Can varying your SAC rate reduce/increase the likelihood of DCS?

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Wasnt the reason for doing stationary deco based in the higher PPO2 while doing deco?

I thought it was the other way around. You can have higher PPO2 because your not working as much. I'm not talking about running marathons, just a easy swim around. Beside, most of the time your not going to be at 1.6 anyway.
 
I thought it was the other way around. You can have higher PPO2 because your not working as much. I'm not talking about running marathons, just a easy swim around. Beside, most of the time your not going to be at 1.6 anyway.


I agree you can have the higher PPO2's for the reason you said. You cant have it both ways higher PPO2's and higher activity to increase the matabolism. The accepted practice calls for them to be mutually exclusive. The lower activity level should keep the off gassing down also to a controlled rate. Other wise I would guess that even if you have a delta pressure of 1.5 the activity would risk raising the effect to 2.0 or more. You could probably do that after a calm first minute or so when most of the high rate off gassing would be completed. Im no expert so I may be talking out my back side but this is what I get out of the pages of talk, reading, and then self reasoning. So in my view you maximize the PPO2 in exchange for the protection of minimum activity. If you want to be active you lower your max PPO2 which raises you N2 % and slows the off gassing. Kind of counter productive depending how you look at it.
 
i only dive in my drysuit... its been joked to me many times that the only people i can dive with are those on rebreathers. I wonder what it will be when i get a separate bottle for my dry suit inflation.

But its kinda annoying when I'm having to end dives and sometimes waste so much unused gas because I'm diving with people that have 'regular' SAC rates.

Teach yourself how to solo dive and just complete the dive yourself, your buddy should be able to get back on the boat or to shore themselves.

I always find the bigger issue is when dive operations limit dive time. Now that is endlessly frustrating (especially if there is no good reason). This is why I much prefer shore diving.

Now I don't find my air consumption goes down on the deco line. I think it is due to not having perfected my buoyancy control yet so to maintain depth I'm just breathing more than I should. Albeit not often over 10L/min so I can't really complain.
 
I'm pretty new to diving and trying to educate myself where possible and i wondered if there is a paper or resource someone can direct me to if this has already been discussed.

My SAC rate on deco is around 50% that of the 'working' portion of my dives, Thats not to say i increase my air consumption during the work portion, Rather it's more like when I'm not moving around much my gas consumption goes crazy low (around 5-6LPM).

It was after a dive recently where afterwards i thought about all the N2 i had taken on at depth (breathing 10-12 litres per minute) and then coming up to deco depths i spent around an hour there but it got me thinking that surely to offgas efficiently i should maybe deliberately increase my breathing rate to the same as the working portion of my dive where my SACrate is much higher.... Or am i just overthinking things?
I realise i relax to a zenlike state when I'm just staring at a fish or a rock and not really moving anywhere. :p


Can you offgas inspired nitrogen in the blood at a fixed rate independent of breathing or does breathing rate directly influence the efficiency of decompression?

Does a marginal increase in breathing rate on deco, compared to the working portion, assist in off gassing faster?

Actually, the way I understand it, working hard(er) on the bottom is more of a concern that being relaxed at deco. You don't need to be concerned so much about a marginal difference in off gassing as much as the increase in "on gassing" during the working phase of the dive.

If it's concerning you, you'll probably be better off leaving the bottom a couple of minutes earlier than extending deco.

R..
 
https://www.shearwater.com/products/perdix-ai/

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