Build your Own Oxygen Setup?

[allypurp]

You can get them filled at places that provide Home health care, durable medical equipment, and probably fancy pharmacies that supply the above.

I start by asking my local provider (they have many locations) or do a google search.

Just make sure your reservoir is compatible with the large filler tank owned by provider. I know most of the reservoirs I've had or looked at are compatible: Puritan Bennet (for helios and Marathon portable units), Caire (Companion and many other portable units), possibly Pulse Air?? I think everything I've researched is compatible with those brands. Just be sure to get a reservoir that will fit in your vehicle and that you can physically handle. They are very heavy, but the O2 seems to go a long way. Know that O2 will slowly evaporate from reservoirs AND portable units even when not in use....so fill up shortly before your flight.

Another portable unit I though of is made by Puritan Bennett and is called the Marathon H 850. It might be a good compromise as far as size and purpose. It has both continuous and pulse modes. But, it requires a double lumen cannula. I've used a regular single lumen cannula on a similar unit in the past. I've only found single lumen conserving cannulas. The marathon would need a double lumen if used in pulse mode. In continuous mode, you could occlude one of the 2 tubing connector sites on the portable unit. You could cut a short piece of any cannula, attach to one connector and tie it off. Or, maybe duct tape would work. Then a conserving cannula could be used on the 1 available connection to extend time O2 lasts in continuous mode.

I think the Marathon might be a good comprise if you want a unit that has pulse and continuous modes. It's easy to find, and to me, is a acceptable size and weight. It's 5.6 lbs full, will last for 22 hours on pulse mode set at 2, or 5 1/2 hours continuous at 2 lpm (it should last at least twice that long with a conserving cannula set at 1 lpm continuous). A BIG plus with the Marathon (and the Helios H300....smaller with pulse mode only) is that they can be positioned anywhere from upright to horizontally up to 90 degrees (I don't know if any others can be used other than in the upright position).

From what I can tell, the Precision Medical Easy Mate 6 + 6 (with 2 modes and single connection site) is brand new and might be harder to find. If you don't care about having pulse mode, the Caire Companion 1000 might work (Caire has all sorts of stuff).

Hope this helps. Please share any insights or thoughts any of you have.

[Ironflight]

Originally Posted by allypurp

They are very heavy, but the O2 seems to go a long way. Know that O2 will slowly evaporate from reservoirs AND portable units even when not in use....so fill up shortly before your flight.

See, these are problems - weight is actually pretty important in light airplanes, and most folks don't go fill their O2 just before a flight - we keep them filled in the hangar (or home) and take them when we think we need them. There is also a need to refill them on trips out west when you are flying at altitude - and that means you have to have reliable suppliers at airports.

Many military aircraft use LO2 systems, because most bases have the capability to maintain and fill them. But until you can get this service at most GA facilities, it really isn't practical. Sort of like trying to burn MOGAS exclusively - if you have it in your hangar, or your airport has a pump, and you only fly locally, it's great - but you just can't reliably find it on cross-countries, so you end up burning AVGAS on cross-countries.

Paul

[allypurp]

The only way I can work this out when traveling is to have a reservoir in my vehicle (I just learned about the one you mentioned). The evaporation from reservoirs and portable units is a whole lot slower when the units or turned off. I have a 35L reservoir now (easily fits in many vehicles, but is heavy). It lasts for a number of weeks unused. It lasts a good 1-2 weeks if used off and on (maybe 8 hours per day). If you can find the specs on these, you can usually get an idea of how fast O2 evaporates while TURNED OFF.

Is the reservoir you mentioned a lot more expensive than the others (? name; the concentrator that converts gas to liquid and then stores it)? One beauty of the conventional reservoirs is that they don't require electricity (something I usually don't have when out camping and such.

