Skin: No extensive contact dermatitis history
and no person with an infectious dermatitis tend-
ency would be cleared. If dandruff therapy for
a given individual may be forecast, he must show
prior therapeutic success with given techniques.
Seborrheic dermatitis is the underlying basis
for dandruff and the need for appropriate care
of seborrheic dermatitis was one of the findings
in the Apollo lunar flights. In prolonged space
missions there is the possibility of a complicating
infectious dermatitis and potential incapacitation
if this condition is severe.

Gastro-intestinal: No colitis, unhealed peptic
ulcers or irritable GI tract difficulties would be
cleared. Dental-oral organs must be appropri-
ately treated for space flight conditions prior to
departure.

Senses: All of the sensory functions should be
within the ranges considered normal for the age
of the individuals. If there is a history of con-
junctivitis, successful prior therapy must be estab-
lished. It was found in the Apollo missions that
conjunctivitis became an unanticipated annoy-
ance. This conjunctivitis may have resulted
from a number of factors which are associated
with confinement for prolonged periods in sealed
weightless environments. These could involve
conjunctival contact with tiny particulate matter
which remains suspended in the weightless state.
Persons prone to conjunctivitis can experience a
follow-on blepharitis and visual difficulties ulti-
mately leading to incapacitation. Attention to
these tendencies must be given prior to departure.
The vestibular organ should be tested prior to
departure during the medical qualification period
for hyper-sensitivity to angular accelerations.

Age: Although advanced age would, of course,
be a restraining factor, certain attributes of ma-
turity have been identified as desirable for space
missions, assuming that appropriate compensa-
tions are effected.*  Weightlessness effects on
growth of children and adolescents are not yet
adequately assessed.

From the pre-flight standpoint, non-crew mem-
bers will require careful medical evaluation, and,
following clearance by certain criteria, should be
fully briefed with respect to the forthcoming trip.
This briefing should include the use of motion
pictures, sound effects, and simulator experience.
Each passenger should be provided with a per-
sonal means of exercising and light sedatives

should be tried for idiosyncrasies prior to the
trip. Some advance planning concerning recrea-
tion should be discussed as should arrangements
concening personal finances prior to departure.
In general, each accepted occupant would ulti-
mately be termed “physically and psychiatrically
oriented for space flight.” Tach accepted occu-
pant will receive instruction in the space context
concerning personal hygiene, dental hygiene, toilet
factors (urine, feces, menstruation) and morale.
For the medical aspects with respect to passen-
gers (which may also include individuals drawn
internationally), the pre-determined guidelines
would involve individual assessment by an aero-
space surgeon.

From the medical standpoint, it is noteworthy
that all of the manned space flight activities
as of the present time have demonstrated that
weightlessness has not presented the manifold
medical difficulties previously predicted by early
theoreticians.” The possibility of rotating the
space facility to create an artifiical gravity is
considered.’ However, coriolis forces could stim-
ulate vestibular vertigo under these circum-
stances, especially during rapid head movements
contrary to the rotation. Perhaps a subunit of
the station can be spun at a relatively rapid rota-
tional velocity, with each occupant spending a
small percentage of each day standing in the
unit with a relatively rigid posture. This will
foster maintenance of gravitational physical con-
ditioning.

Ill. Life Support and Protection Standards.

The aerospace transportation booster and shut-
tle will primarily serve as vehicles for trans-
porting crew, passengers, and cargo to the orbital
facility. The orbital facility will constitute the
habitat for the occupants and in the second gen-
eration version may remain as stated for periods
up to, and in excess of, one year in earth orbit.
Accordingly, in addition to the occupant stand-
ards and aeromedical briefing factors, certain en-
vironmental and design features require delinea-
tion for the guidance of design engineers and
operating personnel.

The above standards include radiation stand-
ards for those sources of radiation which can be
controlled (or avoided), For terrestrial individ-
ual radiation workers, the standards have been
placed at 5 rems/year and for terrestrial individ-



nologically feasible of highly inert, fire-resistant
materials. Off-the-shelf items obtained pri-
marily on the basis of low unit cost and ready
availablility should be proscribed in all but the
most carefully assessed circumstances. Poly-
imide, polyamide, and other advanced materials,
must be considered for utilization in these ve-
hicles.

