If a diver runs out of air and their buddy is close by, what is the best option?

Utilizing a buddy's alternate air source is the optimal action if a diver runs out of air while having a close buddy. This approach allows for a safe and controlled ascent while still being able to breathe, significantly reducing the risk of hypoxia (lack of oxygen) during the ascent. The buddy can provide their alternate air source, ensuring the diver can maintain proper buoyancy and control while ascending. This method encourages good diving practices, emphasizing the importance of buddy systems and teamwork in scuba diving.

In situations where a diver runs out of air, it is crucial to avoid making a controlled emergency swimming ascent without a proper air source since it can lead to rapid ascent, risking decompression sickness or barotrauma. Signalling for immediate assistance, while valuable, does not provide an immediate solution to the immediate need for air. Swimming to the surface without assistance poses significant risks, including uncontrolled ascent and the inability to manage buoyancy properly, increasing the likelihood of injury. Therefore, using the buddy's alternate air source aligns with safe diving practices and emergency protocol.