Apollo Experience Report Lunar-Sample Processing in the Lunar Receiving Laboritory High-Vacuum...

8/8/2019 Apollo Experience Report Lunar-Sample Processing in the Lunar Receiving Laboritory High-Vacuum Complex

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C A L N O T E NASA TN 0 -8298

*

EXPERIENCE REPORT -IN

RECEIVING LABORATORY

R. WhiteJohnson Space Center

77058

N A L A E R O N A U T I C S A N D S PA CE A D M I N I S T R A T I O N W A S H I N G T O N , 0. C. AUGUST 1976


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1. Report No.NA S A TN D-8798

7. Author(s)

2. Gviernment Accession No. 3. Recipient's Catalog N o.

~ ~~r8.erforming Organization Report NO.

4. Title and Subtit leAPOLLO EXPERIENCE REPORTLUNAR-SAMPLE PROCESSING IN THE LUNAR RECEIVINGLABORATORY HIGH-VACUUM COMPLEX

5. Report DateAupust, 1976

6. Performing Organization CodeJSC-07272

11. Contract or Grant No.Lyndon B. Johnson Space CenterHouston, Texas 7705813. Type of Report and Period Covered

Technical Note2. Sponsoring Agency Name and Address

David R. White~9. Performing Organization Name and Address

National Aeronautics and Space AdministrationWashington, D. C . 20546

s-4599 14- 0- 2-01-7210. Work Unit No.

14. Sponsoring Agency Code

17. Key Words (Suggested by Author(s) )Sterilization OutgassingVacuum cha mbe rs AppendagesColdtr aps Ion pumpsGloves PurgingTools Hermetic seal s

I15. Supplementary Notes

18. Distribution Statement

STAR Subject Category:12 (Astronautics, General)

16. AbstractA high-vacuum complex composed of an atmosphe ric decontamination syst em , sampl e-process ingchamb ers, stor age chambe rs, and a tran sfe r syst em was built to pro cess and examine lunarmat eri al while maintaining quarantine status. Problems identified, equipment modifications, andproced ure changes made f or Apollo 11 and 12 sample processing are presented. The sample-proces sing e xperie nces indicate that only a few operating personnel are required to process thesam ple efficiently, safe ly, and rapidly in the high-vacuum complex. The high-vacuum complexwas designed to handle the many contingencies, both quarantine and scientific, associated withhandling an unknown entity such as the lunar sample. Lunar-sample handling necessitated a com-plex system that could not respond rapidly to changing scientific requirem ents a s the char act er-is t ics of the lunar sam ple wer e bette r defined. Although the complex successful ly handled theprocessing of Apollo 11 and 12 lunar sampl es, the scientific requi remen t for vacuum samp les wasdeleted after the Apollo 12 missio n just a s the vacuum syste m was reaching i ts full potential.

