Oxygen Generators

[JohnDeRosa]

Has anyone investigated the use of an oxygen generator rather than carrying an O2 cylinder?

According to this study from sea level up to 18,000 it seems to work. http://oai.dtic.mil/oai/oai?verb=getRecord&metadataPrefix=html&identifier=ADA371747

"We conclude that from sea level to 18,000', molecular sieve based O2 concentrators are capable of providing medical grade supplemental O2 for at least 8 hours."

Pricey but for those the fly with O2 every day then over the long term it would be cheaper as there would be no refills. Here is a unit for $3K. http://www.emedstores.com/xpo2-portable-oxygen-concentrator-and-free-extra-battery/

Might they be less dangerous in an accident? Is battery power an issue?

- John

[Vaughn]

On 9/23/2013 12:23 PM, JohnDeRosa wrote:
> Pricey but for those the fly with O2 every day then over the long term it would be cheaper
>as there would be no refills.
>Here is a unit for $3K.
http://www.emedstores.com/xpo2-portable-oxygen-concentrator-and-free-extra-battery/


The devil is in the details! But the specks on that unit say 10,000 feet.

These things are mostly made for airline travel. I don't think we've
ever seen more than about 6,000 feet cabin altitude inside an airliner,
(Yes, I travel with an altimeter) so there is little incentive for the
manufacturer to make them work much higher, or even test them at high
altitudes.

My wife needs to travel with oxygen. We have rented several different
Portable Oxygen Concentrators (POCs) with uniformly good results, and
finally bought our own. Assuming pulse oxygen delivery, we get
excellent battery life on trips.

Try before you buy! You can easily rent these units. Fly one with with
a pulse oximeter ($39.99 at Walmart) to verify that it works for you and
to determine your settings. The settings have a big impact on battery life.

Vaughn

[Bob Kuykendall]

On Monday, September 23, 2013 9:23:44 AM UTC-7, JohnDeRosa wrote:
> Has anyone investigated the use of an oxygen generator rather than
> carrying an O2 cylinder?

The late Les Sebald carried a chemical oxygen generator of the type used on airliners as a backup oxygen source in his HP-14. He worked for United Airlines, and I imagine that he had access to expired units that were out of date but probably still good. I remember seeing that Les's O2 generator was carefully mounted so that the airframe was protected from the rather high heat generated as a byproduct of the chemical reaction that produced the oxygen.

Thanks, Bob K.

[Eric Greenwell[_4_]]

JohnDeRosa wrote, On 9/23/2013 9:23 AM:
> Has anyone investigated the use of an oxygen generator rather than
> carrying an O2 cylinder?
>
> According to this study from sea level up to 18,000 it seems to work.
> http://oai.dtic.mil/oai/oai?verb=getRecord&metadataPrefix=html&identifier=ADA371747
>
> "We conclude that from sea level to 18,000', molecular sieve based
> O2 concentrators are capable of providing medical grade supplemental
> O2 for at least 8 hours."
>
> Pricey but for those the fly with O2 every day then over the long
> term it would be cheaper as there would be no refills. Here is a
> unit for $3K.
> http://www.emedstores.com/xpo2-portable-oxygen-concentrator-and-free-extra-battery/
>
> Might they be less dangerous in an accident? Is battery power an
> issue?

Not a cost saver for glider pilots that fill their own bottles. I can
fill my 14 cf bottle for $5 from my welding bottle, then get 12 hours
off of it. It would take a lot of refills to pay for the $3000 unit.

I haven't heard of ox cylinders being a danger in glider accidents, so I
don't think the ox generator would help any.

I suspect it might not work well in flights where the cockpit
temperature goes below freezing, but did not look into it.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)
- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm
http://tinyurl.com/yb3xywl

[JohnDeRosa]

On Monday, September 23, 2013 12:56:34 PM UTC-5, Vaughn wrote:
> Fly one with with a pulse oximeter ($39.99 at Walmart) to verify that it works for you...
>
> Vaughn

Actually only $35 at Walmart.

http://www.walmart.com/ip/Choicemmed-Oxywatch-Fingertip-Pulse-Oximeter-1ct/17325061

[Dan Marotta]

Working as a tow pilot for a commercial operation, I get my oxygen for free.

