28% Nitrox

[k ellis]

28% is not in the PADI dive tables bacause that puts a diver beyond the 130' max depth for a rec diver

Using this logic it would also go to say that plain old good air would not be in the tables either as it is only 21 percent. This would have a deeper MOD then 28 percent.

Even if they did make a table for it they would simply do as they did with air and end the chart at 130 as PADI does not recommend a rec diver go deeper then 130 feet.

Ive seen various percentages of nitrox used even as low ar 25 percent

 

[Centrals]

Ive seen various percentages of nitrox used even as low ar 25 percent

Started with 32% on a twin set and top up with air after the dive and eventually came down to 24%. After that I just treated it as EAN 21. BTY, have to remember to set the computer accordingly.
I still have a pile of IANTD soft tables in my closet. The soft air table is very easy to keep in the pocket.

 

[Belce]

28% nitrox and 100 cubic foot tank makes for a great cloud sponge dive here within ndl. It is a sponge worthy mix.

 

[String]

I'm still planning my dives at 1.6 so 32% is OK for 40m. I keep forgetting that most of the world has moved past that.

..in that case any dive between 40m and 47m then if you dont want to overdo the p O2s.

28% has a perfectly valid use - it allows you deeper than 32% for whatever partial pressure you choose.

 

[String]

True, but only if you always fill your tanks with a specific dive in mind.

I always keep my tanks filled with 28%. Since the MOD is about my own depth limit as a non-deco diver, and since I don't always know ahead of time if I might be diving on any given weekend or which wreck I will be doing, I get a little extra NDL for whatever dive I do. With 28%, I don't have an issue if we go to a wreck with good diving below the MOD of a richer gas.

Similar here. I do 28% or even air. We rarely if ever can guarantee what site we'll be diving until the boat is on the water and en-route. If ive got 32% and it turns out conditions on that wreck aren't great or conditions from reports on a 40m wreck 1 mile away are exceptional im stuck and can't dive it.
With 28% i can go to 40m or so as a maximum which gives me a lot more flexibility than 32%.
...then again air offers me more flexibility again and is half the price!

 

[oly5050user]

Similar here. I do 28% or even air. We rarely if ever can guarantee what site we'll be diving until the boat is on the water and en-route. If ive got 32% and it turns out conditions on that wreck aren't great or conditions from reports on a 40m wreck 1 mile away are exceptional im stuck and can't dive it.
With 28% i can go to 40m or so as a maximum which gives me a lot more flexibility than 32%.
...then again air offers me more flexibility again and is half the price!

Same issues here in the northeast USA..can plan out dive using 28% simply using dive computer or EAD table and a air RDP...28% is a very common mix here.

 

[redacted]

Same issues here in the northeast USA..can plan out dive using 28% simply using dive computer or EAD table and a air RDP...28% is a very common mix here.

Which agencies provide EAD tables for 28%? My NOAA Diving Manual does provide an EAD table covering 28% through 40% as well as the instructions for calculating EAD. My PADI EAD table dated 1995 only covers 30% through 40%. I believe I recall the PADI manual providing calculation instructions but I can see where some might think those calculations might be a lot of work and subject to errors.

 

[Blackwood]

Which agencies provide EAD tables for 28%?

IANTD's has it (top row, third from the right).

As I mentioned earlier, they also have a 28% dive table.

 

[String]

My PADI EAD table dated 1995 only covers 30% through 40%. I believe I recall the PADI manual providing calculation instructions but I can see where some might think those calculations might be a lot of work and subject to errors.

The calculation was mandatory (now its optional). EAD is perfectly usable on the PADI tables (there are some tables EAD wont work on but padi is fine). You're likely to get less error as you havent got all the rounding shoved into the tables. Admittedly less error on something as blurred and non-precise as dive tables is relatively meaningless anyway.

 

[Jim Lapenta]

I believe NAUI Tech has tables for that as well. 28% is also a good Lake Erie mix. For my own reasons of conservatism I use a max of 1.3 working and have v planner set for that, with a 1.6 for deco. In my Intro and Helitrox classes we mixed for the bottom as a buffer. If I were doing the Grove again I'd want a mix for 135 -140, Duane 120. and for me that would be 26% Would most likely not go there but hey. If not using air that is. I don't mind a little deco.