Oh Man! Better to find out now than later, right after a big dive....good luck.. I found out 2 weeks ago I have a pfo I need to get fixed
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Oh Man! Better to find out now than later, right after a big dive....good luck.. I found out 2 weeks ago I have a pfo I need to get fixed
Oh Man! Better to find out now than later, right after a big dive....good luck.
I had mine closed. Absolute game changer. 10/10 would recommend.I got a few undeserved hits on a few simple Ginnie dives and one non tech ow dive. I changed my GFs and made some other changes and haven’t had any big hits since. When they occurred 5 years ago I got tested by a local cardiologist and was negative. Kensuf and some other people told me to get retested so I went to see Dr Ebersole and they found a small one. I plan to get it closed but would prefer to see Dr Ebersole but he and the hospital he does them out of are out of network for my insurer so it’d be $15k plus. My wife’s just finished her master’s and is in the job hunt so I’m waiting to see if her new insurance would cover me. If not I’ll go to Gainesville to see a cardiologist who’s also closed a few divers’ pfos and is in network. But I’d prefer to see Dr Ebersole since he’s currently considered the expert.
That's basically what I do as well. When I first started diving trimix on the unit I was really annoyed because I was too stupid to realize that during the initial part of deco it was ridiculously hard to keep a high p02 due to offgassing helium so rapidly. When it finally dawned on me what was happening deco became alot less annoying. It's really odd to see as offgassing slows down how your loop contents stop dropping as rapidly. I think that was the oddest revelation for me going from OC to CC
it's a neat trick to know when deco is actually done as well. If the loop is still dropping rapidly then you probably shouldn't head up yet...
I had mine closed. Absolute game changer. 10/10 would recommend.
I'd been curious about the effect of off gassed nitrogen remaining in a CCR loop used for deco. If it accumulated enough to make the deco less effective, or if occasional venting was needed to keep the ppN2 down. Thanks. That you off gas enough helium to affect the physical volume of the loop is fascinating.
Taking just the nitrox case, if you are at a constant depth and your ppO2 is going down faster due to N2 off-gassing and you do not try to keep it high at say 1.4 but let it drop to say 1.2 by definition you've increased the ppN2 of the closed loop of gas you are using for deco and so decreased its effectiveness as you off-gas more and more N2 into it. How much, I do not know.I don't know that it's less effective, since as your p02 bleeds down you're just adding oxygen. Watching your counterlung expand and your p02 drop because you're offgassing helium still fascinates me on dives. If I jump back to Nitrox it's noticeable but to much less extent. With helium it's very very noticeable.
I had mine closed. Absolute game changer. 10/10 would recommend.
I'd somewhat often feel like doodoo after a deco dive. On some dives it would be extreme-doodoo feels. I was always overly concerned with the deco schedule, fiddlin' with this and that trying to figure out something that worked.A game changer how? From less risk of taking a hit, or something else? Just curious... Thanks.
Taking just the nitrox case, if you are at a constant depth and your ppO2 is going down faster due to N2 off-gassing and you do not try to keep it high at say 1.4 but let it drop to say 1.2 by definition you've increased the ppN2 of the closed loop of gas you are using for deco and so decreased its effectiveness as you off-gas more and more N2 into it. How much, I do not know.
ETA: I imagine it is less effective by the difference between 1.4 and 1.2 ppO2 on nitrox at that depth. And I mean less effective on time, not on the effective use of the O2 available in the cylinder. My original curiosity came from the case of grabbing an O2 rebreather because of omitted OC air/nitrox deco and hanging at 20' on it. Over time you fill the loop with more and more N2 if you never vent gas, making it less and less of a pure O2 deco and more breathing the same N2 you flushed from tissues.
Agreed. If you vent them, from the ascent or intentionally by exceeding feasible loop volume while striving to maintain a decent ppO2, despite increasing N2 in your loop.Those offgassed inerts don't stick around the whole time.