First Nitrox Dives

[nereas]

What's the advantage of nitrox? I'm going on one nitrox dive (out of 6 dives) when I visit Islamorada next month and want to be prepared.

For dives to 50 ft or shallower there is not much if any benefit to nitrox.

It is in the range of 50 to 100 ft that nitrox is the best mix, particularly EAN36, because you lower your equivalent depth with the lower fraction of the N2 in the mix.

In other words, you are diving deeper, but it is as if you were diving shallower, as far as nitrogen loading is concerned.

Since nitrogen loading is the major contributor to DCS (bends), less is better for you.

 

[nereas]

Extended NDL's or shortened surface intervals.

the K

Kraken is precisely right. This is the resultant manifestation of the primary benefit to you, being extended NDL times on your first dives of the day, shortened surface intervals, or more efficient surface intervals of the same length (such as 1 hour), and extended NDL times on your repetitive dives as well.

This is because the models that compute these NDL times and surface intervals assume less N2 loading in the physics of their computational algorithms.

The benefit, itself, theoretically, from what we believe ("know") about physics is less N2 loading.

 

[nereas]

Anytime I plan to go to a resort or on a live-aboard, I always check first to see if they have nitrox. If they do not, then I scratch them from my list.

 

[highdesert]

I didin't feel any different (I.E tired etc..) after the dives.

It would probably be hard to notice any difference in your "tired level" after just two dives on Nitrox. If you go on a week long trip doing 4-5 dives a day on nitrox as opposed to on air, there is a much greater likelihood you would notice a difference. I guess not everyone does; I'm one who does notice it. Could just be body type, metabolism, etc.

 

[Thalassamania]

Not only this, but you also dissolve more O2 into your blood plasma, due to the higher ppO2 (partial pressure). I suspect that the energization factor has more to do with the dissolved O2 than the lower amount of N2. But who knows? It could be due to both.

I do feel the rush afterwards. It makes me feel like Superman. For an old man, like me, this is a very good thing!

Since oxygen transport is active rather than passive, and active transport on the hemoglobin is so much greater than the dissolved oxygen in the plasma, there is very little change in the oxygen carried in your blood as a result using NITROX. That's one possible explanation that we have to do without.

Bill Hamilton asked Parker Turner to elaborate on a cave diver "feeling better". Parker responded that the people he worked with do a couple hundred decompression dives per year per person. Based on personal experience, they have physically been feeling a lot better using the Royal Navy or the DCIEM tables, which they are relating to the fact that they are stopping deeper or sooner. The Royal Navy tables will have times that are similar to the US Navy tables, but they'll have you take stops at 20 fsw and 10 fsw. The Brits will have you take part of it sooner or at a deeper point. With two divers, each using a different table, the diver performing the shallower stop seems to have more problems typical of a subclinical hit, feeling tired or not feeling well after the dive. The divers on the Royal Navy tables feel a lot better. It seems to me that the DCs bring divers up for decompression at much shallower depths.

 

[nereas]

Since oxygen transport is active rather than passive, and active transport on the hemoglobin is so much greater than the dissolved oxygen in the plasma, there is very little change in the oxygen carried in your blood as a result using NITROX. That's one possible explanation that we have to do without.

I have also heard this theory, yes. It may very well be true. I also have to believe that the dissolving of the O2 into the blood plasma can provide a benefit as well. It seems probable that the hemoglobin effect is the greater of the two yes. I can agree with you on most of that.