Medical vs Aviation O2 systems?

bflynn

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Brian Flynn
Is there a difference?

Looking at some systems online and I see that for what Sporty's charges for an O2 regulator, you can get a whole fancy portable medical O2 tank on wheels from Amazon. Is there a difference between medical and aviation O2 systems or do we suffer from the "rich pilot" markup?
 
Search on here for something like "dr bruice o2 system"

There is a big thread in here for a good DIY system
 
Biggest difference is:
$$$$$$$$$$$$$$$$$$$$$$$$$$$$
& "Big Brother"
 
There's not much difference as far as the tanks go though the aviation units tend to be aluminum models where more often than not the cheaper steel tanks are used for medicine as weight isn't an issue.

If you're going to use a simple flow-based system, the regulator is nothing special (in fact, it IS identical).

I would seriously consider using a demand based system (I have the Nelson but the MountainHigh guys I've talked to a bunch of times and they have a good product as well). It lets you stretch that tank capacity a good long time. Oxygen is cheap...until you run out. I like the duration the demand regulator gives me.
 
Where are you going to get it filled? Almost ALL aviation oxygen fill stations at airports use the CGA 540 valve (which btw is the same valve that most welding rigs use, I believe). The medical valve is the CGA 870 valve and some have that valve or you can get an adapter. The problem is most medical places want to just swap tanks, and that is true of welding supply places too. YMMV. The aviation fill stations at airports are the only places Ive ever gotten my tank filled for $20 to $40 a fillup.

Whatever you do, get at least a 24 cu ft tank because they charge the same to fill any tank up to that size. This is about a 4 hour tank for one person.

http://www.ozoneservices.com/products/OLO/images/tank/02-b.jpg
 
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The local oxygen supply place (which if you walk in you'd think was a welding shop but they advertise themselves out as medical), will fill your tank but if I take it to the closest facility, it takes a day for them to turn it around (has to go to another facility and come back). They'll swap tanks on the spot, but they will fill and return your tank if you want.

I regularly go in there anyhow because I have CO2 tanks for a soda carbonator and Nitrogen tanks for my wine bar.

Given the increase in popularity in Nitrox (EAN) diving these days, a lot of scuba places will fill you as well.
 
The dive shop that I used to work with did O2 fills for 50 cents a cubic foot. I know shops that do it for as little as 30 cents a cubic foot. That sounds much better than the prices quoted above for aviation fill stations at airports. The dive shops are all using aviators O2.
 
There's no difference in the O2. The only thing that changes is what paper the gas supplier hands you with the tank.
 
There's no difference in the O2. The only thing that changes is what paper the gas supplier hands you with the tank.


I recall reading that the difference between medical/aviation O2 and welding O2 is the amount of allowable moisture content...not that it really matters but there is a slight difference in the standards.
 
I recall reading that the difference between medical/aviation O2 and welding O2 is the amount of allowable moisture content...not that it really matters but there is a slight difference in the standards.

Not quite. ABO requires less moisture content. The truth is, that bulk O2 these days is cryogenically separated and dry no matter what the customer buys. It all comes from the same lox tank. I worked in three different hospitals. If we wanted the patient to have humidified oxygen we ran it through a bubbler.
 
I've been using an aluminum E tank (24 cu ft) and pulse dose medical regulator with Oximixer cannula for several years. I get it filled at a dive shop. Works great.
 
My father passed away a little over a year ago and I have his medical oxygen equipment. It includes a small aluminum tank, cannulas and a machine to fill the tank. Could i use this in my aircraft?
 
I recall reading that the difference between medical/aviation O2 and welding O2 is the amount of allowable moisture content...not that it really matters but there is a slight difference in the standards.

As noted, all of the O2 now is cryogenically derived, and hence zero moisture (really hard for water to survive minus 100 F!) There *is* a difference in the fill procedures, though... welding can be just refilled... O2 gets filled, emptied to carry away any impurities, and filled again. Aviators has the fill/empty process more than once... which is kind of a PITA for the fill station. And of course, folks are concerned about liability, but I can't remember hearing of anyone getting sued for ABO quality... John Deakin wrote a nice article on AvWeb decades ago about the legality and practicality of using any oxygen for aviation... he endorses it.
 
