At what distance is it required to wear a cranial with the engines turned on?

Wearing a cranial helmet, also known as a flight deck helmet, is crucial for ensuring safety around aircraft engines that are running. The requirement for wearing a cranial is particularly critical in order to protect personnel from both noise and potential hazards such as debris that can be kicked up by the engines' exhaust.

The correct distance of 100 feet aligns with established safety protocols, which dictate that personnel must don cranials within this range of operating engines. This distance takes into consideration the noise levels that can exceed safe limits and the risk of injuries from foreign object damage (FOD) or blasts from the engines.

Understanding the importance of this safety measure reinforces the significance of adhering to established guidelines to minimize the risk of injury while working around operational aircraft. Such protocols are designed not only to protect individuals in aviation environments but to promote a culture of safety and awareness on the flight deck.