As to a danger in a crash, when my partner crashed our LS-6a, the O2 bottle
mounted behind his left arm broke loose and made quite a gash in the back of
his arm just above the elbow.


"Eric Greenwell" > wrote in message
...
> JohnDeRosa wrote, On 9/23/2013 9:23 AM:
>> Has anyone investigated the use of an oxygen generator rather than
>> carrying an O2 cylinder?
>>
>> According to this study from sea level up to 18,000 it seems to work.
>> http://oai.dtic.mil/oai/oai?verb=getRecord&metadataPrefix=html&identifier=ADA371747
>>
>> "We conclude that from sea level to 18,000', molecular sieve based
>> O2 concentrators are capable of providing medical grade supplemental
>> O2 for at least 8 hours."
>>
>> Pricey but for those the fly with O2 every day then over the long
>> term it would be cheaper as there would be no refills. Here is a
>> unit for $3K.
>> http://www.emedstores.com/xpo2-portable-oxygen-concentrator-and-free-extra-battery/
>>
>> Might they be less dangerous in an accident? Is battery power an
>> issue?
>
> Not a cost saver for glider pilots that fill their own bottles. I can fill
> my 14 cf bottle for $5 from my welding bottle, then get 12 hours off of
> it. It would take a lot of refills to pay for the $3000 unit.
>
> I haven't heard of ox cylinders being a danger in glider accidents, so I
> don't think the ox generator would help any.
>
> I suspect it might not work well in flights where the cockpit temperature
> goes below freezing, but did not look into it.
>
> --
> Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
> email me)
> - "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm
> http://tinyurl.com/yb3xywl

[Bill D]

Anybody look at those small liquid oxygen medical packs you see ambulatory patients wearing?

[Dan Marotta]

What have you guys got against a proper oxygen system?

All these quotations of the FARs, and electronic collision avoidance,
navigation, etc., and you want to skimp on BREATHING???

"Bill D" > wrote in message
...
> Anybody look at those small liquid oxygen medical packs you see ambulatory
> patients wearing?

[Bill D]

On Tuesday, September 24, 2013 10:41:31 AM UTC-6, Dan Marotta wrote:
> What have you guys got against a proper oxygen system?
>

1. Size
2. Weight

Especially in 2-seaters, a decent sized compressed O2 system eats into the allowable cockpit payload and often takes up space the pilot would rather use for something else.

[Dan Marotta]

Agreed, but is there anything *legal* that suits your needs and yet is
certified above 10,000'? You don't really need O2 below that.

How about something proper, that's really small (fits behind the seat, etc.,
is easily removeable, and can be filled after each flight?

"Bill D" > wrote in message
...
> On Tuesday, September 24, 2013 10:41:31 AM UTC-6, Dan Marotta wrote:
>> What have you guys got against a proper oxygen system?
>>
>
> 1. Size
> 2. Weight
>
> Especially in 2-seaters, a decent sized compressed O2 system eats into the
> allowable cockpit payload and often takes up space the pilot would rather
> use for something else.

[Bill D]

On Wednesday, September 25, 2013 8:12:40 AM UTC-6, Dan Marotta wrote:
> Agreed, but is there anything *legal* that suits your needs and yet is
>
> certified above 10,000'? You don't really need O2 below that.
>
>
>
> How about something proper, that's really small (fits behind the seat, etc.,
>
> is easily removeable, and can be filled after each flight?
>
>
>
> "Bill D" > wrote in message
>
> ...
>
> > On Tuesday, September 24, 2013 10:41:31 AM UTC-6, Dan Marotta wrote:
>
> >> What have you guys got against a proper oxygen system?
>
> >>
>
> >
>
> > 1. Size
>
> > 2. Weight
>
> >
>
> > Especially in 2-seaters, a decent sized compressed O2 system eats into the
>
> > allowable cockpit payload and often takes up space the pilot would rather
>
> > use for something else.

I think any portable O2 system is "legal".

I've searched the FAR's without finding mention of Oxygen other than 91.211, 121.333, 121.237 and 135.89 which just spell out when a flight crew has to use it.

The AOPA has a good article at:
http://www.aopa.org/Pilot-Resources/PIC-archive/Pilot-and-Passenger-Physiology/Oxygen-Use-in-Aviation
I like the part which says "oxygen is oxygen" and the use of ABO or some other source is "at the operators discretion".

