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NASA Technical Memorandurfi 58255

NASA-TM-58255 19840012972

Space Station

Medical Sciences Concepts

February 1984

.L#,NGLEYRESEARCHtEN rER

LIBRARY,NASA

t:iI',J.':_I'ON , VIRGINIA , ,.

NationalAeronauticsand

SpaceAdministration

NASA Technical Memorandum 58255

Space Station

Medical Sciences Concepts

Edited by

John A. Mason and Philip C.Johnson, Jr., M.D.

Lyndon B. Johnson Space Center

Houston, Texas
This document shouldbe useful to anyone interestedin planningthe life

sciences aspectsof the NASA Space Station. It supplementsNASA Technical

Memorandum58248 "MedicalOperationsand Life SciencesActivitieson Space

Station" (October1982). Some of the commentsherein apply to a smaller Space

Station,others applyto a more mature station.

This documentwas written by the Medical SciencesSpace StationWorking Group.

Chairman JohnA. Mason

Members MichaelW. Bungo Philip C. Johnson

John B. Charles James S. Logan

MartinE. Coleman Bernard J. Mieszkuc

Gary R. Coulter MichaelA. Reynolds

MaynardC. Dalton RichardL. Sauer

JosephC. Degioanni CharlotteG. Smith

William J. Frome MalcolmC. Smith

LeonardGardner NicholasTimacheff

HerbertR. Greider JamesM. Waligora

John W. Harris

Jerry L. Homick preparedthe chapter on acousticsand D. Stuart Nachtwey prepared the chapter on radiation. Both Drs. Homick and Nachtweyare with the

Space and Life SciencesDirectorateat JSC. JeannieCollisonof Technology

Incorporatedcontributedto the developmentof severalof the conceptspresented. Carole Boney assistedin the organizationof the document. The Working Group wishes to give thanks and recognitionto these individualsfor their

contributionsto the preparationof this document. Special recognitionis

given to ProfessorLarry Bell, Director,EnvironmentalCenter, Universityof

Houston, and his associatesMelanie Tang, Li Hua, and Spencer Ng who provided

the illustrativesketchesunder contractNAS9-16593. Their patience and

understandingduringthe developmentof the conceptualsketches is much

appreciated.
CONTENTS

Page

ABSTRACT ................................ i

INTRODUCTION.............................. i

EXECUTIVESUMMARY............................ 2

OPERATIONS

MEDICALANDBIOLOGICALRESEARCH................... 6

EXTRAVEHICULARACTIVITIES ...................... I0

NEEDFORBIOBEHAVIORALSERVICES ................... 15

HEALTH MAINTENANCE

MEDICAL CARE ............................. 18

MAINTENANCEOF DENTAL HEALTH ..................... 22

MAINTAININGHEALTH THROUGH PHYSICAL

CONDITIONINGAND COUNTERMEASURES.................. 26

HABITABILITY

PROTECTIONFROM RADIATION ...................... 30

ATMOSPHERICCONTAMINATIONCONTROL .................. 34

ATMOSPHERICCOMPOSITION ....................... 38

NOISE POLLUTION ........................... 42

FOOD SUPPLY AND SERVICE ....................... 46

CLOTHINGAND FURNISHINGS....................... 50

EDUCATIONALIMPLICATIONS ........................ 54

CONCLUDINGREMARKS ........................... 57

APPENDIXES

A. WORKING GROUP MEMBERSHIP.................... 59

B. SOVIET SPACE STATIONS ..................... 63

C. PHYSIOLOGICALLYACCEPTABLESPACE

STATIONAND PRESSURESUIT PRESSURES ............. 69

D. SUPPORTINGHEALTHMAINTENANCEDATA .............. 75

iii

ABSTRACT

This publication presents current life sciences concepts relating to Space

Station including the following: research, extravehicular activity, biobehavioral considerations, medical care, maintenance of dental health, maintaining

health through physical conditioning and countermeasures, protection from

radiation, atmospheric contamination control, atmospheric composition, noise

pollution, food supply and service, clothing and furnishings, and educational

program possibilities. Information on the current status of Soviet Space Stations is contained in appendix B.

INTRODUCTION

Purpose and Background

This document will provide NASAplanners and others with information concerning the life sciences aspects of the Space Station. It highlights the areas

in which the Johnson Space Center (JSC) can contribute expertise in the development of the Space Station.

In October 1982, the Medical Sciences Space Station Working Group (MS3WG)published NASATechnical Memorandum58248, "Medical Operations and Life Sciences

Activities on Space Station." Medical and life sciences requirements are presented as they were understood in the fall of 1982. Now, after the continued

development of 13 focus areas, new and more specific medical and li:fe sciences

aspects of Space Station operations are addressed.

Approach

Members of the MS3WGsupport life sciences for the Space Transportation System

(STS) or have specialized knowledge of a certain area (see appendix A). These

individuals have organized their focus areas in the following format:

o One page for conceptual sketch

o Two pages of narrative divided into the following sections:

- Introduction/Background

- Discussion

- Recommendations

o One page for table(s) and/or figure(s)

o Appendix (optional)

For the most part, the focus areas represent the concensus of the MS3WG.

Divergent viewpoints are presented to stimulate discussion and facilitate

decision making. The proposed Space Station atmospheric composition and pressure is emphasized.

The MS3WGdetermined that the development of concept sketches with a description has helped force the crystalization of concepts faster than otherwise

might occur. This helps prepare documentation development for Research and

Technology Objectives and Plans (RTOP's).
This Technical Memorandumis divided into four general categories: Operations, Health Maintenance, Habitability, and Educational Implications. Under

these categories, 13 concepts are discussed.

This document is written to supplement TM 58248. In addition, it should complement the recent NASAHeadquarters Life Sciences Planning Document "Space

Station Payload and System Definition." The MS3WGanticipates a sequel to

TechnicalMemorandum 58255 which will present other ]ife sciences Space Station focus areas which are maturing at the present time. The TechnicalMemorandum is expectedto be publishedin the fall of 1984.

EXECUTIVESUMMARY

As NASA moves from two decades of explorationand flight test activitiesinto

the Space Station era of industrializationand construction,the characterof

the missionswill change from short-occasionalto long-frequent,and the character of the crews will change from the pilot-astronautsto scientist-technicians. With the changed emphasis, NASA can no longer rely upon a small population of physicallyfit astronautsto do its work. The crew physicalcondition will vary because an individual'svocational skills will dictate the

choice rather than physical prowess. The change in mission objectiveswill

solve some of the problems of today but create new problems tomorrow. This

document,Space Station Medical SciencesConcepts,attemptsto address some of

the medicallyrelatedfactors which must be consideredif NASA is to make this

shift in mission emphasis. The problems suggestedmust be solved or at least

addressedbeforeplanningfor Space Station is complete.

Medical researchactivitiesmust play an importantrole in early Space Station

activities. Through researchthe industrializationof the later Space Station

years will be made practical. Researchwill be neededto make the environment

safe for this new work. Early medical researchmust addressthe "potentially

serious" physiological problems of the crewmembers exposed repeatedly to

microgravityfor long durations. As the program evolves and preventativesand

therapiesare found, any person can safely participatein these missions. By

that time, biological researchwill supercedemedical researchas biologists

take advantageof microgravityto determinehow gravity influencedthe evolutionary developmentof plantsand animals.

Gradually,biologicalresearchwill use laboratoryspace previouslyneeded in

medical research. Preparingfor biologicalresearchwill requireanimal quarters and laboratories separated from the crew's living areas. This will

requireseparateatmospheresand barriersnot needed for medical research.

Extravehicularactivities (EVA) are a major use for a Space Station. Only

through these activities can repair and construction be performed. EVA

requiresspacesuitswhich must be repairedregularlyand kept clean to prevent

odors and disease. The high cost of spacesuitsrequires that the suit must

fit several individualsand the durabilitymust allow multipletrips. It must

be easy to repair. The atmosphericpressuredifferencebetween the suit and

the airlock must not be so great that a prolongedprebreatheis needed before

a worker can leave for outside work. One solution would be to increasethe

suit pressure. This works well only if a glove can be developedwhich allows

dexterousmovementsat the chosen suit pressure. Present glove designs do not
work well if the pressure difference is greater than 5 pounds. If higher suit

pressures are needed, it will be necessary to develop a mechanical hand to

prevent the glove from being the limiting feature of the suit and of human EVA

activities.

As the crew mix changes from the more straightforward military-like astronaut

society of the present era, it will be necessary for biobehavioral scientists

to help NASAdevelop a space station society with rules of conduct and a command structure to maximize crew productivity and minimize psychological problems inherent in living in remote, dangerous environments isolated from

friends and family.

Inflight medical care is an absolute requirement of Space Station planning.

In all probability, an illness requiring a rescue mission will result in death

of the crewmember prior to the rescue. A rescue could take up to 21 days plus

the time needed to return the individualto Earth. Health care will embody

the triad of prevention,diagnosis,and treatment. Each will use biomedical

equipment designed for the station, along with medical procedures proven in

microgravity,and medical knowledgederived from terrestrialmedicine. Any

plan for a health maintenancefacilitymust be flexible. The facilitymust be

modular to allow quick change as mission emphasis changes and as new developments allow the use of more utilitarianequipment for diagnosis and treatment. The minimal requirementsof the facility must include the following:

routine laboratorycapability;imaging capability;life supportequipment;and

a hyperbaric treatment facility capable of reaching pressures at least two

times those in the Station.

Dental problems that cause disability or decreased work performance will occur

at the rate of 1%for each 90-man days in orbit. Dental care in Space Station

will build on the equipment and procedures used in Skylab. These included

dental training for the crewmembers, preflight clinical experience, onboard

equipment, and adequate supplies. For dental treatment in Space Station, a

dedicated area will be needed with adequate restraint systems, lighting, and

equipment for surgery, repair, and prophylaxis. Imaging capability will be

needed. Techniques useful for wound closure as well as all other aspects of

dental practice must be dev.eloped for disease prevention, treatment, and

trauma repair.

Exposure to microgravity produces negative calcium and nitrogen balances from

bone and muscle atrophy. This is accompanied by cardiovascular changes which

temporarily cause the heart to be less efficient at the time the crewmember

first returns to Earth. Exercise, whether voluntary or programmed by mission

rules, has been the traditional method used to counteract these negative balances. With the long duration missions and repeated exposures of Space Station workers, new approaches will be necessary and will require early planning

so that the physical conditioning will not be a burden to the individual. To

the present, no ideal solution is available to accomplish this necessary task,

and one could predict that intensive research will be necessary before NASA

can learn how to protect Space Station workers from bone-muscle atrophy.

Crewmembers in the Station will be exposed to continuous high ambient radiation levels which could become lethal if a solar storm were to hit the station. It can be estimated that the exposure will approximate 15 rads/tour.
This exceeds current occupational limits for radiation workers in the United

States. In theory, this could result in a higher incidence of neoplasms.

Calculations suggest that this could shorten life by an average of 150 days.

However, if the station is free of chemical contaminants and if the medical

care is above that of the population in general, the actual level of increase

and life shortening could be considerably below the predicted. This is somewhat similar to present-day NASAwhere the incidence of degenerative diseases

in the astronaut corps is lower than in the population generally because only

fit individuals are used and the medical care is near ideal. Plans should be

made for increased shielding in the event of a solar storm. The presently

planned rescue time would not give the crew the option of returning to a safe

haven unless an Orbiter were continuously on Station. Radiation exposure considerations would relate to the orbital inclination and heighth. A flat orbit

would sharply limit the Station's usefulness for Earth observations. A high

orbital altitude while ideal for the Station mechanics would greatly increase

the ambient radition exposure. A geosyncnronoun's orbit is precluded if man

is to be on board the Station because of the high radiation flux.

Atmospheric contamination control will be important since Space Station lacks

the near infinite dilution of ambient air available without planning here on

Earth. Methods to detect and remove contaminates must take high priority so

that problems can be solved before launch. As the industrial activities

increase, the number of toxic substances will increase. It will not be practical to perform human toxicity tests of every chemical used or potentially

produced. At the present time, NASAcontrols this problem by rejecting anything which seems toxic. Commercial firms will not release all of their

secret processes to the NASAmanagement who must respect the public's right of

disclosure. Therefore, ways must be developed to handle any toxic substance

without prior knowledge of its concentration and even of its existence. Alarm

systems will be needed since the crew is essentially sleeping in the contaminated factory. Similarly, fire control is an important aspect. Designing a

fireproof habitat seems reasonable from a safety point of view but would be a

near disaster from a human habitation view since it would preclude the use of

personal garments and effects.

One of life's annoyances comes from noise pollution. Exposure to high intensity noise for long periods causes shifts in the auditory threshold and eventually deafness. The problem is intensified since the worker is unable to go

home for 16 hours to get away from the noise of the workplace. This means no

recovery each day so that the sound level must be safe for 24-hour living. On

the other side, an environment that is too quiet can be a problem because

attention is drawn to any sharp, random noise. The Space Station must be like

a hotel with just enough white noise background to afford comfort, particularly at night during sleep. The ventilating fans, teletype machines, etc.

all cause noises which can be unnoticed or disturbing depending upon other

noise in the environment. When the noise is unpleasant or too loud, it will

be necessary to use sound dampening blankets. Ideally, noisy equipment should

not be used.

To maintain adequate motivation of the crew, it will be necessary to concentrate on the little things of life which make living in a remote, hostile

environment bearable. Those who arrange living accommodations on remote drilling rigs and supertankers realize this and give the crews a living style that

4
except for separation from family and friends is often better than at home.

This includes food, clothing,and quarters. A bare-barrackstype habitation

module will not encouragethe highly skilled personnelto return for multiple

tours. It could encourageabherentbehaviorthat will becomea problem to the

command structure. To the present, of necessityNASA has designed the crew

food, furnishings,and clothingwith operationalconsiderationsin mind rather

than personal comfort and enjoyment. With Space Station, the long duration

and repeatedmissionswill require that NASA maximize the enjoyment from the

surroundings. It may even need to allow personalclothingto be used during

duty hours. Varietywill be the watch word if boredom and dissatisfactionare

to be prevented. An army travels on its stomach, the old adage goes. An

absolute requirementwill be tasty, noninstitutionalfood served in pleasant

surroundings. The tastes of a variety of pallatesmust be respected.

Personalsatisfactionis gained from being able to communicatewith familyand

friends using a private system which is both accessible and reliable. This

allows a crewmemberto solve family problems and remove doubt and worry about

family life.