Eight-hour duty shifts in the orbital facility
are envisioned, with artificial daylight possible

on each shift. It is feasible that circadian
rhythms can be phased appropriately for each
shift, precluding dysfunctions and performance
impairments.

Incorporation of the available aerospace med-
jcal data in the design, operation and occupant
selection programs for the general-use aerospace
transportation vehicles will help assure certifica-
tion by the responsible regulatory authority and
safety of repetitive missions.

REFERENCES

1, United States of America, Air Commerce Regula-
tions, Government Printing Office, Washington, D.C.,
1926.

2. Federal Aviation Administration, Tentative Airworth-
iness Standards for Supersonic Transports, Wash-
ington, D.C., January 1, 1971.

3. Mohler, S. R., “Aeromedical Research: The New
Generation Aircraft,” Third Annual Report to In-
dustry on FAA R & D Activities, Washington, D.C.,
June 10, 1969.

4, Gerathewohl, 8. J.; Siegel, P. V.; and Mohler, S. R.

Medical and Psychological Aspects of Mass Air

Transportation, Ninth Annual Meeting, German Aero-

space Medical Association, Munich, Germany, No-

vember 11-12, 1970. FAA Report AM 71-10.

Langham, Wright (Chairman), Radiation Protec-

tion Guides and Constraints for Space-Mission and

Vehicle-Design Studies Involving Nuclear Systems,

Report of the Radiobiological Advisory Panel of th

Committee on Space Medicine, National Academy

of Sciencies, Washington, D.C. 1970.

a

agsi4

6. Summerfelt, W. A. The Space Shuttle: A Develop-
ment Challenge, National Aeronautics and Space Ad-
ministration, Washington, D.C., October 29, 1970.

7. Gerathewohl, 8. J., and Steinkamp, G. R., “Human-
Factors Requirements for Putting a Man in Orbit,”
Astronautica ACTA, Vol. V., Fase. 1, 1959.

8. Gerathewohl, S. J., “Development of Manned Arti-
ficial Satellites and Space Stations,” Advances in
Space Science and Technology, Vol. 4, Academic
Press, New York, 1962.

9. Berry, C. A., “Medical Experience in Manned Space
Flight,” Aerospace Medicine, Second Edition (H. W.
Randel, Ed.), Ch. 29, Williams and Wilkins, Balti-
more, 1971.

10. Pecoraro, J. N., “Shuttle Life Support, Protective
Systems, and Crew System Interface Technology,”
Astronautics and Aeronautics, Vol. 9, No. 2, Feb-
ruary 1971.

11. Mohler, S. R., “Aging and Space Travel,” Aero-
space Medicine, Vol. 33, May 1962.


Tante I—Orbital Facility: Hypothetical Crew/Other
Occupant Make-Up*

Commander-Astronaut_
Astronauts_
System Specialists.
Atomic Specialists_.
General Operating Technicians.
Surgeon-Pathologist.- -
Space Medical Officer
Space Nurse-Technician.
Dietician/ Assistant Dietician -
Physical Plant-Sanitation- .--

RUN EE RWRAH

Total__

Scientists.
‘Technicians.
Secretary-Administrative.

scientists,

short-term

Observers,
historians, other**

newsmen,

*Any of these may be male or female
**For cooperative International efforts, includes in-
terpretors

prior analyses.® These selected topics are pre-
sented here primarily as general take-off points
with respect to later, more specific and detailed,
medical parameters. These are for the purpose
of initiating medical thinking within these
broader areas with respect to passengers in aero-
space transportation vehicles.

Sew: Representatives of both sexes are accept-
able.

