When i got certed I remember my instructor talking to me about freediving during the SI as long as I kept my computer on. Matter of fact, I remember doing some shallow dives between my open water checkout dives. He recommended it as I recall...
Free Diver Gets Certified
- Thread starter Wojo
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When i got certed I remember my instructor talking to me about freediving during the SI as long as I kept my computer on. Matter of fact, I remember doing some shallow dives between my open water checkout dives. He recommended it as I recall...
Keeping your computer on and I assume with you on the free dive??? Why is it needed? You aren't absorbing any additional N2 since the breath you take with you is at 1 atm. If anything, this is going to result in very conservative repetive dives since the computer "thinks" you're breathing compressed air and will penalize you on bottom time for your next dives.
This is a horrible idea...please don't do it.
Free diving and then scuba is ok...
Scuba diving followed by free diving is bad practice at best, and flat out dangerous at worst.
I'm curious, why?
---------- Post added August 12th, 2014 at 03:23 PM ----------
After thinking about this for a while I think I know why. Before the (first) dive our tissues are saturated at 0.79 atm of N2. During the dive our tissues have picked up N2 at a partial pressure (pp) greater than 0.79. If we decide to freedive some of the tissue compartments will be offgassing. The worst case will be for a maximum NDL dive with a minimum surface interval. At the start of the freedive the lungs are charged with 0.79 ppN2. Since the tissues are offgassing the ppN2 in the lungs will increase above 0.79. This pp increases the total pressure in the lungs which are already at their near maximum volume. Upon ascent the N2 will expand and if the diver holds her breath could lead to an embolism. The solution would be to very slowly continuously exhale on ascent. Exhaling is probably not standard practice and will get the diver in trouble if forgotten.
---------- Post added August 12th, 2014 at 03:47 PM ----------
Correction: The solution would be to exhale periodically throughout the entire freedive.
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