First dive with EANx32 second with air.....

[Icarusflies]

Hello There;

I am diving this Sunday with my new HP Steel Tank. This tank is filled with ENAx 32. My second dive after the SI will be with a standard AL tank filled with air. I have reviewed my NITROX book and I see nothing saying that I can not do a second dive with air after a NITROX dive but I wanted to ask you guys so I am sure.

Thanks

 

[HowardE]

Set your computer to 21% and go.

You should be more concerned with the difference in weight you'll need from the steel 100 to the AL80. Be prepared to add 4 lbs to your weight belt.

 

[TheRedHead]

There's no reason why you can't. I've mixed the two, but it has usually been the first dive on air and the 2nd on Nitrox.

 

[Wayward Son]

You can do it in that order, but my instructor advised us to do the 1st dive on air & the 2nd on nitrox. The reason being is that you'll see more benefit from the nitrox on the 2nd dive. Just be sure to program your computer correctly and/or plan it correctly using tables.

 

[wedivebc]

If you subcribe to the deepest dive first philosophy then it makes more sense to do air first then nitrox. In fact you could do both dives to the same depth and have the second dive with a shallower EAD and still follow that rule.

 

[HowardE]

If I was on a typical S Florida dive trip... it would probably be a wreck and a reef. The wrecks are typically in the 70-100 FSW range, and the reefs are in the 30-50 FSW range. I would do the nitrox on the 1st dive, although I would probably opt for a richer mix, to further extend my BT...

 

[The Kraken]

Make sure that the depth of your second dive is less than the EAD of your first dive if you want to follow the "deepest first" plan.

Case in point first dive 90' on EAN32, second dive 80' of "air".

EAD (or "nitrogen depth) of EAN32 for a 90' dive is 73' . . . and, of course, the nitrogen depth of the second dive is 80'.

the K

 

[jpcpat]

Dan has dropped the deepest dive first rule, though it can't hurt, and PADI still teaches it.

As for the switch from EanX to air, don't sweat it. PG's among tables are equivalent, and your computer will handle it IF you remember to switch the mixes.

 

[Skinsfan1311]

....why not drop the extra couple of bucks and do the nitrox for both dives?

 

[HowardE]

....why not drop the extra couple of bucks and do the nitrox for both dives?

At Fill Express... where he filled his tanks... air and nitrox cost the same