19. Security Classif. (of this repo rt)Unclassified Unclassified 42

20. Security Classif. (of this page) 21 . NO. of Pages 22. Price'$4.00

~~~~ ~

For sale by the Nation al Technical Infor mati on Service, Springfield, Virginia 22161


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CONTENTS

SectionSUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Design Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Quarantine Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . .Scientific Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Engineering Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . .

VACUUM SAMPLE-PROCESSING COMPLEX DESCRIPTION . . . . . . . . . .F - 2 0 1 Vacuum Glove Chamber . . . . . . . . . . . . . . . . . . . . . . . . .Vacuum Tra ns fe r Chambers . . . . . . . . . . . . . . . . . . . . . . . . . .Vacuum Storage Chambers . . . . . . . . . . . . . . . . . . . . . . . . . . .Atmospheric Decontamination System . . . . . . . . . . . . . . . . . . . . .F- 601 Ultra-High-Vacuum Chamber . . . . . . . . . . . . . . . . . . . . . .Control Console . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

DEVELOPMENT AND OPERATIONAL DIFFICULTIES . . . . . . . . . . . . .Maintenance of the Vacuum Environment . . . . . . . . . . . . . . . . . . .Arm and Glove Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . .Adaptability of Tools and Containers to Operator. Gloves. and VacuumEnvironment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Mechanisms of Tr an sf er Between Associated Vacuum Chambers . . . . . . .Sample Process ing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Development of an Effective Operational Team . . . . . . . . . . . . . . . .

POSTMISSION PROCESSING . . . . . . . . . . . . . . . . . . . . . . . . . . .CONCLUDINGREMARKS . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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FIGURES

Figure123456789

10111 213141516171819

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A schematic diagram of the LRL high-vacuum complex . . . . . . . . 6The LRL high-vacuum complex . . . . . . . . . . . . . . . . . . . . .High-vacuum- complex contro l console . . . . . . . . . . . . . . . . . 7The F-201 vacuum glove chamber . . . . . . . . . . . . . . . . . . . 8

910

The glove operator area of chamber F-201 . . . . . . . . . . . . . . .2LRL 101.3-kN/m (1 atmosphere) arm/glove system . . . . . . . . .

Apollo 11 lunar sample . . . . . . . . . . . . . . . . . . . . . . . . . 11The F-207 sam ple carousel . . . . . . . . . . . . . . . . . . . . . . . 1 2Bolt-top sample containers . . . . . . . . . . . . . . . . . . . . . . . 13Single-action sample containers . . . . . . . . . . . . . . . . . . . . 13Dolly and basket . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 4Sample container dolly . . . . . . . . . . . . . . . . . . . . . . . . . 1 4Shoulder, arm, and glove assembly . . . . . . . . . . . . . . . . . . 19Glove and w r i s t assembly . . . . . . . . . . . . . . . . . . . . . . . .Side view of glove and wrist assembly . . . . . . . . . . . . . . . . . 20Overglove sleeve and glove assembly . . . . . . . . . . . . . . . . . .

20

20ALSRC jack F-201-139 . . . . . . . . . . . . . . . . . . . . . . . . . 24

2425

ALSRC opening pliers (SEZ 36104697-301) . . . . . . . . . . . . . . .Ratchet and 0.95-centimeter (0.375 inch) drive (SK 67606-110) . . . .

20 Canholder as sembly (SDZ 36106027-301) . . . . . . . . . . . . . . . . 2521 Five-centimete r (2 inch) scoop (SEZ 36104724-301) . . . . . . . . . . 2522 Hammer (SEZ 36104728-301) . . . . . . . . . . . . . . . . . . . . . . 2523 T-handle (SEZ 36106104-301) . . . . . . . . . . . . . . . . . . . . . . 26

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Figure Page24 Tweezers (SEZ 36104416-301) 2625 Floor brus h (SEZ 36104408-302) 2726 Universal handle (SEZ 36104404-301) 2727 Radiation counting sample containers and tools 28

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APOLLO EXPER IENCE REPORTL U N A R - S A M P L E P R O C E S S I N G I N TH E L U N A R R E C E I V I N GL A BO R A TO R Y H IG H- VACUUM CO M PLEX

B y D a vi d R . W h i t eL y n d o n B . J o h n s o n Sp ace C e n t e r

