(a

mensions and a moderate increase in weight, the
device could be adapted for use by larger chil-
dren and possibly even adults. The capability
of the IFD to fulfill each of the above require-
ments was tested and evaluated as follows,

1. Buoyancy, stability and self-righting: A
series of field tests was carried out using an
anthropomorphic dummy, representative of a
38-year-old child. Since small infant anthropo-

morphic dummies were not available, dolls were
obtained and modified such as to exhibit body
weight and centers of gravity of children 4
months to 214 years of age. Using these dum-
mies, stability and seaworthiness of the IFD
were evaluated under a variety of wind and wave
conditions. Tests of self-righting and impact

integrity were carried out by dropping the IFD
(occupied by a dummy) into water from various
heights and release attitudes.

‘Ficurx 2. Photograph of infant flotation device occupied by a baboon.

Tanyard to the left supports intravenous

and continuous carbon dioxide sampling tubes.

3



REFERENCES
1. Beckman, E. L.: Thermal Protection During Immer- 4. Gilbert P. W.: Report on the Use of the Johnson
sion in Cold Water, Proceedings, Second Symposium Shark Sereen as a Deterrent to Sharks. U.S. Naval
on Underwater Physiology, National Academy of Ordnance ‘Test Station, W. O. PO 60530/5000¥0944-66,
Sciences, National Research Council, Washington, Div. of Biology, Cornell Univ., Ithaca, N. Y., Nov. 1,
D.C., Publication 1181, 1963. : 1986.
2, Smith, ©. A.: The Physiology of the Newborn Infant, — © an * a & ae Nelson And &. 7 aren
1 of N ‘Ss harl errent Device. S. Naval rd~
hind Editi 6. 30. eld, . US.
i, ee Charles C. Thomas Co. Springfi nanee Test Station, W. ©. PO 60530/5000¥0943-66,
” . Univ. of Hawaii, Honolulu, Hawaii, Aug. 15, 1966.
8. McFadden, E. B. J. M. Simpson and D. TL. Wolfens- — ¢, swearingen, J. J. and J. W. Young: Determination
j parger: Protection of Infants in Aircraft Ditching, of Centers of Gravity of Children Sitting and Stand-
H published in the preprints of the Aerospace Medical ing, FAA Office of Aviation Medicine Report No.
Association Meeting, 6 May 1968, Miami Beach, Fla. AM 63-23, Aug. 1065.
i
1
i ‘ .
/
y :
-
»
| &
i

7



ted excellent
taining the
of attitudes.
ion, the center
ends to right

by variation in

&

and increased wind and wave conditions. An-
esthetized primates (baboons) exhibiting body
weights and metabolic activity (CO, production
and QO, consumption) equivalent to that of a
small child were utilized in these experiments.
A tranquilized (8 mg./Kg. Sernalyn®) baboon
was seated in the IFD, the canopy secured, and
the IFD placed in an indoor pool. (Figure 2)

For the extended anesthesia desired in these ex-
periments, Pentobarbital Sodium was adminis-
tered intravenously as required. A wavemaker

was designed and constructed in order to produce
a variety of wave conditions, (Figure 3) Vari-
able speed fans and accurate wind velocity meas-
uring equipment were utilized to produce air
movement. Carbon dioxide concentration within
the device was continuously monitored by passing
a sample of air from the IFD through a Beckman
Spinco LB~1 Medical Gas Analyzer and return-
ing it unchanged by analysis to the IFD. (Fig-
ure 4) In an evaluation of the ventilatory

Figure 4. Apparatus for continuously monitoring and recording carbon dioxide accumulation within the infant
flotation device.

5



As measured by a Dillon underwater load cell,
the total buoyancy of the IFD approximates 46
pounds. This is approximately twice the buoy-
ancy of the inflatable vest carried by the airlines.
Adequate buoyancy and stability is provided by
the remaining compartment in case of failure of
either compartment. The stability by reason of
the location of the center of gravity has been
shown by test to be excellent in smooth and rough
water.?® Water impact tests carried out from

(Froude 3. Photograph of wave generator. Frequency and amplitude of waves are controlled by variation in

cliffs 18 to 21 feet in height indicated excellent
self-righting when the IFD containing the
dummy was released in a variety of attitudes.
When released in the inverted position, the center
of gravity is such that the IFD tends to right
itself before entry into the water.

