A Question for Nitrox Mavens

[joewr]

Hi,

When dirt was still young and I was getting certed for EAN, the basic line was EAN allowed divers with good bottom times to extend their dives at a given depth by reducing the nitrogen content of the "air" source. However, a few days back, I stated something along those lines and was somewhat surprised to hear that folks now use Nitrox but dive with air tables (really air settings on their computers--I'm pretty sure most of them haven't dived using printed air tables ever!).


So, my question: is that what the dive cert agencies now teach: EAN using air settings to lessen the risk of DCS...as opposed to extending dive times? If so, when did they begin doing that?

Thanks...

joewr

 

[Splitlip]

I got my nitrox cert about 10 years ago. A friend got his 2 weeks ago. "Longer bottom time and shorter SI" is still goal. But certainly diving air tables is an option for a huge safety factor.

 

[mathauck0814]

I've always thought that the primary benefit of EAN was limiting your exposure to nitrogen. For nitrox or trimix blends, that's always been my goal - obviously you have to balance that against the risks inherent to pressurized O2, but I've never used EAN as a means to make air tables safer - they're already plenty conservative as they are!

 

[joewr]

I got my nitrox cert about 10 years ago. A friend got his 2 weeks ago. "Longer bottom time and shorter SI" is still goal. But certainly diving air tables is an option for a huge safety factor.

Hi,

So, that was what your friend was taught: use Nitrox with air settings as a safety factor? Of course, that would work, but I was curious if that what was being actively taught?

I am going to stop an LDS today and ask there, as well...

Thanks,

joewr

 

[RTee]

If you go through PADI EAN reference material, it does cover both aspects ...extended bottom time and additional conservatism if diving air NDL.

 

[joewr]

If you go through PADI EAN reference material, it does cover both aspects ...extended bottom time and additional conservatism if diving air NDL.

Hi and Thanks,

The "PADI reference material" I received during the Jurasic, was printed in the 80's. It does not, once, mention diving with air tables. Quite the opposite: it stresses the need to learn EAN tables.

So, I guess, I will Put Another Dollar In and get PADI's latest...

Thanks, again,

joewr...This space is still for lease, but you better hurry...three eager bidders are already chomping at the regulator mouthpiece...

 

[Splitlip]

Hi,

So, that was what your friend was taught: use Nitrox with air settings as a safety factor?


joewr

He was taught the same as I. Diving air tables was only discussed as one of the options/advantages of using oxygen enriched air.

 

[Mossman]

But certainly diving air tables is an option for a huge safety factor.

That's very debatable. Statistically, there's no demonstrated benefit.

 

[TMHeimer]

The "old" PADI manual says Incidents of DCS are basically no more or less whether using Air or Nitrox, unless you use Nitrox and follow the Air tables. Uhhh.... yeah that makes sense.

 

[Thalassamania]

You can take the "advantage" of EAN either way: keep the risk of DCS constant but extend your bottom time, or decrease your risk of DCS for a given time/depth exposure. I have been using EAN since the early 1980s in the later fashion.