Mountain High Cannula/Mask?

[John McLaughlin]

Does everyone stick to the 18k limit for the cannula and 25k for the mask,

or are these limits considered advisory only?

[[email protected]]

I use the blue mask if I'm planning to go above 18k and have been above 27k with no issues. (It is an unhelpful fire drill at 17k changing systems in a cockpit, so if you plan to go high, just start with the mask. You can fit it on the ground and hang it from the neck strap. Then pull the top strap back over the head when you get above 10k if you wish.)

It's not clear to me the regs or the physiology eliminate the cannula above 18k if you can remember to use your nose, but the mask covers the bases and looks cool in those wave picts.

What works can vary widely depending on the person, so pulse oximeter is useful to verify things are working. (A brain in la-la land is not dependable to do this on it's own. Especially in and above the 20's.)

Dress warm now...

[RR]

On Tuesday, October 1, 2019 at 6:45:06 AM UTC-4, John McLaughlin wrote:
> Does everyone stick to the 18k limit for the cannula and 25k for the mask,
>
> or are these limits considered advisory only?

The legalitys are not so clear, but practically it is about remembering to breathe only with your nose with the cannula. Something I felt i could do, and so far have remembered. It is much easier to hydrate and communicate with the cannula. Just don't forget...

RR

[Charlie M. (UH & 002 owner/pilot)]

Non smoker, rather active, good health.....may be fine.
Couch potato, smoker, heart issues, etc., may be in bad shape walking in Denver, let alone flying higher....yes, I have had to run through the Denver airport from a late flight trying to catch a connecting flight.....sucked carrying a heavy bag...
YMMV......

Yes, finger probe (I believe under $100US) will basically tell you how you're doing on O2.

[Tango Eight]

On Tuesday, October 1, 2019 at 6:16:30 PM UTC-4, Charlie M. (UH & 002 owner/pilot) wrote:
> Non smoker, rather active, good health.....may be fine.
> Couch potato, smoker, heart issues, etc., may be in bad shape walking in Denver, let alone flying higher....yes, I have had to run through the Denver airport from a late flight trying to catch a connecting flight.....sucked carrying a heavy bag...
> YMMV......
>
> Yes, finger probe (I believe under $100US) will basically tell you how you're doing on O2.

Unless you hyperventilate. What happens then?

T8

[Tango Eight]

On Tuesday, October 1, 2019 at 3:44:11 PM UTC-4, RR wrote:
> On Tuesday, October 1, 2019 at 6:45:06 AM UTC-4, John McLaughlin wrote:
> > Does everyone stick to the 18k limit for the cannula and 25k for the mask,
> >
> > or are these limits considered advisory only?
>
> The legalitys are not so clear, but practically it is about remembering to breathe only with your nose with the cannula. Something I felt i could do, and so far have remembered. It is much easier to hydrate and communicate with the cannula. Just don't forget...
>
> RR

There are several reasons any given person might not breathe well on a cannula at high altitude, mouth breathing is only one. Here's another: It is really easy to hyperventilate on a cannula at 20+K. Trivially easy in fact.. If you must use a cannula above 18K (which I recommend against), do not skimp on the O2, don't use a dumb ass "oxy-miser" anything above 18K. Turn up the flow. If in doubt, turn it up some more. Not a bad idea to monitor heart rate as well as O2 saturation. Tachycardia is reliable indicator of breathing problems, and it will catch hyperventilation (O2 saturation will not, key word alkalosis).

It's much easier to breathe well (and reliably) on a mask, provided the mask fits and seals acceptably well. If you aren't breathing well, hydration and communication are going to cease to matter.

T8

[Bruce Hoult]

On Tuesday, October 1, 2019 at 3:16:30 PM UTC-7, Charlie M. (UH & 002 owner/pilot) wrote:
> Non smoker, rather active, good health.....may be fine.
> Couch potato, smoker, heart issues, etc., may be in bad shape walking in Denver, let alone flying higher....yes, I have had to run through the Denver airport from a late flight trying to catch a connecting flight.....sucked carrying a heavy bag...
> YMMV......
>
> Yes, finger probe (I believe under $100US) will basically tell you how you're doing on O2.

You can get them for $15 now, and better ones for $25.

According to tests, even the cheapest are accurate, it just comes down to build quality and extra features e.g. nice graph of your pulse depth (and numerical assessment of that), BlueTooth connection to your phone etc.