2. Ventilation and carbon diowide accumula-
tion: Carbon dioxide accumulation and ventila-
tion of the IFD were studied under minimal

speed and stroke of the apparatus.

and
esthi
weig
and
smal
Ati
was
the
For
perit
terec

Frovrt



not possible,
ble increase
time may be
may be de-
net in a life
‘D provides

] portions of
receive some
the inflatable
would fune-
designs for
ry minimiza-

; It has been
and reflectiv-
have some
ing attack by
of a baglike
n and known
indicate that,
size and in-
human form
rks in captiv-

‘

movement, and a

&

Prototypes of the IFD incorporating black,
non-reflective and brightly-colored immersed sur-
faces were fabricated. However, the IFD design
differs from the shark screen in that the immersed
portion is much smaller and, due to thermal and
ventilatory design considerations, does not com-
pletely conceal the configuration of the child
occupying the device. Each of these IFD’s oc-
eupied by an anthropomorphic child dummy or
primate was repeatedly exposed to captive coastal
and bottom feeding sharks in the Mote Marine
Laboratory shark pens, Siesta Key, Florida.
Species used in these experiments included brown.
sharks (carcharkinus milberti), tiger sharks
(gdeocerdo cwieri) and bull sharks (carchar-
hinus leucas ), all of which are known to be dan-
gerous to man. As a control, anthropomorphic
dummies, wearing standard inflatable life jackets
only, were introduced into the shark pen con-
currently with the IFD’s. Reaction of the sharks
was recorded by surface and underwater motion

picture cameras operated by divers utilizing
SCUBA equipment.

Tests of the shark deterrency of the IFD
carried out at the Mote Marine Laboratory indi-
cated that the IFD was less attractive to sharks
than an anthropomorphic dummy in a standard
life vest. The sharks used in the testing program
were noticeably more active and aggressive at
night, especially toward the anthropomorphic
dummy equipped with the life vest. Their initial
reaction to the IFD containing the tranquilized
baboon was to congregate in the opposite end of
the shark pen and avoid the animal. Previous
studies have indicated that most species of sharks
will not attack hairy mammals such as swimming
laboratory rats. However, with the IFD enclos-
ing the baboon, the hair was not visually ap-
parent. It would appear that unfamiliar olfac-
tory stimulation or movements of the tranquilized
animal may have accounted for the unusual shark
behavior. Preliminary analysis of recent tests
of the IFD exposed to deep water (Pacific)

sharks in their natural habitat indicate prefer-
ential attack on anthropomorphic dummies
equipped with the more highly reflective and
conspicuous standard aircraft inflatable (yellow)
life preservers.

SUMMARY

1, A flotation device concept for infants and
small children incorporating life-support and
survival capabilities is described. In addition
to its application to aviation safety, the device
is of potential value for boating and other forms
of marine transportation.

2. The IFD provides in excess of 46 pounds
of buoyancy and, as recorded by surface and
underwater photography, demonstrates excellent
self-righting and stability.

3. Ventilation is accomplished by motion of
the device in water and/or flow of air across the
snorkel device. Either a 8-mph breeze or 6-inch
waves was suflicient to limit the CO, accumula-
tion to less than 0.759%. In still water the canopy
may be opened without compromising the occu-
pant’s safety.

4, Water has a specific heat approximately
1000 times that of air so that each cubic centi-
meter of water contacting the skin is capable of
taking up a thousand times more heat from the
body than a comparable volume of air for a
given change in temperature.’ Protection from
the effects of immersion in cold water is provided
by unicellular neoprene foam which limits the
heat loss of that portion of the body submerged.
The remainder of the body not subjected to im-
mersion may be enclosed in the canopy, reducing
heat, loss, and protecting the occupant from ex-
posure and immersion of the respiratory system
in rough seas.

