What is the frequency range for whistle signals?

The frequency range for whistle signals in maritime communications is primarily within the range of 75-200 Hz. This frequency spectrum is specifically utilized to convey alerts and signals effectively over long distances, particularly in environments where other forms of communication may be limited, such as during fog or heavy precipitation. Whistles are designed to produce sounds that can carry well through the air and across water, making them an essential tool for signaling distress or maneuvering intentions.

The chosen frequency range also falls within typical sound levels that are easily recognizable and distinguishable from background noises, ensuring that they can be effectively heard by other vessels or personnel nearby. In contrast, the other options either fall too low or too high in frequency, which would not be practical or effective for producing clear whistle signals in a maritime setting.