At what distance is it mandatory to wear a cranial when the APU is operating?

Wearing a cranial at the mandatory distance of 50 feet when the Auxiliary Power Unit (APU) is operating is essential for safety. This distance is determined by the potential hazards associated with the APU, which can include exposure to high noise levels and the possibility of debris being expelled. The cranial provides necessary protection against these risks, particularly in a naval aviation environment where personnel may encounter unexpected situations.

Understanding this specific distance helps ensure that all personnel are adequately protected when they are in the vicinity of equipment that has operational concerns, such as the APU. This practice promotes a safe working environment and encourages adherence to safety protocols among ground crew and other personnel involved in aviation operations.