Skeletal System: Persons with osteoporosis
could encounter difficulties in re-adapting to a
one g environment following prolonged orbital
flight; osteoporosis would be, therefore, disqual-
ifying. One reason for highlighting osteoporosis
is that earth orbital and lunar missions have
demonstrated that a measurable degree of bone
decalcification accompanies exposure for pro-
longed periods at zero g environment. Osteo-
porotics would be expected to experience addi-
tional bone loss which they could possibly ill-
afford. Certain exceptions following earth-based
studies may be made.

Endocrine System: Initially, no diabetics re-
quiring insulin should be considered due to the

lack of support facilities in the early stages of
orbital vehicular flight. Ultimately, controlled
diabetics may be cleared.

Neuro-psychiatric Aspects: Epileptics, alco-
holies, addicts, psychotics, and persons with per-
sonality disorders would not be cleared. The
term “personality disorder” would be used in this
context to indicate individuals who were incapable
of serving as members of the relatively small-
sized confined orbital group.

Problems in relationship to theft, uncontrol-
lable hostility, overt uncontrollable aggressive
acts and other extreme characteristics are in-
cluded. It may be that certain unusual per-
sonality characteristics would be desirable for
occupants. These would include tolerance to long
periods of monotony and isolation and abnor-
mally controlled emotional qualities. Also, un-
usually strong feeings of security in an enclosed
and isolated environment may be an asset.

Cardiovascular System; All occupants should
receive clearance on the basis of a stress-cardio-
vascular test program. Ultimately, coronary
occlusion may be cleared if recovery is adequate.
No untreated or advanced anemics or leucopenics
could be cleared until the conditions are rectified.
Hypertensives in excess of 170/96 or hypotensives
below 90/60 millimeters mercury would initially
be screened. No uncontrollable cardiovascular
dysrhythmias would be cleared.

Renal: No advanced glomerulonephritis would
be cleared and stone-formers would be screened
out. In the development of bone demineraliza-
tion under weightlessness conditions a certain
amount of calcium is excreted in the urine above
that normally discharged. Accordingly, if an
individual has such conditions as pyelonephritis,
ureteral strictures, and an enlarged prostrate
gland, or other renal condition which may lead
to stasis of urine, corrective therapy should be
accomplished prior to clearance for a mission.
Calcium or uric acid stones may form under the
above circumstances and also inflammatory con-
ditions can develop.

Pulmonary : No significant emphysema, no lung
blebs, and no significant bronchiectasis would be
allowed. If lung blebs are present, some con-
sideration could be given to providing clearance
for a mission by previous ground studies utilizing
an altitude chamber as is done now with aircrew
members.


ual general population members, 500 millirems/
year. Second generation space facilities should
be designed for limits consistent with the radia-
tion worker upper limit until more information
is available suggesting otherwise. This applies
to self-contained nuclear auxiliary power unit
shielding plans and consideration of other sources
of radiation. Recently tendered radiation stand-
ards for space-mission and vehicle-design studies
involving nuclear systems, are considered exces-
sively high for passengers of general-use aero-
space transportation vehicles.’ Some of the occu-
pants may have received pre-mission medical
radiation exposures, limiting their orbital stay.

Environmentally, an interior atmosphere of
80% nitrogen, 20% oxygen, at a sea-level pres-
sure, is an optimal design criterion, The
U.S.S.R. Vostok and Voskhod spacecraft were
provided with such an atmosphere.? A separate
smoking-room with scrubbed air for those who
cannot break the tobacco habit is recommended,
containing a bar facility, judiciously stocked with
low-congener, quality, beverage for morale pur-
poses with respect to that segment of the occu-
pants who may have need of such a facility. The
low-congener alcohol beverages will not only
minimize hangover effects and subsequent per-
formance derogation, but also will minimize the
space-cabin air-borne contaminant problems.

