■ Out of Air and Regulator Failure

If you experience an out-of-air situation and your buddy is nearby, signal immediately and use your buddy’s alternate air source (octopus) while making a controlled ascent together.

If your buddy does not have an alternate air source available, follow the trained emergency air-sharing procedure and ascend in a calm and controlled manner.

If no buddy is available and you are equipped with an independent air source such as a pony bottle, switch to that supply and ascend safely.

Alternate Air Source (Octopus)

Controlled Ascent with Alternate Air Source

If no buddy or independent air source is available, perform a Controlled Emergency Swimming Ascent (CESA) if appropriate and within training limits.

If necessary, perform a buoyant emergency ascent while continuously exhaling and maintaining an open airway.

If any air remains in the cylinder, breathe normally and ascend while exhaling slowly and continuously. Never hold your breath during ascent.

Controlled Emergency Swimming Ascent (CESA)

Buoyant Emergency Ascent