LOX systems are "use it or lose it" since it eventually boils off whereas compressed O2 systems can set almost forever without losing pressure. There has to be a convenient way for patients who need LOX all the time to get refills.

[Richard[_9_]]

On Monday, September 23, 2013 9:23:44 AM UTC-7, JohnDeRosa wrote:
> Has anyone investigated the use of an oxygen generator rather than carrying an O2 cylinder?
>
>
>
> According to this study from sea level up to 18,000 it seems to work. http://oai.dtic.mil/oai/oai?verb=getRecord&metadataPrefix=html&identifier=ADA371747
>
>
>
> "We conclude that from sea level to 18,000', molecular sieve based O2 concentrators are capable of providing medical grade supplemental O2 for at least 8 hours."
>
>
>
> Pricey but for those the fly with O2 every day then over the long term it would be cheaper as there would be no refills. Here is a unit for $3K. http://www.emedstores.com/xpo2-portable-oxygen-concentrator-and-free-extra-battery/
>
>
>
> Might they be less dangerous in an accident? Is battery power an issue?
>
>
>
> - John

A couple of good articles on O2 from Mountain High.

http://www.craggyaero.com/O2main.htm

O2 can be purchase at many industrial gas outlets and is relatively inexpensive. ABO is the same as welding O2 but usually is a little more expensive and comes in a bottle marked ABO. Large bottles have the downside that you usually have to rent them and you need a transfill system to fill the glider bottles. If you take your glider bottle to the outlet they will check the test date on the bottle, if out of date they probably will not fill it, so be aware. The bottle test date is not an FAA requirement. It is regulated by the DOT.

Richard
www.craggyaero.com

[Bill D]

On Wednesday, September 25, 2013 11:18:36 AM UTC-6, Richard wrote:
> On Monday, September 23, 2013 9:23:44 AM UTC-7, JohnDeRosa wrote:
>
> > Has anyone investigated the use of an oxygen generator rather than carrying an O2 cylinder?
>
> >
>
> >
>
> >
>
> > According to this study from sea level up to 18,000 it seems to work. http://oai.dtic.mil/oai/oai?verb=getRecord&metadataPrefix=html&identifier=ADA371747
>
> >
>
> >
>
> >
>
> > "We conclude that from sea level to 18,000', molecular sieve based O2 concentrators are capable of providing medical grade supplemental O2 for at least 8 hours."
>
> >
>
> >
>
> >
>
> > Pricey but for those the fly with O2 every day then over the long term it would be cheaper as there would be no refills. Here is a unit for $3K. http://www.emedstores.com/xpo2-portable-oxygen-concentrator-and-free-extra-battery/
>
> >
>
> >
>
> >
>
> > Might they be less dangerous in an accident? Is battery power an issue?
>
> >
>
> >
>
> >
>
> > - John
>
>
>
> A couple of good articles on O2 from Mountain High.
>
>
>
> http://www.craggyaero.com/O2main.htm
>
>
>
> O2 can be purchase at many industrial gas outlets and is relatively inexpensive. ABO is the same as welding O2 but usually is a little more expensive and comes in a bottle marked ABO. Large bottles have the downside that you usually have to rent them and you need a transfill system to fill the glider bottles. If you take your glider bottle to the outlet they will check the test date on the bottle, if out of date they probably will not fill it, so be aware. The bottle test date is not an FAA requirement. It is regulated by the DOT.
>
>
>
> Richard
>
> www.craggyaero.com

A counter guy once showed me how a bottle of O2 gets the ABO sticker. If the rube at the counter asks for "aviation oxygen" he grabbed a sticker on the way to the warehouse and slapped it on the first O2 cylinder he found. In their computer the SKU for "aviation oxygen" differed from the one for welding oxygen only in price. $112 for ABO and $25 for welding O2.

[Dan Marotta]

FAR 91.211 <No person may operate blah, blah, blah>
(3) At cabin pressure altitudes above 15,000 feet (MSL) unless **each
occupant** of the aircraft is provided with supplemental oxygen.

Passengers are occupants.


