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And I got up the pool ladder from deep end twice with doubles on. Needed pulls on manifold, but I don’t care. This alone is major improvement. I’m putting in 45-60 min 3-4 times a week on the recumbent bike at the gym.
Except 80% is a lame choice of deco gas. That one is certain.
Please elaborate and give us your insight. As I’ve been preparing for my AN/DP/Helitrox course, I’ve been doing a lot of side reading, and I am intrigued by the idea of decompression oxygen vacations. Especially on 100%. So I’d like your insight on why 80% is lame.
For starters, O2 is the most effective deco gas. Zero inerts. You can deco at the same effectiveness anywhere between 20 and the surface, so you have the option of staying at 20 or ascending. For where you're going to spend the bulk of your time on shallow deco, between 20 and the surface, 80% has a lower PO2 and relies on changes in pressure gradient to offgas efficiently. You're also spiking your PO2 deeper when you switch at 30ft, so depending on what intermediate gas you used, you might be increasing your O2 exposure. It's also only 1.53 at 30ft, so by the time the gas gets to your blood, it's even lower. You're gonna make up that shortened 30ft stop on O2 later, so the time will work out even. But you'll have the flexibility and efficiency of O2 throughout your shallow stop instead of an inefficient gas.
You can do a dive profile where 80% mathematically clears deco a couple of minutes faster. That is a computer model and ignores real world practicality, execution, and safety margins.
Other than mathmatical modelling that many of us rely on in the form of deco software, what other benchmark do you suggest to tell us when we have successfully eliminated inert gas to a safe level?