Lastly, the Station personnelwill have unobstructedviews of Earth and the

heavens. This will be an ideal place to hold classes and teach everything

from astronomy to zoology. The scientists onboard offer the world a rich

source of talent which can be used to teach. Plans should be made early to

give the Station methods to transmit lectures to the ground and for the lecturer or teacher to receive feedback from the students. One can imagine an

open university with highly talented scientists teaching courses in their

field during their 90-day stay. Seminarsdesignedto discuss the ongoing scientific program would both improve and hasten the scientific output. The

stimulationof students vastly increasesthe scientist'sknowledgeand efficiency. Teachingcourseswill allow the professorto use free time in productive work rather than in leisure activities which could lead to boredom,

depression,and feelingsof loneliness.

5
Materials Processing

MEDICAL AND BIOLOGICAL RESEARCH

Typical research activities to be performed on the Space Station

will include physiological investigations of humans and animals,

and materials processing.
MEDICALANDBIOLOGICALRESEARCH

Bernard J. Mieszkuc and John B. Charles

I nt rodu ct i on

Research activities aboard the Space Station will have several main areas of

focus. Industrial and commercial activities are areas that will benefit from

the microgravity, high vacuum and thermal extremes available in low Earth

orbit, and will be accorded high priority in terms of resources. One of these

resources will be the presence of human operators. Understanding human adaptation to the orbital environment and the implementation of an appropriate

health maintenance program are high priorities. Basic biological research

will contribute to the knowledge of physiological responses to spaceflight.

Research will also be required for the development of a closed-environment

life support system which should decrease the expense of Space Station operations. Someof this biological research will probably be deferred until dedicated facilities are provided. Basic scientific research in the physical

sciences and astronomy will share personnel and equipment with the applied

research activities in order to conserve resources.

The presence of humans in the space flight environment requires implementation

of a medical program which will ensure their health. Previous spaceflight

experience indicates that weightlessness can present serious physiological

problems to crewmembers, including but not limited to those listed in the

Table. Research in connection with current Space Shuttle flights will provide

insight into some of these problems. However, Space Station activities will

make possible a more thorough study of these and other space flight-related

physiological problems.

Discussion

The proposed life sciences research program on the Space Station will be

coordinated with the health maintenance program. The level of research activity will be determined by the Space Station configuration that is available,

since a modular growth of the station is anticipated. Inside the initial configuration, a single module docked to an orbiter, research will consist of

observing and monitoring the crewmembers, as well as collecting and storing

physiological samples such as blood, urine, and feces for analysis after

returning to Earth. An additional module will expand the research activities

to include on-orbit processing of these samples. The availability of additional work and habitation areas will permit sophisticated medical facilities

similar to those available in a one-physician clinic, with added capabilities. This area will be used for health maintenance and clinical research.

Dedicated habitats and laboratories separate from the health maintenance

facility will be required to conduct large-scale research with animals and

plants. Of particular interest are the physiological effects of microgravity on organisms and the role gravity plays in the function of biological

systems.

To implementthis research,the Space Stationmust provide certain basic capabilities such as the resources to maintain the physical and psychological

7
SOME TOPICS FOR PHYSIOLOGICALRESEARCHON THE SPACE STATION

Redistributionof body fluids

Excessiveexcretionof electrolytes

Altered circulatinglevelsof hormones

Cardiovasculardeconditioning,cardiacmuscle changes

Reduced red blood cell mass

Changes in red blood cell morphology

Loss of muscle tissue and negativenitrogenbalance

Possiblesuppressionof immunologicalsystems

Bone demineralizationand negativecalcium balance

Vestibularfunction- otolithsand semicircularcanals

Vestibularocular and posturalmuscle reflexes

Gastrointestinalfunction,esophagus,stomach

Visual acuity

Pulmonaryfunctionand perfusion

Dysbarismin microgravity

Thermal regulation

Sweating

Pulmonaryparticleclearance

Psychologicalaspects of orbital living

8
well-being of crewmembers,some measurementof crew health and performance,

onboard storage of experimentalspecimens,and two-way real-timetransmission

of video and other data between orbit and Earth. As the Space Station

evolves, other capabilitiesshould be added, such as limited onboard sample

processingand analysis capability. Also needed is the ability to modify and

upgrade equipmentfor medical and experimentalprocedures,and provisionsfor

the maintenanceof simple plants and small animals for periods of 30 days to a

year. Finally,a larger biologicalresearchfacility should permit automatic

or semi-automaticoperation of plant and animal habitats. Crew visits will

probably be required. An onboard centrifuge would provide "pseudo-gravity"

for experimentalcontrols and low-gravityexperiments. Ground-basedfacilities requiredto support the inflight studies include appropriatefacilities

for animal and plant-holding. Data analysis and laboratoryfacilitieswill

also be needed.

In addition to aiding the study of the physiologicaleffects of weightlessness, laboratoryfacilitieswill permitthe developmentof advanced life support systems and controlledecology life support systems (CELSS). Although

the Station will require periodic resupply,many consumablesmay be regenerated on the Station, thereby saving the cost of some Shuttle flights. The

Space Station will have a continuing program of technology and subsystem

developmentto improve life support systems. A major problem for a CELSS is

the recyclingof metabolicwastes to produce food and other consumables. Current efforts are related to the photosyntheticproductionof food and oxygen

by higher plants and algae. Research will be directed towards understanding

the fundamentalsof these and other biologicalprocessesand their adaptation

to weightlessness,as well as the interactionsof biologicalsystems with the

spacecraftenvironment.

Research laboratoriesalso will be available for industrial and commercial

activities,like materialsprocessing,with the potentialfor importantscientific breakthroughsof high economic return. Such investigationswill take

advantage of the extended microgravity of orbital flight and the ultrahigh

vacuum present in unlimited quantities. Specific areas include biological

preparations;electronicmaterials;glass and ceramics;physical processesin

fluids; and chemical,electrochemical,and metallurgicalprocesses.

Recommendations

Since it will be the researchersthemselveswho determinethe details of commercial and scientific research,they must be encouraged to generate recommendations early enough to take advantageof the flexibilityof the initial

stages of Station design. Similarly,the long lead-timesinherentin equipment developmentnecessitatethe timely definitionof hardwarewhich cannot be

met by off-the-shelfequipment.

During Space Station operations,provisions should be made for the routine

and speedy incorporationof new knowledge into ongoing efforts. Special

attention should be paid to the proper interrelationshipof on-orbit activities. The very featuresof Earth orbit which make it attractiveto industrial

and scientificendeavorswill influencethe physiologicalcapabilitiesof the

human investigators. A continuing program of research into the biological

effects of microgravityis absolutelynecessaryto maintain the productivity

and morale of Space Station personnel.
EXTRAVEHICULAR ACTIVITIES

Pressure suits will be maintained, cleaned, repaired, and refurbished

onboard the Space Station. Extravehicular tasks of resupply,

inspection, and repair will be accomplished with the aid of portable

work stations providing restraints, tools and information systems,

and by remote controlled mobility units for transportation of the

crewman and his equipment.
EXTRAVEHICULARACTIVITIES

James M. Waligora

Introduction

Extravehicularactivities (EVA) refers to excursions by crewmembersoutside

the cabin environmentin a pressuresuit. The experienceof Skylab has demonstrated the value and versatilityof EVA in terms of planned resupply and

maintenance of spacecraft as well as in repair of disabled spacecraft systems. It is anticipatedthat there will be extensiveEVA activityoriginating

from Space Station, possibly on a daily basis. Types of EVA activity will

include refueling and refurbishmentof satellite and Shuttle, repair and

refurbishmentof Space Station components,and fabricationof structuresoutside the Space Station. It is likelythat structurefabricationwill be automated, but EVA will be requiredfor inspectionof work and repair of robotic

fabricators.

Discussion

As depicted in the figure on the facing page, the componentsof an EVA system

will include a pressure suit; a life support system, either in backpack form

or, more likely, integralto the suit; a work station to provide crewmember

restraint, tool storage, two-way communicationwith an informationretrieval

system; and a remotecontrolled,summonablemaneuveringsystemthat will allow

free movementof the EVA crewmemberin the vicinityof the Space Station.

The crewmembermust be able to move freely from the spacecraftenvironmentto

the pressure suit environmentwithout prebreathing to prevent decompression

sickness. The Table presentsseveral combinationsof cabin and suit pressures

that could be used and still allow free movement of the crewmember from one

environmentto the other (in some cases, after preconditioningto the Space

Station pressure).

Appendix C presents the rationalefor analyticallyarrivingat these combinations. These combinationsare all equally acceptablein terms of the physiology and medical well-beingof the crewmembers. The primary trade-offwould

appear to be betweenthe increasedflammabilityof materialswith increased02

concentrationat low cabin pressuresand the reductionof arm and leg mobility

at increasedsuit pressures. The pressuresuit must also protectthe crewmember from ionizingradiationboth in low Earth orbit and in higher orbits out

to and includinggeosynchronous. The use of hard rather than soft suit components may provide the needed reductionprotection. The face plate of the

suit must also protectagainst UV radiation.

Recommendations

In view of the extensiveparticipationin EVA by a few of the Space Station

crew it will be essentialthat the suit incorporatefeaturesto minimize crew

fatigue. These features should include maximizationof mobility and ease of

work in the suit, as well as a quick donning and doffing capabiityto minimize

"overhead"time at the beginningand end of EVA. Quick doffing and donning

II
PRESSURESANDPREBREATHEUSEDTO PREVENT

ALTITUDE DECOMPRESSIONSICKNESSIN SPACEFLIGHT

Pressure psi Oxygen % Prebreathe

Gemini Launch 14.7 100%

3 hr @14.7 on 02

Orbit 5.0 100%

None

EVA 3.7 100%

Apollo Launch 14.7 100% 3 hrs @14.7 on 02

Orbit 5.0 100%

None

EVA 3.9 100%

Skyl ab Launch 14.7 100% 3 hrs @14.7 on 02

Orbit 5.0 100%

None

EVA 3.9 100%

Shuttle STS Launch 14.7 20% None

1 hr @14.7 on 02

Orbit 14.7 - 10,2 20 - 26% \

12 hrs @10.2 on 27%02

+ 40 min on 100%02

EVA 4.3 100%

Russian Launch 14.7 20%

Spacecraft None Orbit 14.7 20%

40-60 min @14.7 on 02

EVA 5.8 100%

12
would allow a "lunch break" approach to long EVA's; however, improved insuit

food and waste management systems should be an option for those situations

where a long, unbroken EVA is required.

The pressure suit will be required to have a long service life. In addition

it must be constructed in a manner that will allow it to be resupplied, maintained, repaired, cleaned, and refurbished on-station, as illustrated in the

figure. These requirements will favor the use of hard components, modular

design, simplified maintenance, and the development of sizing systems to maximize interchange of suit parts. The suit must be designed for easy cleaning

to reduce buildup of microbiological flora. The development of washing and

drying facilities, the use of bacteriostatic materials, and provision for a

sterilization or partial sterilization capability will be required.

The Space Station EVA airlock should be designed in consideration of the fact

that, despite precautions to prevent altitude decompression sickness, some

probability of its occurrence will remain, particularly after use of contingency pressures of either the cabin or pressure suit. The treatment of choice

for altitude decompression sickness is the application of hyperbaric pressure. To provide this treatment capability, the airlock should accommodate

two occupants, and allow its pressurization to 2.8 atmospheres with 100%oxygen, the standard treatment pressure for altitude decompression sickness.

COMPATIBLECABIN& SUIT PRESSURESTO ALLOW

FREEMOVEMENTFROMONEENVIRONMENTTO THE OTHER

Cabin Pressure Suit Pressure

psi psi Max 02% Constraints

14.7 8.0 26 None.

11.6 5.75 34 Stay at 11.6 psi 72 hrs prior to

EVA.

10.2 4.8 38 Prebreathe 130 min prior to going

to 10.2. Stay at 10.2 psi 72 hrs

prior to EVA.

9.4 4.3 40 Prebreathe 220 min prior to going

to 9.4. Stay at 9.4 psi 72 hrs

prior to EVA.

7.5 4.3 48 Prebreathe 460 min prior to going

to 7.5. Stay at 7.5 psi 8 hrs

prior to EVA.

13

NEEDFORBIOBEHAVIORALSERVICES

Leonard Gardner and Gary R. Coulter

Introduction

NASA's biomedical operations and research programs continue to evolve to meet

the novel challenges and needs required to support new space systems and missions. The purpose here is to acknowledge and call attention to the importance of an aggressive operationally-oriented program to deal with biobehavioral and psychosocial aspects of a space station. New and more complex space

station systems and unique mission requirements dictate the need for evaluation, research, planning and implementation of such a program to be incorporated early in overall system development. Factors underlying the exigency

for a prominent role for biobehavioral and psychosocial planning are longer

missions, heterogeneous crews, role diversification, changes in command and

social structures, and the importance of habitability considerations.

Discussion

In addition to career astronauts, Space Station personnel might be expected to

include persons selected from outside the astronaut corps such as academic

research scientists, construction engineers and workers, private sector commercial research and development scientists and technicians, and Department of

Defense personnel. Such a mix will likely be necessitated by budgetary and

user requirements. Thus, NASA's previous independence in personnel selection

and mission assignment may necessarily evolve into collaborative decision making with outside agencies or companies. To derive maximumvalue from NASA's

operational experience, it seems that establishment of specific biobehavioral

standards and guidelines would be an approach worthy of serious consideration. It is inevitable that, heterogenous crews and mission roles, a less

hierarchical, more egalitarian organizational structure will evolve having an

impact upon both flight and ground command structures. Long missions and

specific psychosocial patterns (between crewmembers and between the crew and

ground control) also will greatly influence traditional authority structures.

NASAprograms have relied successfully upon operational experience and common

sense without detailed biobehavioral and psychosocial planning. The need was

obviated largely by establishing a prestigious career professional astronaut

corps selected principally from exceptionally qualified military flight crewmen, adhering to a vertical commandstructure, small crew size and/or shortduration missions. With the Space Station, these factors will change. The

spirit of adventure will be modulated by mundane routine; the need for personal privacy will increase; separation from family and emotional support

resources will intensify isolation and intra- and interpersonal tension;

options for physical, leisure, and social activities will be restricted and a

likely source of irritation and complaint. These and others will be influenced by crew interactions compatibility and cultural, sexual, and social

makeups which can be catalogued under "habitability." Thus, the novel conditions on the Space Station strongly suggest that operational decision making

will greatly benefit from, and indeed require, more specific psychosocial and

behavioral information and planning in order to minimize potential problems as

well as to maximize the achievement of mission objectives.