I just got an "Innovo Deluxe Fingertip Pulse Oximeter with Plethysmograph and Perfusion Index" for $26.99. I haven't used it in anger yet, but I'm planning to see what it says on my 12 hour flight from SFO to AKL tonight :-) It seems good so far.

https://www.amazon.com/gp/product/B07JBJ9BCR/ref=ppx_yo_dt_b_asin_title_o00_s00

[Richard Pfiffner[_2_]]

On Tuesday, October 1, 2019 at 5:12:51 PM UTC-7, Bruce Hoult wrote:
> On Tuesday, October 1, 2019 at 3:16:30 PM UTC-7, Charlie M. (UH & 002 owner/pilot) wrote:
> > Non smoker, rather active, good health.....may be fine.
> > Couch potato, smoker, heart issues, etc., may be in bad shape walking in Denver, let alone flying higher....yes, I have had to run through the Denver airport from a late flight trying to catch a connecting flight.....sucked carrying a heavy bag...
> > YMMV......
> >
> > Yes, finger probe (I believe under $100US) will basically tell you how you're doing on O2.
>
> You can get them for $15 now, and better ones for $25.
>
> According to tests, even the cheapest are accurate, it just comes down to build quality and extra features e.g. nice graph of your pulse depth (and numerical assessment of that), BlueTooth connection to your phone etc.
>
> I just got an "Innovo Deluxe Fingertip Pulse Oximeter with Plethysmograph and Perfusion Index" for $26.99. I haven't used it in anger yet, but I'm planning to see what it says on my 12 hour flight from SFO to AKL tonight :-) It seems good so far.
>
> https://www.amazon.com/gp/product/B07JBJ9BCR/ref=ppx_yo_dt_b_asin_title_o00_s00

My Sansung Galaxy S8 phone with the Samsung Health app has a pulse oximeter.

Richard
www.craggyaero.com

[Tango Eight]

On Tuesday, October 1, 2019 at 3:44:11 PM UTC-4, RR wrote:

> The legalitys are not so clear [...]

FAR 23.1447 spells it out (for certificated aircraft). Above 18K the requirement is for a mask that covers nose and mouth.

The fact that some people can get away with a cannula at 26K (once) does not mean that this is a sound practice. We've had two hypoxia incidents (that I know of) at Mt Washington due to pilots emulating certain old timers. Physiology varies. Physical fitness doesn't seem to be a factor (in fact casual observation suggests the reverse :-)).

T8

[Eric Greenwell[_4_]]

RR wrote on 10/1/2019 12:44 PM:
> On Tuesday, October 1, 2019 at 6:45:06 AM UTC-4, John McLaughlin wrote:
>> Does everyone stick to the 18k limit for the cannula and 25k for the mask,
>>
>> or are these limits considered advisory only?
>
> The legalitys are not so clear, but practically it is about remembering to breathe only with your nose with the cannula. Something I felt i could do, and so far have remembered. It is much easier to hydrate and communicate with the cannula. Just don't forget...

The Mountain high EDS units will alarm if you don't breathe frequently enough, so
that might be sufficient to remind pilots to breather through their nose.
Continuous use of an oximeter that alarms with a low SPO2% may be a useful
additional reminder to breathe properly, and I think I would use one even if I was
using a mask.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorgliders/publications/download-the-guide-1

[Eric Greenwell[_4_]]

Tango Eight wrote on 10/1/2019 3:47 PM:
> On Tuesday, October 1, 2019 at 3:44:11 PM UTC-4, RR wrote:
>> On Tuesday, October 1, 2019 at 6:45:06 AM UTC-4, John McLaughlin wrote:
>>> Does everyone stick to the 18k limit for the cannula and 25k for the mask,
>>>
>>> or are these limits considered advisory only?
>>
>> The legalitys are not so clear, but practically it is about remembering to
>> breathe only with your nose with the cannula. Something I felt i could do,
>> and so far have remembered. It is much easier to hydrate and communicate
>> with the cannula. Just don't forget...
>>
>> RR
>
> There are several reasons any given person might not breathe well on a cannula
> at high altitude, mouth breathing is only one. Here's another: It is really
> easy to hyperventilate on a cannula at 20+K. Trivially easy in fact.. If you
> must use a cannula above 18K (which I recommend against), do not skimp on the
> O2, don't use a dumb ass "oxy-miser" anything above 18K. Turn up the flow. If
> in doubt, turn it up some more. Not a bad idea to monitor heart rate as well
> as O2 saturation. Tachycardia is reliable indicator of breathing problems, and
> it will catch hyperventilation (O2 saturation will not, key word alkalosis).
>
> It's much easier to breathe well (and reliably) on a mask, provided the mask
> fits and seals acceptably well. If you aren't breathing well, hydration and
> communication are going to cease to matter.

