Can't Handle Altitude Anymore

[sferguson524]

For our veterinary hospital, we have to use only Medical Grade Oxygen. We are not allowed to use welding tanks. We get it from the same distributor as welders, but the Medical grade tanks have to be certified as such.

So I have to ask the question: Is welding grade oxygen really good enough for people to breathe.

As the son of someone who worked in the industrial gas business for 25+ years, the medical grade ox, welder's ox, and ABO are ALL drawn off the same many thousand gallon LOX storage tank. Medical bottles are completely emptied before filling, welder's bottles are topped up.

 

[frfly172]

I use medical cylinders,with a nasal cannula . Get it refilled from medical supply. Good to have a pulse ox ,so you get the proper mixture.

 

[James331]

I've heard the in countries outside the US there is considerably less freedom in it

 

[Jay Honeck]

Hey Jay, what did you finally decide on?

I posted this info in another thread:

But the Inogen website says it's good up to 10,000 feet. I wonder if the first company modified it for service at 18K or is just blowing hot air.

We went with Aerox. Got a teensy little tank that I mounted to the back of the pilot's seat in the -8A that (with the rebreathing cannulas) lasts us about 8 hours at 10,000'.

Because the tank is so small, I bought another one at OSH this year. We now keep both of them topped off.

Interestingly, one of the upsides of the teensy tank is that most places have refused to charge us for refills, since it only takes a few seconds to fill.

We find ourselves using O2 quite often down here in South Texas, to escape the heat and bumps of the afternoon buildups. It helps to have a plane that can get to 10,000' relatively quickly.

Here's a pic of us using the system (Note Mary's mustache!):

 

[CTLSi]

I heard DA does not matter for oxygen, because the air in your langs is at body temperature.

All performance related altitude numbers are given in DA. So, the ceiling, max op altitude, oxygen requirements, engine efficiency and lift coefficients are all affected and given in reference to DA, not MSL or AGL.

 

[Neal Howard]

I bought an Aerox 22cu ft "M" sized system for my RV-6 so I'd have enough capacity for a complete round trip from Texas to Idaho and back. Worth every penny. I've been just strapping into my co-pilot side seat along with my dufflebag suitcase that I usually take on long trips. I need to fabricate some sort of mounting bracket to locate it in my baggage area like this fellow did.

 

[N321SR]

The trick is to own your own cascade cylinders and don't exchange them for fills. I recommend 4500 psi service 504cuft steel. You can drop them for refills at the gas supplier (at least we can here in Billings) and pick your own cylinder back up a few days later. That way you know nothing else is in your oxygen tank if you didn't put it there. There is no water in the filling rack at the gas supplier and the plumbing is common to the ABO and medical cylinder filling. Your fill will be dry and pure. I've got my name and address stenciled in big letters on my tanks so they don't get lost.

 

[FastEddieB]

All performance related altitude numbers are given in DA. So, the ceiling, max op altitude, oxygen requirements, engine efficiency and lift coefficients are all affected and given in reference to DA, not MSL or AGL.

It took a few seconds to confirm what I had also heard:

"Density altitude is pressure altitude corrected for temperature. Since the air in the lungs is always (for practical purposes) at 37°C, the air in our lungs is always at the same density altitude for a given pressure altitude regardless of ambient temperature!"

If anyone knows if that is incorrect, please let me know.

Oh, and I'm pretty sure "max op altitude" and "oxygen requirements" are not generally given as DA, the former I've most often seen as just "msl" and the latter "cabin pressure altitude", neither referencing temperature.

 

[Marauder]

It took a few seconds to confirm what I had also heard:



"Density altitude is pressure altitude corrected for temperature. Since the air in the lungs is always (for practical purposes) at 37°C, the air in our lungs is always at the same density altitude for a given pressure altitude regardless of ambient temperature!"



If anyone knows if that is incorrect, please let me know.



Oh, and I'm pretty sure "max op altitude" and "oxygen requirements" are not generally given as DA, the former I've most often seen as just "msl" and the latter "cabin pressure altitude", neither referencing temperature.

You're correct. DA is associated with performance of the wing and engine.

Requirements for O2 are based on MSL

https://www.faasafety.gov/files/gslac/courses/content/25/183/O2 requirements chart.pdf

14 CFR 91.211