Nitrox 32 first dive, air second dive?

[rgdiver1]

I believe Meridiano charges an additional $12 per tank for nitrox. Also I didn't see the tanks analyzed. You have to accept that the tank actually has the marked mix - or not.

 

[tursiops]

Thanks for the replies so far.
Correct. We're talking $70 over 7 days.
The question was:
Following typical Cozumel dive profiles and having done dive 1 on EAN32, will I get anywhere near NDL's on dive 2 diving EAN21?
When diving 2 consecutive tanks of EAN21 we got closer than I liked, so that's why I'm asking.
I'm assuming that the next morning we're all cleared and ready to start loading from scratch again.

You need to learn how to answer this question yourself, using your computer or software. I'm not trying to be snarky, just pointing out it is kind of basic dive planning.

 

[Lorenzoid]

For the love of Triton!--will somebody please just plug this into a planner/computer for keesmon?

 

[nodakdive]

I have a very conservative computer (Suunto Mosquito) and dive air on the first, nitrox 36 on the second. My understanding is that this is pretty much common practice if you're diving air and nitrox using 80s. As first dives are often on walls, and/or deeper, using air gives you more max depth in the case of an emergency. As many/most of the second dives are more shallow, and are usually over a hard floor, you don't run into the MOD issue. Also, as that floor is usually 70 feet or less, if you're paying for 32, you'd might as well use 36.

I do 4 and 5 dives a day, regularly, using 80s, and I don't run out of NDL. Air on the 1st and 3rd tanks, Nitrox 36 on 2nd and 4ths. If I was using 120 cubic foot tanks, I'd likely be diving Aldora's method as described above.

 

[keesmon]

Depending on your dive op the other divers might be on air. If your are following the group you will be within the ndl. Nitrox would be added safety factor for yourself.

May vary depending on operator[/QUOTE

You need to learn how to answer this question yourself, using your computer or software. I'm not trying to be snarky, just pointing out it is kind of basic dive planning.

Thank you Tursiops.
I have put it into the planner, using last years dives that got me closer to NDL than I wanted, and have done the equivalent planning if I had used EAN32 on the first dive. Diving EAN21 on the second dive seems to be OK.
My question is:
What do other divers (Cozumel Nitrox certified veterans diving AL80's) do for their two dives?
This question I cannot ask myself. I am simply asking for the collective experience of the regulars to Cozumel. Thank you

 

[nodakdive]

I believe Meridiano charges an additional $12 per tank for nitrox. Also I didn't see the tanks analyzed. You have to accept that the tank actually has the marked mix - or not.

The dive shop I use, and I think this is pretty common among the shops, has an analyzer on the boat if anyone is diving nitrox.

 

[nodakdive]

Thank you Tursiops.
I have put it into the planner, using last years dives that got me closer to NDL than I wanted, and have done the equivalent planning if I had used EAN32 on the first dive. Diving EAN21 on the second dive seems to be OK.
My question is:
What do other divers (Cozumel Nitrox certified veterans diving AL80's) do for their two dives?
This question I cannot ask myself. I am simply asking for the collective experience of the regulars to Cozumel. Thank you

I should have added, "...pretty much common practice, on Cozumel, if you're diving air..."

 

[keesmon]

I have a very conservative computer (Suunto Mosquito) and dive air on the first, nitrox 36 on the second. My understanding is that this is pretty much common practice if you're diving air and nitrox using 80s. As first dives are often on walls, and/or deeper, using air gives you more max depth in the case of an emergency. As many/most of the second dives are more shallow, and are usually over a hard floor, you don't run into the MOD issue. Also, as that floor is usually 70 feet or less, if you're paying for 32, you'd might as well use 36.

I do 4 and 5 dives a day, regularly, using 80s, and I don't run out of NDL. Air on the 1st and 3rd tanks, Nitrox 36 on 2nd and 4ths. If I was using 120 cubic foot tanks, I'd likely be diving Aldora's method as described above.

Interesting. The opposite approach of what I was thinking. Let me mull that one over. I like the idea of the added depth safety for dive 1. I have almost run into NDL's on the first dive on air though, and that's using an Oceanic Computer.

 

[tursiops]

For the love of Triton!--will somebody please just plug this into a planner/computer for keesmon?

No, but I'd be happy to verify/discuss whatever result he comes up if he were to try and do it himself.
I don't think we ought to spoon-feed such basic info.

Thank you Tursiops.
I have put it into the planner, using last years dives that got me closer to NDL than I wanted, and have done the equivalent planning if I had used EAN32 on the first dive. Diving EAN21 on the second dive seems to be OK.
My question is:
What do other divers (Cozumel Nitrox certified veterans diving AL80's) do for their two dives?
This question I cannot ask myself. I am simply asking for the collective experience of the regulars to Cozumel. Thank you

OK, good for you. You are already hinting at the point: if you use air on the first dive, you get awfully close to your NDL. Why do that? And air on the 2nd dive is probably OK, regardless of the first dive; but why do that? Why not give yourself a cushion in your Nitrogen uptake so you do not need to be concerned about NDLs? Just use Nitrox on the first dive, and better yet on both.

 

[flyboy08]

ProDive.........FREE NITROX! Hello?