Does it matter which face mask is used? The one that came with the Mountain High
EDS units I have is very basic, with a very small cavity, so I think it would not
increase the amount of CO2 you breathe. I'm assuming it's the CO2 content that's
the important factor - is that true?

They do have a mask with a rebreather bag, so perhaps that's the one you should use?

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorgliders/publications/download-the-guide-1

[Tango Eight]

On Wednesday, October 2, 2019 at 8:52:12 AM UTC-4, Eric Greenwell wrote:
> Tango Eight wrote on 10/1/2019 3:47 PM:
> > On Tuesday, October 1, 2019 at 3:44:11 PM UTC-4, RR wrote:
> >> On Tuesday, October 1, 2019 at 6:45:06 AM UTC-4, John McLaughlin wrote:
> >>> Does everyone stick to the 18k limit for the cannula and 25k for the mask,
> >>>
> >>> or are these limits considered advisory only?
> >>
> >> The legalitys are not so clear, but practically it is about remembering to
> >> breathe only with your nose with the cannula. Something I felt i could do,
> >> and so far have remembered. It is much easier to hydrate and communicate
> >> with the cannula. Just don't forget...
> >>
> >> RR
> >
> > There are several reasons any given person might not breathe well on a cannula
> > at high altitude, mouth breathing is only one. Here's another: It is really
> > easy to hyperventilate on a cannula at 20+K. Trivially easy in fact.. If you
> > must use a cannula above 18K (which I recommend against), do not skimp on the
> > O2, don't use a dumb ass "oxy-miser" anything above 18K. Turn up the flow. If
> > in doubt, turn it up some more. Not a bad idea to monitor heart rate as well
> > as O2 saturation. Tachycardia is reliable indicator of breathing problems, and
> > it will catch hyperventilation (O2 saturation will not, key word alkalosis).
> >
> > It's much easier to breathe well (and reliably) on a mask, provided the mask
> > fits and seals acceptably well. If you aren't breathing well, hydration and
> > communication are going to cease to matter.
>
> Does it matter which face mask is used? The one that came with the Mountain High
> EDS units I have is very basic, with a very small cavity, so I think it would not
> increase the amount of CO2 you breathe. I'm assuming it's the CO2 content that's
> the important factor - is that true?
>
> They do have a mask with a rebreather bag, so perhaps that's the one you should use?
>
> --
> Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
> - "A Guide to Self-Launching Sailplane Operation"
> https://sites.google.com/site/motorgliders/publications/download-the-guide-1

I've had good luck with (decent quality, form fitting) re-breather mask systems on constant flow. I don't breathe well on the EDS / cannula system at high altitude. My breathing tends to get sort of "lazy" by 16 - 18K and I find I have to use one of the higher delivery modes to maintain high saturation. Re-breather mask fixes that and CO2 seems the most likely reason.

I have not tried the MH masks. I've seen one (blue rubber, apparently decent quality) that looked like it might be worth a try.

Minor rant: *Any* hard plastic mask (Aerox & Mountain High are both guilty of selling such) that looks like an emergency medical single use mask has no place in the cockpit... you would honestly just be better off sucking on the end of the hose. I've seen these things literally fall apart before first use as someone unwrapped the sealed plastic bag it was shipped in. It's completely unconscionable that anyone would sell you something this crummy as part of a life support system.

While I'm at it, I'd encourage folks to take a skeptical look at their oxygen delivery gear. The old style Aerox needle valve/rotameter is notorious for breaking under normal handling, as are the old green plastic barbed fittings. Expect anything plastic or rubber to become more fragile when cold soaked, don't expect that these O2 system manufacturers have done any durability or cold soak testing of their products: they obviously haven't. Again... I find it completely unconscionable that anyone sells such rubbish for life support purposes, but it's out there, beware.


T8

[RR]

On Wednesday, October 2, 2019 at 7:17:16 AM UTC-4, Tango Eight wrote:
> On Tuesday, October 1, 2019 at 3:44:11 PM UTC-4, RR wrote:
>
> > The legalitys are not so clear [...]

I should have been more specific, the legalities in experimental aircraft (many if not most of our gliders) are not so clear.

And I am sorry if I implied a recommendation. I am just speaking of my own experience (18 years of diamond and Lenny climes) accompanied with, pulse oximeters (from back when they were expensive) and backup systems at hand.