S U M M A R YThe high-vacuum complex was constructed specifically for the preliminary exami-nation, i n a vacuum environment, of lunar mater ial returned by Apollo crew members.Quarantine st atu s of the lunar materia l w a s to be maintained during the examination.The high-vacuum complex w a s used fo r Apollo 11 and 12 sample processing. Initialanomalies and const raint s that resulted from receiving the lunar materia l, meeting thedesign-philosophy requi rements f o r vacuum processing, and supporting the basic func-tions of the chamber team were identified and problems were solved. These anomaliesand constrain ts included the maintenance of the vacuum environment, the constrain tsimposed by the ar m and glove assembly on the operator and chamber tools, the adapta-tion of tools and containers to the vacuum environment, the mechanism of tr ansf er be-tween associated chambers , the procedures fo r sample processing, and the development

of an effective operational chamber team. After these problems wer e solved, the vac-uum complex began to reach its full potential during postmission processing . However,no samp les we re returned f ro m the Apollo 13 mission and the scientific requirementsfo r vacuum sample process ing were deleted fo r the Apollo 14 and subsequent missions .

I NTRO DUCTI O NIn 1964, a specia l ad hoc committee of the National Academy of Sciences con-sidered the implicat ions of the Apollo flights to the Moon and the ret urn to Ear th of lu-na r sam ples for study by investiga tors throughout the world. A sys tem was needed topro ces s returned lunar samples in a controlled vacuum environment, to prevent terres-trial contamination of lunar- sample mater ials, and to prevent r el ea se of possible lunarorgani sms into the surrounding environment. For these purposes, the Lunar ReceivingLabora tory (LRL) high-vacuum complex w a s built.The high-vacuum sample-processing complex is composed of the a tmospheric de-contamination system, the transfer system, the sample-processing chambers (theF - 2 0 1 vacuum glove chamber and the F - 6 0 1 ultra-high-vacuum chamber), and thesample- and tool- sto rag e chambers (carousels). This repor t desc ribes the atmosphericdecontamination system briefly but is concerned primarily with the vacuum sys tem s


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and, in parti cular, the F- 201 vacuum glove chamber. The F- 601 ultra-high-vacuumchamber will not be discussed in this repor t because it did not support the Apollo 11 and12 missions directly. The basic operating team fo r the vacuum complex is describedin the following sections.As an aid to the reader, where necessFry the original units of mea sure have beenconverted to the equivalent value in the Systeme International d'Unitgs (SI). The SI

units ar e written first, and the or iginal units are written parenthetically thereaf ter.Design Requirements

Design requirements fo r the F- 201 high-vacuum sample-processing complex in-cluded quarantine requirements, scientific requi rement s to pre ser ve the original con-dition of the lunar sample until its release to qualified investigators, and engineeringrequirements. The engineering requirements were neces sary to accomplish the quar-antine and scientific tasks.

Quarantine RequirementsThe pr ime quarantine requ iremen t was the quarantine of the lunar ma te rial in thevacuum complex fo r a time period (approximately 60 days) during the t esti ng of select-ed portions of the mate ria l fo r substances that might be harmful to animal o r plantlife. Also, the re su lt s of these tests were important in justifying the termination ofthe 3-week quarantine of the astronauts.herently suitable f o r quarantine operations because it operates at less than atmosphericpre ssure. Consequently, any leakage would resu lt in material trans fe r into the sys temra ther than outward. However, the requi rement of testing the lunar sample f o r thepresence of biological life necessitated that the vacuum syst ems be st er il e on receip t ofthe lunar material. To be compatible with the vacuum environment and the scientific