5. Both the red and the black infant flotation
devices, containing anthropomorphic dummies or
baboons, were less attractive to sharks than an
anthropomorphic dummy wearing a standard
yellow inflatable life vest.



a

TECHNICAL REPORT STANDARD TITLE PAGE

To Report No. 2. Government Accession No 3. Recipient's Catalog No.
FAA~AM-71-37

& Title and Subtitle 3. Report Dare
EVALUATION OF AN IMPROVED FLOTATION DEVICE FOR July 1971

INFANTS AND SMALL CHILDREN

6. Performing Organization Code

7. Author! s)
Ernest B. McFadden
Joseph W. Young

B. Performing Organization Report No.

9%. Performing Organization Name and Address TO. Work Unit No.
FAA Civil Aeromedical Institute
P. 0. Box 25082 11. Contract or Grant No.

Oklahoma City, Oklahoma

13. Type of Report and Period Covered

12. Sponsoring Agency Nome and Address

Office of Aviation Medicine OAM Report
Federal Aviation Administration
800 Independence Avenue, S.W. 14. Sponsoring Agency Code

Washington, D.C. 20590

15. Supplementary Notes

This research work was performed under Task PRS-15.

16. Abstract

A simple, lightweight, life-support infant flotation device incorporating reliable
self-righting, thermal protection and automatic self-ventilation is described.
This design concept utilizes prior data relative to the centers of gravity of
infants and small children and exhibits excellent self righting. Thermal pro-
tection is incorporated through the use of insulative neoprene foam in con-
struction of the submerged portion of the device. Anesthetized adolescent
primates exhibiting body weights and metabolic requirements equivalent to that of
an infant or small child were used to test and confirm ventilatory capability as
induced by air or water motion.

An evaluation of the capability of the device to deter shark attack indicated
that the infant flotation device, when occupied by anthropomorphic dummies or
anesthetized primates, was less attractive to sharks than anthropomorphic
dummies wearing a standard yellow color inflatable life vest.

'

| 17 Key Words y WR SLYBET ES TS unlimited. Document may
Flotation Device, Aircraft Ditching, be released to the National Technical
Life Support, Survival Information Service, Springfield, Virginia
22151, for sale to the public.
-
19. Security Classif, (SPthis report) 20. Security Classif. (of this page) i No. of Pages | 22. Price

| Unclassified Unclassified 8 $3.00

e Form DOT F 1700.7 ce-69)



Federal Aviation Administration, Office of Aviation
Medicine, Civil Aeromedical Institute, Oklahoma City,
Oklahoma. EVALUATION OF AN IMPROVED
FLOTATION DEVICE FOR INFANTS AND SMALL
CHILDREN by Ernest B. McFadden and Joseph W.
Young. July 1971. 8 pp. Report No. FAA-AM-

A simple, lightweight, life-support infant flotation device in-
corporating reliable self-righting, thermal protection and
automatic self-ventilation is described. This design concept
utilizes prior data relative to the centers of gravity of infants
and small children and exhibits excellent self righting.
Thermal protection is incorporated through the use of insula-
tive neoprene foam in construction of the submerged portion
of the device. Anesthetized adolescent primates exhibiting
body weights and metabolic requirements equivalent to that
of an infant or small child were used to test and confirm
ventilatory capability as induced by air or water motion.
An evaluation of the capability of the device to deter shark
attack indicated that the infant flotation device, when occupied

by anthropomorphic dummies or anesthetized primates, was
less attractive to sharks than anthropomorphic dummies
wearing a standard yellow color inflatable life vest.