15
SPACESYSTEMSANDMAN, THE OPTION: INTERFACINGOR INTEGRATION

16
The complex systems,mission requirements,and crew productivitywill be much

more highly interdependentonboard the Space Station and can be optimizedwith

greater reliabilityif biobehavioralfactors are evaluated and incorporated

early in program development. Human factors and man-machine interfacingare

necessary but not sufficient. Biobehavioralinput can positively augment

these areas and contribute information essential to personnel selection,

assignment and training decisions. Individualability to complete tasks and

crew productivitywill depend in large measure upon such factorsas stressand

isolation to]erance, psychophysiologicadaptability,emotional self-control,

family situation and stability, personality style, small group interactive

skills, adaptive competenceand others. Psychologicaland biobehavioraldata

which characterizethese elements can be obtained and integratedto maximize

crew compatibility,adaptability,productivity,and mission accomplishment.

Recommendations

The advantage of having behavioralinformationavailable has been stressed.

However, the operationalrelevanceof such informationmust be underscored.

An operationallyfocused role for biobehavioralmedicine is recommended. A

biobehavioral operations group service would include the following:

assessment of system mission requirements from a comprehensivebehavioral

perspective;profilingcrew characteristicsto optimizeselection,assignment,

and training decisions; providing biobehavioral training in physiologic

self-regulation as a space adaptation countermeasure;training in stress

management; providing psychoeducation in small group dynamics, conflict

resolution, diffusion of emotional intensity and frustration, facilitating

intra- and interpersonal harmony; providing ground-based support and

behavioral ombudsmen for crews as they interact with mission control; and

providing general and specific recommendationsregardingpsychosocialaspects

to habitabilitydesign groups.

The inclusionof relevant,operationallyfocused biobehavioralinput in the

program developmentand operationof a Space Station would be a further example of NASA's biomedicaloperationsand research meeting the needs of a new

space endeavor.

17
MEDICAL CARE

A physician monitors an ill crewmember in the Space Station

Health Maintenance Facility (HMF). The HMF is equipped with

state-of-the-art clinical bioinstrumentation, diagnostic imaging,

clinical laboratory, life support hardware, minor surgical

capability, and general pharmacy.
MEDICALCARE

Joseph C. Degioanni, James S. Logan, and Michael A. Reynolds

Introduction

Inflighthealth care is an absoluterequirementfor mission success. On-orbit

medical care will promote crew safety and maximize performance. An inflight

Health MaintenanceFacility (HMF) could also prevent the unfortunatescenario

of an unscheduledrescue mission for medical reasons. The estimatedminimum

time necessaryto effect a rescue of an ill or injured crewmember from the

Space Station may be 15 to 21 days. The impact of such an unscheduledemergency flight would be significantin terms of timelines,manpower,and costs.

In all probability, an illness of sufficient severity to warrant a rescue

attempt would resultin patient demise prior to a "successful"rescue. Therefore, inflightmedical care capabilitiesare essentialto crew health, safety,

and overallmission objectives.

Discussion

As mission complexity, duration, and crew size increases, the probability of

significant inflight medical events increase. Therefore, flexibility must be

inherent in the design of the HMF. It should be a dynamic facility on system,

able to constantly change, so continuing improvements in medical science can

be incorporated. In addition, a dynamic system can easily be adapted to provide medical support for unforeseen problems which may arise secondary to

spacecraft and environmental or operational hazards (see table I, Summary of

Hazard Assessment). Of special interest are improved methods to predict, prevent, and control infectious disease inflight and evaluate the impact of lowlevel chronic exposure to toxic substances. In addition, the role of occupationally induced disease must be investigated and ameliorated.

In considering the appropriate diagnostic and therapeutic capabilities to be

available on-orbit, the concept of the "acceptable medical risk" must be

defined. For example, the treatment for appendicitis is an appendectomy.

However, the capability for major abdominal surgery in early space stations

will not exist. With proper diagnostic and therapeutic tools, a crewmember

might be maintained until a rescue mission returns him/her to Earth for definitive therapy. Without inflight medical support capabilities, a rescue mission for appendicitis would probably be made in vain. On the other hand,

uncomplicated cases of diverticulitis (inflammation of the colon) or cholecystitis (inflammation/infection of the gallbladder), once diagnosed, could be

successfully treated inflight. The inflight medical capability will be

equivalent to a level IV emergency medical facility unless a physician is

present aboard the Space Station in which case the facility is upgraded to

level III (see appendix--Classification of Emergency Services according to the

Joint Commission on Accreditation of Hospitals, 1984).

Low weight, low volume, fully automated diagnostic laboratory equipment must

be included in the HMF. Routine clinical chemistry, hematology, microbiology,

urine analysis, and toxicologic monitoring are essential. In addition,

19
TABLE 1 - SUMMARY OF HAZARD ASSESSMENT(REF.NASA TM 58248)

- SPACE SICKNESS,EARLY MISSION AND INTERMITTENTLYDURING LATE MISSION

- DYSBARISM,JOINT BENDS, CEREBRALBENDS

- OXYGEN DEFICITSAND EXCESS (OXYGENTOXICTY)

- EXPOSURETO TOXIC SUBSTANCES

Acute -hypoxia (e.g., CO, CN, etc.), chemical burn, cryogenicburn,

allergy,,pneumonitis/pulmonaryedema, neurologicalsymptoms

Chronic - pneumo/nitis,neurological deficits, gastrointestinalpathology_'_scel laneous

/

- INFECTION: DERMAL, RESPIRATORYTRACT, PULMONARY,URINARYTRACT, FOODBORNF '

- ELECTRICSHOCK

Burns

Cardiac Dysrhythmias

- RADIATION (PolarOrbits Primarily)

Acute SublethalDose nausea,vomiting,hematologicaldepression

Acute MidlethalDose above + death in approximately30 days

Acute High Dose above + gastrointestinaldenudation+ death in

approximately1 week

Chronic Dose

(MultipleMissions) increasedrisk of leukemia,cancer, cataracts,

and other late effects

- EMBOLISM,THROMBOPHLEBITIS

- TRAUMA

Minor -small lacerations,contusions,abrasions

Moderate - foreign body in the eye, deep lacerations, concussions,

fracturesof small bones of hand and foot

Major -fractures of long bones, ribs; skull fractures (includes

subdural/epiduralhematoma); penetrating injuries of visceral cavities; blunt thoracic, abdominal,musculoskeletal

injury;joint instability;spinal problems

- BURNS - MAJOR AND MINOR

- THERMAL HEAT EXHAUSTION,FROSTBITE

- OCULAR UV BURNS

- BLOOD VOLUME - EXCESS EARLY, DEFICIT LATE

20
physical exam equipment (stethoscope,etc.), EKG, EEG, and some form of

diagnosticimagingare required.

Besides treatingthe routinemedical conditionsexpectedto occur during space

flight (see appendixD), the capabilitymust exist to deal with acute critical

care and trauma situations. Serious injuriesand illnessesrequiringsurgery

will be less probable but potentiallymore dangerous. To a first approximation, the probability of such events can be estimated from experience on

nuclear submarines. During 7,650,000man-days of Polaris submarinemissions

in 1963-1973(see appendix E), there were 269 general surgery cases, of which

6 requiredtransfer at sea and 70 were appendectomies. By comparison,eightman Space Station crews would accumulate 2,920 man-days in a year's operation. On the basis of crude proportionality,one could anticipatea need for

surgery once every 9 or 10 years and an appendectomyabout every 35 years in

space. A total of 44 patientswere transferredfrom Polaris submarinesat sea

for all reasons during 1963-1973;this could correspondto one case requiring

evacuationin about 60 years for the Space Station providedthat crew physical

health, age, occupationaltasks, and living conditionsare similar.

The capabilityto deal with acute critical care and trauma situationspresupposes intravenousaccess, basic and advanced cardiac and pulmonarylife support capability,and minor surgery/anesthesiaequipment. A two-personhyperbaric treatment chamber to treat decompressionsickness should be an early

requirement. The need for physiologicalmeasurementsto study human adaptive

changes to microgravitysuch as SAS must be taken into accountwhen specifications are made up for the diagnostictools to be provided in the Space Station's medical equipment. Since these studies will also need a trained observer, it is likely that a physician, preferablya trained surgeon, will be

needed in every crew to perform the dual function of caring for the crewmembers' health and observingthem as subjectsfor research.

Recommendations

It is recommendedthat an area dedicatedto the HMF be includedin the initial

Space Station module. In addition,it would be desirableto design the galley

and dining room so that either might be made to serve as an emergencysurgical

area with adequate lighting,suction,oxygen, etc. The area should be made to

allow it to be isolatedfrom other crew activitiesand sterilizable.

Realisticrequirementswill be developedfor a level Ill Emergencydepartment

capability similar to the Skylab facility for early missions,and particular

emphasis will be given to identifyingstate-of-the-artdiagnostic and therapeutic devices. High priority medical procedures/techniquessuch as minor

surgery, tissue and sample handling, and drug therapy in the Space Station

environmentneed to be identifiedand developed.

It is desirablethat the HMF of the early Space Station contain provisionsfor

the storage and retrievalof medical data from its scientificcrews. The full

extent of physiologicalchanges resultingfrom long-termspace flight can only

be deteminedthrough measurementsmade on a large populationof Space Station

inhabitantsby surveyingliterallyevery crew until the data was obtained.

21
MAINTENANCE OF DENTAL HEALTH

The risk of a dental problem in flight can be met utilizing the

medical facilities. The position of the patient can accommodate

the convenience of the operator in a microgravity environment.
MAINTENANCEOF DENTAL HEALTH

William J. Frome

Introduction

In NASA's Manned Space Flight Program, provisions have always been made for

treatment of unanticipated dental problems inflight. The earliest flights--

Mercury, Gemini, and Apollo--were all of short duration and the provisions

were minimal. Skylab, however, presented missions ranging from 28 to 84 days

in length. For the Skylab series of flights, a more complete dental treatment

capability was developed. Considerations of dental health will continue in a

more sophisticated manner as NASAconsiders the Space Station Program.

Discussion

The risks of a crewman developingan inflightdental problem severe enough to

compromisehis ability to functioneffectivelyhave been calculated. Based on

studies of the astronautpopulation,it is estimatedthat the risk is approximately 1 percent for each 90 man-days. That is equivalentto a problem of

that severityoccurringonce every 24 years for an adult apparentlyin excellent dental health.

Dental problems most likely to appear are toothache (with or without swelling

due to pulpitis or periapicalabscess),peridontalabscess, or fracture of a

tooth during normal function. Trauma in the space environmentmust be considered also. Dental decay would not be expected to be a considerationprovided

there continuesto be the intensedental supervisionof crewmembersduringthe

preflightperiods. Lesser problems,such as chipped teeth, fracture restorations, or benign oral soft tissue lesions would be expected to occur at somewhat more than twice that frequency. These lesserproblemswould not affect a

crewman'sability to perform and would not be expectedto increasein severity

with time. However, it is expected that crewmemberswill include nonastronauts whose dental history is less well-known. It is probablethat risk estimates for those personswill be higher than for astronauts.

The dental treatmentcapabilityfor Skylab consistedof developinga training

program and the equipmentto treat problemsof a complexityup to and including tooth removal. To accomplishthis, training sessions included lectures

and actual clinical experiencesin the appropriateprocedures. Manuals were

written to aid the astronauts inflight and arrangementswere made for diagnosis and directionas needed from the mission control .

A general impressionis that while the philosophyand treatmentcapabilities

of Skylab should be retained,significantimprovementsshould be made in the

inflightfacilities,equipment,and training. Preliminarysuggestionsinclude

a designatedtreatmentarea with proper lighting and restraintsfor both the

patient and the clinician or the dental aide. In consideringrestraintsto

movement,it should be pointed out that considerableforce is requiredin some

dental procedures:tooth removal,for instance. Suction also should be available as well as a more extensivecollectionof equipmentand suppliesthan was

present in Skylab. A more completetreatmentcapabilitywould be usefulonly

23
I

/

I

!

6 I/

% Risk per /!// _i

90 days //_

I 2 3 4 5 6 7 8 9

Crewmen

The risk of a dental problem which might compromise a crewman's ability to

function is 1% for each 90 days under ideal conditions which include continuous preflight dental prophylaxis and care.

The solid line is predicted from past experience with the astronaut corps and

their use of Flight Operations Dental Clinic.

The hypothetical line is predicted if nonastronauts would become crewmembers

and who have not had available adequate dental care prior to the mission.

Figure 1

24
if at least one crewmember with a background in biomedical sciences were to

receive intensive training and extensive preflight clinical experience rather

than minimal training for all crewmen as in Skylab.

Questions remain about treatment of dental problems in the microgravity environment and attempts to answer them should be made before a Space Station is

inhabited on a permanent basis. These include operative problems that might

occur in the oral area where saliva and blood might float freely rather than

settle to the floor of the mouth. A separation of the debris could be serious. The difficulties in applying forces necessary for tooth removal in a

microgravity environment should be explored, especially regarding restraints.

Oral wound healing in the space environment should be confirmed. Information

on factors such as bleeding and blood clotting involving both bone and soft

tissue would be pertinent. Invaluable clinical experience and knowledge could

be gained by experimentally removing teeth, probably in animal subjects. The

use of local anesthesia in the microgravity environment should be evaluated.

It could be hypothesized that in a microgravity environment the patients would

be less prone to syncope--they would always effectively be in a prone position. Without the effect of gravity, anesthesia solutions would diffuse more

uniformly in the tissues but might be more difficult to deliver without

including bubbles.

Living in a microgravity environment could be stressful to unexperienced crewmembers. The probability exists that these individuals could develop or

experience clinically significant exacerbation of their peredontal disease.

The drawing accompanying this article suggests a potential concept. In treating patients, it may be possible to liberate ourselves from some of our earthbound traditions. Since up and down are no longer meaningful with microgravity, we can position the patient for the maximum convenience of the operator.

As can be seen in the drawing, the upper jaw in relation to the clinician has

now become the lower jaw and viewing ability as well as operator access is

remarkably improved. Other opportunities to capitalize upon the uniqueness of

the space environment undoubtedly will be discovered.

Recommendations

The following recommendations are made concerning dentistry in the Space Station:

a. In planning for a medical treatment facility, consideration should be

given to the unique needs of providing adequate dental treatment. The facilities used for medical treatment could be adapted to dental treatment.

b. At least one individual crewperson should receive intensive preflight

training in providing crew dental treatment in the space environment.

c. Wound healing must be investigated in the space environment. It

would seem that tooth removal might be a promising method for this study as it

is a relatively benign procedure and involves manipulation and healing of both

bone and soft tissue.

