for the side issue of PADI’s dive definition:
From the 2007 PADI Instructor Manual:
From the 2007 PADI Instructor Manual:
In the 2012 IM:For training purposes, an open water dive is a dive during which a student diver spends the majority of time at a depth of at least 5 metres/15 feet and:
a. breathes at least 1400 litres or 50 cubic feet of compressed gas.
OR
b. remains submerged for at least 20 minutes.
A psi criterion would be strange because how much gas that represented would depend on the size of the cylinder.During open water dives, have divers spend the majority of time at 5 metres/15 feet or greater, and breathe at least 1400 litres or 50 cubic feet of compressed gas or remain submerged for at least 20 minutes.