My father passed away a little over a year ago and I have his medical oxygen equipment. It includes a small aluminum tank, cannulas and a machine to fill the tank. Could i use this in my aircraft?
Sorry to hear about your Dad, Richard. :(

You could use that setup, but caution!

The machine to fill it is an oxygen concentrator... but it puts out relatively low pressure. So that small aluminum tank doesn't have much capacity. You might be better off getting the 12 volt adapter for the concentrator itself, and taking THAT along in the aircraft. And you'll want to set the flow rate for altitude. Conventional wisdom is 1 LPM (liter per minute) per 10,000'... but I find I'm more comfortable with 50% more, typically... YMMV.

Here's an Aviation Consumer article from three years ago... let me know if you have any questions!

https://tinyurl.com/AvConO2Conc
 
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Understand that medical concentrators have pretty low working altitudes (10,000' max, which covers the 8000 Max cabin elevation on airliners) which pretty much makes them useless at the altitudes you need oxygen.
Further many won't flow more than 3 l/M so you may find they're not going to do well with your aviation canulas. Finally, these things are pretty much designed to used continuously for most of the day, so intermittent use (like occasional in flight use) will deplete the sieve beds internally much faster than designed.
 
My father passed away a little over a year ago and I have his medical oxygen equipment. It includes a small aluminum tank, cannulas and a machine to fill the tank. Could i use this in my aircraft?
I have a medical based O2 setup so comments are limited to medical vs aviation.

First off, the tank valve/adapter for medical is different than for aviation / welding / scuba. So you might need a fill adapter (about $50). I have had my medical 02 tank filled at FBOs...just made sure I had the adapter as I'm guessing most dont have one. If you have a prescription for medical 02 you can just fill it that way. But if you're at an airport low on 02 then the adapter will be important.

Cannulas: Often medical cannulas do not have the oximizer option. The oximizer is a medallion shaped piece in line with the tubes before the nose. The other type looks like a moustache. These are to be taken seriously for aviation. Using a oximizer can extend the life of a single bottle as much as something like 8x. Why have 1 adult on a 1lpm bleed when 2 can share a 0.5lpm bleed (or even 0.25lpm) when all using oximizers.

Finally, medical 02 doesn't usually have a flow indicator but your gonna want that in the plane as well to verify there is gas flowing. Often it's just a tiny propeller looking thing or a ball that floats up in a tube.

It can be much cheaper but definitely some DIY.

If you are going to do a lot of 02 flights just get a Mountain High (?) pulsed system.
 
The aviation fill stations at airports are the only places Ive ever gotten my tank filled for $20 to $40 a fillup.

if in your area you have access to a dive shop, scuba guys will refill a 22CU oxygen tank for $6 to $9. If you live anywhere near a body of water, you’ll find a dive shop somewhere.
 
Hi Paul, I was going to ask on CFO but thought I would try here first.

Thank you for the condolences but dad was very sick, he's in a better place now, he got to see Joanne and I get married before he passed, we were married by the same person you were.

The machine he had is 2 part, the base is the concentrator that supplied him with oxygen around the house, the 2nd part sat on top and was a pump to fill the tanks, I assume under higher pressure. My concern was if the aluminum tank was safe to use in my airplane. I rarely go over 12,500 for more than an hour at a time. I have all the equipment, including several new cannulas

Rick
 
I have a medical based O2 setup so comments are limited to medical vs aviation.

First off, the tank valve/adapter for medical is different than for aviation / welding / scuba. So you might need a fill adapter (about $50). I have had my medical 02 tank filled at FBOs...just made sure I had the adapter as I'm guessing most dont have one. If you have a prescription for medical 02 you can just fill it that way. But if you're at an airport low on 02 then the adapter will be important.

Cannulas: Often medical cannulas do not have the oximizer option. The oximizer is a medallion shaped piece in line with the tubes before the nose. The other type looks like a moustache. These are to be taken seriously for aviation. Using a oximizer can extend the life of a single bottle as much as something like 8x. Why have 1 adult on a 1lpm bleed when 2 can share a 0.5lpm bleed (or even 0.25lpm) when all using oximizers.

Finally, medical 02 doesn't usually have a flow indicator but your gonna want that in the plane as well to verify there is gas flowing. Often it's just a tiny propeller looking thing or a ball that floats up in a tube.