25
MAINTAINING HEALTH THROUGH PHYSICAL CONDITIONING AND

COUNTERMEASURES

Exercise will be utilized for recreation, physiologic testing, and

maintenance of cardiovascular function and peripheral muscle

tone. It will be supplemented by other techniques, such as lower

body negative pressure and pharmacological techniques.
MAINTAININGHEALTHTHROUGHCONDITIONINGAND COUNTERMEASURES

Michael W. Bungo and John B. Charles

Introduction

The well-being of Space Station personnel requires attention to their physiological and psychological adjustments to the conditions aboard the Space Station, and to their readjustments to life on Earth after their return. One of

the primary concerns is the physiological adaptation to weightlessness, in

terms of its effects both inflight and afterwards. This adaptation includes

the loss of skeletal calcium, of muscle mass and nitrogen stores, and of red

cell mass and blood volume. Also, decrements in exercise capacity and orthostatic tolerance are seen after extended periods of weightlessness. Each of

these changes is a predictable physiologic response to the reduced physical

stress of life without gravity and is also a serious impediment to the resumption of regular activities on Earth.

Discussion

Previous efforts to counter the adaptive changes in space flight have centered

primarily on exercise as a means of providing the musculoskeletal stress that

is otherwise absent in weightlessness (see table). This work had made use of

traditional exercise modalities,_ each having strengths and weaknesses in this

application. For example, the bicycle ergometer used on Skylab provided for

the maintenance of cardiorespiratory exercise capability, and also temporarily

relieved the uncomfortable effects of the headward fluid shift. However, it

was inadequate for the maintenance of skeletal muscle exercise capacity and

mass. A weakness commonto all of the methods has been the time required for

any beneficial effects to be obtained. A single exercise may require several

hours or more of daily use to be effective. The time problem is compounded by

the number of different exercises required to maintain the desired degree of

physical fitness, and the additional time spent on assembling and disassembling the necessary equipment and on personal hygiene afterwards. The total

time commitment will be a significant fraction of the workday, which might

otherwise be devoted to the activities initially necessitating the individual's presence aboard the Space Station.

Methods other than exercise have been investigated to counter the orthostatic

hypotension commonly observed in astronauts immediately after flight (see

table I). The use of an antigravity garment to provide lower body positive

pressure protected the Skylab astronauts from the consequences of blood pooling for several hours after their return. It was, however, a simple mechanical construct which did nothing to restore normal physiological function.

Such restoration has been attempted through various other means. Intermittent

thigh cuff inflation inflight, to promote blood pooling in the legs and thus

preserve both circulating volume and vascular smooth muscle tone, proved to be

ineffective during space flight. Experiments on returning Shuttle astronauts

indicate that simple oral rehydration with an isotonic saline solution, to

replace some of the lost plasma volume before atmosphere entry, provides a

significant degree of protection from orthostatic hypotension following

weightlessness. Ground-based studies combining rehydration with lower body

27
TABLE I - MICROGRAVITYCOUNTERMEASURESINVESTIGATEDIN SPACE FLIGHT

METHOD GEMINI APOLLO SKYLAB SALYUT SHUTTLE

Exercise

Isotonic Exercise X X X X

Bicycle Ergometer X X

Running Board, Treadmill X X X

Non-exercise

Thigh cuffs X

Anti-gravity garment X X

Saline loading X

Saline loading plus LBNP X

28
negative pressure suggest that a more prolonged rehydration and a larger

sequestered volume can be obtained. This process has apparently been used

with some success by Soviet cosmonauts at the termination of their extended

stays aboard the Salyut space stations.

It should be noted that the exercise and non-exercise methods tested have not

eliminated the wasting of the musculoskeletal system, nor have they counteracted the development of post-weightlessness orthostatic intolerance. Whether

these results could be improved by more intense application of the methods

described, or will require countermeasures yet undeveloped, must be determined

by future research.

Recommendations

It must be recognized from the outset that, for the physiological well-being

of the Space Station personnel, allowance must be made for an on-going program

of physical exercise. The substantial daily time commitment must be weighed

against an enhanced productivity when the individual continues his preflight

regimen of physical exercise. Exercise will provide an outlet for the emotional upsets and frustrations to be expected during an extended stay in an

unusual environment, under strong pressure to achieve results, and away from

the support of family and friends. The crewmember's motivation also will be

enhanced by the realization that, through physical conditioning, a speedy

return to normal life on Earth will be possible.

From the foregoing considerations, a hypothetical physical conditioning and

countermeasures prescription can be outlined. The planned exercise program

will include loaded treadmill running for the maintenance of cardiorespiratory

exercise capacity. Elastic bungee cords attached to a harness system will

load the individual sufficiently to permit running on the treadmill. Additionally, the continuous impacting of the feet on the treadmill surface may

sufficiently stimulate the load-bearing bones to slow, or even reverse, the

skeletal wasting seen during long space flights. Skeletal muscle conditioning, especially of the arms and trunk, will be accomplished using isotonic and

isokinetic exercise devices. Additional protection of the skeleton and the

musculature may be provided by drug therapy.

An "end-of-tour" regimen will ease the transition back into Earth's gravity.

As currently envisioned, this regimen will commencea week or so before the

return to Earth. Daily exposure to about four hours of 30 mm. Hg lower body

negative pressure combined with oral rehydration therapy, using a saline and

glucose solution, will augment the body's decreased plasma volume and begin

the readaptation of vascular smooth muscle in the legs to the hydrostatic gradients which are absent in weightlessness. The movement of fluid into the

interstitial spaces will also be facilitated, preventing the loss of filtrate

from the circulating blood volume after returning to Earth.

These recommendations are the products of work to date; the details will

surely change in the light of research over the next several years. However,

the general considerations discussed here can serve as a foundation for other

aspects of Space Station design and operations planning.

29
_ PROTECTION FROM RADIATION

\ .

'Schematic representation of the sources of ionizing radiation in space.
PROTECTIONFROMRADIATION

D. Stuart Nachtwey

Introduction

The Space Station is expected to operate in a 28-1/2 ° orbit and at an altitude

of 500 km. In this orbit, the major source of radiation will be the inner,

geomagnetically trapped protons (Inner Van Allen Belt) (see fig.). Most of

the radiation dose from the belt will be received during traversal of the

South Atlantic Anomaly, a region where, because of an anomaly in the Earth's

magnetic field, the inner belt dips down to lower altitudes. The other

sources of orbital radiation--the outer belt, which consists primarily of

energetic electrons, the galactic cosmic radiation, and the radiation from

solar flares--will contribute only a little to the dose because of deflection

by the geomagnetic field.

Discussion

The Space Station will likely have a minimum structural thickness of about 2

g/cm2 of aluminum-equivalent material. Behind a shield of this thickness, at

500 km and 28-1/2 ° , the dose to the skin is about 240 millirad (mrad) per day

and the dose to the bone marrow (5 cm dose) is about 150 mrad/day. Thus for a

90-day tour of duty, a crewperson could receive up to about 22 rad to the skin

and 13.5 rad to the bone marrow and other organs from the trapped proton

belt. Additional radiation to the skin might be received during EVA. A worst

case situation (EVA during the four or so successive passes through the South

Atlantic Anomaly) could add 3 rad to the skin for one 6-hour EVA.

At 28-1/2 ° and 500 km, the geomagnetic field protects against most of the

radiation from solar particle events; only about 1% of the free space dose

penetrates to that orbit. Nonetheless, some very rare but very intense solar

flares have been recorded in free space at about I000 tad. Therefore, the

potential contribution to the total dose from anomalously large solar particle

events must be considered in budgeting crew exposures.

The immediate impact of a nominal mission with about 15 rad/tour is negligible. The potential effect from this dose will be realized later in the crewperson's life mainly as an increased risk of contracting cancer. Although the

risk estimates for radiation carcinogenesis have large uncertainties (about an

order of magnitude) and are dependent upon a number of variables (age, sex,

type of cancer, dose-response model, etc.), a rough estimate of increased

lifetime risk from 15 rad would be 1.5 x lO-J. One would expect 15 deaths

from radiation-induced cancer in 10,000 crewpersons exposed to 15 rad. This

increase represents about 1% of the expected 1640 out of I0,000 (1.6 x I0 -I)

who would normally die of cancer sometime in their lifespan. Multiple tours

would increase the inidividual's risk proportionately. For example, 150 rad

accumulated during 10 tours would increase the risk to 1.5 x 10-2 which is

about 10%of the natural lifetime risk.

The aforesaid value should be viewed in some perspective: 150 rad is calculated to yield, on average, 150 days of life expectancy loss. The average

31
TABLE1 - SUGGESTEDEXPOSURELIMITSAND EXPOSUREACCUMULATIORAT N E CONSTRAINTS

FOE UNIT REFERENCERISK CONDITIONS

Ancillary Reference Risks

Primary

Reference Risk Bone Marrow Skin Ocular Lens Testes

Constraint (rem at 5 cm) (rem at 5 cm) (rem at 0.i ram) (rem at 3 _mm) (=em at 3 cm)

1-year average daily rate 0.2 0.6 0.3 0.I

30-day _a>imum 25 75 37 13

Quarterly m_ximum a 35 105 52 18

YearLy _axi_um 75 225 112 38

Career limit 400 400 1200 600 200

a

Ma_, be allowed for two consecutive quarters followed by 6 months of restriction from

further exposure to maintain yearly limit.

32
safe job (e.g. teaching) leads to an average 30 days life expectancy loss; the

average "less safe" job (e.g. construction and mining) leads to a 300 day

loss. Coal mining leads to a ii00 day loss. If work in a Space Station is

considered as a "less safe" occupation, then the radiation exposure problem

should be viewed in this context.

Heretofore, NASA's Astronaut Radiation Exposure Limits (see Table) were predicated, in part, on the high risks involved in space missions. With experience, the risks of equipment failure are declining. Moreover, since 1970 when

the limits were recommended, more has been learned about radiation effects.

It is not unreasonable to expect that space crew radiation limits may be

revised downward toward the career limits for terrestrial workers, which is

235 rem (equivalent to 235 rad of low LET radiation). This is particularly

true if large numbers of individuals will be exposed to the environment.

The few virtually unshieldable, galactic cosmic heavy particles/day contribute

very little to the overall dose. However, these heavy, charged particles are

so energetic that they can produce a densely ionized track through the entire

body with a consequent track of dead and damaged cells. The biological consequences of such heavy particles are poorly understood, but recent evidence

suggests that they can be very effective in inducing cancer at a later time.

Therefore, although rare, they should be given special consideration and at

least measured separately from the proton belt dose in order that the true

biological significance for human can be calculated.

Recommendations

Should the above discussed consequences of space radiation be unacceptable,

potential countermeasures could be employed: The overall shielding of the

Space Station could be increased, either through dead mass or judicious stowage of water, wastes, equipment, and non-expendable items. (To reduce the

bone marrow dose to half, i.e., 75 mrad/day, requires the equivalent of an

additional 20 g/cm2 of structure.) Partial body shielding of the lower abdominal area (e.g., with a lead-loaded girdle) could be utilized for individuals

likely to conceive after their Space Station tour. Otherwise sheilding of the

bone marrow and lens of the eye should be considered. To protect against a

catestrophic exposure bone marrow banking on Earth could become useful. The

Station could be maintained in a lower altitude orbit. (At STS orbits of

about 300 km, the dose-rate is about 6 mrad/day). Radiation exposure of the

crew could be budgeted to a predetermined acceptable level by restricting number of tours. All of these potential countermeasures require tradeoff studies

to determine the impacts on missions, mass-to-orbit costs, and operational

flexibility. An optimization appears readily achievable. Potential population of proginey and age at the time of exposure could be included in the

allowable limits if lifetime radiation exposure becomes too high for the regulating authorities to readily accept for the population in general.

33
REGENERABLE

Spill \

1"q"

Chemical

Proces=ing

!

REG 4ERABLE

CO2

4,q,

Toxic MolecularSleve

Chemicals " _

1_ CO2 Removed

Material

Offgasslng

ATMOSPHERIC CONTAMINATION CONTROL

Atmospheric contaminant sources and removal in the Space Station.
ATMOSPHERICCONTAMINATIONCONTROL

Martin E. Coleman

Introduction

Toxic chemical contamination of the breathing atmosphere has been recognized

as a potential hazard to crewmembers since the earliest days of manned space

flight. Considering the long period of time that atmospheric contaminants

could accumulate and the great diversity of materials and equipment projected,

the Space Station could present a greater toxicological hazard from atmospheric contaminants than was seen during any of the earlier orbital missions. The principal sources of atmospheric contamination in the Space Station would be as follows:

a. Continuous release (offgassing) of trace amounts of contaminant chemicals from most types of nonmetallic materials used such as plastics, electric

wire insulations, and paints.

b. Escape from containment of liquid or gaseous chemicals from material

processing facilities, cooling coils, and propellant systems.

c. Combustion, thermal decomposition, or heat vaporization of various

materials.

d. Metabolic products released by the crewmembers themselves.

Discussion

The consequences of toxic levels of atmospheric contaminants might include an

increased incidence or severity of space sickness, because many types of chemical fumes increase susceptibility to nausea. The most likely adverse effect

would probably be discomfort caused by eye and respiratory tract irritants.

Somepotential chemical contaminants would cause mental impairment during high

level continuous exposures, perhaps interfering with the performance of complex tasks. Long-term exposure to chemical contaminants could cause an

increased susceptibility to diseases such as respiratory infection or damage

to organs such as the liver and kidneys.

Control of released contaminant chemicals into the Space Station atmosphere

would begin with the selection of flight materials that release minimal

amounts of toxic chemicals through offgassing. Liquid and gaseous chemicals

used in chemical processing facilities, heat exchangers, and other applications would, as much as possible, be maintained in fail-safe containment systems. To the extent possible, areas where these chemicals are used would be

isolated from the remainder of the habitable areas of the Space Station.

Gaseous containment levels in the Space Station would be monitored in several

different ways. Excessive atmospheric levels of carbon dioxide (C02) , carbon

monoxide (CO), and certain other chemicals would set off alarms. Crewmembers

should have eye and respiratory protective devices readily available at all

times for use in the event of excessive atmospheric contaminant buildup.

35
A gas chromatograph-mass spectrometer (GC-MS) system for the analysis of

atmospheric contaminants would be essential to the Space Station. There would

either be a crewmember in the Space Station who was trained in the use of this

system, or the output from the GC-MSsystem would be telemetered back to Earth

for evaluation. The GC-MS system would be capable of detecting very low

levels of thousands of different atmospheric contaminants. It would perform

atmospheric analyses in the Space Station compartment in which it was located

or in atmospheric samples brought in from other compartments.

Atmospheric contaminant removal would be important in maintaining a safe breathing atmosphere in the Space Station. Most, if not all, of the decontaminant

materials should be renewable, if possible, since this would eliminate the

necessity of resupplying them at intervals.

An effective way of removing CO2, a contaminant that would be produced in

large quantities by the crewmembers themselves, is by molecular sieves. The

molecular sieves take up CO2 from the air flowing through them, and can then

be regenerated by heating in the space vacuum to drive off the CO2. These

molecular sieves were used successfully in CO2 removal during the Skylab missions of the 1970's.

