What should a diver do if they have not surfaced as expected?

If a diver finds they have not surfaced as expected, sending a signal immediately is the correct action to take. This approach is critical for ensuring the diver's safety. By signaling, the diver communicates their situation to the surface support team, which can initiate a prompt response. Quick communication allows for the implementation of safety measures, such as initiating a search or preparing emergency procedures.

Having a clear protocol for signaling in such situations is paramount, as it helps in rapidly identifying and addressing potential issues, like entrapment or an equipment failure. It emphasizes the importance of maintaining contact with the surface team during a dive to ensure safety and coordination.

In contrast, acting on impulse, such as panicking or ascending quickly, can lead to increased risks associated with decompression sickness or barotrauma. Checking equipment is also essential, but it should be a part of a diver's preventive measures before descending, rather than a primary reaction to an unexpected situation. Waiting for the dive supervisor to react without taking immediate action can lead to delays and worsen the diver's condition, especially in emergency scenarios.