It can be much cheaper but definitely some DIY.

If you are going to do a lot of 02 flights just get a Mountain High (?) pulsed system.


Thank you for the response. I'm not worried about refilling the tank at an airport, I have dads home based concentrator which is 2 part, base is the concentrator, the top is a pump/tank filler, I would be filling the tank myself. The tank is an aluminum tank, approx 3" in diameter and about 12" tall. I'm more worried about it being safe in an airplane at 12,000 - 14,000 feet.
 
if in your area you have access to a dive shop, scuba guys will refill a 22CU oxygen tank for $6 to $9. If you live anywhere near a body of water, you’ll find a dive shop somewhere.

This. They won't sell O2 to divers lacking an advanced nitrox certification or higher, but often they'll be happy to fill for pilots, and you're unlikely to find a better price--though dive shops may lack the correct fill adapter.
 
This. They won't sell O2 to divers lacking an advanced nitrox certification or higher, but often they'll be happy to fill for pilots, and you're unlikely to find a better price--though dive shops may lack the correct fill adapter.
There is some irony to this. If you are a diver you would then need open water, basic nitrox, advanced nitrox and the majority have the advanced and rescue certs as well if not more. Pretty much all of them cover the basics of use and effects of O2 in a progressive manner. But none of the dive industry certifications are law or code or regulation. Just private organizations duking it out for market share.

Yet a private pilot with his 14.CFR.xxx certificate can walk in and get O2 having pretty much zero training and mostly likely no hands on experience. Damn pilots are cool :)
 
Scuba certification is a joke. I suspect the issue is liability. Basic OW doesn't much talk about O2 at all. If a diver exceeds his cert and somehow they can imagine the gas might be a problem, the dive shop is liable. They just trust pilots more.
 
There is some irony to this. If you are a diver you would then need open water, basic nitrox, advanced nitrox and the majority have the advanced and rescue certs as well if not more. Pretty much all of them cover the basics of use and effects of O2 in a progressive manner. But none of the dive industry certifications are law or code or regulation. Just private organizations duking it out for market share.

Yet a private pilot with his 14.CFR.xxx certificate can walk in and get O2 having pretty much zero training and mostly likely no hands on experience. Damn pilots are cool :)

All true; I suspect the big difference between diving and aviation use is in training and how quickly things go bad if O2 is used incorrectly underwater. All private pilots learn the regs governing O2 use; all divers (if they don't go on to complete Nitrox training) are only taught that they're allowed to breathe compressed air only, and any discussion of how quickly O2 becomes toxic under pressure is deferred to those later courses...since the divers can't buy O2 until they complete them.

Being 500' too high without O2, while not a good idea, won't greatly affect a lot of pilots. Being 30' too deep on pure O2 will kill a significant fraction of divers, and while it's harder to get in trouble breathing O2 enriched air (nitrox) underwater, it's still quite possible.
 
But none of the dive industry certifications are law or code or regulation. Just private organizations duking it out for market share.

I stopped paying attention to dive certifications when some time after I earned my Dive Master cert, Put Another Dollar In (PADI) created the Master Diver "certification".

Now and then I still receive notifications of new "certifications" they have created. I think the last one I saw was "Clearing You Mask Without Drowning Expert" (or something along those lines).
 
I have a DIY oxy system based on a medical regulator and a 44 cubic foot steel tank. Total cost a few hundred dollars. Works perfectly and I can make as many outlets as I want for pennies. I carry an adapter with me so I can go to any welding shop and get them to re-fill my tank for a couple of beers,etc. Of course some of you equate happiness to spending so don't do what I did.oxy top.JPG
 
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Where can you get the adapter to allow filling your DIY medical systems at O2 facilities that are set up for aviation systems?
 
They no longer sell the one I ordered at Amazon but shown below is the description from the past order. I think it was around $60. Ironically this is the first item where the DIY approach starts adding costs vs cutting costs when compared to aviation 02 setups. I think the CGA870 is the medical and the CGA540 is the welding/aviation/scuba.

