Ease of deco from He based gases...

[Dr Deco]

Dear DivingDoc:

As always, drug delivery by the blood stream is a difficulty when that system is embolized. It will be a while before we see a treatment for gas emboli or blood clots with injectables. Clot lysing from proximal to distal is a different matter.

The helium encapsulation material was very interesting. Thank you for sending it my way.

Dr Deco :doctor:

 

[MikeFerrara]

Braunbehrens once bubbled...
Maybe then we'll finally get to see if those oxygen masks really work.

Speaking of which, I took my O2 analyser on a plane once. Fascinating. Read 16% the whole way. No wonder people get sick on long plane rides. Of course this is a PO2 reading, really, not a percentage reading, since it was calibrated at ground level.

That sounds about right. What do they presurize the cabin to? 8000 ft or so?

 

[BIGJC]

the consensus here is that helium based mixes are atleast as easy as nitrogen to decompress from and that they tend to be easier given the right circumstances....

My question ,as always, is if using these gases improves safety and it seems like a "YES" in this discussion...

am I right or what??

=-)

 

[Dr Deco]

BIGJC:

Yes, helium is safe. The major problem is getting the mix (and the cost). If you are just a recreational scuba diver, there is really no advantage over air for shallow dives.

Dr Deco :doctor:

 

[rcohn]

Please correct me if I'm wrong, but my understanding is the He mixes are less tolerant of diver mistakes than N2 mixes. If you overshoot your stop depth for some reason and need to descend you would be better off with more slowly diffusing N2 than He. If my understanding is correct, He might not be the best choice for a diver who is new to decompression diving.

Ralph

 

[Braunbehrens]

Dr Deco once bubbled...
BIGJC:

Yes, helium is safe. The major problem is getting the mix (and the cost). If you are just a recreational scuba diver, there is really no advantage over air for shallow dives.

Dr Deco :doctor:

I know a couple who used ASL under water (sign language for the deaf). They say that they can tell the difference between the surface and 40 feet in terms of impairment.

 

[Dr Deco]

Dear Readers:

I guess what I had in mind (notice the back-peddling here ) was that helium was safe, but it was not safer than, nor superior to, nitrogen (air) where narcosis is not a problem. This would be for shallow dives.

Gas bubble grow with helium is said to be fast, and that is attributed to the rapid diffusion of the helium molecule in water.

Dr Deco :doctor: