Water too deep to stand up in?

t’s a PADI standard but what exactly does it mean? Well if your tallest student diver stands flat footed on the pool bottom and would need a snorkel or regulator to breath as the water depth covers their mouth and nose, that is water too deep to stand up in. Today pools are getting shallower as they are more cost effective to build and less costly to operate. The days of four and even three metre deep pools are gone.