I totally agree with T8 about not scrimping on the Ox. No using the oxisaver flow levels. But for me, with full beard and mustache, I know what is being delivered to my nose, where I would be concerned about leakage from a mask.

Ox at altitude is not something to take lightly. And single place aircraft require real diligence in acquiring the knowledge about your personal reaction to hypoxia. Know your symptoms, and learn to react quickly.

One thing that is very important to know is the Ox saturation curve has a "kink" in it at 25k. Flights to 24k are like scuba diving, flights above are like cave diving. You need to have redundant systems. Everyone knows climbers have ascended Everest without Ox and think they can descend if something goes wrong, but the amount of "useful conciseness" you have above 27k is measured in seconds not minutes.

RR


>
> FAR 23.1447 spells it out (for certificated aircraft). Above 18K the requirement is for a mask that covers nose and mouth.
>
> The fact that some people can get away with a cannula at 26K (once) does not mean that this is a sound practice. We've had two hypoxia incidents (that I know of) at Mt Washington due to pilots emulating certain old timers. Physiology varies. Physical fitness doesn't seem to be a factor (in fact casual observation suggests the reverse :-)).
>
> T8

[[email protected]]

https://www.faa.gov/pilots/training/airman_education/media/AC%2061-107A.pdf

Page 13 is the table of useful consciousness versus altitude, and is surrounded by a pretty good discussion.

Above 22k, note that the time to descend can be longer than the time to think. So a backup system and being willing and able to come down really fast need to be thought through beforehand.

RR is right, something happens in the 20's. Perhaps the partial pressure of O2 in the blood and air get close?

[Frank Whiteley]

On Wednesday, October 2, 2019 at 2:02:08 PM UTC-6, wrote:
> https://www.faa.gov/pilots/training/airman_education/media/AC%2061-107A.pdf
>
> Page 13 is the table of useful consciousness versus altitude, and is surrounded by a pretty good discussion.
>
> Above 22k, note that the time to descend can be longer than the time to think. So a backup system and being willing and able to come down really fast need to be thought through beforehand.
>
> RR is right, something happens in the 20's. Perhaps the partial pressure of O2 in the blood and air get close?

This article is quite interesting.
https://www.airspacemag.com/military-aviation/killer-at-70000-feet-117615369/

[waremark]

I have only ever once been above 20k, and on all other occasions have usèd a canula apparently successfully. On that occasion I was planning to go higher and so used the mask which came with my EDS kit. It didn't seal well and I felt I had to keep pressing it against my face. I suggest trying out your equipment in advance of a flight where you expect to go high.

[[email protected]]

Of note:

I was going a good job with my cannula. I kept an eye on my pulse ox, things were going well.

Started eating some trail mix for lunch.... oh yeah, mouth breathing. Pulse Ox was headed south in a hurry.

Just something to think about. I had to be extra vigilant to not stuff my face all at once, and when taking time to drink and eat... consciously make sure to take good hits off the O2 with my nose.

JP

[Maxx Ruff[_2_]]

At 08:09 12 October 2019, wrote:
>Of note:
>
>I was going a good job with my cannula. I kept an eye on my pulse
ox,
>things were going well.
>
>Started eating some trail mix for lunch.... oh yeah, mouth breathing.
>Pulse Ox was headed south in a hurry.
>
>Just something to think about. I had to be extra vigilant to not stuff
my
>face all at once, and when taking time to drink and eat... consciously
make
>sure to take good hits off the O2 with my nose.
>
>JP
>
>
Bought an 'FDA Approved' Finger Pulse Oximeter Blood Oxygen
Saturation SPO2 Heart Rate O2 Patient Monitor from fleabay to try out
($25-ish).

Although it was a bit clunky sitting on the end of my finger, it appeared
to work reliably well on the ground (slight overcast?) or airborne under
cloud.

At altitude it repeatedly failed in very bright sunlight. (Measures light
absorption of the blood in your finger)
Whenever I uncovered my hand in bright sunlight to read the display it
immediately lost the plot. Wonderful!

As an experiment I covered the device and part of my finger in the foil
from a snack bar leaving the display (mostly) uncovered, it worked
much better but was even more inconvenient.

