On 2/24/21 2:03 AM, Darryl Ramm wrote:
On Tuesday, February 23, 2021 at 9:47:53 PM UTC-8, wrote:
At the Cowley wave camps, there's the odd day when record attempts are made to 30,000+ It gets really cold up there as in -30C - actually surface temperature at night a week or so ago.

My welding supplier advises ABO for that kind of height and temperature, and I'm inclined to believe him. But the turnaround time for ABO cylinders is really slow here.

Your welding supplier is confused. **there is no difference** This is the perennial noise that comes up on r.a.s every few years. All the O2 in these uses comes from cryogenic fractional distillation. The cyrogenic process freezes out all moisture. All those cylinders are filled from the same liquid oxygen source. Oxygen distribution systems are inherently dry. If they had moisture in them we'd have a boat load of safety issues in handling and distribution.


Medical oxygen is frequently humidified on purpose, but it's done
outside of of the high-pressure cylinder. Maybe that's the confusion.

Concerning Parowan, years ago I was there with a cylinder and regulator
rated for 3000 psi, so I asked for the high pressure fillup.

Worked fine until a few thousand feet in the air, the regulator failed
and blew apart the low-pressure line that started whipping around the
cockpit. Had visions of being another Richard Pryor until I managed to
stick the tubing out the window, then get the oxygen shut off.

Sometimes fixing one problem creates a bigger one in its place.

-Dave