Nitrox - Is it "worth it"?

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I have been diving Enriched air/Nitrox, for most of my diving career. I also ended up in the chamber in Cozumel with about 475 dives under my belt, and no definitive reason as to why I ended up with skin benz type 2 with neurological involvement. I had 5 days of chamber treatments.

I now have a little over 700 dives under my belt, and I always recommend Nitrox to everyone.

When we go down to depth, our computers/dive tables, are basing calculations on theoretical numbers, these numbers came from young healthy individuals. When we are under the water, we don't have wires directly monitoring our nitrogen load.

All of our bodies off gas differently. As we age, our bodies are less efficient at releasing nitrogen, also bone density, scar tissue, fatty tissues, make nitrogen harder to release.

Diving enriched air reduces the chance of getting nitrogen narcosis. Clearly there is no guarantee.

In addition to the above, you can get more bottom time, shorter surface intervals, and you feel less tired. Personally, I don't use it to extend my bottom time. I use it as an additional precaution.
Were you on nitrox the day you got bent?
 
You just never know. For any given dive, it's possible that you'll be just fine on air and you'll be just fine with nitrox. In one sense it's a form of insurance. The only difference is that if you use nitrox and come out of the dive just fine, you'll never know if you could have used air instead.

Life is full of risks and rewards, and the cost of mitigating risk entirely depends on an individual's preferences. Which is why you'll get a wide variety of responses to your question. But the only one that matters is the one that you decide fits your personal risk-reward-cost profile.

(Personally, I nearly always use nitrox when available because I frequently dive with my 70-year old mother and the cost of nitrox is relatively trivial for both of us.)
But...for any given dive there is less chance of DCS with nitrox because for any given dive you have less nitrogen loading,
 
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And your post further reinforces what I was saying. Dive air or nitrox to the NDL and the nitrogen loading is the same. And the off gassing during ascent is the same as well.

Offgassing should be faster on nitrox, as the inspired PPN2 is lower. This is the theory behind accelerated deco on nitrox and O2 at appropriate depths.* So even though the saturation at the NDL might be the same, there is still a (small, for anyone diving recreational profiles) theoretical advantage to using nitrox.

* If I recall correctly, the difference is thought to be proportional to the ratio of the partial pressures. So on EA32, I'd expect offgassing to be 79/68 faster, about 16%. This makes no operational difference because the ascent speed and safety stop time should be the same on either air or nitrox, but your final inert gas loading on the surface should be lower on nitrox.
 
Offgassing should be faster on nitrox, as the inspired PPN2 is lower. This is the theory behind accelerated deco on nitrox and O2 at appropriate depths.* So even though the saturation at the NDL might be the same, there is still a (small, for anyone diving recreational profiles) theoretical advantage to using nitrox.

* If I recall correctly, the difference is thought to be proportional to the ratio of the partial pressures. So on EA32, I'd expect offgassing to be 79/68 faster, about 16%. This makes no operational difference because the ascent speed and safety stop time should be the same on either air or nitrox, but your final inert gas loading on the surface should be lower on nitrox.

That was a whole lot of typing to agree with what I said.
 
But...for any given dive there is less chance of DCS with nitrox because for any given dive you have less nitrogen loading,

True... but whether or not that results in any real benefit, we'll just never know. If you use nitrox on a dive and do not experience any DCS symptoms, you'll never know if you could have instead used air... and still experienced no DCS symptoms. Similarly, if you use air and you DO experience DCS symptoms, it's impossible to know if the symptoms would not have happened if you used nitrox instead.

So while the odds are in the favor of nitrox, whether or not it provides any real benefit on any particular dive is something we just can't know.
 
Sounds like the diving you'll be doing will be limited by your gas supply (i.e. shallower than 60 feet) and not by your NDL. Which means...

the cost to get nitrox certified for the long run (i.e. the rest of your diving future!) is well worth it

the cost of nitrox cert just for this trip is probably not worth it.

So... if you plan to dive in the future, even irregularly, invest in the nitrox class. Once you have it, you'll use it, even just occasionally. And you'll learn some interesting stuff in the class. And then you'll have the chance to use a nitrox tank a few times (you don't need it for every dive...) during your trip.

Even better, if you're switching back and forth from air to nitrox during your trip, you'll get a lot of practice at working the settings of your dive computer, maybe reading through the manual. There's a lot of secondary benefits to doing the nitrox class that are good for your diving experience in general.

This is the type of response (very helpful by the way) I've been getting from many people and what has made us decide to get the certification. I think based on the reasoning you provided it will serve us well on this upcoming trip and future trips! Thank you!
 
https://www.shearwater.com/products/perdix-ai/

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