The atmosphere within the overall facility
will require certain active controls, which, in ad-
dition to removing dust, odors, and the metabol-
ically produced carbon dioxide, will monitor,
through the use of miniaturized sensor systems,
and remove, specific trace substances. These trace
substances, irritating and potentially noxious,
may consist of acetylene, carbon monoxide, sul-
phur dioxide, and various aliphatic and aromatic
hydrocarbons plus certain other inorganic sub-
stances. (See Table Two.) The miniaturized
sensor system may utilize a mass spectrometer
and/or a type of gas-chromatograph. As can be
seen, the “out-gassing” product classes yielded
by materials and man relate to the categories of
alkanes, alkenes, alcohols, ketones, aldehydes,
alkyl and aryl halides, aliphatic nitrogens, and
carboxylic acids. In addition, benzene, silicones
and inorganic substances are involved. Lubricants
ean yieuld chlorine substituted fluoro-carbons,
polyurethane yields CO., resins may yield ammo-
nia, and coatings may out-gas plasticizers and sol-
vents. The Threshold Limit Values for air-borne

Tass II.—Illustrative Trace Contaminants which are of
Significance to Orbital Facility Atmospheres

Derived from Man
Acetaldhyde_

TLV* less than:

-1,000 ppm
_-50 ppm

Ammonia.

Carbon Monoxide.
Ethyl Aleohol - -
Hydrogen. ---
Hydrogen Sulfide
Mercaptans....

Methane dangerous

Methyl Alcohol. -200 ppm
Methyl Ethyl Ketone. -200 ppm
Derived from Materials TLY* less than:
Benzene. _-25 ppm
Butane and Derivatives. dangerous

Butyl Alcohol and Derivatives,
Carbon Disulfide
Chloroform.
Cyclohexane --

Dichloroethane and Derivatives
Dichloromethane.._.....--.---

Ethylene...
Formaldehyde... ---
Fluorotrichloromethane.
Methyl Iso-butyl Ketone.

1,000 ppm
-100 ppm
dangerous

*The Threshold Limit Values presently available
(1970) are based upon an 8-hour day, 40-hour week,
occupational exposure. TLV’s for 24 hour spacecraft
internal atmosphere exposure may necessarily be con-
siderably lower (see text). TLV’s are parts of vapor per
million parts of contaminated air by volume at 25°C
and 760mm Hg pressure.

**Eight-hour day, 40-hour week occupational exposure
is 50 ppm.

contaminants prepared by the American Con-
ference of Government Industrial Hygienists
(1970, 1014 Broadway, Cincinnati, Ohio) may
be used as a rough guide with respect to space-
craft atmospheres, but it must be stressed that
these values are developed for 8-hour work day,
40-hour work week exposures. Necessarily, space
station oceupants will be exposed 24 hours per
day for long periods, requiring lower Threshold
Limit Values in many cases.


TECHNICAL REPORT STANDARD TITLE PAGE

1. Report No. 2. Government Accession No. 3. Recipient's Catalog No. “|
FAA-AM-~71-33
4, Title and Subtitle 5. Report Date
CIVIL AEROMEDICAL STANDARDS FOR GENERAL-USE July 1971
AEROSPACE TRANSPORTATION VEHICLES 6. Performing Organization Code
The Space-Shuttle Follow-on
7. Author!s) 8. Performing Organization Report No.

Stanley R. Mohler, M.D., and
Siegfried J. Gerathewohl, Ph.D.

9. Pertorming Organization Name and Address 10. Work Unit No.
Office’ of Aviation Medicine
Federal Aviation Administration

Department of Transportation THe Contract or Grant No.
800 Independence Avenue, S.W,

Washington, D.C. 20590 13. Type of Report and Period Covered
12. Sponsoring Agency Nome and Address

Office of Aviation Medicine OAM Report

Federal Aviation Administration
Ropartment of Transportation

800 Independence Avenue, S.W. 14. Sponsoring Agency Code
Washington, D.C. 20590

15. Supplementary Notes

16. Abstract

Second-generation general-use aerospace transportation vehicles will evolve,

and aerospace medical specialists must provide timely medical criteria for

(a) occupant selection, (b) vehicle design features, and (c) operational
guidelines. Incorporation of this aeromedical data will result in (a) enhanced
mission success and mission efficiency, and (b) minimized opportunity for
mission failure, accidents, and long-range adverse consequences due to human
factors deficiencies. The data include medical standards for the occupants plus
standards for oxygen, nitrogen, carbon dioxide and monoxide, humidity, heat,
water vapor, internal noise, radiation, and other items.

