Decompressing on way up.

[cody909]

When freediving do you have to decompress like SCUBA?
I was trained while SCUBA diving never to go up quicker then your smallest bubble?

Do you need to do the same for freediving to prevent decompression sickness?

Thanks
- Cody

 

[efattah]

Search the forum, there are many threads on 'freediving DCS'. The short answer is that if you dive 20m or less, you have nothing to worry about. At 30m, it depends on your surface intervals, dive time, and ascent rates. At 40m+, you can get bent after just a couple of dives if you come up really fast, and even worse if your surface intervals are short and your dives are long.

 

[azapa]

To support Erics answer, Alfredo March, top Spanish spearo, just got bent again at the Spanish nationals. His deepest shot fish was at -47M. He typically does 20 to 40 dives over 40M in a 3 to 6 hours comp. Extreeme case of course, but it does happen.

 

[cody909]

Thanks, You answered my Question, Ill only be diving in -45ft max,
:]]
Thank you

I doubt there i a question i can ask on this forum that someone cant answer.
Nothing like getting answers from the pros :]]

Thanks much
- Cody

 

[fcallagy]

Cody one other point no freediving after scuba there are no tablesto say how long a surface interval should be treat it like a no fly situation.be aware of it anyway if you have any dcs concerns.

 

[cody909]

one other point no freediving after scuba

Wait, If i read it right, I cant free dive after scuba diving?
I dont understand...
I know the Scuba Tables and how like for instance you can say under at 45ft for 55 minutes and how it increases and what not.

But i dont understand why? Because of the nitrogen, Good thing you pointed it out because i was gonna rent 3-4 tanks and when those were gone i was gonna free dive :]

Thanks
Cody

 

[trux]

But i dont understand why?

Because there is still more nitrogen in your body than normally. The freediving, where you do several descends (even if they are quite shallow) acts similarly as if you shaked a bottle of soda - the nitrogen in your body liquids starts creating bubbles.

 

[..Sam..]

3-4 dives in one day would put you pretty close to the edge without freediving, I'm assuming there at a reasonable depth otherwise you could probably snorkel it. There are two things you could do. Only freedive, only scuba or freedive first them scuba.

Less to no residual nitrogen in your system after shallow freedivers than shallow scuba. Freediving after scuba pressurizes (descent) and then very quickly unpressurizes (ascent) residual nitrogen in the blood from the scuba dive, it basically simulates a rapid ascent while on scuba, which is not good. Freediving after scuba basicly means lots of rapid ascents = not good.

Mind you I could be wrong, I'd like someone else to confirm.

 

[fcallagy]

Mind you I could be wrong, I'd like someone else to confirm.

No your right. ideally treat like no fly times as there are no tables to allow nitrogen offloading and recompressing with fast ascents.
Cody look at your ascent rate on scuba and then think of your ascent rate freediving. approx 10m/min and 1m per sec then think that you are in essence recompressing those nitrogen bubbles again and making a fast ascent with no stop. You might get away with it and you might not so theres no point in guessing. the offgassing would depend on your body weight, dehydration levels and fitness etc and these are all variable as well as the depths and duration of the dives but if 3 dives in a day regardless of depth you are going to be pretty saturated.
This is not just hearsay either a member of this forum got bent exactly like this.
Hope you enjoy your trip.

 

[cody909]

Thank you tons, I guess it will be freediving (Playing around) then SCUBA diving (Relaxing) ahaha

Sooo complicated,
Thanks tons guy
I will enjoy

Thank you
Cody