Common reasons for diving nitrox

[BHB ScubaTroll]

Here is an example of why I use EAN.

EAN36 Dive Log
2 Dives on the second day

SI: 16:35
Dive 1:
BT: 79 min
MAX Depth: 54'
AVE Depth: 45'
Tank: HP133

SI: 0:39
Dive 2:
BT: 79 min
MAX Depth: 56'
AVE Depth: 45'
Tank: HP133
====
In both cases I surfaced with more than 1500 PSI in each tank. Why did I surface when I did?

This was a boat commercial boat dive.

My partner and I were the first in the water on both dives. I was last back on the boat on both dives.

I was down 20 min. longer than the last person on the boat. I saw no reason to hold everyone else up just because I could have stayed down for another hour or so without reaching any limits.
====
Why do I use nitrox? bwaaaahaaaahaaaa!

 

[amascuba]

It's my experience that Nitrox doesn't reduce the effects of narcosis. In fact some people say that elevated levels of oxygen are just as narcotic as nitrogen.

Feeling less tired after a dive or a day of diving? Personally I've never felt any noticible difference.

I'd agree to the first two choices of longer bottom times within the NDL and shorter surface intervals.

You're forgetting the best reason of all though. Getting to sport the green and yellow stickers on your tank that say "Nitrox"

 

[Quero]

I stand by my implied warning. If your dive op is going to require a specific bottom time and surface interval that works just as well with air, or if your dive buddy is going to bring you up with half a tank--well, dive air.

I'm in this situation frequently here--diving with new divers with ops that determine fixed bottom times--and I still prefer Nitrox. Diving Nitrox simply reduces my nitrogen loading, pure and simple. I don't mind coming up with half a tank of Nitrox in exchange for the added margin of safety.

So the only logical answer to the poll for me is the shorter SIT, but what I really mean by my vote is that by the end of the SIT I will have less residual nitrogen having dived Nitrox than if I had been diving air.

 

[andydiver06]

If I remember correctly minimum SI for any Nitrox Dives in 60 minutes ( PADi EANX course) .

 

[Matsya]

It would have been good if this had been a multiple choice poll. I dive nitrox for extended bottom time at times and shorter surface intervals at times. I know that there is no concrete evidence to say that it helps in feeling less tired but I personally feel a marked difference between diving air and nitrox. So yes I dive nitrox to feel less tired too.

 

[BarryNL]

Everything but the third option. Oxygen is almost as narcosic (is that a word?) as nitrogen. Sure the last one hasn't been proven, but I don't need a book when I can feel it. Even if it's placebo, that's fine too (sounds like a good opportunity for a double-blind test).

Personally, I find nitrox far more narcotic. I don't really get affected much by narcosis on air (I'm one of those who did the task faster underwater on the AOW skill test) but when I'm diving 32% I can feel it from around 20m.

 

[Quero]

If I remember correctly minimum SI for any Nitrox Dives in 60 minutes ( PADi EANX course) .

Hmm. I don't doubt that somebody gave you this as a rule/guideline, but as far as PADI EANx table rules go, you may be mixing it up with something else--possibly the rule that if you end your dive in PG W or X, the minimum SI is one hour. But that is true for dives on air as well, not just Nitrox.

 

[BigTuna]

Dive nitrox, pretend you're on air.

 

[Damselfish]

Hmm. I don't doubt that somebody gave you this as a rule/guideline, but as far as PADI EANx table rules go, you may be mixing it up with something else--possibly the rule that if you end your dive in PG W or X, the minimum SI is one hour. But that is true for dives on air as well, not just Nitrox.

The one hour rule was definitely in the PADI Nitrox class when I took it. Not that I've ever seen anyone worry about following it.

 

[Meister481]

I'm that guy, the one who always has 12-1500 psi left in his tank when he gets on the boat. I rarely use nitrox because I only have 1 buddy with a SAC rate low enough to allow me to hit the NDL in most places.

My main use of Nitrox is when I go wreck diving in Lake Michigan. The extra few minutes of bottom time are huge when you've only got 10-15 minutes of BT to begin with. Nitrox gives you some extra safety margin in the frigid waters at 100-130 ft where you decend too hot from the struggle with gear at the surface and cool rapidly at depth. This can be a recipe for dci if you are not careful on your ascent and subsequent safety stop.