17. Key Words 18. Distribution Statement
Space Shuttle, Orbital Flight, Availability is unlimited. Document may
Advanced Aerospace Systems, Manned be released to the National Technical
Orbital Laboratory, Aerospace Medical Service, Springfield, Virginia 22151, for
Standards sale to the public.

19. Security Classif. (of this report) 20. Security Classif. (of this page) ZI. No. of Pages | 22. Price
Unclassified Unclassified 6 $3.00

Form DOT F 1700.7 (8-69)



Carbon dioxide levels should be maintained
below 3.8 mm Hg partial pressure which at sea
level is 0.5% of the atmosphere, and carbon
monoxide must be maintained at levels below
0.001% (10 parts per million by volume). Stra-
tegically located occupant-accessible emergency
oxygen supplies and masks should be available
to all occupants in the event of accidental in-
creases in the atmosphere within any of the aero-
space transportation vehicles of high levels of
toxic substances or, conversely, the development
of low levels of oxygen. Portable walk-around
oxygen equipment should be available for safety
purposes. The supply of oxygen should be com-
mensurate with the calculated duration of pres-
surization emergency circumstances. In addition,
“explosive” failures of various compartments
within the pressure vessels of the vehicles may
occur, and techniques for personnel transfer from
one compartment to another must be a design
feature. These circumstances would involve se-
lective airlock facilities, light-weight body
protective material (silvered polyimide), and
emergency food and water rations in each com-
partment. These approaches would serve in the
event of structural damage by meteorites. or
intrinsic pressure vessel tears, and would help
retain occupant viability until repairs or shuttle
departure are effected.

A separate, independently ventilated, compart-
ment for the isolation of ill persons is necessary,
especially with respect to those with infectious
disease. For the bodies of those who may die,
a suitable morgue facility with appropriate pre-
servatives is necessary. Later detailed study of
all of the tissues of any deceased will be extremely
important in revealing the long-term effects of
space-flight on man and of critical significance
to the well-being of space travelers.

Tn order that the liquid and solid excremental
wastes are processed in an effective manner, or-
ganic bactericides, together with inorganic viri-
cides and fungicides, supplemented by heat, and
other methods are planned.*? In addition, in-
organic agents which include the halogens and
certain heavy metals, may be utilized. Jet trans-
port aircraft and shuttle vehicles are suitable for
incorporation of urine recyeling systems with
respect to toilet flushing.

The orbital space vehicle may incorporate
special liquid sources for toilet processing. Water
reclamation processing may be accompliished with

respect to liquid human excrement, ultimately re-
sulting in a potable water distillate. Means of
assuring potability of this water through molec-
ular monitoring and microbial checks may be
necessary. All urine hormones, enzymes, kinins,
urochromes, mucins, casts, bacteria, cells, proteins
and other substances, including aromatics, must
be removed. Occupants during booster opera-
tions may not have, during certain portions of
flight, the freedom to proceed to and from toilet
areas. Pre-flight partial dehydration and low
residue intake may become an operational feature
prior to booster departure. This will accommo-
date any periods of “holding” during the pre-
blast-off phase.

Since accelerations and decelerations are not
anticipated to exceed 3 g’s during ascent and re-
entry, this aspect is of relatively little medical
significance. Noise and vibration levels in the
orbital facility should be damped to the extent
possible, especially in sleeping quarters where
these levels should not exceed 40 dB. Optional
music/at various stations would appear desirable.
Adjustable interior temperature and humidity
levels of 20-22°C and 50-60% are design objec-
tives." Since in the weightless environment there
is no natural heat convection, forced air drafts
are necessary, adjustable but not, in general ex-
ceeding comfortable flow velocities. Ten cubic
feet per minute per individual may serve as a
minimal circulation guide, adjustable downward,
or upward by a factor of two, with local flow
controls adjustable upward by a factor of four.