I. McFadden,
E. B.
II. Young, J. W.

Descriptors
Flotation Device
Aircraft Ditching
Life Support
Survival

Federal Aviation Administration, Office of Aviation
Medicine, Civil Aeromedical Institute, Oklahoma City,
Oklahoma. EVALUATION OF AN IMPROVED
FLOTATION DEVICE FOR INFANTS AND SMALL
CHILDREN by Ernest B. McFadden and Joseph W.
July 1971. 8 pp. Report No. FAA-AM-

A simple, lightweight, life-support infant flotation device in-
corporating reliable seli-righting, thermal protection and
automatic self-ventilation is described. This design concept
utilizes prior data relative to the centers of gravity of infants
and small children and exhibits excellent self righting.
Thermal protection is incorporated through the use of insula-
tive neoprene foam in construction of the submerged portion
of the device. Anesthetized adolescent primates exhibiting
body weights and metabolic requirements equivalent to that
of an infant or small child were used, to test and confirm
ventilatory capability as induced by air or water motion.
An evaluation of the capability of the device to deter shark
attack indicated that the infant flotation device, when occupied

by anthropomorphic dummies or anesthetized primates, was
less attractive to sharks than anthropomorphic dummies
wearing a standard yellow color inflatable life vest.

I, McFadden,
EB. B.
IL. Young, J. W.

Descriptors
Flotation Device
Aircraft Ditching
Life Support
Survival



capability of the device, it was found that after
3 hours in 6-inch waves, the carbon dioxide con-
centration did not exceed 0.75%. (Figure 5)
By creating an artificial condition in an indoor
pool and isolating the device from all water
motion and air currents, it was possible to pro-
duce an accumulation of 6.4% CO, in a period
of 30 minutes. Upon initiation of a very light
air movement (3 mph), the CO, dropped to
0.59% in less than 5 minutes,

3. Thermal protection: The thermal conductiv-
ity of neoprene foam approximates 4.5 kcal./
sq.m./hr./°C./per cm. thickness. Based upon
the immersed surface area of a 38-year-old child,
the heat loss attributable to Newtonian cooling
through the 14-inch neoprene foam may be
crudely estimated at 3 kcal. per °C. The total
basal heat production of a 2% to 3-year-old child
ranges from 25 to 80 kcal. However, there is
no information relative to the CLO value of
skin and subcutaneous tissue. In addition, that
portion of the body not immersed is subject to
heat loss due to convection, conduction, radiation,
and evaporation, These variables are not ac-
counted for in the above calculation. Under
certain conditions, the transparent canopy may
produce a heat gain due to the “greenhouse
effect,” Due to these variables, a precise and

al
°
T

3.07 after 3 Hrs
6" Waves

PER CENT COo
Db
[o}
T

accurate calculation of heat loss is not possible.
However, it is obvious that considerable increase
in body heat retention and survival time may be
realized with this device, The ID may be de-
flated and used as a thermal bassinet in a life
raft. Similarly, on land, the IFD provides
excellent anti-exposure capability.

4, Impact protection; Although not tested and
evaluated, it would appear that the IFD, by
nature of its construction, would provide protec-
tion from impact injury. Critical portions of
the body—face, heat, thorax—would receive some
degree of impact protection since the inflatable
compartments surrounding this area would func-
tion in a similar manner to air bag designs for
automotive and aviation crash injury minimiza-
tion.

5. Ability to deter shark attack: It has been
reported in the literature that color and reflectiv-
ity of immersed objects appear to have some
effect. upon encouraging or deterring attack by
predatory marine life. Evaluations of a baglike
device designed by Dr. Scott Johnson and known
as the Johnson Shark Screen indicate that
darker, non-reflective bags of large size and in-
definite shape which concealed the human form
appear to deter shark attack by sharks in captiv-
ity and in their natural habitat.‘

Initiate 3 mph
Wind Velocity
XY

hor
faci
diff
por
ven.
plet
cel
cup
prir
and
Lab
Spe
shai
(gu
hina
gerc
dur
only
curt
was
pict
SCL
TT
carr
cater
than
life
were
nigh
dum
react
baba
the ;
stud.
will
labor
ing
pare!
tory
anim
beha
of t.

|
Hl + —
30 MINUTES

Ficurk 5. Sample recording showing the effect of 6-inch waves, very calm water without air movement, and a
Ly 8-mph, air movement without wave action,

6



mensit
device
dren :
of the
ments

1&6
series
anthre
3-year:

Ficune 1. Initial prototype of the infant flotation device occupied by a child anthropomorphic dummy,



