From Instructor's Manual, Confined water dive three, PADI:
10. Air depletion/alternate air source combined exercise — In water too deep to stand up in, close the “out-of-air” student’s valve. When student feels air loss (should not watch SPG), student signals out-of-air and secures buddy’s alternate air source and begins breathing. Reopen the valve as student secures the buddy’s alternate so the regulator is available for use. Donor and receiver swim together with receiver using alternate air source for at least one minute. Switch roles so all divers act as donors and receivers.
Been there several years. If you didn't do it in your PADI OW class, the instructor failed to follow standards.
This is a follow-up skill to the Air Depletion only exercise from Confined Water Dive 2, where the student watches their SPG while the instructor turns off the air. When depleted, they signal OOA and it is turned back on.
10. Air depletion/alternate air source combined exercise — In water too deep to stand up in, close the “out-of-air” student’s valve. When student feels air loss (should not watch SPG), student signals out-of-air and secures buddy’s alternate air source and begins breathing. Reopen the valve as student secures the buddy’s alternate so the regulator is available for use. Donor and receiver swim together with receiver using alternate air source for at least one minute. Switch roles so all divers act as donors and receivers.
Been there several years. If you didn't do it in your PADI OW class, the instructor failed to follow standards.
This is a follow-up skill to the Air Depletion only exercise from Confined Water Dive 2, where the student watches their SPG while the instructor turns off the air. When depleted, they signal OOA and it is turned back on.