. Stop means halt all motion immediately; Forward tells the machine to move in its forward direction; Reverse tells it to move in the opposite direction. This small, fixed set keeps communication clear in noisy work environments and prevents misinterpretation that could lead to accidents. Other options introduce signals like Pause or use Backward, which aren’t part of the standardized set—Pause isn’t an official warning, and Backward isn’t the term used by ANSI/ASME (they use Reverse). On any site, rely on the documented signals, but these three form the standard baseline.