\ a

EVALUATION OF AN IMPROVED FLOTATION DEVICE EOR INFANTS
AND SMALL CHILDREN

A survey of accident histories of prior open
sea transport aircraft ditchings indicates that a
number of small children or infants involved in
such an accident did not survive. Due to the
relationship between the center of gravity and
stature, the present life jackets may not maintain
the body of a small child in an upright position.
Simple movements, such as holding the hands
above the head, will shift the center of gravity
to the extent that the child may rotate, submerg-
ing the face and head. In choppy water, the
child or adult life preserver provides little pro-
tection for either infant or small child from
inspiration of water. Efforts by adults to sup-
port a child under the adverse environmental
conditions encountered in open sea ditchings are
frequently ineffective.

Cold water immersion poses another difficult
and challenging problem. The specific heat of
water is approximately 1,000 times that of air,
a given volume of water being capable of taking
up to 1,000 times the heat of a comparable volume
of air Infants and small children have a body
surface area per unit of body mass 2-3 times
that of an adult.* Additionally, the total body
weight of infants and small children ranges
from Y% to % that of an adult with a com-
mensurate reduction in total stored or specific
heat. Survival times are, therefore, drastically
reduced due to the larger surface area per unit
of body mass and the reduced quantity of heat
initially available to maintain body core tempera-
ture. In order to test and evaluate a more pro-
tective flotation device based on known anthropo-
morphic and physiological ‘characteristics of
infants and small children, & series of experi-
ments was conducted as described below.

METHODS AND: RESULTS ;

A simple, lightweight, life-support infant flo-
tation device (IFD) was designed and tested
extensively. Primary design considerations in-

¢

cluded: (1) reliability of buoyancy, stability and
self-righting characteristics; (2) self-ventilation;
(8) thermal protection; (4) impact injury mini-
mization; and (5) ability to deter shark attack.

A prototype infant flotation device constructed
to meet these criteria has been previously de-
scribed.* Briefly, the flotation portion of the
IFD consists of two separate inflatable buoyant
compartments of equal diameter, one a complete
horizontal circular tube and the other a vertical
half-circle sewn to the perimeter of the hori-
zontal segment. Inflation is accomplished by a
16-gm. carbon dioxide cylinder attached to each
of the inflatable compartments. A means for
orally inflating each compartment is also pro-
vided. The half-circle compartment is designed
to assume a vertical position at right angles to
the full-circle flotation compartment in order
to support a protective canopy or enclosure.
(Figure 1) This transparent canopy enclosure
is secured by means of a zipper and velcro clo-
sure. The lower portion of the IFD consists of
a tapered bag fabricated of %4-inch unicellular
thermal insulative neoprene rubber foam. This
design provides a minimum surface area and
avoids the familiar problem of “insulation of
small cylinders.” The upper portion of the neo-
prene bag nears its attachment to the horizontal
flotation ring is flared quite radically so as to
provide a diaphragm action when the device is
floating in water and cause a “pumping” or
breathing action through the snorkel, ventilating
the device in choppy water. In calm water the
front canopy may be left open. A padded seat
with shoulder straps limits vertical displacement
of:the child if dropped into the sea in an in-
verted attitude. A lanyard permanently attached
to the IFD and terminating in a swivel snap is
provided for direct connection to the “D” ring
of the adult’s life vest. Total weight of the IFD
is approximately 414 pounds. With certain
modification, including the enlargement of di-



is Dat btn at ah

ACKNOWLEDGMENTS

The authors wish to acknowledge the assistance provided by F. F. Win-
ters, D. E. Rowlan, and J. M. Simpson. In addition, special acknowledgment
is due Dr. Perry W. Gilbert, Fred Martini, Blair Irvine, and Hugh Scott of
the Mote Marine Laboratory for the scientific counsel and assistance in con-
ducting the shark deterrent studies.

A
sea
num
such
relat,
statu
the k
Sim;
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to th
ing |
child
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port
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and
water
a giv
up to
of air
surfac
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weigh
from
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heat.
reduce
of bo
initial
ture.
tective
morpl
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ments

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tation
extens.