How should a diver maintain communication with others underwater?

Maintaining communication underwater is crucial for safety and effective teamwork among divers. Signal and light methods are appropriate for underwater communication because sound travels differently in water, making verbal communication ineffective. Divers typically use hand signals to convey messages, which can include specific movements or gestures that indicate direction, depth, or any concerns. Additionally, using light sources, such as dive lights or flashlights, can help signal to other divers when visibility is low and can enhance the clarity of communication.

In contrast, shouting is not feasible underwater due to the way sound travels, which is significantly diminished compared to air. Radio communication is also ineffective, as traditional radios do not work well underwater due to signal attenuation. Lastly, written notes would not be practical in an underwater environment, where the pressure, buoyancy, and water conditions make it nearly impossible to write or read effectively. Therefore, the use of signals and light is the most reliable and effective method for diver communication under these conditions.