requirements, heat steri lization was chosen as the pref err ed method fo r the vacuumsystem. Other types of steril ization, such as formaldehyde or ethylene oxide, wereundes irable because of res idue that could contaminate the sample and limit the ultimateoperating vacuum pr ess ur e. Both heat steri lizati on and per ace tic acid steril izationwer e used in the atmospheric decontamination cabinets of the complex. These cabinetsprovided biocidal ster ilizat ion fo r all ite ms entering and leaving the vacuum chambers.The exterio r surface s of sealed containers containing lunar sampl es being tran sfer redout of the vacuum chambe rs o r being returned to the vacuum chambers were steril izedby spraying the surf aces with peracetic acid in the R-102 abinet (fig. 1). After a soaktime of 30 minutes, the per ace tic acid was removed by a sterile-water spray and a dry-ing cycle was started, This procedure allowed the transf er of sample s to other con-tainment cabinets in different laboratory areas without exposing the samp le to the dam-aging high temperatu res necessa ry in heat sterilization. Additional tools o r containersthat required tra nsf er into the vacuum proce ssing chamber were heat steril ized at aminimum temper atu re of 433 K (160"C) o r 4 hours in the B-302oven.

The high-vacuum-processing complex is in-

The atmospheric decontamination cabinets (R- 02, R- 103, and R- 02)were steri-lized initially by soaking with per ace tic acid before lunar-sample receipt. Before sam-ple receipt, the int eriors of the vacuum chambers and header s were ster ili zed by main-taining a minimum surface temperatur e of 393 K (120"C) fo r 24 hours at vacuum

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F-2 0 7 sample carousel206 tool carousel Ultra-his vacuum chamber

Science observer port

camera equipment

Atmosphericdecontaminationcabinets

R-103

R-102

R-101

Vacuum glove chamber

Figure 1.- The LRL high-vacuum complex.2 -6pre ssu res between 133 and 0.133 mN/m (10-3and 10 tor r) . This temperature wasmaintained by means of exte rio r surface heaters, the rma l blankets, and thermocouples.

The se procedur es res tric ted any potentially harmful lunar o rganis ms to the vac-uum processing chamber s, eliminated migration of Earth (t er re st ri al ) organi sms intothe vacuum-chamber complex (and thereby prevented compromise of te st s to detectlunar organisms i n lunar samples ), and allowed trans fer of i tems to and from thevacuum-chamber complex.

Scientific R equireme ntsScientific require men ts for the high-vacuum processing complex included thefollowing.1. Receive the ret urned containers and remove the samples.2. Identify, catalog, and maintain complete histories of all samples.

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3. Photograph, weigh, and make microscopic examinations of the samples, s othat decisions can be made on the distribu tion of lunar mater ia l.4. Maintain a sample-process ing and sto rag e environment compatible with pre-serving the original condition of the sample.

Engineering RequirementsThe engineering requi rements were a di rec t resu lt of the constraints imposed bythe quarantine and scientific requirements . Because of the unknown quali ties associ-ated with lunar mate ria l, the original condition of the lunar sam ples had to be pre-served . Consequently, a vacuum environment w a s chosen for initial sample processing.To further pr ese rve sample condition and to provide an ultraclean vacuum environment,the mate ria ls to build the high-vacuum complex were selected carefully. The types ofmaterial s exposed to the sample had to be kept to a minimum, with emphasis on elimi-nating or reducing organic mate ria ls. In addition, the mate ria ls had to withstandsterilization temperatu res of a t lea st 393 K (120" C). The basic materials selectedwere stainless s ee1, Teflon (tetrafluoroethylene) , aluminum, Viton (fluorinated hydro-

carbon), Pyrex glass, and molydisulfide lubricant.The time dependency of c er ta in samples (biological and low-radiation samples)introduced some complexity into the vacuum-complex design. To expedite these sam-ples, the initial design included two processing c ham ber s so that the two returnedsample containers could be processed simultaneously. To reduce cos ts, the sam e en-trance cabinets and chambers were to be used for both chambers. This requirementnecessitated an elaborate transfer system to direct the two returned sample containersto their respective processing chambers. After fabrication had started on the re st ofthe complex, a reduction of funds forced deletion of the requirement fo r the secondglove processing chamber. Therefore , an unnecessary and complicated transf er s y s -tem remained in the vacuum complex. Proble ms creat ed by the trans fer syste m ar e

discussed elsewhere in this repo rt.To provide maximum flexibility i n handling and processing lunar samples, an ar m2and glove assembly w a s chosen so that an operator could work directly in a 0.133-mN/m ( l o m 6 or r ) vacuum environment. The initia l concept w a s to use an a rm andglove assembly patterned af ter the Apollo space-suit gloves. Th is assembly wouldhave required an operator to work from a man-rated chamber so that the maximum