Large activated charcoal filters would probably be the primary means of

removal of most organic chemical contaminants from the Space Station atmosphere. Charcoal has a high affinity for most organic chemicals, and like the

molecular sieves, could be regenerated by heating in the space vacuum. Special chemical-treated charcoals would be required for the removal of certain

contaminants such as ammonia and formaldehyde.

Still another means of toxic contaminant removal would probably be through

oxidation. The ambient temperature catalytic oxidizer (ATCO) system is currently used in manned spacecraft to oxidize COto CO2. It probably also oxidizes a number of other organic chemicals to CO2. An oxidation system may be

the method of choice for removing many chemical contaminants that are not

absorbed by charcoal.

Recommendations

Considering the anticipated wide diversity of activities and the long mission

times by individual crewmembers, adequate toxicological control of Space Station atmosphere will be extremely important. Air quality will be controlled

in several ways. Alarm systems will warn of release from containment and of

excessive atmospheric levels of certain chemicals. A GC-MSsystem will analyze atmospheric samples taken from each compartment of the Space Station on a

regular basis and immediately after a suspected chemical spill.

Examples of chemical contaminants that might be released into the Space Station atmospheres, the means of their removal, and the means of regeneration of

several removal systems are summarized in table I.

The measures discussed should ensure a safe, clean breathing atmosphere over a

long period of time, even in the event of unexpected accidents or equipment

failures, for the inhabitants of the Space Station.

36
TABLE1 - ATMOSPHERICCONTAMINANTSOURCESANDREMOVAL

Present day Means of regeneration

Contaminant Examples of means of of decontaminant

source contaminants removal system

A. Offgassing of Organic chemicals

nonmetallic toluene Activated charcoal Heat in space vacuum

materials methylethylketone molecular sieves Heat in space vacuum

ethylbenzene oxidation (ATCO system)* Heat in space vacuum

isopropyl alcohol dehumidifer system Charcoal filtration

of water

B. Chemical Organic chemicals

reactor styrene Activated charcoal Heat in space vacuum

or leaks cadium telluride HEPA filter

C. Biological Glutaradelhyde Activated charcoal Heat in space vacuum

tissue formaldehyde special chemical treated -

fixatives charcoal

D. Combustion or Carbon monoxide ATCO system Heat in space vacuum

thermodecom- hydrogen cyanide activated charcoal Heat in space vacuum

position of smoke particles IHEPA filter

materials

E. Normal res- Carbon dioxide Molecular sieves Heat in space vacuum

piration of carbon monoxide !oxidation (ATCO system) Heat in space vacuum

crewmembers skatole activated charcoal Heat in space vacuum

F. Toxic Metals Cadmium vapor or dust HEPA filter Heat in space vacuum

mercury vapor activated charcoal Heat in space vacuum

G. Chemical Freons Activated charcoal(freons) Heat in space vacuum

components Ammonia phosphoric acid treated -

of flight charcoal (ammonia)

hardware

*Ambient temperature catalytic oxidizer, consisting of platinum-coated charcoal. The

platinum catalyzes the oxidation of many chemicals.

37
ATMOSPHERIC COMPOSITION

The atmosphere within the Space Station will be

controlled to provide the proper environments for crewmembers

and research activities.
ATMOSPHERICOMPOSITION

Herbert R. Greider

Introduction

For the last five years the Space Shuttle program management has been aware of

the possibility of an extravehicular activity (EVA) crewmember developing the

bends when going from a cabin pressurized at one atmosphere with 23% oxygen to

an EVA suit at 4.2 psia and 100%oxygen. The requirement that the EVA crewmember breathe 100% oxygen for several hours at cabin atmosphere has not

solved the bends problem and causes unsatisfactory operational procedures.

Since the Shuttle atmosphere was selected over ten years ago, a fresh look at

Space Station atmosphere selection is needed using the Shuttle experience.

The goal must be an atmosphere combination (cabin/suit) that does not cause

bends and has simple operational procedures with no oxygen prebreathe requirement. Of course, the decision cannot be made without considering the fire

hazard, waste heat removal, structural weight, and equipment complexity.

The main discussion concerns the amount that the partial pressure of nitrogen

can be reduced, which translates into the amount the total pressure can be

reduced. Probably, the partial pressure oxygen can be reduced from the equivalent of sea level (P02=160 mm.Hg) to something like the pressure in Denver

(5000 ft: P02=133 mm/Hg). The only problem that must be considered is that

the Space Station will have a less stable pressure control than Denver. To

compensate for this instability, two factors must be considered: the low side

of the cabin pressure regulation and the added reduction required to activate

the warning system.

Discussion

Altitude bends are caused by a reduction in total atmospheric pressure which

reduces nitrogen partial pressure. The reduction of nitrogen partial pressure

by replacing nitrogen with oxygen will not cause bends when total pressure is

kept constant. Therefore, the best solution is to select a Space Station

atmosphere at an intermediate altitude--such as 1/2 atmosphere--and use a suit

pressure of approximately 4.0 psia, with less loss of hand dexterity compared

to the much-discussed 8.0 psia suit.

During World War II the United States flew 25,000 to 30,000 crewmembers per

day in unpressurized cabins to altitudes between 21,000 ft (6.5 psi-335 mm)

and 27,000 ft (5.0 psi-258 mm) with no apparent operational bends problem and

no need for hyperbaric chambers. Flights of 4- to 7-hours duration at over

21,000 ft were often made on three and four successive days with no ill

effect. Assuming that the oxygen partial pressure remained at sea level normal, the nitrogen partial pressure was reduced from between 433 and 510 mm.Hg.

From this experience, it seems safe to say that the Space Station crews will

be able to go from the sea-level environment of the Shuttle to a one-half

atmosphere Space Station, where the nitrogen partial pressure is reduced by i

372 mm.Hg, with no bends problem and no oxygen prebreathe requirement. The

39
crew would reach equilibrium with this atmosphere in a short time, and then

would be available to go EVA with 4.0 psia suit as frequently as necessary

with no oxygen prebreathe. This would give another change in nitrogen partial

pressure of 228 mm. Hg. The important factor here is that the crewmembers

will make the large change in nitrogen partial pressure (Shuttle to Space Station) only once, at the beginning of their tour. During the 3 to 6-month tour

of duty, small changes in nitrogen partial pressure (Space Station to suit)

can be made many times with no ill effect.

Recommendations

A cabin pressure of 7.4 psi/60% N2 is highly recommended. The key is the use

of intermediate pressure between Shuttle's sea level pressure and the 4.3 psia

suit pressure. The intermediate is selected so that the transition between

Shuttle and Space Station is larger (7.4 psia) (table I). However, this transition will be made only once, at the beginning of each tour of duty. Once

the body has reached equilibrium with the Space Station atmosphere of 7.4 psi/

60% (ca. 24 hrs.), then the crewperson is available to make a second smaller

transition to the suit pressure of 4.3 psi/lO0% 02.

The 8 mm CO2 is selected so as not to put too stringent a requirement on the

CO2 scrubbers. No ill physiological effect is expected because of this selection. The first 24-hour limitation in the Space Station before going EVA is

an estimate of the time required to reach near equilibrium for N2. Some

research is required to determine the equilibrium time. The hyperbaric chamber is of questionable need, but if it is considered necessary, one atmosphere

above Space Station pressure would meet this need (see table).

Other Considerations

Fire hazard is always a serious consideration whether it is a ship at sea or a

Space Station. A 40% oxygen at 7.4 psia will require a somewhat more rigid

material selection than a 1.0 atmosphere cabin. It should not be an overwhelming problem considering that Mercury, Gemini, and Apollo missions were

flown with 100%oxygen at 5.0 psia. Lyndon B. Johnson Space Center (JSC) and

Lewis Research Center (LERC) are looking at the problems with a 7.4 psia cabin

and 40% oxygen. LERC has a Research and Technology Objectives and Plans

(RTOP) on Reduced Gravity Combustion Science and is having a workshop early in

1984 on fire problems in this atmosphere.

Space Station gas leakage and airlock gas losses would be reduced by one-half

compared to a 1.0 atmosphere cabin. This is a very important consideration

because all makeup gases must be carried into orbit. The airlock losses with

many EVA's will be significant. The gas leakage from the EVA suit at 4.3

psia, of course, would be approximately half of an 8.0 psia suit. This must

be one of the considerations in selection of Space Station suit pressure.

Structural weight would be lessened by reducing the pressure to 7.4 psia.

This is not important in a small station but becomes more important as the

stations get larger. This proposed pressure of 7.4 psi must be given serious

consideration as it may affect the space program for many decades. Lower

pressures also reduce the decompression risk.

4O
TABLE 1 - RECOMMENDEDCABIN ENVIRONMENTAND CONSTRAINTS

Cabin Pressure 7.4 psia (18,000 ft)

EVA Suit Pressure 4.3 psia (30,000 ft)

Partial Pressure CO2 8 mm - maximum

Cabin Temperature 65 ° to 80 ° F - controllable

Time from Sea Level One hour minimum and no

to 7.4 Station Cabin prebreathe 02 required

Time in Station 24 hours minimum

before First EVA

Time from 7.4 Station 30 minutes and no prebreathe

to 4.3 Suit 02 required

Repeat EVA's No limitation

Hyperbaric Chamber One atmosphere over Station pressure

TABLE 2 - ALVEOLAR PO2 AND PCO2 VS ALTITUDE IN AIR

Avg pO2 Avg pCO2

Sea Level 102 38

5,000 ft. I 79 37

r

8,000 ft.

ft'l I 70 36

i0,000 61 35

TABLE 3 - OXYGENEQUIVALENTSFOR 18 000 FT TO SIMULATE SELECTEDALTITUDES

Oxygen Concentrations

Sea Level 44%

5,000 ft. 37%

8,000 ft. 33%

i0,000 ft. 30%

TABLE 4 - ALVEOLAR PO2 AT 18 000 FT FOR TABLE 2 ABOVE

02 PERCENTAGESFOR NOMINAL CABIN

REGULATION AND FOR LOWRANGEREGULATION(-20 mm/-O.4 psi)

Nominal pO2 Low Range pO2

Sea Level 102 94

5,000 ft. 79 71

8,000 ft. 70 63

i0,000 ft. 61 55

It is possible to reduce the percentage of oxygen and simulate a higher

altitude as noted in table 2. Airlines fly with an 8000-ft cabin. Table 3

shows that to simulate the 8000-ft condition in an 18000-ft cabin, oxygen is used. It is possible to go to a higher equivalent altitude and

depend on crew acclimatization. The cabin pressure will deviate approximately+__O.2 psi around nominal. Another 0.2 psi must be subtracted to

activate the low pressure warning alarm. Table 4 shows these effects on

the alveolar oxygen partial pressure.

41
NOISE POLLUTION

Although Space Station systems must be designed to ensure

that acoustic noise levels generated will be within specified limits,

periodic noise surveys will be conducted on-orbit. Illustrated

above is a crewperson using a portable sound level meter to measure

noise produced by a mechanical device. A second crewperson is

entering the data into a Io0 which will be returned to the ground.
NOISEPOLLUTION

Jerry L. Homick

I nt roduct i on

During the past 10 to 20 years, an increased awareness of the effects of noise

on man has influenced the design and development of manned spacecraft systems. Where cost, weight, and size are critical factors, a compromise must

often be reached between the desirable and the practical. Nevertheless, in

the future, with the use of more sophisticated vehicles that are intended for

long-duration habitation by a larger number of people, acoustical noise must

be given due consideration as a potential detriment to safety, functional

efficiency, and physical and psychological well-being.

Discussion

Permanent Threshold Shifts (He_r_ng _o_s_

Brief exposure to very high intensity noise or long-duration exposure to moderately intense noise can cause permanent damage to the human auditory system. Well-established damage risk guidelines exist for wide-band and narrowband noise for exposure up to 8 hours. However, in attempting to establish

physiologically safe levels for long duration, continuous noise exposure, certain assumptions and extrapolations must be made. Using the best available

sources of information, it has been determined analytically that continous

exposure to noise levels greater than 76 dBA for periods longer than 24 to 28

hours could cause permanent hearing damage in some individuals.

Temporary Threshold Shifts

A temporary threshold shift is a temporary hearing loss, the magnitude and

duration of which depends on the duration, intensity, frequency content, and

periodicity of the offending noise. Temporary threshold shifts can cause difficulty with signal detection and speech communications. Available data indicate that temporary shifts reach asymptotic levels after the first 24 to 36

hours of exposure. If the offending noise is removed for a sufficient period

of time complete recovery will occur. However, the literature indicates that

if the temporary shift exceeds about 40 dBA, then complete recovery may never

occur. That is, some residual permanent loss will be present.

Sleep Interference

The results of laboratory studies indicate that subtle alterations in EEG

activity occur with noise exposure. Also, as expected, large individual variations in subjective reactions occur. Some individuals have no difficulty

with sleeping in loud noise environments while others are easily affected. It

is widely recognized that intermittent noises are more disruptive of sleep

than are steady-state noises. Large individual variations exist with regard

to the time required to habituate to noisy sleep environments. This is an

important consideration for Space Station. Most crewmembers may become accustomed to sleeping with excessive noise after a few nights; however, in the

43
135

140 DURATION

IN c_

130 \,, 1_1-~_1⁄2, 12_o_

i LIESS ,, z co 83 o

,,,_ 12o \ _ __/ o

o° _\ \.. _--_ o_o_ o

2o° \\ _ 1/ I_7-- _0__

,,,_. / I >>

><>,,,i00 _. _ __./ / 30-- I 95 _-< o,,,_j"'

1:3

_ / I 120 85 _:_

__ ___-_ __.-"_ 480 240 _ -

8o i

IL 75 o

2 3 4 5 6 7 8 9 2 3 4. 5 6 7 89

i00 1 000 I0 000

BAND CENTER FREQUENCY, Hz

Figure 1.- Damagerisk contours for One Exposure Per Day to octave (left-hand ordinate)

and one-I:hird octave or narrower ( right-hand ordinate) bands of noise.

This graph shall be applied to individual band levels present in broad band noise.

44
meantime, their performanceand well-beingmay suffer due to fatigue from the

loss of sleep. Finally, the problems of noise-inducedtemporary threshold

shifts and potentialpermanenthearing loss cannot be minimized. A period of

relative quiet must be provided during the sleep period to ensure adequate

recoveryfrom temporarythresholdshiftsduring the work day.

Annoyance

Annoyance caused by noise is a highly subjectiveresponsewhich can be influenced by a variety of factors includingindividualattitudes,motivation,the

situation in which the noise occurs, and the physical characteristicsof the

noise. The last mentioned variable is the most sensitive region of hearing,

and excessivenarrow-bandnoise in the 1-4 KHz range is to be avoided.

