Triox for the masses

[RTodd]

I see. So the biggest safety factor is the lack of immediate access to the surface with He as compared to EAN or air. Although all DIR dives are "deco dives" He imposes tighter restrictions on ascent rate which basically requires you have the same buoyancy and ascent skills as a true deco diver.Do I have this right?

If so, I can see the need for additional training before cutting people loose with the gas. My Dir-F experience is clearer now that I can see where it is headed. Thanks for the help guys. I guess I will be patient for a while.

The ascent profiles we use for nitrox on a "minimum deco" dive basically mimic what would also be used with Helium for the same bottom time. The advantage of Helium is that when it is in the mix these profiles produce better decompression and you surface "cleaner." The flip side is that these ascent practices are necessary with Helium in order to exit safely whereas they have less benefit with nitrox so a straight shot to 15' or the surface (all that your typical diver is capable of/ knows how to do) is not as big of a deal with nitrox.

 

[Wally1716]

[/b]Why are they keeping it from me?
Does anybody have a good answer?

.
Simpy...for the same reason they kept Nitrox away till you
got certified on EANx. There are some concerns you should
know about and training is a simple way to ascertain that
you understand them (maybe ?). Different Deco Tables with
several options now available, body's thermal regulation,
ascent rate changes, physiology of CO2 retention and
narcosis are some of the topics you should dwell before
venturing out on Helium.

Of course, there is no LAW that stops you from doing mix.
But if you had a fill station, you wouldn't want to fill someone's
tank and be linked to the possibility of an incident because
they just "did know..."

For the IANTD Recreational Trimix your pre-requisites are only
Advanced OW and Basic Nitrox...and you get your gas.

 

[mocrumbo]

Anybody have a table of the oil:gas partition coefficients for N2, CO2, O2? How about blood:gas while you're at it??

Thanks!