On Jul 23, 7:21*pm, mail box > wrote:
> On 7/22/2008 4:00 PM, wrote:
>
> > Spent the last day or so reviewing all the previous posts on the use
> > of inert gases for top-up, and wine transfer.
>
> > I understand the caveats that Tom S raised about a false sense of
> > security.
>
> My newsreader (Thunderbird) seems to be unable to search on sender. *
> * When I try to search I get an error "NNTP: aborted by user" error
> message and no results. And so I can not find the posts by Tom S you
> refer to. *So at the risk of repeating old content, my understanding on
> bottled gasses was that the greatest risk was concerning the
> quality/purity of the gas, as anything other than medical grade carried
> the risk of all kinds of contaminants including oils and other
> substances being contained in the gas. *Is this a realistic concern, and
> if so how have you protected your wine against foreign substances being
> introduced via bottles gasses?
>
> Cheers,
> Ken
Hmm, you bring up a point i had not considered deeply.

A quick google seems to indicate that TIG welding uses pure argon at
99.999% purity.

"In the Tungsten Inert Gas welding (TIG) process, the gases used as
back
shielding gases obtainable from the gas supplier ere usually pure
argon
having a purity which is at least equal to 99.999% (the impurities
content
is below 10 ppm)."

http://www.patentstorm.us/patents/53...scription.html

I am not an authority on this.