"Bill D" > wrote in message
...
> On Wednesday, September 25, 2013 8:12:40 AM UTC-6, Dan Marotta wrote:
>> Agreed, but is there anything *legal* that suits your needs and yet is
>>
>> certified above 10,000'? You don't really need O2 below that.
>>
>>
>>
>> How about something proper, that's really small (fits behind the seat,
>> etc.,
>>
>> is easily removeable, and can be filled after each flight?
>>
>>
>>
>> "Bill D" > wrote in message
>>
>> ...
>>
>> > On Tuesday, September 24, 2013 10:41:31 AM UTC-6, Dan Marotta wrote:
>>
>> >> What have you guys got against a proper oxygen system?
>>
>> >>
>>
>> >
>>
>> > 1. Size
>>
>> > 2. Weight
>>
>> >
>>
>> > Especially in 2-seaters, a decent sized compressed O2 system eats into
>> > the
>>
>> > allowable cockpit payload and often takes up space the pilot would
>> > rather
>>
>> > use for something else.
>
> I think any portable O2 system is "legal".
>
> I've searched the FAR's without finding mention of Oxygen other than
> 91.211, 121.333, 121.237 and 135.89 which just spell out when a flight
> crew has to use it.
>
> The AOPA has a good article at:
> http://www.aopa.org/Pilot-Resources/PIC-archive/Pilot-and-Passenger-Physiology/Oxygen-Use-in-Aviation
> I like the part which says "oxygen is oxygen" and the use of ABO or some
> other source is "at the operators discretion".
>
> LOX systems are "use it or lose it" since it eventually boils off whereas
> compressed O2 systems can set almost forever without losing pressure.
> There has to be a convenient way for patients who need LOX all the time to
> get refills.

[[email protected]]

On Monday, September 23, 2013 2:39:28 PM UTC-8, JohnDeRosa wrote:
> On Monday, September 23, 2013 12:56:34 PM UTC-5, Vaughn wrote: > Fly one with with a pulse oximeter ($39.99 at Walmart) to verify that it works for you... > > Vaughn Actually only $35 at Walmart. http://www.walmart.com/ip/Choicemmed-Oxywatch-Fingertip-Pulse-Oximeter-1ct/17325061

Pulse oximeters are poor indicators of O2 saturation for glider pilots. Peripheral (as in fingers)vaso-constriction is common at the temperature and altitudes we fly. I used one for a few years and was over consuming Oxygen in an effort to keep the saturation above 95%. I use a EDS delivery system and consistantly got values of around 86% when above 6000 feet. I actually went to a Pulmonologist to see what, if anything, was wrong with my lungs and found that my lung capacity and ventilation were above normal. So I tossed out the oximeter and just trust the equipment to deliver the right amount of O2. So far so good.

[Eric Greenwell[_4_]]

wrote, On 9/26/2013 12:10 PM:
> On Monday, September 23, 2013 2:39:28 PM UTC-8, JohnDeRosa wrote:
>> On Monday, September 23, 2013 12:56:34 PM UTC-5, Vaughn wrote: >
>> Fly one with with a pulse oximeter ($39.99 at Walmart) to verify
>> that it works for you... > > Vaughn Actually only $35 at Walmart.
>> http://www.walmart.com/ip/Choicemmed-Oxywatch-Fingertip-Pulse-Oximeter-1ct/17325061
>
>>
> Pulse oximeters are poor indicators of O2 saturation for glider
> pilots. Peripheral (as in fingers)vaso-constriction is common at the
> temperature and altitudes we fly. I used one for a few years and was
> over consuming Oxygen in an effort to keep the saturation above 95%.
> I use a EDS delivery system and consistantly got values of around 86%
> when above 6000 feet. I actually went to a Pulmonologist to see
> what, if anything, was wrong with my lungs and found that my lung
> capacity and ventilation were above normal. So I tossed out the
> oximeter and just trust the equipment to deliver the right amount of
> O2. So far so good.

Since I can keep O2 saturation above 95% at even 18000' using the normal
EDS settings, does that mean I have excellent circulation? Or really
good lung function?

It does drop into the 90-95% range sometimes, but that's also when I
realize my breathing is very shallow; i.e., I don't seem to be inhaling
very much after I hear the "poosh" of the EDS oxygen pulse.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)
- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm
http://tinyurl.com/yb3xywl

[[email protected]]

That's amazing at your age Eric. Probably a defective oximeter.