The lightest two portable units I know of just have pulse mode (they might be fine for your use). They are the Puritan Bennett Helios (I think the newer version is Helios H300 and the Precision Medical Easy Mate. Both of those will last approx 8 hours (turned on) when set on pulse mode 2. They are already O2 conserving devices. Not sure if using a conserving cannula on the Easy Mate (which normally uses a single lumen cannula) would help extend how long the O2 lasts TURNED ON. The Helios weighs 3.4 lbs full; the Easy Mate is a bit heavier, I think by several ounces (? still under 4 lbs).

You can buy used ones refurbished online when they're available.

[allypurp]

I wonder if the liquid O2 maker (? name) has a compatible fitting for filling some of the other portable devices. I've only seen one portable that goes with that (don't know if there are others).

If you know of any lighter and smaller portables than the two I mentioned in the last post, please let me know. For my use, I would want something that would last 6-8 hours with pulse mode set on 2.

[Greg Arehart]

Liquid oxygen requires extremely cold temperatures to stay liquid, thus the evaporation issue mentioned. I routinely deal with liquid nitrogen, which is very similar in character. I find it hard to believe that liquid oxygen will keep for any significant length of time without lots of insulation (i.e., vacuum bottle or similar) and even then a bottle of a reasonable size for an airplane will likely only remain cold for a couple days at most before it is completely evaporated away. Given the issues with obtaining LOX and keeping it cold, a compressed gas cylinder makes much more sense for a pilot.

I looked at the continuous oxygen generators and these were expensive and heavy (as well as eating space), and didn't seem to be particularly useful for an airplane like an RV given those constraints. And they will get less efficient at altitude.

My experience and opinion.

greg

[allypurp]

You are right. any small portable liquid will be gone in a couple of days if not used.

Have you seen the Inogen One G2 portable concentrator? The newer ones run on AC, DC and batteries. Weight is approx 7.25lbs with an 8 hour battery, and 8.75 lbs with a 12 hour battery. It's about 10 1/2" X 9 1/2" X 4 ". That is probably still a bit heavy and big for your purpose (as I said, I'm not a pilot, but can appreciate the problems with having O2 for all sorts of situations.

I agree about the cylinders. They are the most reliable. and, you can buy very light cylinders these days. You can also get a good size home O2 concentrator that will refill smaller cylinders. Not sure, but I think it's made by Invacare.

[Guy Prevost]

I wrote up a quick tip on how I adapted a pediatric regulator here: http://www.vansairforce.com/communit...390#post599390

[walkman]

Originally Posted by airguy

Actually, you spend the equivalent of buying the system every 27 months - assuming you refill the bottles once a month. Hydrotesting the bottles can be done very easily and cheaply, I have several high pressure bottles tested per month for my air business at $22 per test. Metallic bottles only need to be tested every 5 years, and have an unlimited lifespan as long as they are undamaged and not exposed to excess heat. Carbon fiber or fiberglass wrapped bottles must be tested every 3 years and have a maximum 15-year life span. They are also more expensive, but less weight for the quantity of oxygen they can carry.

As far as filling them - and I'm not going to advocate for or against this practice, just use your own judgement - I know many pilots who have a pair of oxygen bottles from an oxy-acetylene torch setup with a transfill valve to top off their plane bottles. It reduces your oxygen costs to pennies per refill. Say what you want about the practice - but as an analytical chemist with a couple years of actual lab time working with it, I've personally run the tests to tell you that there is no appreciable difference between "medical", "aviation", and "industrial" grade oxygen supplied in the cylinders. There used to be, yes, but with todays modern air liquefaction plants there is no economic incentive for multiple grades of purity - all the oxygen comes from the same liquid oxygen supply at the liquefaction plant. The difference is in how much paperwork accompanies it to prove it's pedigree - just like experimental aircraft and engines. From an analytical purity viewpoint, you don't see a difference until you go to the expensive UHP (Ultra High Purity) gases used for Mass Spectrometry and some gas chromatographs.

And yes, once I have my bird flying, I will have onboard oxygen and I will roll my own and fill my own - but then again I've been working with high pressure gases for close to 20 years and I'm quite comfortable with them.

