Any rules with combining scuba and freediving

[chiel]

Hello all,

Next week i'm of to the Caribbean and I will be doing some scuba diving and also some freediving.
For scuba diving there are rules that you can't dive for a certain amount of time between dives, however when I dive I only do one a day so thats no problem.

But are there any rules, before or after, for freediving when you just did a scuba dive?
For example, if I did a normal scuba dive (max 18 meter) must I wait for a min amount of time before I can go freediving? or can I do I directly afterward?

I freedive to about 20 meter.

 

[Dave1981]

Personally I will freedive before scuba, though always leave it an hour or more after scuba. It's not based on anything other than my own opinion, which is that if you're already loaded up with nitrogen then repetitive bounces cannot be doing you any good.

I figure if you maybe have a bit of sub-clinical dcs then the pressure cycling may exacerbate bubbles that otherwise would not be a problem. Just my opinion. If it's been one particularly light dive in a day I'd take that into account, if I'd been in the water every day for a considerable period I'd consider that too. I don't know if there is a real rule for it anywhere? I'd be interested to find out.

 

[PfcAJ]

I'd hold off on the freediving after scuba for about 4 hours. When you freedive, the pressure can shrink the bubbles in your blood (there is always some post dive bubbling), allowing them to pass through your alveolar capillary bed. Once you ascend, those bubbles (now on the arterial side) will re-expand and could cause serious issues.

This is the same reason why it's not smart to bounce dive.

 

[The Chairman]

I don't know that I have seen a formal recommendation on this at all. I would wait an hour or two, and even then take it easy. Too much exercise can create a DCS episode.

 

[Rainer]

No problem surface snorkeling after scuba diving, but I wouldn't freedive after scuba diving for several hours to avoid possible bubble pumping.

 

[daniel1948]

I have been told not to freedive after scuba until the following day. I've also been told just to wait an hour or several.

My rule for myself is that if I am going to freedive and scuba dive on the same day, I'll do the freediving first, and the scuba after. Never the other way around. Why take chances?

As noted above, it's because of the effect of the bounce diving on the micro bubbles that are always present after scuba. I don't think there have been the same sort of quantitative studies of the behavior of nitrogen in the body when freediving after scuba diving that there have been on scuba diving alone at various depths, times, and decompression schedules. In the absence of such studies, it's best to play it safe, and do your freediving before, rather than after scuba. Or do them on separate days.