Interior colors should be selected on the basis
of available psychological knowledge. The colors
selected for the recreation and work areas should
be compatible with area use. Interior pastoral
and other scenes for decor and satisfaction may
be tried and opportunities to exercise distant vi-
sion should be frequent to avoid acquired myopia.
Private areas should be arranged for each occu-
pant, free from any distractions during periods
of individual study and contemplation. All
areas should have controllable “white” illumina-
tion.

It is of significance to plan for a quality in-
terior in all three vehicles of the second- genera-
tion general-use aerospace transportation system.
Electrical wiring, switches, conduits, hydraulic
systems, servomotors, panels, interior walls, furni-
ture, foodware and other items must all be of the
highest quality and constructed insofar as tech-





CIVIL AEROMEDICAL STANDARDS FOR GENERAL-USE AEROSPACE
TRANSPORTATION VEHICLES

The Space-Shuttle Follow-on

I. Introduction.

A follow-on to the planned first-generation
space shuttle and orbital facility system will pro-
vide a means of placing distinguished scientists
and other persons in earth orbital facilities for
periods lasting potentially for many months. Se-
lection criteria with respect to astronaut clearance
for space flight will be, in many cases, a barrier
with respect to clearance for space flight of non-
astronaut personnel. Accordingly, carefully de-
veloped standards for non-astronaut personnel
must be defined to assure that all of those having
legitimate reason for space flight are able to par-
ticipate, consistent with individual biological and
physical conditions.

The second-generation aerospace transportation
vehicle system is projected to involve: 1) a
manned reusable booster: 2) a shuttle spacecraft
which is capable of returing from orbit for an
aero-dynamic non-parachute earth landing; and
3) a manned earth-orbital facility.

These second-generation vehicles will very
likely become operational well before the end of
this century. Considerable planning in this effort
is now underway by engineering personnel. It is
the purpose of this paper to delineate some of
the medical parameters which can be established
as tentative guidelines for use by engineers and
operational personnel with respect to the safe
carriage of that segment of the public having
valid reasons for transport in these vehicles (over
and above crew members).

Civil air transportation vehicles have been
certified as airworthy for safe passenger trans-
port by the United States since 1926.1 The evolu-
tion of these vehicles has successively presented
the licensing authorities with increasingly chang-
ing environments necessitating revised airworthi-
ness standards and operational practices.* The
latest example in civil aviation is the supersonic

transport which operates at the fringe of space
and for which tentative airworthiness standards
have been issued by the U.S.2* The general-use
aerospace transportation vehicles utilized for. the
carriage of non-astronaut members of the public
will similarly be subjected to man-rated criteria
and will be licensed by the responsible Federal
authority in accordance with aerospaceworthiness
standards. In addition, occupant physial stand-
ards must be defined which enable appropriate
pre-flight screening.

The three major components of the general-use
aerospace transportation system are as follows.*
The booster prototype is projected to have a
length of approximately 80 meters, an operational
empty weight of 200,000 kilograms, a landing
speed of approximately 150 knots, and a crew of
two astronauts. Airbreathing jet engines may
be used to assist in landing. The shuttle vehicle
is projected to be approximately 60 meters in
length and, in the empty configuration, to weigh
approximately 88,000 kilograms. Its landing
speed upon return to earth is projected to be ap-
proximately 160 knots. For the shuttle vehicle,
a crew of four astronauts and a passenger load of
about 20-22 individuals is hypothesized. For
the orbital facility, within which personnel may
remain for periods of three months to one year,
a crew of approximately 30 and a non-crew com-
plement of 35-40 are projected. Personnel de-
parting as non-crew members for accommodation
in the orbital facility may include astronomers,
chemists, biologists, geographers, meteorologists,
family members (later development) and others.
(See Table One.)

II. Aerospace Medical Standards.

The following tentative aerospace medical pa-
rameters (not. meant to be fully encompassing)
are seen as necessary and are based in part on