[Eric Greenwell[_4_]]

wrote, On 9/27/2013 9:57 AM:
> That's amazing at your age Eric. Probably a defective oximeter.

I have an expensive, older Minolta and a much newer cheapie, but they
read quite close together. I'll take them both along next time for a
better comparison.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)
- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm
http://tinyurl.com/yb3xywl

[son_of_flubber]

On Thursday, September 26, 2013 11:49:23 PM UTC-4, Eric Greenwell wrote:
> Since I can keep O2 saturation above 95% at even 18000' using the normal
> EDS settings, does that mean I have excellent circulation? Or really
> good lung function?
>

It could also mean that you breathing too rapidly or deeply (mild hyperventilating). Hyperventilation will dilate your finger blood vessels and RAISE the pulse oximeter saturation number. And hyperventilation will simultaneously constrict your cerebral blood vessels, and thereby LOWER the O2 saturation of the blood going to your brain (thereby inducing mild hypoxia). Vasodilation may also lower the temperature of your core and induce the mental dulling effects of mild hypothermia.

See http://www.danlj.org/~danlj/Soaring/SoaringRx/2012-06-Pulse-Ox-Accuracy-p18-20-22.pdf

> It does drop into the 90-95% range sometimes, but that's also when I
> realize my breathing is very shallow; i.e., I don't seem to be inhaling
> very much after I hear the "poosh" of the EDS oxygen pulse.

If you're making any conscious effort to "breath", you may be mildly hyperventilating.

A common way to breath at the correct rate is to talk (or sing) out loud, this distracts you from thinking about your respiration rate. The autonomic nervous system works best without conscious or emotional intervention.

[Eric Greenwell[_4_]]

son_of_flubber wrote, On 9/29/2013 4:47 PM:
> On Thursday, September 26, 2013 11:49:23 PM UTC-4, Eric Greenwell
> wrote:
>> Since I can keep O2 saturation above 95% at even 18000' using the
>> normal EDS settings, does that mean I have excellent circulation?
>> Or really good lung function?
>>
>
> It could also mean that you breathing too rapidly or deeply (mild
> hyperventilating). Hyperventilation will dilate your finger blood
> vessels and RAISE the pulse oximeter saturation number. And
> hyperventilation will simultaneously constrict your cerebral blood
> vessels, and thereby LOWER the O2 saturation of the blood going to
> your brain (thereby inducing mild hypoxia). Vasodilation may also
> lower the temperature of your core and induce the mental dulling
> effects of mild hypothermia.
>
> See
> http://www.danlj.org/~danlj/Soaring/SoaringRx/2012-06-Pulse-Ox-Accuracy-p18-20-22.pdf
>
>
>> It does drop into the 90-95% range sometimes, but that's also when
>> I realize my breathing is very shallow; i.e., I don't seem to be
>> inhaling very much after I hear the "poosh" of the EDS oxygen
>> pulse.
>
> If you're making any conscious effort to "breath", you may be mildly
> hyperventilating.
>
> A common way to breath at the correct rate is to talk (or sing) out
> loud, this distracts you from thinking about your respiration rate.
> The autonomic nervous system works best without conscious or
> emotional intervention.

I wonder if there might be a training effect from the "poosh" of the EDS
system, such that a pilot tends to stop inhaling sooner than he
otherwise would.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)

[son_of_flubber]

Question to clarify how EDS works: I assume that the pilot controls the respiration rate and that inhaling triggers the release of O2 from the EDS.

On Sunday, September 29, 2013 11:04:56 PM UTC-4, Eric Greenwell wrote:

> I wonder if there might be a training effect from the "poosh" of the EDS
> system, such that a pilot tends to stop inhaling sooner than he
> otherwise would.

I can imagine that EDS might train a pilot to take MORE SHALLOW breathes, but the body's autonomic system would then detect an imbalance and prompt the pilot to take MORE FREQUENT breathes in order to establish proper O2 (and CO2) blood levels. Conscious breathing disrupts the autonomic regulation process.

If your pulse oximeter reads low, then turn up the O2 delivery rate or descend. Do you use Aerox Silicone mask or similar with EDS above 18000?