pr es su re a cr os s the a r m and glove assembly would be 24.13 kN/m (3.5 psi). Safety2and cost cons train ts and the feas ible contractor development of a 103.4-kN/m (15 psi)maximum-pressure a r m and glove assembly eliminated thi s concept. The final designconfiguration w a s an a r m and glove assembly that enabled the ope rator to perform tasksin the high-vacuum environment while remaining in a normal atmospheric environment.

2

To meet the requirements of a clean, ste ril ize d, and controlled environment,unique constraints w ere imposed on the basic high-vacuum complex. To reduce thepossibility of backstreaming of oils, which is common in vacuum diffusion pumps, cold-trapped turbomolecular pumps wer e chosen fo r pumping in the low- and medium-vacuumrange during sys tem pumpdown. For the high-operating-vacuum range , ion pumps

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wer e chosen to maintain the high-vacuum environment in the complex. The chamberswe re isola ted by elect rical ly operated valves from the turbomolecular pump headers.An ion pump does not r equir e a forepump to pump the collected gases to atmosphericpr es su re be,cause the ionized gase s a r e trapped on the anode surface of the pump.Hence, a closed system is maintained with les s chance of outside contamination.Additional design requirements were tools that the glove operator could manipu-la te while handling the lunar sample without contaminating the sample or the environ-ment and a sys tem in which detailed photographic and microscopic studies could beconducted.

V A C U U M S A M P L E -P R O C E S S I N G C O M PL EX D E S C R I P T I O NThe components of the LRL vacuum sample-processing complex a r e the F-201vacuum glove chamber, the vacuum tra nsfer chambers (locks), the vacuum storagechambers (carouse ls), the atmospheric decontamination cabinets, the F-601 ultr a-

high-vacuum chamber, and a contro l console. The vacuum-complex layout is shownin figure 1. Figure 2 is a schematic of the complex. In figure 3, the complex controlconsole is shown in the foreground and pa rt of the vacuum complex (two storage carou-se ls and c am er a control station platform) is shown in the background.

F-201 V a c u u m G love C h a m b e rThe F-201 vacuum glove chamber (fig. 4) s the sample-processing chamber.The chamber provides the capability for handling it em s being processed using an a r mand glove assembly. In addition, provis ions ar e made for sample photography, micro-scopic examination, transfer, sample weight determinations, and gas analysis.Basic chamber operating team. - The basic operating team f or the F-201 vacuumglove chamber is composed of the following personnel, who perform the functionsnoted.1. A technician, or glove operator, performs manipulative tasks within a hard2vacuum ( 0 . 1 3 3 mN/m (and glove assembly while working unencumbered at atmospheric pr ess ure .to rr) ) by means of an articulated anthropomorphic a r m

2. An alternate glove opera tor rota tes with the glove operator in performingmanipulative tas ks i n the chamber and acts as an extr a observer f or the glove operator.3 . A scientific observer, located on the opposite side of the chamber f ro m thea r m and glove operator, observes activity from a gl ass port on the chamber top. H i sfunctions ar e to observe and provide instruction i n handling the lunar sample and tomake microscopic examination of the sample through his port .

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Figure 3 . - High-vacuum-complex contro l console.4. A caineraman, located on a platform above the chamber, controls the chamberelevato r platform fo r microscopic and photographic functions. By moving the sampleinto an optical "penthouse" above the chamber, the cam eram an may take reco rd, con-tour, and ste reoscop ic photographs of the six sides of the sample.5 . A samp le-p rocess control ler monitors chamber activity (by means of televi-sion monitors), monitors vacuum instrumentation, provides control for t ran sfer in thevacuum complex, advises the scientific observer, and provides instruction to the gloveope rato r on the implementation of tools, containers, and procedures .Glove chamber description. - The F-201 vacuum glove chamber has an approxi-mately pentagonal form, four s id es of which a r e connected to othe r vacuum chambers.The F-201 chamber is approximately 74 centimeters (29 nches) high, 147 centimeters(58 nches) wide, and 140 centimeters (55 inches) deep, and the chamber is constructedof 300-series stainless steel. The glove operato r ar ea of chamber F-201without theinstallation of the glove asse mbl ies o r operator optical port is shown in figure 5.

