Join Date: Apr 2006
Thanked 173 Times in 170 Posts
Rep Power: 12
Re: DIY - discussion on building a DIY hookah diving compressor
Have you ever overeaten "until you were stuffed" perhaps at a holiday dinner? Stomache is fully distended, stuffed, but folks keep eating.
Similar for the lungs, they may be full but someone is tense and afraid to exhale and lose air. IIRC the lungs can burst with as little as a 4psi pressure difference, and the kicker is that normally there may be "thin spots" in the lungs, that present no problem when there is no pressure differential on them. But with compressed air, if a thin spot blows out, now you've got pneumothorax and a problem.
Akin to the way you may have been told not to hold your nose & mouth when you sneeze, because your lungs can blow out your eardrums.
I don't conciously exhale while surfacing, but I had problems learning to control my breath with an open nose in the water. Eventually "trained" my throat to just hold back the water pressure and on the way up, to allow air to leak out as it needs to. Which is probably not describing it accurately, but the air goes out and the pressure stays balanced.
Last edited by hellosailor; 05-14-2013 at 12:05 PM.