[Morgans[_2_]]

> wrote in message
...
> That's amazing at your age Eric. Probably a defective oximeter.

Also could be that he has reinoids syndrome (sp?) or something , which
causes the blood flow to the fingers to be almost completely cut off when
the fingers get cold, and they get cold very easily with this condition.

Try hooking the sensor up to your ear lobe. Really.

Jim in NC

[Evan Ludeman[_4_]]

On Thursday, September 26, 2013 11:49:23 PM UTC-4, Eric Greenwell wrote:
> wrote, On 9/26/2013 12:10 PM:
>
> > On Monday, September 23, 2013 2:39:28 PM UTC-8, JohnDeRosa wrote:
>
> >> On Monday, September 23, 2013 12:56:34 PM UTC-5, Vaughn wrote: >
>
> >> Fly one with with a pulse oximeter ($39.99 at Walmart) to verify
>
> >> that it works for you... > > Vaughn Actually only $35 at Walmart.
>
> >> http://www.walmart.com/ip/Choicemmed-Oxywatch-Fingertip-Pulse-Oximeter-1ct/17325061
>
> >
>
> >>
>
> > Pulse oximeters are poor indicators of O2 saturation for glider
>
> > pilots. Peripheral (as in fingers)vaso-constriction is common at the
>
> > temperature and altitudes we fly. I used one for a few years and was
>
> > over consuming Oxygen in an effort to keep the saturation above 95%.
>
> > I use a EDS delivery system and consistantly got values of around 86%
>
> > when above 6000 feet. I actually went to a Pulmonologist to see
>
> > what, if anything, was wrong with my lungs and found that my lung
>
> > capacity and ventilation were above normal. So I tossed out the
>
> > oximeter and just trust the equipment to deliver the right amount of
>
> > O2. So far so good.
>
>
>
> Since I can keep O2 saturation above 95% at even 18000' using the normal
>
> EDS settings, does that mean I have excellent circulation? Or really
>
> good lung function?
>
>
>
> It does drop into the 90-95% range sometimes, but that's also when I
>
> realize my breathing is very shallow; i.e., I don't seem to be inhaling
>
> very much after I hear the "poosh" of the EDS oxygen pulse.
>
>
>
> --
>
> Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
>
> email me)
>
> - "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm
>
> http://tinyurl.com/yb3xywl

I think it probably means you are in good health and have good equipment and procedures.

I've experience hyperventilation induced hypoxia. You will feel horrible. Tingling extremities, headache, and yeah... a fingertip pulse ox reading of 92 - 95%.

Unmentioned so far... hypoxia comes with tachycardia. So when you see 92%+ saturation but 110 - 120 pulse rate, there's your confirmation. If you have a decent quality (e.g. Nonin) pulse ox, you see a strong pulse indication, high saturation, pulse below 90 and you feel normal and alert, you are doing it right.

-Evan Ludeman / T8

[Mike J.]

On Monday, September 30, 2013 10:32:02 AM UTC-5, Morgans wrote:
> > wrote in message ... > That's amazing at your age Eric. Probably a defective oximeter. Also could be that he has reinoids syndrome (sp?) or something , which causes the blood flow to the fingers to be almost completely cut off when the fingers get cold, and they get cold very easily with this condition. Try hooking the sensor up to your ear lobe. Really. Jim in NC

I believe the condition you are referring to is "Raynaud's Phenomenon". And you're right .... it can/does restrict blood flow to some finger tips due to stress and/or cold. Finger tips could even turn blue.

[[email protected]]

if you have a tendency to cold hands, that means that your perfusion to the extremity is poorer. Not necessarily a problem but your 02 sat will read lower than your core saturations. this can happen even at sea level.