PerformanceDecrement

Limited quantitativedata available in the literature indicate that direct

noise-inducedperformancedecrementsoccur only with noise levels greaterthan

90 dBA. However, indirect noise related performancedecrements can result

from degraded ability to detect accurately and discriminate auditory

information (speech and nonspeech), fatigue resulting from sleep loss, and

irritability. As with annoyance, efforts must be made to reduce spacecraft

noise levels which may affect, even indirectly,the performanceof some crewmembers.

Recommendations

Preliminary recommendationsfor Space Station acoustical noise limits are

based in part on JSC Design and ProceduralStandard 145, "AcousticNoise Criteria." The varied operationsand habitabilitymodules that will compromise

the Space Station were consideredin these recommendations.

Maximum allowable sound pressure levels at an individual'sunprotectedear

during relativelyshort-durationexposures (e.g., launch) are defined in the

accompanying figure. No single octave band may exceed the contour for the

time period cited.

The maximum allowable continuous sound pressure levels produced by normal

operatingequipmenton systems within work and sleep areas should be as follows: (1) Crew sleep compartmentnoise should be limited to 50 dBA; and (2)

Crew work compartmentnoise should be limitedto 60 dBA.

To avoid potentiallyannoying (continuous)sounds or disruptive(intermittent)

sounds, the maximum sound pressure level of any narrow band componentshould

be at least 10 decibels less than the sound pressure level of the octave band

which containsthe component.

Ear plugs, muffs, or other personallyworn hearing protectiondevices should

not be used as a means of achievingacceptableexposure limits except in the

case of high intensity,short durationexposuressuch as launch.

A vigorouseffort should be made to develop acousticnoise criteriaduring the

early design stage of the Space Station, and to ensure that the criteriaare

met during the developmentstage. Routine on-orbit monitoring of acoustic

noise will verify that crewmembersare not being exposed to hazardouslevels.

45
FOOD SUPPLY AND SERVICE

The food supply and service system incorporates food storage,

preparation, and dining facilities. Fresh and frozen food and

snack items provide a variety and insure continuing acceptability.

System design provides particular attention to human factors

and incorporates congregate feeding capability.
FOOD SUPPLYAND SERVICE

Richard L. Sauer and Malcolm C. Smith

Introduction

The Space Station food supply and service system will entail a major development effort. Food technology developed for previously manned space flights

was designed for relativelysmall crews on flights of limited duration. Much

of this technologyis inappropriatefor Space Station applicationbecause the

human aspects of the habitabilityand the food system effects on the general

well-being of the users received minimal consideration. The developmentand

provisioningof a Space Station system will require a new and comprehensive

effort which considersthe biological,operational,and engineeringrequirements listed in table 1.

Discussion

Historically,food system weight and volume have been prime drivers in the

design of space flight food systems. This has resulted in the compromiseof

certain palatableaspects of the food system and limited the availabilityof

foods to primarily precooked intermediatemoisture or reduced water content

and dehydratedfoods. While previous food systems have provided the minimum

daily nutrientrequirements,the form in which the food has been presentedhas

been more in the nature of a "camp out" or of combat rations. This can

severely affect the psychological acceptability of the food system for

extendedmissions.

The nature of space flight to now has also limited the types of food storage,

preparation,and productionequipmentavailable. This has resultedin a limited availabilityof fresh foods and no capabilityfor providinginflightprepared foods. Hence, it has not been possibleto provideastronautswith familiar types and varietiesof foods.

The Skylabmissions are a partial exceptionto the characteristicsdiscussed.

The nature of these missions did permit the availabilityof a limited amount

of frozen items and some human engineeringof the dining facility. These factors contributedsignificantlyto the acceptabilityof the Skylab food system. Of particulardelight to the Skylab crews was the availabilityof ice

cream and frozen precookedsteaks.

The projectedmultimission,permanentSpace Station inhabitedby up to 16 persons for long periods of time offers a challengingbut unique opportunityin

food system design. The long-termfunctionallife of the station and its subsystems will require the inclusionof food storage, production,preparation,

and serviceequipmentnot previouslyconsideredcost-effectivein manned space

flight. The new hardware and procedure possibilitiesinclude the items and

equipment listed in table 2. A definitionof how the equipmentmight appear

is shown in the sketch introducingthis chapter.

47
TABLE 1 - SPACE STATIONFOOD SYSTEMREQUIREMENTS

Biological Operational Engineering

Safety Vehic1e interface Weight

Nutrition StabiIity Volume

Sensory qualities Packaging Water for rehydration

Personalhygiene Storage Pressure

Ingestion Preparation Temperature

Digestion Servicing Relative humidity

Absorption HabitabiIity Acceleration

Gastroenterology Maintenance Vibration

Crew idiosyncracies Schedules

Nutritionalmonitoring Crew Time

Sanitation Cost

Human factors Schedules

TABLE 2 - SPACE STATION FOOD SYSTEM HARDWARE

Freezer:-IO°F includingicemaker

Refrigerators: 40°F

Ovens (convection,microwave,and radiant)

Dishwasher

Food preparationand servicingequipment: trays, tables,mixers, etc.

Capabilityfor culture and harvest of fresh salad greens

Trash management/trashcompactor

Hot water supply: 180°F

Cold water supply: 35°F

Capabilityfor baking bread items

Bulk beveragedispenser

Ice cream maker/freezer

Accessories(disposableand recyclable)

48
Recommendations

The design and operationof the Space Station food system will be criticalto

the physiologicaland psychologicalwell-beingof the Space Station crews. To

this end, the food system must meet the nutritionalrequirementsof the crewmembers and also provide for the recreationaland human acceptabilityaspects

of food preparationand dining.

In order to meet the overall objectives of the food system, the following

goals should be adopted:

1. To develop, test, and provide food service procedures which meet

overall mission objectives.

2. To ensure crew safetytogetherwith effectiveand productiveperformance of the food servicesystem.

3. To assure that applicable human engineeringprinciples are incorporated into the design and functionof the system.

4. To develop a food service operatingposture which is cost effective

in launch weight, launch volume, operating efficiency, and inflight

maintenance.

To achieve these goals, the Space Station food developmentobjectivesare the

following:

1. To manage the technology base so that required system availability

matures consistentlywith the Space Station schedule.

2. To provide a capability from the technology base to select system

options compatiblewith the planned Space Station growth stages.

3. To conduct the researchand developmentnecessaryto effecta maximal

operatingcapabilityto satisfy crew and mission needs.

49
CLOTHING AND FURNISHINGS

A typical private accommodation for a Space Station crewmember

will provide a sleep-restraint for the individual's comfort and

security, and stowage for clothing and personal items.
CLOTHINGAND FURNISHINGS

Maynard C. Dalton and John B. Charles

Introduction

The continuedmotivationof Space Station personnelover their tours of duty

will require careful attentionto the "little things", the backgroundaspects

of everyday living. Their work and off-dutyenvironmentsshould be pleasant,

and with enough variabilityto remain interesting. Especially amenable to

these considerationsare the areas of clothingand furnishings. An unimaginative wardrobe and spartan living conditionswere cited by the Skylab astronauts as factors requiringmore attention for long stays in space. Through

careful design and planning,these aspects of the crewmembers'personalenvironments can play a large part in the maintenanceof each crew's productivity

and efficiency.

Discussion

Clothing

It is anticipatedthat standard flight clothingwill be suppliedto the crewmembers for the exclusive use of each person (see table I). The apparel

should providethe appropriatethermal environmentfor the wearer, considering

the inefficienciesin air conditioningand physiologicaltemperatureregulation to be expected in microgravity. A choice of colors and styles, including

leisure and sportswear,would provide visual variety and personalexpression.

The clothing shouldalso have many pockets,to minimizethe nuisanceof having

the numeroussmall items a person carriesescaping in weightlessness.

A multigarmentsystem consistingof a shirt, trousers,and a jacket would give

the crewmembersflexibilityin achievingthermal comfort as well as providing

a large range of sizes and style options. Considerationshould be given to

the wide variationsin body size and habitus to be expected in the population

of Space Station crewmembers. Common clothing articles will be utilized for

both male and female crewmembersto the greatestpossible extent. But, these

should be adjustableto provide for a good fit and to accommodatethe changes

in body measurementsthat occur in weightlessness. Furthermore,all clothing

should be aestheticallypleasing,allow unrestrictedmobility, and allow the

efficientuse of the waste managementsystems.

Wearing comfort with adequate body protection should be emphasized in the

design and materials selectionfor the clothing. Cotton, with its comfort,

absorbancy,and wearability,is the preferredmaterial. Operationalconsiderations will require some sort of chemical treatmentfor flame proofing,which

should not affect its comfort or its cleanabilityin the onboard launderingor

dry-cleaningfacilities.

In additionto the standardizedclothing to be provided, provisionshould be

made for some personal clothing items. These items could be supplied by the

crewmember,as long as they meet the establishedcompatabilityrequirements.

Footwearwill be an importantfactor on the Space Station. It will provide

protectionfrom injuriescaused by the unusual forms of locomotionlikely to

51
Table I - STANDARDCLOTHINGSUPPLIES

Shirts

Trousers

Underwearitems

Sleep/exerciseshirtsand shorts

Socks

Slipper socks

Light-weightfootwear

Jacket

Gloves

Handkerchiefs

These items would be provided in sufficient quantities to ensure that each

crewmemberwould always have clean clothingavailable.

Table 2 - FURNISHINGSAPPROPRIATETO A MICROGRAVITYLIVING ENVIRONMENT

Bed -- Hammock or netting,with beddingmaterials

Tables and Workbenches-- Elevatedwork surfacesinclinedtoward user,

Restraintsfor equipment,loose papers

Plenty of drawers and storage compartments

RestraintSystems -- Hand holds

Foot restraints

Waist harnesses

Lockersand Drawers

Draperiesand Wall Hangings-- Aestheticallypleasing,sound absorbing

Comfort Fixtures-- Designed to ease the discomfort of physiologicaladjustments to weightlessness,such as lower back pain

Personal Items -- Pictures,sculptures

Other Items -- Yet to be defined

52
be used in weightlessness. It will be an importantcomfort factor, since the

redistributionof blood volume inflightmay leave some individualswith cold

feet. The footwearmust also incorporatea versatilerestraintsystem, since

the legs and feet will be used primarilyfor fixing the individualat a work

site. The shoe-soletrianglesand cleats used on Skylab are a possibility,as

are the use of velcro and foot-loopson the floor at commonly-usedwork stations. Underwearcan be standard,commerciallyavailableitems to suit individual tastes, subject to the appropriateoperationalsafetyconsiderations.

Furnishings

The furnishingsin the Space Stationwill necessarilybe quite differentfrom

those in use on Earth. In table 2, for example,chairs and sofas will not be

needed for relaxation. An appropriatesubstitutemight be simply a means of

mooring the person in the desired area, and allowing nearly complete relaxation in "mid-air".

Beds may be hammock-like in that they merely restrain the sleepers from floating freely about their quarters, and should incorporate provisions to hold

bedding, blankets, and pillows around the users. They might be fastened to a

wall at night, and either left in place, as shown in the figure, or stowed in

a locker when not in use.

Work stations and dining areas will also need to be designed for the wide

range of body sizes among the Space Station population, and for the pecularities of working in weightlessness. A system of foot restraints and waist harnesses might prove useful for fixing the individual at a work site. Jobs

requiring some mobility around that site could use a waist-restraint system

which slides along a fixed bar. It is anticipated that some of these

restraint devices will be permanently mounted at heavy-use locations, some

will be moveable as necessary, and some will be incorporated into the clothing

and footwear of the crewmembers.

Instrument consoles, work benches, and tables must be designed to accommodate

the "microgravity slump", the posture that the body assumes in the apparent

absence of gravity. Chairs and stools will not be required. Work surfaces

should be elevated and inclined toward the worker, who will not have the usual

assistance of gravity in bending over a horizontal surface. Several forms of

restraint to hold equipment, papers, and tools must be Frovided, and storage

compartments for loose items will be located near the place of maximumusage.

Recommendations

Careful planning can eliminate design shortcomingswhich will blossom into

major annoyances and aggravations under the potentially stressful circumstances of long stays in orbit. The analysis of similar situations in the

Skylab and Salyut orbital stations,and the testing of habitabilityand housekeeping features in short-term Space Shuttle flights, will provide a data

base from which to work. It should also be recognizedat the outset that,

inevitably,some proposedsolutionswill be found to be less than optimal in

use. Accordingly,provisionsshould be made for a degree of on-orbitmodificationof work and rest areas, as practicalexperiencereveals more appropriate solutions.

53
mm°oIIUlI[[[ o o

EDUCATIONAL IMPLICATIONS

World-wide participation in education of and by Space Station personnel.
EDUCATIONALIMPLICATIONS

John Harris

Introduction

To adequately discuss the educational implications of a Space Station, it is

necessary to first define the meaning of education in this particular context. We are looking at the way inhabitants of a Space Station can enhance

learning on Earth and provide new concepts in the sciences, especially astronomy, life sciences, and social sciences. Obviously, at this point, we cannot

enumerate specific subjects that could be taught or even classroom situations. What is needed first is an education of the public, through available

methods, to gain long-term support for a Space Station as well as development

of new concepts regarding working and living that will carry forward into the

now traditional educational systems to help prepare future citizens for a

rapidly changing life in the 21st century. As this process is occurring,

specialized groups will begin to utilize Space Station as a valuable resource

and formal learning situations can take place. These could include university

courses, public service broadcasts, and science for laymen.

Discussion

The mass media, especially television, can bring the events that occur in a

Space Station to Earth on a daily basis via newscasts. This is the first and

highly necessary step in educating the general public about the many advantages of a permanent human presence in space. Through this medium, public

interest will be piqued and people will learn what it is like to live and work

hundreds of miles above the Earth, how Space Station inhabitants react to

their environment, what type of work is being done and how this will eventually affect life on this planet. Once public interest is triggered, it will

hopefully manifest itself into continued support of Space Station, a necessary

commodity in a democracy. In addition, a realization will develop that in a

changing world a great deal of knowledge can be gained through interaction

with the Space Station population. As a result of the scientific studies on

Space Station, investigators will gain knowledge in many areas of science that

can be shared with other scientists throughout the world. Also, inhabitants

of Space Station will probably develop a more global perspective of the world

than their earthbound peers which could lead to, among other things, new

thinking in the areas of geopolitics and sociology.

NASAcan also educate the public through literature, displays, speakers, and

films devoted to various aspects of Space Station. Emphasis should be placed

on the potential of Space Station to enhance learning at all levels and to

become a forum for the exchange of scientific information on a global scale.

As interest increases, a special Space Station Office can be created to

arrange and structure interactions of specific groups with those aboard Space

Station. While at the same time, it could be used as a clearing house for all

information originating from Space Station.

Mass media has been capable of rapidly building up interest in a news event.

