DIY Oxygen

[Ian]

Hi All,

 

I saw this article in the Kitplanes magazine and wondered if anyone in the community used oxygen on a regular basis and had put together their own kit or purchased a complete assembly. How much and how accessible were refills and did it sit unused or was it a considered piece of safety equipment which provided you with additional options. What size cylinders provide the most utility?

 

I also saw this article written about the use of pressure demand systems however I can't quite see that use case in the near future. I do like the approach, qualifications and experience of the author though.

 

Edited November 19, 2021 by Ian
removed typo

[spacesailor]

Slightly off topic !.

But

I aquired a ' emergency resuscitate machine ' With an oxygen bottle, the bottle was packed in a cardboard aerated box.

It was Never used or wanted to be used !.

That o2 bottle is probably available tobay. At eBay $65 for deposable bottle.

spacesailor

 

[facthunter]

There are risks with using straight Oxygen.  A diluter/demand system is  used in pressurised cockpits for depressurisation  situations. The drop down masks are used for the PAX..  RPT cabins get to about 8500 ft Cabin altitude and that doesn't affect too many people.  I regularly went to FL 175 in PNG unpressurised with O2 available but never used it. Being young helped.   Planes that regularly fly over the Rockies in northern USA have oxygen  systems fitted usually. Some countries it's FL 120 and others 10,000ft to require oxygen IF you are mucking around at these levels you should understand HYPOXIA and it's effects.  You do all this for a pressurisation endorsement including a stint in a Baro Chamber.Nev

[Ian]

My understand is that a diluter/demand system with a mask can also be used be in unpressurized aircraft to 40,000 feet and that this doesn't require a pressurisation endorsement if your plane can fly that high. However just because it's so doesn't make it safe and risk free. There's also a good report here in relation hypoxia in flight https://www.atsb.gov.au/publications/investigation_reports/1999/aair/aair199902928/tab-abstract/

From the attached CASA document.

Demand regulator: This type can be further divided into pressure demand and diluter demand type regulators. Diluter-demand and pressure-demand masks supply oxygen only when the user inhales:

• o Diluter-demand system: as the altitude increases, ambient pressure (and therefore the partial pressure of ambient oxygen) decreases, the oxygen flow increases such that the partial pressure of oxygen is roughly constant. Diluter-demand oxygen systems can be used up to 40,000 ft.
• o Pressure-demand system: the oxygen in the mask is above ambient pressure, permitting breathing above 40,000 ft but as the pressure inside the mask is greater than the pressure around the user’s torso, inhalation is easy, but exhalation requires more effort.

 

Out of curiosity, does anyone know where the baro chambers are in Australia and how much it is to do a stint in one. It might be a good birthday gift for some pilots, especially if there's video footage. 

 

DESIGN-AND-FITTING-OF-OXYGEN-SYSTEM.PDF

Edited November 20, 2021 by Ian

[facthunter]

It was Pt Cook in my day but there was one in Perth as I took a person suffering from the Bends from Christmas Island to there in the late 80's maintaining the Cabin at sea level. To do that I could not fly above FL 170. Nev

[Kenlsa]

Ian,

go to a gliding club and get them to walk you thru the ins and outs of oxy. They know more than most. It’s not just a plug and play.

Ken

[Garfly]

 

 

 

[JMLIS]

I hosted quite a few gliding camps on my property years ago. They were chasing wave flying in the July and August westerlies. Most were equipped with portable oxygen. They got to around 18k feet at times I believe. I think my highest was 11k.

[facthunter]

One of the best coverages that I've seen.. In my Airline training we had to go in a Baro chamber. You can't write. your nails go blue and you talk stupid, but think you are  OK. Nev.

[danny_galaga]

If you race drag cars, make sure you don't mix the nitrous and oxy cylinders up 😀

[KRviator]

FWIW, if it's one or two of you, I'd seriously consider a portable oxy concentrator, such as one of those from Innodyn Inogen, because it'll never run out. They're (comparatively) cheap on Marketplace or Gumtree, and once you know you have essentially unlimited O2, you'll use it. Most of them are good to the high teens and don't draw much power if you choose to run them from the aircraft supply, though they do need a little space.