Don't buy cheap??! (YMMV)

MR

[Dan Daly[_2_]]

On Saturday, October 12, 2019 at 7:00:05 AM UTC-4, Maxx Ruff wrote:
> At 08:09 12 October 2019, wrote:
> >Of note:
> >
> >I was going a good job with my cannula. I kept an eye on my pulse
> ox,
> >things were going well.
> >
> >Started eating some trail mix for lunch.... oh yeah, mouth breathing.
> >Pulse Ox was headed south in a hurry.
> >
> >Just something to think about. I had to be extra vigilant to not stuff
> my
> >face all at once, and when taking time to drink and eat... consciously
> make
> >sure to take good hits off the O2 with my nose.
> >
> >JP
> >
> >
> Bought an 'FDA Approved' Finger Pulse Oximeter Blood Oxygen
> Saturation SPO2 Heart Rate O2 Patient Monitor from fleabay to try out
> ($25-ish).
>
> Although it was a bit clunky sitting on the end of my finger, it appeared
> to work reliably well on the ground (slight overcast?) or airborne under
> cloud.
>
> At altitude it repeatedly failed in very bright sunlight. (Measures light
> absorption of the blood in your finger)
> Whenever I uncovered my hand in bright sunlight to read the display it
> immediately lost the plot. Wonderful!
>
> As an experiment I covered the device and part of my finger in the foil
> from a snack bar leaving the display (mostly) uncovered, it worked
> much better but was even more inconvenient.
>
> Don't buy cheap??! (YMMV)
>
> MR

Mine has LEDs and works well. Remember that when you get cold, blood's routed to the core, away from hands/feet, so your reading might be off a bit.

[danlj]

On Saturday, October 12, 2019 at 6:00:05 AM UTC-5, Maxx Ruff wrote:
> Bought an 'FDA Approved' Finger Pulse Oximeter Blood Oxygen
> Saturation SPO2 Heart Rate O2 Patient Monitor from fleabay to try out
> ($25-ish).
>
> Although it was a bit clunky sitting on the end of my finger, it appeared
> to work reliably well on the ground (slight overcast?) or airborne under
> cloud.
>
> At altitude it repeatedly failed in very bright sunlight. (Measures light
> absorption of the blood in your finger)
> Whenever I uncovered my hand in bright sunlight to read the display it
> immediately lost the plot. Wonderful!
>
> As an experiment I covered the device and part of my finger in the foil
> from a snack bar leaving the display (mostly) uncovered, it worked
> much better but was even more inconvenient.
>
> Don't buy cheap??! (YMMV)
>
> MR

Yes. SoaringRx on pulse ox accuracy
https://www.danlj.org/~danlj/Soaring/SoaringRx/2012-06-Pulse-Ox-Accuracy-p18-20-22.pdf
Geez! Hard to believe that I wrote that 7 years ago...
and on high-altitude breathing in general
https://www.danlj.org/~danlj/Soaring/SoaringRx/2018-10-Oxygen-risks.pdf
Enjoy!
DrDan

[danlj]

On Wednesday, October 2, 2019 at 6:17:16 AM UTC-5, Tango Eight wrote:
> On Tuesday, October 1, 2019 at 3:44:11 PM UTC-4, RR wrote:
>
> > The legalitys are not so clear [...]
>
> FAR 23.1447 spells it out (for certificated aircraft). Above 18K the requirement is for a mask that covers nose and mouth.
>
> The fact that some people can get away with a cannula at 26K (once) does not mean that this is a sound practice. We've had two hypoxia incidents (that I know of) at Mt Washington due to pilots emulating certain old timers. Physiology varies. Physical fitness doesn't seem to be a factor (in fact casual observation suggests the reverse :-)).
>
> T8

Yes, this applies to required aircraft equipment, not pilot use under part 91.
BUT -- everyone is different.
There was a study done with *young, fit* pilots showing that the Mtn High canula *could* keep O2 sats above 90% to FL035.
But the older and un-fitter we get, and bearing in mind the large individual differences,
The only safe thing, if you're flying above FL012, is to spend $180 or whatever and buy a good wris****ch-style oximeter and take the reading from a warm finger -- and *verify* that your oxygen supply is at least getting to your finger.
And remember, the normal, physiological hyperventilation of low pressure altitudes can decrease brain perfusion by about 20% while finger perfusion remains normal.
Bottom line: if you feel stupid, you are stupid, and it's time to descend no matter what the oxygen system is doing and no matter what the oximeter says. Been there.
DrDan

[George Haeh]

Dr Dan, Great article on Oxygen hazards, but pages 22 & 23 are missing (possibly a full page ad in there). I have a feeling there's something we should know in the missing page(s).