Their tendency for the spectacular encourages the editors to choose the dire

55
event for coverage on the front page. Press reporting of Skylab was heavy

during launch, recovery, and during the EVA repair of the laboratory. During

the long Skylab IV (84 days), coverage was relegated to the inside stories of

the newspapers and commentators tended to barely mentioned it in TV newscasts. Most of the public forgot that crewmen were orbiting overhead. Space

Station will suffer a similar fate unless its communications are not limited

to the commercial press but are expanded into the educational system generally, From this the public will realize that it is their Space Station, and

that besides industrial processes, it is a worthwhile source of information

for the United States student body from grammer school through college into

adult postgraduate education.

When the public is aware of the many possibilities for increased knowledge as

a result of Space Station, then specialized groups will begin to utilize it as

a resource and many different types of learning situations will be developed.

For instance, world leaders in the sciences and social sciences will be able

to hold discussions with their peers who are working aboard Space Station.

Earthbound coinvestigators can discuss an experiment with the principal investigator aboard Space Station. Other scientists in the same field could also

participate in the discussion. On the other hand, an investigator could make

a formal presentation of his/her work to the scientific community directly

from the Space Station laboratory. Students at all levels can join an investigator for a discussion or demonstration of the type of work in which he/she

is engaged. For example, students could interact with an expert in bioprocessing who is separating cells by electrophoresis in order to use them to manufacture pharmaceuticals. They could also question someone who specializes in

physiology and the changes that occur in the body as a result of weightlessness. On a more selective basis, outstanding students in a given subject area

could be chosen to participate in a one-on-one learning experience with a

Space Station investigator.

Recommendati ons

In order to have continued public support and eventual use of Space Station as

an educational resource, it is important to inform the public now of its

potential to expand our knowledge in many diverse areas. Prior to the actual

construction of the Space Station, NASAcan mobilize its resources to keep the

world informed as to the importance of this effort. During and after the

building phase, NASAshould keep the public abreast of Space Station activities through regular announcements and conferences with the news media as well

as publications, films, and speakers. PAOshould expand its emphasis from the

news media into the educational system in general.

A Space Station information office should be created to handle all information

originating from the Station. As operations mature, the office can keep the

public informed regarding Space Station activities as well as coordinating and

structuring learning situations between earthbound investigators and students

with those aboard Space Station.

56
CONCLUDINGRERARKS

The goals of this technicalmemorandumhave been several. It has acted as a

platform for individualNASA life scientiststo express viewpoints and consider what has been done in the past in relationshipto a Space Station. It

has focused attentionon the unique needs of a Space Station and encourages

the developmentof new ideas. In addition,by using the technicalmemorandum

as a forum, it records today's ideas in a manner which can be used by those

who follow. It will be used to communicatewith managementas well as with

interested scientists, educators, aerospace contractors, and fellow NASA

workers the perspectivesand ideas of the Life SciencesSpace Station Working

Group during its deliberationsduring late 1983 and early 1984.

It is planned to publisha secondtechnicalmemorandumin late 1984 to further

present conceptsthat are just now being developed.

57

APPENDIXA

WORKINGGROUPMEMBERSHIP

YEARS SIGNIFICANT NASAEXPERIENCE/

NAME DEGREE(S1 NASA ACCOMPLISHMENTS

M. W. Bungo M.D. 3 Cardiovascular Section, Medical

Resarch Branch and consultant

for Medical Operations Branch;

CV Physiologic Research RTOP

Manager; Mission Control Center

Flight Surgeon for Shuttle OFT

Series; design, implememtation,

and evaluation of cardiovascular

deconditioning countermeasures

in Shuttle flight program; Board

certified in Internal Medicine

and Cardiovascular Disease.

J. B. Charles Ph.D. 1 Physiologist; research into cardiovascular effects of weightlessness deconditioning countermeasures.

M. E. Coleman Ph.D. 3 Toxicologist, responsible for

evaluation of toxicity of contaminants in spacecraft atmospheres; evaluation of toxic

hazards in spacecraft payloads;

and development of concentration

limits for spacecraft atmospheric contaminants.

G. R. Coulter, Ph.D. 2 Director, Aerospace Medical

Lt Col, USAF Division Space Biotechnology

Programs Office (JSC); Clinical

Research Associate, JSC Biomedical Branch; Associate Professor

of Biology USAFAcademy.

M. C. Dalton B.S. 20 Space Station design; crew station research and development;

habitability research Skylab;

crew station design; orbiter

habitability design-SOC.

59
YEARS SIGNIFICANT NASAEXPERIENCE/

NAME DEGREE(S) NASA ACCOMPLISHMENTS

J. C. Degioanni M.S., M.D., 7 Board certified Aerospace MediPh.D. cine (Preventive Medicine),

Emergency Medicine Specialist;

Ph.D., Astronomy; M.S. Public

Health; JSC Medical Standards

Officer, 1976-79 defined medical

standards for astronaut selection Class I, II, III; designed

protocol for medical selection

of astronauts; designed SOMS;

author Shuttle medical checklist; STS-I deputy crew surgeon;

principal investigator in motion

sickness drug studies (JSC).

W. J. Frome D.D.S. 17 Provides all astronaut dental

care; developed provisions for

inflight care--Apollo, Skylab,

ASTP, STS Dental Resarch Skylab;

developed dental selection

standards; member of Space Medicine Board.

L. Gardner M.S., Ph.D. 1 Aerospace Clinical Neuropsychologist, Universities Space

Research Association, Division

of Space Biomedicine, NASASpace

Biomedical Institute; space

adaptation syndrome research and

countermeasure training; operational applications of biobehavioral medicine; Space Station

planning.

H. R. Greider B.S. 19 Wrote Mercury environmental

requirements; originated the

conceptual design for Mercury

ECS and space suit; lunar surface equipment handling problems; environmental planning for

Space Station.

J. W. Harris B.S. 20 Established radiation and meteoroid environment standards for

Apollo; editor, 1969 lunar science working group; manager,

Lunar Sample Office; member

lunar sample curatorial staff;

radiation biology; Space Biomedical Institute.

6O
YEARS SIGNIFICANTNASA EXPERIENCE/

NAM____EE DEGREEIS) NASA ACCOMPLISHMENTS

P. C. Johnson M.D. 4 Specializedmedical operational

testing pre- and postflightGemini, Apollo; P.I. for Skylab,

SL-1; MCC surgeon, STS medical

reports; Space Adaptation Research Branch Chief.

J. S. Logan M.D. 2 Chief, Flight Medicine;Mission

Operations Control Center, STS3,7,9; Deputy Crew Surgeon,

STS-5,11;Crew Surgeon,STS-6,8,

12; board certifiedin Aerospace

Medicine.

J. A. Mason M.S., M.S, 20 Hqs. NASA-planningadvancedmanned missions; JSC-Deputy Chief,

Preventive Medicine DivisionLunar Quarantine;Chief, Bioscience Payloads Office-Spacelab

life science simulation;Medical

Research Branch-Space Station

planning.

B. J. Mieszkuc M.S. 15 Virologist-Mgr.VirologyLaboratory-Lunar Quarantine, Apollo

and Spacelab flight support;

Mgr. Bioprocessing LaboratoryElectrophoresisequipment verification tests; Biomedical LaboratoriesBranch - manage clinical medicine support;Space Station planning.

M. A. Reynolds Ph.D. 14 ContaminationControlOfficer of

the Lunar Receiving Laboratory;

Curator in charge of pristine

laboratoryand cleaning requirement for lunar samples; member

of EEVT team-electrophoresis;

manager of Neurophysiological

Laboratory.

R. L. Sauer M.S. 16 ProjectManager for ShuttleFood

and Orbiter Medical System;

Manager for Advanced Life Support Systems RTOP; Project Engineer for Skylab Water, Personal

Hygiene, and Waste Management

System; licensed professional

engineer.

61
YEARS SIGNIFICANT NASAEXPERIENCE/

NAME DEGREE(S1 NASA ACCOMPLISHMENTS

C. G. Smith M.S. 22 Physiologist; human ecologist;

remote sensing studies of Earth

environment; Associate Fellow,

Aerospace Medical Association;

aerospace technology for the

disabled; member, Air Transport

Committee of the Aerospace Medical Association; member, Foundation for Science and the Handicaped; air travel for the disabled.

M. C. Smith D.V.M., M.S. 16 Subsystem Manager for Apollo

Food and Personal Hygiene

(1967-70); Subsystem Manager for

Skylab Food (1970-71); Chief,

Food and Nutrition Branch

(1970-75).

N. Timacheff M.A. Ii Chief Interpreter and staff of

Apollo Soyuz Test Project; Space

and Life Sciences interpreter/

translator joint working group

meetings since 1977; study of

Soviet aerospace achievements in

life sciences.

J. M. Waligora M.S. 20 EVA and environmental requirements on Gemini through Shuttle;

EVA liquid cooling systems;

development and testing of procedures to prevent altitude

decompression sickness; EVA

monitoring and measurement of

metabolic rate.

62
APPENDIXB

SOVIETSPACESTATIONS

Nicholas Timacheff

In 1971, the Soviet Union launched their first space station "Salyut-l".

Since then, they have been aggressively pursuing the concept of permanent

presence in space. To date, this presence has been manifested by having a

space station in orbit, although there have been periods of from a few weeks

to eight to nine months when these stations were not manned. Salyuts I

through 5 were mainly test articles, although some activities, primarily in

the systems testing, were carried out in each station. For example, in 1975

during the Apollo-Soyuz Test Project, the crew of Salyut-4, in orbit at that

time, was in frequent communication with Leonov and Kubasov during their

flight with Apollo.

Salyuts 1 to 5 were first-generation stations with only one docking port. The

atmosphere in these stations, just as in Salyut 6, 7, and all of the Soyuz

spacecraft, was always maintained at 14.7 atm + 10%, with an "Earth-like" gas

mixture, which the Soviets always emphasize. -

With launch of Salyut-7 in 1977, the USSRengaged in operating their second

generation space station. With the exception of an additional docking port

(at the instrument module, or aft) and several changes in the interior architecture, the configuration of the station remained the same. It has essentially a l-g orientation and is of tubular design: 15m long and 4m in diameter

in its widest section, the workshop area. The total habitable volume of the

station is approximately 102m3, including the docked Soyuz spacecraft. However, this volume is greatly decreased by equipment of various types which has

allowed the Soviet cosmonauts to perform a very large number of experiments

such as materials processing, Earth observation, astrophysics, geodetic surveys, and medical experiments.

In some respects, the space station design leaves much to be desired. For

example, ventilation is provided from the Soyuz spacecraft docked at the

instrument module. The air first attacks the personal hygiene and toilet

areas, then the drinking water tanks and food items storage. This has allegedly caused the finding, in the cosmonaut's oral and nasal cavities mucosa, of

an "inordinate" (sic) amount of Enterococcus bacilli and Streptococcus faecalis.

The Soviet manned expeditions in space exceeded that of Skylab on six occasions: Salyut-6 -- 96, 140, and 185 days; Salyut-7 -- 211 and 115 days.

During the periods when they were manned by the "permanent" crews made up of

two cosmonauts, the stations Salyut 6 and 7 were visited by 20 separate crews:

16 of them with two people and four with three people. Additionally, there

were 18 dockings of unmanned spacecraft (automatic transports "Progress" and

Soyuz-T) which replenished the station with all consumables, both for the crew

and for the space station operations.

63
Sleeping Bags

EVA Hatch

Waste Disposal Airlock

Personal

Hygiene

Equipment

Toilet &

Waste Disposal

Ventilator

EVA Suits

Environmental

Control System

Small Tank

w/Drinking

Water

Treadmill

Bicycle Ergometer

Trash Drinking Water

Container

Food Items

Stowage

"SALYUT-6" SPACE STATION

Showing some of the principal life support system items on board.
One of the visiting crews on Salyut-7 was a woman cosmonaut, Svetlana Savotskaya. Her experience was vastly different from her predecessor, Valentina

Tereshkova. According to the Soviets, she withstood the rigors of adaptation

and readaptation as well as or better than her fellow crewmembers. In a

departure from their traditional attitude, the Soviet designers even made provisions for private women's personal hygiene areas, not only on the SalyutT,

but on the Soyuz spacecraft as well.

The Salyut 6 and 7 stations carry two EVA suits onboard; however, in spite of

the long duration stays of the prime crews, only five EVA's have been performed, of which two were for unscheduled, emergency purposes. The other

three were for scheduled scientific operations. The most recent EVA from the

Salyut-7 lasted 2 hrs 33 min in spite of the fact that the EVA suits are rated

for a maximumof two hours activity in open space. The Soviet EVA suits are

pressurized at 5.2 to 5.8 PSl, with an emergency capability of 3.8 to 4.1

PSI. Prebreathing is done for a period of 25 to 30 minutes of 90%02, at 10.6

PSI.

The work/rest schedule is based on Moscow time to avoid "jet lag" and simplify

work for ground personnel.

In June of 1983, the Soviets launched the "Kosmos-1443", an unmannedtransport

craft, which docked with the Salyut-7. This multipurpose spacecraft (of which

we have no picture, or sketch, as yet) has a different configuration from the

Salyut or Soyuz. It has a mass of 20 m/tons, is over 13 meters in length, and

4 meters in diameter, and has an inside volume of 50 m3, which doubles the

previous work/habitability area for space crews. With the Kosmos-1443, which

has 40 m2 of solar panels, the power capability of the complex has been

increased to 7 kw. Kosmos 1443 can take up to 3 metric/tons of cargo to the

Salyut (2.5 times that of "Progress"). It also has a return module which can

take down a maximum 500 kgs of any type cargo. On its first turn-around, it

returned 350 kgs of various items, i.e., results of scientific experiments,

materials processing, and equipment to be repaired.

65
TABLE I - LIFE SCIENCEEQUIPMENTONBOARDTHE SALYUT-6AND 7 STATIONS

Portable EKG, Microcomputer for downlink telemetry of a 12-1ead EKG, vectorcardiogram, echocardiogram (also a Doppler Echocardiograph, supplied and flown

by a French cosmonaut, Jean-Loup Chretien), rheocardiogram, phlebogram,

plethysmogram, pneumogram, calf volume and separate muscle group measurements. Chibis suit (portable Lower Body Negative Pressure), penguin suit (for

stress on legs and lower back muscles), body mass measurement unit, bicycle

ergometer, treadmill with bungees (50 kgs), individual dosimeters, two radiometers (12.5 mrad sensitivity). A shower stall is available on-board, used

every two to three weeks. The taking of the shower is always announced in

connection with other health maintenance activity. Otherwise, washing and

brushing of teeth is done with a cloth soaked in an antiseptic solution.

