Hey Kiritz,
You can thank obozocare and the nanny state, liberal progressive bureaucrats at the Centers for Medicare and Medicaid for your problem. I threw down on them once, got bloodied, then joined forces with the American Headache Society in 2010 in another effort to overturn their non-coverage determination on oxygen therapy for CH'ers on Medicare.
I tried to warn the AHS team working the coverage determination effort, that the bureaucrats at CMS didn't respond to prevailing practice, standards of care Level A recommended treatments or Type I medical evidence from gold standard RCTs as to the efficacy and safety of oxygen therapy as an abortive for CH... They didn't listen...
The idiot bureaucrats at CMS, (none of whom are physicians and I suspect some are on the take from the big medical insurance companies), make up their own rules, and interpret results from gold standard RCTs to meet their warped political agenda... in order to deny coverage for oxygen therapy for Medicare beneficiaries with CH... but it gets worse as you've already noted...
Thanks to obozocare, these same idiots are now forcing their non-coverage determination for oxygen therapy on all CH'ers obtaining medical insurance through obozocare state exchanges... not just Medicare beneficiaries.
Elections have consequences... The only way out of this mess is to vote the pinko-commie social progressives who did this to us out of office and repeal obozocare.
In the mean time, your story is you want to take up oxy-acetylene welding as a new hobby... Lots of CH'ers have been doing this for years... but they never tell the welding supply company what they really plan to do with it... Once you buy the first O2 cylinder (I suggest an M-Size or larger) or make a deposit to cover its cost (~ $230), you turn in empty O2 cylinders and pick up a freshly charged cylinder.
The cost of an M-Size refill will run $28.50, plus a $5.69 Hazardous Material Charge and State Tax... $2.95 here in Washington State for a grand total of $37.04 cash and carry.
You'll also need a cylinder caddy cart - $40
At this point with the M-size O2 cylinder and caddy cart in hand you've got a few options.
1. Buy a Welder's O2 regulator - $35-$50... and you're good to go if you've got a ClusterO2 kit from here at the ch.com store at the left. Welding regulators regulate the output pressure so there's no flow rate... You just keep increasing the output pressure until you reach a comfortable flow rate you can use without overfilling the reservoir bag on the ClusterO2 kit.
2. Buy a 0-25 liter/minute oxygen regulator with a CGA-540 connector from over the Internet and connect directly to the M-Size O2 cylinder.
3. Buy an M60 medical oxygen cylinder a transfiller adapter CGA-540 to CGA-540 to refill the aluminum M60 from the welder's M-size O2 cylinder, and a 0-25 liter/minute regulator with barb fitting.
The M60 shown below will cost $159.50 plus tax and shipping at the following link,
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Yes, welding oxygen is just as safe as medical oxygen. It usually comes from the same distillation plant, shipped in the same LOX truck, and stored at the refill facility in the same LOX tank...
Hope this helps...
Take care,
V/R, Batch