What should divers do if they experience dizziness or lightheadedness underwater?

If divers experience dizziness or lightheadedness underwater, signaling for assistance and beginning a controlled ascent is crucial for their safety. These symptoms can indicate a variety of potential issues, such as decompression sickness, hypoxia, or other physiological stressors that can compromise the diver's ability to function effectively and safely.

By signaling for help, divers ensure that they can receive immediate support, which is vital in case their condition deteriorates. A controlled ascent allows them to safely rise to the surface or to a depth where they can receive aid without risking further injury or complications, such as sudden ascent-related injuries or exacerbating any underlying issue contributing to their symptoms. Maintaining a proper ascent rate is essential in avoiding pressure-related injuries.

Continuing to dive or ignoring the symptoms could lead to more severe consequences, while swimming to the nearest exit point might not be safe if a diver becomes incapacitated. Therefore, the safest and most prudent action in such situations is to seek assistance immediately and prioritize a controlled ascent.