66
"ANTIMOTION SICKNESS DEVICE"

Headcap With Restrain Straps

©

"SALYUT-7" SPACE STATION

Essentially the same as "Salyut-6". Three crewmembers are

shown to give an approximate idea of inside proportions.

Permanent crew usually consists of two cosmonauts.
Return module

"KOSMOS-1443*

Automatic cargo transport, doubling the capacity of the

"Salyut* Space Station. Also has a remote controlled return

module allowing the return to earth of processed materials,

completed experiments, etc.
APPENDIXC

PHYSIOLOGICALLYACCEPTABLESPACE STATIONAND PRESSURESUIT PRESSURES

James M. Waligora

The choice of a cabin atmospherepressurefor Space Station is influencedby a

number of considerations. Several of these factors are relatedto human physiology. In light of an increasedemphasis on extravehicularactivity (EVA),

and consideringthe resultsof our recent tests at JSC on decompressionsickness prevention,it may be useful to restate the requirementsfor acceptable

cabin and suit pressurecombinations.

Oxygen Pressure: The nominal 02 pressure in the cabin should be normoxic,

that Is, it should provide 02 pressure normally available to the alveoli of

the lungs.

Because of a dilutioneffect of water vapor and CO2 in the lungs, the higher

the 02 concentration,the higher the ambient 02 pressuremust be to provide a

normoxic level. At 3.7 psi (100% 02), 3.7 psi is the normoxic 02 pressure.

At 14.7 psi (20%02), 3.1 psi is the normoxic02 pressure.

The band width of 02 controllersand 02 sensorswill be within physiologically

acceptable variation in 02 pressure. Contingency02 pressure in the worst

case should not provide less 02 in the alveoli than availableat an 8,000 ft

equivalentaltitude.

Pressure Change Ratios: A simple predictorof the thresholdof decompression

sicknessincidenceis the ratio of tissue nitrogen (as reflectedby ambient N2

pressure in saturationsituations)to the final reduced pressure. Our best

current estimate of a zero-prebreathethresholdfrom a 14.7 psi air saturation

environment is a reductionin pressure to no less than 8.00 psi. This pressure reduction results in an N2 ratio of 1.45. Years of exposure to these

ratios in aviation indicatesthere will be no problemswith symptoms at this

level. However, because of the specific requirementsof Space Station EVA,

long periods (up to 6 hours) of substantialphysicalactivity,the possibility

of daily exposure and the need to be able to move freely from cabin to suit

pressure,we are currentlyverifyingthat the 14.7 psi to 8.00 psi decompression can be done three days in a row with representativeEVA times and activities without problem. There will be worst cases that involve a greater decompressionthan the 1.47 nominal case as a result of worst case ranges of control bends in both th_ cabin pressureand the suit pressure. However,variations in these control ranges also will be experiencedin test verification

data, and the nominal pressuresshould be the design pressures. This does not

apply to significantlylower contingencypressuresof either the cabin or the

pressure suit which must be considered at their own nominal values. For

instance,if a 14.7 psi cabin has an 8.00 psi contingencypressuremode, the

impact of this decompressionmust be consideredin planningfor subsequentEVA

from this cabin pressure. In a like manner, a lower contingencypressurein a

pressure suit must be evaluatedin terms of duration of exposureand possible

increasedincidenceof symptoms.

69
Nitrogen Washout Procedures: Where required changes in pressure exceed the

allowable N2 ratio, prebreathing with 02 or a reduced N2 pressure atmosphere

has been used to reduce tissue N2 pressure. In assessing the effect of prebreathing, we use a half-time decay equation to estimate the reduction in tissue N2 pressure prior to decompression. Both 240 min and 360 min tissues were

used in the analysis for Shuttle. Our two current EVA preparation procedures

involve some period of prebreathe to reduce tissue N2 concentration. In our

Shuttle planning, we used certain operationally successful 02 prebreathing

procedures as benchmarks rather than an R value of 1.45. The results of our

bends tests indicate that our assumptions were not conservative enough to completely preclude decompression sickness.

Certainly for Space Station, where it might take two weeks to return a crewmember to Earth, we would want to be conservative regarding the incidence of

decompression sickness.

Our current recommendation for calculating acceptable bends prevention protocols for Space Stationwould be to use a maximum N2 ratio of 1.45 and to use

tissue half-timesof from 360 min to 720 min to account for N2 tissue loss

from prebreathe. Researchneeds to be done to establishwhich of these halftimes would be most appropriate. The Lambertson committee has recommended

that we use a 720 min half-time,and this conservativeapproachshould be used

until the use of a shorter half-timecan be verifiedas appropriateby test.

ProceduresInvolvingMultipleDecompression: Where more than one reductionin

pressure is involved,the guidelinesalready statedfor N2 ratiosand calculation of tissue N2 pressure from assigned half-timeswill not provide adequate

protection. There is empiricalevidence that where multiple decompressions

are involved,an initial decompressioninvolvinga N2 ratio of less than 1.45

can potentiatethe appearanceof symptomsduring a second decompressionat a

much later time. There is radiographicand animal indwellingDoppler data

indicatingthat bubbles of a size below that which can be heard with a precordial Doppler sensor can form after a decompressionfrom 14.7 psi to 11.5 psi.

This is an N2 ratio just in excess of one.

One theory is that micro-bubblesform or increase in size at any level of

supersaturation,but it is only when the N2 ratio exceeds some critical value

(1.45?)that bubbleswill continueto grow and cause symptoms. A corollaryof

that theory is that once micro-bubbleshave formed or increasedin size, it is

difficult to reduce them with 02 prebreathing. They act like tissue with a

very long half-timefor N2 washout.

With these considerationsin mind, supersaturationshould not be al/lowedto

occur on any but the final decompressionin a multiple decompressionexposure. That is, a N2 ratio of 1.0 should be limitingon these decompressions.

EquationsUsed in the Calculations:

1. Equationfor calculationof alveolor02

Pa 02 : FiO2 (Pb - 47) F PC02 X (FiO2 + 1 - F],02)_

L (o.85)

70
Where Pa 02 = alveolar partial pressure of oxygen

Fi 02 = oxygen fraction in breathing atmosphere

Pb = barometric pressure of the breathing mixture

0.85 = on assumed respiratory exchange ratio

PCO2 = partial pressure of CO2

PAO2 at sea level = 104 mm

PAO2 at 8000 ft = 68 mm

2. Pressure Change Ratios

RNs - TN2

Pf

Where TN2 = tissue N2 in saturated environments nominally assumed equal to

ambient N2

Pf = the pressure after the final decompression

3. Tissue N2 Calculation

PT = Po- _Pa-Po)(l-e-kt)_

PT = final tissue N2 pressure

PO = original tissue N2 pressure

PA = ambient (breathing) N2 pressure

K =

t = time of exposure to breathing gas

K = 0.693

T 1/2

Application to Space Station Pressure Suit Pressure Combinations

Figure 1 is a plot of Station pressure and minimum suit pressure consistent with free movement from one pressure to another. These conditions

are calculated to be equivalent to a 14.7 to 8.00 pressure combination and

also provide normoxic 02 levels with the indicated maximum 02 concentrations. The combinations only apply after saturation at the Space Station

pressure. To avoid bubble formation in cabin pressures of less than 11.6

psi, either several stages of decompression would have to be used or prebreathe with 02 would have to be accomplished prior to decompression to

cabin pressure.

71
Space Station Scenarios Assuming 720 minute 1/2 time

Cabin Pressure Suit Pressure Max U2% _onszralnzs

14.7 psi 8.0 psi 26 None.

11.6 psi 5.75 psi 34 Stay at 11.6 psi 72 hrs.

prior to EVA.

10.2 psi 4.8 psi 38 Prebreathe 130 min prior to

going 10.2, Stay at 10.2 psi

72 hrs prior EVA.

9,4 psi 4.3 psi 40 Prebreathe 220 min prior to

going to 9.4. Stay at 9.4

psi 72 hrs prior to EVA.

7.5 psi 4.3 psi 48 Prebreathe 460 min prior to

going to 7.5. Stay at 7.5

psi 8 hrs prior to EVA.

72
ACCEPTABLECABINANDSUIT PRESSURECOMBINATIONS

AS SAFEAS A DECOMPRESSIONFROM14.7 PSl TO 8.0 PSl

ASSUMESEQUILIBRATIONAT CABIN PRESSURE

r- PRIORTO DECOMPRESSIONTO SUIT PRESSURE f MAXIMUMO^

.__,_ CONCENTRATION

t--

t_

0 I f ! Q l i ! ! I i I I I r i

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

CABIN PRESSURE (PSIA)

FIGURE i

73

APPENDIXD - SUPPORTINGHEALTHMAINTENANCEDATA

REVIEWOF PASTMEDICALPROBLEMSENCOUNTEREDINFLIGHT (REF. NASATM 58248}

Anorexia (loss of appetite)

Space Sickness

Fatigue

Insomnia

Dehydration

Flatulence (gases in stomach or intestine)

Dermatitis (skin inflammation)

Back Pain

Upper Respiratory Infection

Conjunctival Irritation (eye irritation)

Subungual Hemorrhage (bruises under fingernails from EVAsuit gloves)

Urinary Tract Infection

Cardiac Arrhythmia (abnormal heart beat)

Headache

Muscle Strain

Diarrhea

Constipation

Barotitis (ear problems from atmospheric pressure difference)

Bends (decompression-caused limb pains)

Chemical Pneumonitis (lung inflammation)

CLASSIFICATIONOF EMERGENCYSERVICESACCORDINGTO THE

JOINT COMMISSIONONACCREDITATIONOF HOSPITALS(1984}

Level I Emergency facility offers comprehensive medical care 24 hours a day

with at least one physician experienced in emergency care. There

shall be in-house physician coverage with specialties in medicine,

surgery, orthopedics, obstetrics-gynecology, pediatrics, and anesthesiology. The hospital offers definitive care capabilities in

these specialties and other specialty consultations are available

within 30 minutes.

)

Level II Emergency facility offers comprehensive medical care 24 hours a day

with at least one physician experienced in emergency care. Specialty consultation is available within 30 minutes. In-hospital

capabilities, otherwise, are similar to the level I facility.

Level III Emergency facility is staffed by a nurse or medical technician. A

physician is available within 30 minutes. Specialty consultations

are available by request or transfer to a definitive care facility.

Level IV First aid station with the availability of personnel capable of

rendering life saving measures, then transfer to another facility.

No call roster is required.

75
SUMMARYOF HEALTH DATA COLLECTEDDURING 10 YEARSOF

POLARISSUBMARINEPATROLa---20,960MAN-YEARS

Disease/ No. Rate No. Transfer Deaths Comments

Condition Casesb per MY Cat. At Sea

Gen'l Surgery 269 0.0238 32 6 70 appendicitis;

Referral 45 pionidalabscess;

23 burns.

Bone & Joint 264 0.0126 52 1 66 lumbosacralstrain;

34 fractures;

2 amputations.

Gen'l Medical 240 0.0115 30 0 134 flu; 31mononuc;

13 viremia.

Gastro- 229 0.0109 19 6 155 gastroenteritis;

Intestinal 17 gastritis;

14 hepatitis.

Respiratory 185 0.00883 9 6 80 pneumonis;43 URI;

36 acute bronchitis;

11 pneumothorax.

Ear, Nose, and 165 0.00787 14 1 96 pharyngitis;

Throat 23 tonsilitis.

UrinaryTract 115 0.00549 19 3 39 ureteralcalculi;

26 epid; 23 pyeloneph.

Psychiatric 58 0.00277 15 3 1 25 anxiety reaction;

13 neuroticdepr.

Neurologic 53 0.00253 18 4 3 18 headache;9 concussion; 8migraine.

Dental 50 0.00239 9 1 28 periapicalabscess;

13 pericoronitis+.

Eye 48 0.00229 16 3 18 cornealabrasions

or foreignbody;

16 conjunctivitis;

5 burns.

Cardiovascular 9 0.00043 5 2 1 3 hypertension;

2 chest pain.

TOTAL 1685 0.0804 37 5

a. Compiled from data in: Tansey, W.A., J.M. Wilson, and K.E. Schaefer.1979. Analysis of

Health data from 10 years of Polaris SubmarinePatrols. Undersea BiomedicalResearch,

SubmarineSupplement,$217-$246.

b. Excludestransfer at sea and death; includesonly cases resultingin 1 or more days lost

from work.

76

1. Report No. I 2. Government Acce_sion No. 3. Recil_ent's Catalo9 No.

NASATM 5825;2 !

4. Title and Subtitle 5. Report Date

SHUT.TLEOFT MEDICALREPORT- Summaryof Medical Results from July 1983

STS-I,STS-2, STS-3, and STS-4 6. PerforminOgrganizationCo_

7. muthor_)_Editors s. PerformingOrganizatiRq: on_ort N<

SamL. Pool, M.D.; Philip C. Johnson, Jr., M.D.; and S-522 John A. Mason

10. Work Unit No.

9. Performing Organization Name and Address 199-89-00-00-72

Lyndon B. Johnson Space Center

Houston, Texas 77058 tl. Contract or Grant No.

13. Type of Reportand PeriodCover

12. Sponsoring Agency Name and Address

Technical Memorandum

NationalAeronauticsand Space Administration 14.SponsoriAgenc n<j yCx)de

Washington,D.C. 20546

15. Supplementary Notes

16. Abstract

The medical operations report for the Orbital Test Flights (STS-I, 2, 3, and 4) includes a

review of the health of the crews before, during, and immediately after the four Shuttle

orbital flights. Areas reviewed include health evaluation, health stabilization program,

medical training, medical "kit" carried in flight, tests and countermeasures for space

motion sickness, cardiovascular profile, biochemistry and endocrinology results, hematolog)

and immunology analyses, medical microbiology, food and nutrition, potable water, Shuttle

toxicology, radiological health, and cabin acoustical noise. Also included is information

on environmental effects of Shuttle launch and landing, medical information management, an_

management, planning, and implementation of the medical program.

17. Key Words (Suggestedby Author(s)

Toxicology RadiationHazards

AcousticNoise EnvironmentalEffects

Medical Science Nutrition Is. Di:tribution Stmtmment

Management, Planning Crews (Health)

Medicine Motion Sickness Unclassified - Unlimited Cardiovascular System Water

Training Simulators Hematology/Immunology Subject Category: 51

Food Microbiology

Biochemistry/Endocrinology

19. Security Qamif. (of this _port) I 20. Security Cla_if. (of this _ge) 21. No. of Pages I 22. Dice" I I

Unclassified Unclassified 102

"For Mle by _e Natio_l Techni_l Information _i_, Spri_field, Virginia 22161

_C F_m 1_4 {R_ Nw 751 - U.S. GOVERNMENTPRINTING OFFICE: 1983--669-013/3 0 6 6 NASA