Air Sharing: What We Teach and Why

Share airStudents in Underseas Scuba Center’s beginning scuba courses learn that, when another diver comes up to you and gives the “out of air” signal, you:

  • Don’t wait for that person to locate your alternate-air-source (“octopus”) second stage, take it, and then begin breathing from it without your assistance.

  • Don’t waste time fumbling around, looking for your alternate-air-source second stage so that, when you finally locate it, you can pass it to the out-of-air diver.


Instead, our students learn that, as soon as they see another diver give the “out of air” signal, they are to take no more than two deep breaths from their primary second stage (the one from which they normally breathe) and then pass it to the out-of-air diver. Only after they pass this second stage are they to locate their own alternate-air-source and begin breathing from it.

Why do we teach this? »