Oxygen Transfill Adaptor CGA870 to CGA540 Medical Aviation Scuba EMS CGA 870 540

EDIT: I see one on e-bay for about $45
 
Where can you get the adapter to allow filling your DIY medical systems at O2 facilities that are set up for aviation systems?
I simply made one using a short block of brass tapped for the appropriate 3 pipe threads and screwed in the two male B nut connectors and a 2000 psi pressure gauge. I NEVER buy expensive oxy at an aviation supplier. I just bought a couple of the tall K size cylinders at a welding gas supplier. When the pressure gets low for flying I use the oxy for welding. The 44 cubic cylinder will last along time and fits perfectly between the seats of my Cessna and I can refill at any welding shop.
 
There are a few things to know when home brewing an O2 system; properly cleaning any components that will see high-pressure O2 is particularly important. I'm a big fan of the (recently updated) Oxygen Hacker's Companion http://www.airspeedpress.com/newoxyhacker.html It's geared to technical divers, but chapters relevant for pilots include:

- How to O2 clean your gear (and is oxygen cleaning really necessary)?
- Legal issues. Do you need a prescription to buy/use O2? Is it legal to mix your own dive gas?
- Is welding O2 safe to breathe? The truth about O2 grades.
- Dealing with compressiblity in the real world
- How to assemble your own low cost dive emergency treatment or aviation O2 set.
- Dealing with gas suppliers - an insider's guide to buying oxygen and helium.
- Buy or rent your O2 storage tanks?
- Where to buy O2 tanks - medical and industrial - for half what your local gas dealer charges.
- How to get "orphan" medical and welding tanks filled.
- Why aluminum O2 tanks have green shoulders.
- Easy to make, no-machining SCUBA-to-NPT, NPT-to-SCUBA, and medical O2 adaptors.
- How to cut the cost of hydro testing in half.
 
Years ago I was a paramedic/firefighter. We were welding some compartments on one of the fire engines and the guy working the torch says "Crap, I'm out of oxygen." I pointed out we had all kinds of oxygen and went and pulled the thumper bottle off the ambulance so he could finish.
 
This subject is a perennial, and rightly so. Flying with oxygen means no headaches, increased vision especially at night, clearer thinking, ability to top the weather, depending on how high your plane can go. I'm chiming in this time to note that anyone that has been considering one of the small and very neato-seeming oxygen concentrators (as was the case with me), needs to know those things are only capable of providing a 90% saturation. At sea level. Up high, I think only the very best of them can maintain 90% up to 10K. Above that . . . and of course that's where one would be . . . their capacity falls even further. So they're useless. I've never seen anything close to 90% on my oximeter and would be concerned if I did. I bump up the regulator a notch if it gets to 95%. I only learned of these concentrator limitations after watching them for years.

Air Force jets use concentrators but they must be of a much higher capacity than these little portable units that would be suitable for GA.

Just to note, I use a medical pulse-dose regulator with an Oxymizer cannula and a 24 cu.ft. aluminum "E" bottle which I get filled at a local dive shop. I bought everything on eBay and total cost was not more than $100. The regulator, as is the case with a lot of "used" medical equipment, was still brand new. I think it was $35. Mine is made by Devilbiss (PD1000) but there are at least two others on the market which I'm sure work just as well.
 
those things are only capable of providing a 90% saturation.

I suggest you look at the Inogen Aviator unit, then acknowledge your error... the spec and demonstrated performance is definitely above 90%, up to the FAA endorsed 18,000' equipment ceiling.

Perhaps you're thinking of the medical units, but failing to qualify your comment?
 
A fill lasts me a long time. I've got the Nelson/Precise demand regulators and get over 20-seat hours out of a fill. MountainHigh has a comparable unit (theirs is electronic where Precise is purely mechanical).
 
I have been filling the O2 bottles in my plane from my Oxygen welding tank using the proper adapter for over 20 years. I don't use as much O2 in Florida as I did out West.
 
A fill lasts me a long time. I've got the Nelson/Precise demand regulators and get over 20-seat hours out of a fill. MountainHigh has a comparable unit (theirs is electronic where Precise is purely mechanical).

I've got both... FWIW, the Nelson pulser doesn't work well for shallow breathers like me...

Paul
 
> "Perhaps you're thinking of the medical units, but failing to qualify your comment?"

This question implies that the Inogen Aviator is not simply a re-badged medical unit. Is that not the case?
 
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