There most definitely IS a different between Medical, Diving, Aviation, and Industrial Grade O2.

However its not necessarily in the gas.

There are two areas of difference. First, the moisture content. Medical oxygen has a much higher H2O content. Pure oxygen is not only toxic but can burn and dry out mucous membranes. Diving oxygen has less and aviation is the dryest. Moisture can freeze in the 1st stage of the regulator above freezing temps due to the temperature drop as the gas expands out of the tank (probably max 2,400 psi) to basically ambient. Having your O2 go offline due to ice buildup at high altitudes would be bad. You will not experience a thing, you will just quietly drift off. Remember! If you wake up and none of the instruments make sense to you, don't touch anything it will soon be over.

Second difference is the level of potential toxins and how the tanks are handled. Tanks for breathing gasses are evacuated before being filled. Non-breathing gases are just filled on top of what ever is in there. If you are renting a K bottle and cross filling with a whip or something this could be something to think about. If you own and control your own bottle, not an issue.

However, I would strongly caution anyone who plans on building their own O2 handling gear or doing their own fills. O2 is VERY, VERY dangerous! It is toxic, it can burn, it can explode with AMAZING results. Carbon steel will burn in an all O2 environment. The slightest, tiniest, most minute piece of debris like lint or a crumb of O ring inside your bottle can cause an explosion of immense devastation. Even filling a bottle too fast, or a vibration in the line as the gas flows over it can cause an explosion. Your skin, clothes, and hair will burn instantly in an O2 fire. Your clothes will be O2 saturated and will be impossible to put out. If you are doing your own fills, especially if you are getting a K bottle and doing fills with a whip or something, take a class, learn how to handle O2.

-Certified Gas Blender

[az_gila]

Originally Posted by walkman

There most definitely IS a different between Medical, Diving, Aviation, and Industrial Grade O2.

However its not necessarily in the gas.

There are two areas of difference. First, the moisture content. Medical oxygen has a much higher H2O content. Pure oxygen is not only toxic but can burn and dry out mucous membranes. Diving oxygen has less and aviation is the dryest. Moisture can freeze in the 1st stage of the regulator above freezing temps due to the temperature drop as the gas expands out of the tank (probably max 2,400 psi) to basically ambient. Having your O2 go offline due to ice buildup at high altitudes would be bad. You will not experience a thing, you will just quietly drift off. Remember! If you wake up and none of the instruments make sense to you, don't touch anything it will soon be over.

Second difference is the level of potential toxins and how the tanks are handled. Tanks for breathing gasses are evacuated before being filled. Non-breathing gases are just filled on top of what ever is in there. If you are renting a K bottle and cross filling with a whip or something this could be something to think about. If you own and control your own bottle, not an issue.

However, I would strongly caution anyone who plans on building their own O2 handling gear or doing their own fills. O2 is VERY, VERY dangerous! It is toxic, it can burn, it can explode with AMAZING results. Carbon steel will burn in an all O2 environment. The slightest, tiniest, most minute piece of debris like lint or a crumb of O ring inside your bottle can cause an explosion of immense devastation. Even filling a bottle too fast, or a vibration in the line as the gas flows over it can cause an explosion. Your skin, clothes, and hair will burn instantly in an O2 fire. Your clothes will be O2 saturated and will be impossible to put out. If you are doing your own fills, especially if you are getting a K bottle and doing fills with a whip or something, take a class, learn how to handle O2.

-Certified Gas Blender

Not as many differences as you mention. Medical oxygen is "moisturized" at delivery to the patient to lower corrosion effects. It is delivered dry.

Actual specifications here...

http://www.c-f-c.com/specgas_products/oxygen.htm

Glider pilots have been using welding oxygen for many decades and fly 10s of thousands of feet higher than RVs... It has been proven in actual use.

[Flying Scotsman]

Divers don't use pure oxygen, AFAIK. It's just compressed air.