On Jul 12, 9:11*pm, Darryl Ramm wrote:

So can we bury this one please?

Darryl

You may have to talk to someone at FAA. The link provided by the OP
includes this:

"Aviator’s
oxygen must meet certain standards to ensure that it is safe to be
taken to altitude. Only
aviator’s-grade breathing oxygen meets this specification. Neither
medical grade nor
industrial grade oxygen is safe to substitute because they do not meet
the same stringent
standards as ABO."

Of course it's been said many times in many places that this just
isn't true but FAA does seem to want to keep up the illusion. Maybe
their concern is that someone will top off with some other gas, such
as nitrogen which is available at many FBOs, if they don't insist on
ABO labeling.

Andy