Nitrox decision to make

[donnad]

ok, going to little cayman next month. will be diving 3 dives per day for five days with a night dive thrown in there somewhere also. you pay $12 per tank for nitrox down there, cause they have to bring it over from grand cayman i believe.........so........so as not to spend an extra $180 each (my and hubby)...to dive all nitrox.......would you dive the first dive of the day (and therefore the deepest), and the other 2 dives per day on air, or vice versa, or what are your thoughts and why? thanks!!

 

[scubajcf]

What is your dive plan for the first dive?
Second and third dives?
SAC Rates?

 

[BarryNL]

I'd be tempted to use nitrox for the longest dives. If you're doing multi-day diving it's the slowest tissues which theoretically become problematic. These tissues take up nitrogen more in long shallow dives than short deep ones. So, if you're basically diving air profiles but want nitrox for extra padding I' d use it for the long shallow dives.

On the other hand, if you can get more bottom time on the deep dives using nitrox then I would say that's a real benefit rather than the slight theoretical benefit of reduced multi-day loading.

So, better 30m for 30 mins on nitrox than 30m for 20 mins on air. But better 90 mins at 10m on nitrox than 20 mins at 30m on air.

 

[DA Aquamaster]

It depends also on the dive profiles. If you are gas limited rather than deco limited on your dives, there is not much advantage to nitrox. However, you are diving 3 dives per day for 5 days with a night dive thrown in somewhere. That is pretty aggressive and more than one diver has ended up with an "unwarranted" DCS hit as tables and computers are just not designed for that type of aggressive multi-dive, multi-day series of dives.

In the whole scheme of things, $180 for nitrox on all the dives and either more bottom time and/or more safety is not much to pay. Its' cheap insurance. Doing one dive per day on air does nto make much sense either as you are only saving $60.00 on the trip.

 

[ucfdiver]

I would always dive the 32% and do the deep stops for safety. $180 is a LOT cheaper than a DCS hit and chamber ride.

 

[donnad]

it would be $360 for the two of us..plus another $24 for the night dive.......but like you said.....much cheaper than the hit and the ride i was already planning on telling hubby i want to do deep stops. i don't know the profiles we'll be doing........will be in a group and i'm sure the first dive of the day will be deep/wall, as little cayman is famous for the wall diving........followed by another dive.........probably to 60 or 70 (i'm guessing here)........then back to shore for lunch break. and a third dive in the afternoon. then a night dive on one of the nights. i know they just say it's anecdotal......but last summer we went to saba and did 3 dives, but only 2 days in a row.....but still.........we claim that we did not feel as tired as we would have on air......just as a little side benefit.

 

[fppf]

Who are you diving with? There are only a few ops there?

We paid $10 a tank for Nitrox at Little Cayman Beach Resort/Reef Divers. They do not ship it in from Grand Cayman, most places that far out will have a membrane system that makes it from air.

We dove all week on 32, first dive was max 100 feet for 50 mins, second dive was max 60 feet for 60 minutes, thrid dive was max 60 feet for 60 minutes. We did not go to max depth all week, we did go max time though.

 

[scubajcf]

Deep is a pretty subjective term in Scuba.

Assuming that your SAC/RMV aren't excessive and it doesn't sound like you will be much deeper than 120 feet (check your MODs), I would probably dive 32% across the board. Maybe 36% on the third or night dive (depending on dive plan). When you look at the bottom time differential and the extra conservatism in your dive profile (compared to air NDLs), it is a value at $180 per person.

jcf

 

[Rhone Man]

I think if you are doing a long day's diving, the big upside to Nitrox is that you still have energy to party during the evening. Otherwise I usually find myself in bed by 9.30 on my holiday. Not sure what happens if you only use Nitrox for 1 of your 3 dives though...

 

[diver 85]

ok, going to little cayman next month. will be diving 3 dives per day for five days with a night dive thrown in there somewhere also. you pay $12 per tank for nitrox down there, cause they have to bring it over from grand cayman i believe.........so........so as not to spend an extra $180 each (my and hubby)...to dive all nitrox.......would you dive the first dive of the day (and therefore the deepest), and the other 2 dives per day on air, or vice versa, or what are your thoughts and why? thanks!!

Where are you staying???......we were there last summer & stayed & dove with LCBR....Their profile is 1st dive of the day max 100' & all other dives 70'(I believe these are correct----would have to check my log now)...Anyway, it did not pay to do nitrox......All diving with them is very EASY diving(vallet diving if you want to call it---my wife enjoyed that alot).....Personally, I would not spend the bucks on it.......I guess some were using nitrox but our group of 4 to 5 divers(all airers) were last back on the boat.......