No, because its about EAD not NDL.
Changing your computer to a more conservative setting will reduce the NDL time (or in the case of gradient factors, it will alter the decompression profile in a dive with mandatory decompression stops, i.e., depth of first deco stop and length of final deco stop).
Using enriched air Nitrox results in a "shallower" equivalent air depth "EAD". In other words, in terms of inert gas (nitrogen) loading, an 80-foot dive with air is equivalent to a 65-foot dive with EAN32 or a 59-foot dive with EAN36.
So the reason your buddy feels better with Nitrox than air is because he has taken up less inert gas and, therefore, has fewer micro bubbles coursing around after the dive, a/k/a "silent bubbles". An excess of silent bubbles increases post dive fatigue.
Slowing the ascent rate and/or doing longer and/or multiple safety stops would also reduce micro bubbles as long as it doesn't come at the cost of further on-gassing of slow tissues.
You changed your post a lot (which is fine).
For recreational no-decompression-stop diving, using Nitrox could reduce post dive fatigue, but so can simply reducing your depth and/or time exposure. Changing your computer to a more conservative setting does not serve that purpose.
I'm not saying not to use nitrox, I'm saying it would be better to understand why you (not you, any diver) are feeling tired. And I said "it's not just about changing your computer".
I really don’t understand how nitrox is the most misunderstood thing in diving. All I can figure is crappy open water training that didn’t lay a proper foundation followed by a crappy nitrox course that didn’t fully explain how things work.
1. Adjusting conservatism in decompression models is not the same as adjusting inert gas intake.
2. Nitrox reduces the amount of inert gas that is brought into the tissue compartments, which lessens the amount of inert gas that must be dispelled from said tissues.
3. There are no peer reviewed journals showing nitrox has an appreciable impact on how one feels post dive….and yet literally everyone agrees they feel better on nitrox (including young 20 year olds lol).
4. Relating to how one feels post dive, it would stand to reason that if you ongas less inert gas and therefore offgas less inert gas you are putting less of a strain on your body…
So do you dive nitrox on every dive?
5. As to the misinformation in this post about “moving too fast” or ascending “too fast” and needing to slow down the dive, I’d encourage that person to research more before posting.
This I don't understand? It's been proven time and time again people move too fast, especially in the last 20'. Why would telling someone to slow that down and look at other aspects of their diving be a bad thing?
You’re wrong.
There is a big difference between someone feeling BAD and someone feeling tired and/or more fatigued. The fact that you’d even suggest that you’d rather “go into deco” on air rather than using nitrox is self evident that you have no idea what you’re talking about.
You’re literally saying you’d rather intentionally on-gas more Inert gas at depth as a way to “be more conservative” rather than to literally use a nitrox mix that’s fundamentally designed to keep a person from ongassing more inert gas.
You need to seriously hit the books on this subject. You are propagating some seriously false info. Your friend is absolutely right and you are absolutely wrong. Why in the world do you think that nitrox is used to the degree it is in technical diving? Why is helium used in trimix, why is inert gas intake so important and managing inert gas intake so important.
Please, read up on this before trying to convince your friend to do dangerous and incorrect things.
I never said BAD (which to me would convey some form of DCS). I said tired / bad meaning fatigued / worn out. And I'm not saying don't use nitrox, I think nitrox is a great tool. I'm saying I think one should figure out what it is about their diving that causes them to feel tired in the 1st place before just throwing a different gas at it. Sure nitrox will probably work, but let's start with what gf's do you dive, how fast do you think you ascend? Hell, let's look at some post dive analysis and see if we can't figure this out.
My point is you don't have to feel like crap diving air. You really shouldn't. I'm not saying "never dive nitrox".
I asked you what you meant by "same result" and then you just repeated "same result".
I still don't know what your actual question is.
So far I have your questio0n/assertion as "If you dive conservatively it's the same as diving nitrox". But the agreement/rebuttal of that completely depends on what you mean by "the same".
To me if the same diver is diving in a way that air makes them tired then they should probably look at their diving habits vs just what type of gas they use?
Yeah pretty much agree, plus casually extending an air dive into deco, (rather than use nitrox to avoid it) is ridiculous from a safety standpoint. Going into required deco complicates the dive immensely, increases your vulnerability to failures and problems and even makes you a less capable buddy should an emergency occur. I'm not so sure how the OP got so far off track on this.
I never said avoid nitrox. How is using air and going into 15 min of deco any different than using nitrox and going into 15 min of deco?? Obviously the dive times have changed, but how is the end result any different? Somehow though I'm magically a safer diver with 15 min deco obligation and a different gas in my tank?
Which of these dives is more conservative.
20 minutes at 100ft, with a 30fpm ascent to the surface with the GF of 100/100
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or 100ft for 20min with 70/70 and a 10 minute stop at 20ft
View attachment 832309
Does the 70/70 dive have "required deco" or is the 100/100 dive "omitted deco"
You can move these numbers around to make your deco whatever you want it to be.
This is a great illustration of my point. If you dive 100/100 and just throw nitrox at it and continue to dive the same way I don't think that's really a great answer. It feels (to me) more like a band-aid.
Listen, I will dive air, I will dive nitrox. I think nitrox is a great tool for what it is. I use it for the dives that I plan that I think it's warranted. It just depends. Do I think it's needed in a pool, or a 20' dive to find something for someone at the dock? No. Do I think it's needed for a week long trip diving to 60' 100 times to look at fish,.... of course. But I wouldn't use it just because I felt tired. I would take a hard look at why I feel tired in the 1st place and try to make some changes, and then maybe also incorporate nitrox.
Maybe I should have stated it more clearly. We were on a 15' dive on Sat, buddy said his buddy always dives nitrox, no matter what the depth / dive is. He said he
always felt tired on air. To me this says something else is going on. My argument was that if you change the way you dive on air I bet you would feel much better.
I agree nitrox is a better gas (that was never my argument). Understanding why you get tired on air is just a better place to start.
