Posted by NickD (24.240.212.148) on April 14, 2001 at 08:32:35:
In Reply to: Oxygen and airlines posted by Dennis O'Connor on April 14, 2001 at 04:38:39:
A constant problem in shipping liquidified gases, with a tank internal pressure of say 1,200 psi the difference between atmospheric pressure and a plane at even 45,000 feet altitude is only about 14 psi maximum, so keeping temperature constant this equates from a tank pressure of 1,200 to 1,214 psi, an insignificant change. The major culprit is temperature, as doubling the temperature in a constant volume of a tank can double the pressure, but the temperature reference is absolute zero on this scale, a small proportion when say increasing the temperature from 10 to 20 degrees F which is hardly doubling the temperature based on absolute zero at -459.69 F. However O2 tanks should be kept below 125F due to industrial ratings, never leave tanks inside a car where temps can exceed 180 F in the hot sun.
O2 is not combustible pe sa, but makes surrounding objects more combustible, the percentage of O2 can vary from 16-20% in an airliner, and if you consider the mass air volume of an airliner to an O2 tank, the percentages of increase would be negligible.
While that airliner is also carrying O2 tanks, the major factor is that your tank is not their tank and this prejudice also extends to many welding supply companies that would refuse to fill your tank, even though new and certified, it's not their rusty old tank, using logic and reasoning gets you nowhere so I guess you have to expel your tank and hope you can get it filled unless like Rick, you can get your wife to carry a 60 pound O2 concentrator around.
As an avid aviation enthusiast all my life, I hate the airlines, searched like a criminal, packed like cattle in a two block long line for bomb and metal detection, tons of EPA proof cancerous causing spent jet fuel and a CH trigger, during a long connection wait in pure bordom, read the back of my ticket and learned my life was only worth $35,000 to the airlines in the event of death, in the event of life it's worth a 1/2 oz size bag of peanuts.