Edited August 21 by KRviator

[facthunter]

 General max pressure height was 10.000 ft.Absolute Max alt was 13300 feet on anything I could find. Compressor function is reduced with height  The usual aircraft CREW equip't is a Mask with Diluter demand function.. They don't ever use the Little tubes up your nostrils in A/C. oxygen supply. Some Planes used chemical generators for emergencies. . Nev

[Ian]

Not scientific but a reasonable baseline.

On 21/08/2026 at 6:46 PM, facthunter said:

They don't ever use the Little tubes up your nostrils in A/C. oxygen supply.

I'm not really sure what you mean by this? Are you saying that canulas aren't used or endorsed by the relevant organisations or just not in common use? I'm pretty sure that both CASA and FAA have specific guidance in this regard.

 

 

[T510]

Cannula's are approved by CASA and FAA up to 18,000ft as long as they meet the required specifications.

 

No recommended for mouth breathers though.....

 

Anyone saying that they are not is just spreading misinformation 

[facthunter]

For flight crew?  My info was the limit pressure height was 13300 limited by compressor efficiency. (Supplied from the Makers data). I suppose You Tube knows best.  That fellow was talking a lot of bunkum.  Nothing beats Proper expensive and approved by the Authority, training. You can't "feel" you are getting hypoxia. You actually feel everything is fine, as your performance drops right off. Nev

[T510]

41 minutes ago, facthunter said:

For flight crew?  My info was the limit pressure height was 13300 limited by compressor efficiency. (Supplied from the Makers data). I suppose You Tube knows best.  That fellow was talking a lot of bunkum.  Nothing beats Proper expensive and approved by the Authority, training. You can't "feel" you are getting hypoxia. You actually feel everything is fine, as your performance drops right off. Nev

Maybe you should check the regulations rather than spouting misinformation.

 

CASA Part 91 MOS covers the requirements 

[facthunter]

Where's the" Misinformation" in my Post.?  Nev

[facthunter]

I've also just spent 40 Minutes looking for Oxygen info on the CASA site you listyed and much more,.  so perhaps you could give more precise information just where it is?  Nev

[Ian]

The relevant information. 
Acceptable means of compliance and guidance material
General Operations and Flight Rules Part 91 of CASR

Above 18000 you need a mask that covers the mouth and nose - below that cannulas are sufficient.
Flow rates are specified and oxymiser cannulas are specifically stated to meet lower flow rates.
 

[Ian]

Oxygen generators appear to be a reasonable way to fly to at least 18000 feet for a single person or 14000 for two people.
You probably should ensure that you have a CO sensor as CO can clog the molecular sieve leading to a lack of oxygen concentration.

[facthunter]

I don't seem to be able to enlarge  that plus the Maker of the Best brand stated only OK to just over 13000 feet.  I used to regularly go to Lae from Moresby at FL180 unpressurised. You need to know what you are doing. Quite a few People have come to grief..  It had a mask with a diluter demand system, including a Microphone.   Nev

[Ian]

13 hours ago, facthunter said:

I don't seem to be able to enlarge  that plus the Maker of the Best brand stated only OK to just over 13000 fee

Not sure what the Best Brand is. 
Easier to read as part of the PDF so the link has been provided.
The key points oxygen may have benefits even below 10000 especially at night, if you're older or you're an ex-smoker or fly at night. Put simply your judgement and ability to concentrate are likely to be better.

Because you're not consuming a limited supply from an O2 bottle and the fact that you can now easily monitor your O2 levels it does provide options which in the past were simply not available.
https://www.casa.gov.au/resources-and-education/publications/guidance-material/acceptable-means-compliance-and-guidance-material?search_api_fulltext=&dt_published[min]=&dt_published[max]=&field_tx_rules_part=71
Inogen appear to be pushing their device as being suitable to 18000 feet.
https://www.inogenaviator.com/