The EDS (Electronic oxygn Delivery System) is a single
person aviation oxygen delivery system designed to maximize
the administration of oxygen in the most efficient way. The
breathing cycle of a healthy, non-smoking person is such that
about one-third is spent inhaling while two-thirds is exhaling
and pausing. In addition, the lungs of most mammals are an
organ of relative inefficiency compared to the other life-
support organs. This is partly because only a fraction of
inhaled air actually gets to the oxygen absorbing alveolar of
the lungs. The rest is spent in the so-called dead-spaces, i.e.
trachea, bronchus, and other areas where there are no alveolar
allowing oxygen exchange. Therefore, you would benefit
mostly from oxygen delivered at the very beginning of
inhalation cycles as it leads deep into the most functional part
of the lungs, allowing optimum oxygen absorption, thus,
needing less. The EDS monitors micro-pressure changes from
your breathing, delivering a precise pulse of oxygen at the
instant each inhaling cycle is detected and not during
exhalation, pausing or talking, etc.
The EDS "synchronous inhalation pulsing technique" is the
most efficient way known by respiratory physiologists to
saturate the blood to well over 94% while using as little as one-
tenth the oxygen of constant flow systems. Actual field tests
with powerless soaring flights have yielded savings of over
ten times. The EDS utilizes these well known physiological
facts (research data is available upon request) providing the
smallest, lightest yet most efficient aviation oxygen system
available. Precious oxygen is simply wasted with constant
The main objective of the EDS was to provide an improvement
in oxygen conservation, allowing a smaller and lighter oxygen
system, allowing existing cylinders to last longer or to allow
smaller cylinders to last as long as larger ones. Other objectives
were to have a system that provides a constant bolus volume at
any respiration rate [that is in the norm] and make it truly
automatic and self-compensating with varying altitudes. The
EDS unit synchronizes itself to your respiration rate, responding
to normal breathing and generally not to fluctuations caused by
talking etc., therefore, saving oxygen for only every deliberate
breath. The EDS delivers the full and accurately measured bolus
for that pressure altitude regardless of the respiration rate.
The EDS is calibrated to deliver a 41 ml. bolus at a standard
pressure altitude (spa) of 18,000 ft. This bolus volume is
accurate at respiration rates up to 20/min. At a standard pressure
altitude of 12,000 ft., the EDS delivers a bolus volume of 26 ml.
calculated and tested to produce well over 90% SaO2. This is
considering an average respiration rate of about 14 breaths per
minute. This calibration is about 20% more than the 1.0
liter/min. per 10,000 ft. requirement detailed by the FAA.
Standard Pressure Altitude (spa.) is an asymptotic (never quite
getting to zero) pressure lapse rate curve that starts at sea-level
and lowers towards a partial pressure representing some very
high altitude i.e. 100,000 ft. The spa. curve assumes that at sea-
level the barometric pressure is 29.921 in. Hg. (14.70 psi.) with a
temperature of 15.0° C (59° F). and the standard temperature
lapse of 2.0° C per/1,000 ft. (304.8 meters). In the real world the
temperature and pressure vary constantly at any given altitude
and point in the atmosphere, thus producing weather. The
reasons for the spa. term are that the performance and efficiency
of the human body respond directly to variations in the spa.
Therefore, the barometer in the EDS responds to both absolute
pressure and temperature, as do the physiological properties of
your body, to produce correct deliveries automatically at any
(pressure) altitude.
The EDS has been designed with a tremendous amount of care
and adjustability in calibration. Therefore, if you would like the
"D" mode to commence operations at another altitude, your EDS
unit can be recalibrated. The range is from 2,000 ft. to 13,000 ft.
The EDS unit commences operation at a pressure altitude of
11,500 ft., the recommended starting point for sport and general
aviation. The FAA requires commercial aviation pilots to start
using oxygen at 10,000 ft. If you feel that you need more
oxygen, you can press the battery test button to get a full flow of
oxygen for the duration of the button being pressed. The EDS is
a true on-demand system responding to each and every breath
you demand, from 20/minute (once every 3 seconds) or as little
as none. Therefore, the amount of oxygen savings will be a
direct function of your demands. See EDS worst-case
performance tables appendix for time data while using nasal
cannula and face mask.
The EDS has been designed and tested to
operate and saturate a persons blood with
oxygen to levels well over 90% at pressure
altitudes of 25,000 ft. while using the cannula.
The delivery pulse length is determined by a built-in, precision
temperature-compensated barometer calibrated to measure
density (pressure) altitude. Higher altitudes make longer
pulses, automatically compensating with altitude and
temperature changes. Longer pulses yield greater bolus
volumes. There are no dials to observe nor knobs to turn as
you climb or descend. For general aviation the EDS can be
set to 'D' (Day or Delayed) mode where it will not respond to
your breathing until it senses altitudes around 11,500 ft. (+-
500 ft.) saving oxygen below altitudes where it is not needed
during daylight flight operations. It can be set to 'N' (Night or
Now) mode for night flying where it will respond through all
altitudes. Adjustment, or zeroing, the built-in barometer for
new barometric pressures or flying sites is not needed because
the EDS responds directly to density altitude as do the
physiological properties of your body. The EDS is a truly
automatic on-demand oxygen delivery system.
Pause
Inhalation
Exhalation
Pulse volume
at 8,000 ft.
Pulse volume
at 18,000 ft.
on
o f f
Approximate scales
Pressure Altitude.
Thousand feet
'D' mode
starts here
O2 Pulse units
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Typical
Pressure
Altitude
response
curve
