In the event of an out-of-air emergency, what is the first action a diver should take?

In an out-of-air emergency, the most crucial first action a diver should take is to signal for help. This allows the diver to alert their buddy or nearby divers to their situation and seek assistance to prevent a life-threatening scenario. Effective communication is vital in diving, especially during emergencies, and signaling can lead to a quicker response from fellow divers who can provide air or assist with a safe ascent.

Attempting to ascend immediately without communicating can lead to panic and poor decision-making. Divers may not realize that help is available or may not be aware of their surroundings, which could further complicate the situation. Performing a safety stop is important during routine ascents but is not a priority in an emergency where immediate help is needed. Using a dive slate to communicate may not be practical or effective in a situation where urgent action is required; diver-to-diver signal communication is typically more effective in emergencies.