Posted by Marc Hall on December 04, 2001 at 14:24:21:
In Reply to: Thanks - strange that there are none in L.A. or Valley posted by bbc on December 04, 2001 at 08:09:40:
I believe a number of people (shop owners) feel that a membrane is not a cost effective way to provide Nitrox.
There is the capital cost of the membrane which
is fairly steep. The membrane also needs a supply
of clean air at approx 200 psi which at least
half becomes nitrogen enriched waste air.
To generate the 200 psi air you either need a seperate low pressure compresssor or feed it
from your air storage banks that are filled by
your normal scuba compressor. You basically
need to compress 3X the volume of gas to
generate a Nitrox fill which results in an increased energy bill.
A fill station could premix Nitrox by either
partial pressure mixing or continous
blending, bank it and provide Nitrox fills w/o ever putting pure O2 thru your valves.
EE Adventure Store in High Springs, FL is selling
or has sold its membrane. I was told that it
was less expensive for them to mix from a pure
O2 supply.
Dive Excursions in Luraville, Florida sells a
lot of Nitrox (20,000 cft storage banks) and
banks Nitrox 34. As far as I could tell they
did not require O2 clean tanks for Nitrox 32/34
fills.
Marc Hall
svcfish@yahoo.com