Costas Bakopanos
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Are you shilling your software? A disclaimer might make this seem less sketchy.
As a matter of fact yes and apologies if it was not clear.
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Are you shilling your software? A disclaimer might make this seem less sketchy.
@rjack321 and @kensuf
I was writing some long defense of 1.4 and wanting a better explanation of why 1.2 and bam there it is. The TDI books just refer to dialing back the PO2 if expecting heavy work or multiple dives over multiple days - no real tie of PO2 and He and Ox Tox........
Interesting reading and a good enough reason for the decrease.
Coming from someone who is curious about taking AN/DP/Helitrox at some point... Is the recommended ppO2 of 1.2 only for tech or is the general consensus that all diving should start switching to 1.2? What do you seasoned techies do when diving a benign dive above NDL?
Coming from someone who is curious about taking AN/DP/Helitrox at some point... Is the recommended ppO2 of 1.2 only for tech or is the general consensus that all diving should start switching to 1.2? What do you seasoned techies do when diving a benign dive above NDL?
This. Oh heavens, this. I really wonder how many lives have been damaged because of not getting this.your deco isn't a penalty for doing a dive, it's part of the dive itself.
If you want to run a ppO2 of 1.4 for bottom gas knock yourself out. I gave you a dramatic case of how that can bite you in the butt. I was taught 1.2 for the working phase over 15 years ago (and multiple times since then). 1.6 for deco/at rest.
21/17 @ 150ft (ppO2 1.16) for 20mins has 41 mins runtime (GF 50/80 on EAN50)
25/17 @ 150ft (ppO2 1.38) for 20mins has 39 mins runtime
Your choice saves 2 minutes on the ascent but comes with more risk.
It seems to me that when one gets into the tech realm, there's a hazy line between standards and personal preferences. Some agencies still teach deep stops. Experienced divers' personal preferences are often grounded in literature they have read and their own experiences. Your instructor's and Richard's "preferences" versus TDI's "standards" .... It's all grounded in more than whim and all worth taking in ... at some point.
The working portion of a dive is not necessarily the bottom part. I've done several dives where the deco portion is much more physically demanding than the bottom portion.
Example: Empress or Ireland -> no current on the wreck at depth but 2.5 to 3 knot current above 50 feet. Drift deco here would be a VERY bad idea as fog is common and the boat would never see your SMB. So you have to come up the line.