Mark J

[Eric Greenwell[_4_]]

son_of_flubber wrote, On 9/30/2013 6:20 AM:
> Question to clarify how EDS works: I assume that the pilot controls
> the respiration rate and that inhaling triggers the release of O2
> from the EDS.
>
> On Sunday, September 29, 2013 11:04:56 PM UTC-4, Eric Greenwell
> wrote:
>
>> I wonder if there might be a training effect from the "poosh" of
>> the EDS system, such that a pilot tends to stop inhaling sooner
>> than he otherwise would.
>
> I can imagine that EDS might train a pilot to take MORE SHALLOW
> breathes, but the body's autonomic system would then detect an
> imbalance and prompt the pilot to take MORE FREQUENT breathes in
> order to establish proper O2 (and CO2) blood levels. Conscious
> breathing disrupts the autonomic regulation process.
>
> If your pulse oximeter reads low, then turn up the O2 delivery rate
> or descend. Do you use Aerox Silicone mask or similar with EDS above
> 18000?

The pilot does control his respiration rate while using an EDS, but the
EDS will not deliver an oxygen pulse if the next inhalation occurs too
soon; i.e., it limits the maximum rate at which it will deliver oxygen
pulses.

It's been 15 years or so (pre-oximeter availability) since I went above
18,000', but I always used a cannula with EDS, never a mask. I would
ocasionally increase the flow (double or more), but never noticed any
change in how I felt or my thinking, even after several minutes, so I
assumed I was getting sufficient oxygen.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)

[Eric Greenwell[_4_]]

Evan Ludeman wrote, On 9/30/2013 9:15 AM:
> On Thursday, September 26, 2013 11:49:23 PM UTC-4, Eric Greenwell
> wrote:

>>
>>
>> Since I can keep O2 saturation above 95% at even 18000' using the
>> normal
>>
>> EDS settings, does that mean I have excellent circulation? Or
>> really
>>
>> good lung function?
>>
>>
>>
>> It does drop into the 90-95% range sometimes, but that's also when
>> I
>>
>> realize my breathing is very shallow; i.e., I don't seem to be
>> inhaling
>>
>> very much after I hear the "poosh" of the EDS oxygen pulse.


> I think it probably means you are in good health and have good
> equipment and procedures.
>
> I've experience hyperventilation induced hypoxia. You will feel
> horrible. Tingling extremities, headache, and yeah... a fingertip
> pulse ox reading of 92 - 95%.
>
> Unmentioned so far... hypoxia comes with tachycardia. So when you
> see 92%+ saturation but 110 - 120 pulse rate, there's your
> confirmation. If you have a decent quality (e.g. Nonin) pulse ox,
> you see a strong pulse indication, high saturation, pulse below 90
> and you feel normal and alert, you are doing it right.

My pulse rate is always under 90, and normally under 80, except
sometimes for the first few minutes after shutting off the engine.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)

[Peter Purdie[_3_]]

If you are going to use an EDS system, then you need to know how it is
meant to work (and from some of the comments on the thread clearly some
posters don't).

The EDS system gives a pulse of O2 at the beginning of the breathing cycle,
the length of the pulse depends on the ambient pressure. When you inhale,
the oxygen used by the lungs is taken from the air that ends up down there
any oxygen in the upper respiratory tract is unused and breathed out.

If you stop inhaling at the end of the pulse ('shallow breathing') then the
oxygen at the end of the pulse is wasted, it never gets down to the lungs.
The EDS box doesn't know that so you are under delivering useful oxygen.

Constant flow systems enrich all the air in the system, so 50% plus of the
oxygen you pay for is wasted.

You need to be aware of the need to breathe normally. I have used EDS with
cannula up to 24,000ft or so without issues. I have had an altitude
chamber run so I can recognise the symptoms of anoxia (yes, I know it can
creep up on you).

[Evan Ludeman[_4_]]

> I have gotten away with using EDS with
>
> cannula up to 24,000ft or so without issues. I have had an altitude
>
> chamber run so I can recognise the symptoms of anoxia (yes, I know it can
>
> creep up on you).


Fixed it for you. Sorry, hot button issue. I am aware of pilots having flown the EDS/cannula system to around 27K, once or twice. That doesn't mean it's something we ought to brag about. The guy that did that has since smartened up, uses an EDS mask above 18K, has a nice constant flow backup system in place.

On constant flow, use of a mask above 18K is even more important. You probably can achieve good oxygen saturation on a constant flow cannula at 25K, but the flow rate will have to be high to do it (several liters/minute). Misleading advertising aside, a good quality rebreather mask is a far more efficient delivery device than a "pink mustache".

Evan Ludeman (Mt Wash Wave Camp Ox Nag)