What should divers do if they are unable to share air with a buddy during an out-of-air emergency?

In an out-of-air emergency, if divers are unable to share air with a buddy, activating an emergency buoyancy device can be a critical step. This device can help the diver achieve buoyancy, allowing them to ascend safely while managing their ascent rate to avoid complications such as decompression sickness or barotrauma, which can occur during rapid ascents. By preserving the ability to control buoyancy, the diver increases their chances of reaching the surface safety while conserving energy and ensuring that they do not become an additional risk to themselves or others in the water.

When considering other options, swimming to the surface independently can lead to dangerous situations if the diver ascends too quickly or if they experience further difficulties. Looking for another diver could divert attention from their own emergency, potentially leading to confusion and increased risk. Signaling for a boat or surface support is a viable option but may not be immediately practical in all situations, particularly if the diver is low on air and time is critical.

Thus, activating an emergency buoyancy device offers a direct solution that enables the diver to maintain control in a potentially life-threatening situation.