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Figure 5. - The glove opera tor ar ea of chamber F-201.The weighing sy st em in the F-201 glove chamber is used to weigh it em s rangingfrom 0 to 10 kilogr ams. The load cell system is located in the top left sid e of the F -201

glove chamber (fig. 4). A l l sur fac es exposed to a vacuum ar e constructed of sta inl esssteel. The weighing sys tem consists of a multirange for ce tra nsduc er, a readout in-strume nt, and assoc iated controls.The ca me ra operato r us es the camera-control station to position the lunar -samp le

elevator for photographing side v i e w s of the lunar sample. The control station platformabove the F-201 chamber (the background of f ig . 3) con sis ts of c am er as , light projec-tor s, and elevator controls. Figure 7 is a photograph of an Apollo 11 lunar sampletaken with this system.

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The F-203 tr ansf er chamber is 30.48 cen timeter s (12 inches) in diameter by53.34 centimeters (21 inches) in length. Thi s chamber is a stainless-steel cylindercontaining a 200-l iter/sec ion pump, a pumping port , and 30.48-centimeter (12 inch)isolation valves. The chamber per mit s the tr an sf er of it em s between the F-201 glovechamber and the F-207 carousel (fig. 8) without alter ing the working pr es su re of eithervessel. Also, the F-203 chamber allows sample carousel replacement by isolation andsterilization.

Vacuum Storage ChambersThe storage system for the F-201

vacuum glove chamber consi sts of themobile F-207 sample carousel (fig. 8) andthe F-206 tool carousel. The F-207 sam-ple carousel is attached to the F-201chamber by means of the F-203 transferlock. The sample carousel is composed ofa 91.44-centimeter (36 inch) high, 101.6-centimeter (40 nch) diameter stainless-steel tank, a 200-l iter/sec ion pump, anadjustable-height dolly base, an elevator-drive subassembly, and a spider subassem-bly.

The dolly base rol ls on four ca st er sand is equipped with a handwheel that oper -ate s four screwjacks to ra is e or lower thecarousel tank in fitting the ca rousel t o the

View port4- - otary dr iveK-Elevator dri ve (rack 1Vacuum gat e va lveExtensor- -203 transfer lock

F-201 port

-Elevat ing system (chamb er1

Figure 8. - The F-207 sample carousel.

F-203 chamber. The ion pump mainta ins a vacuum inside the carousel when it is de-tached from the re st of the vacuum complex. This sys tem allows the removal of acarousel when its storage capacity is exceeded and the attachment of an empty car ouselto the complex.

Sample containers (figs. 9 and 10) and dollies (figs. 11 and 12) are stored on thespider subassembly and positioned by the elevator -drive subassembly. The carouselspider subassembly cons ists of two tiers of 1 2 monorails each. The monorails radiatefr om the spider main shaft and ar e used as storage ra cks fo r sample dollies. To fa-cilitate sample transfer, the desired tier is positioned verti cally f or alinement to thechamber entrance and then rotated to the desired monorail position. The 2 4 monorailpositions are selected and controlled electr ically f ro m the complex control consolethrough the elevator-drive assembly.The F-206 carousel se rv es as a tool-storage caro usel while maintaining the tools

in the 0.133-mN/mF-201 glove chamber. The tool carou sel is sim il ar to the sample carousel except thatthe tool carousel is not movable and is attached to the F-201 glove chamber vacuumheader.

2 torr) pressur e range. The tool carousel is attached to the

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Figure 9. - Bolt-top sample con tainer s.

Figure 10. - Single-action sample con tainer s.At mospheri Decon amina t io n Sys e m

The atm osph eri c decontamination system (fig. l) , which cons is ts of five atmos-pheric cabinets, is used to decontaminate it ems biologically that are enter ing and leav-ing the vacuum complex. The sys tem function is described in the secti on entitled'vQuarantine Requirements. *'Although this report is not concerned direc tly with quar-antine prob lem s associat ed with the retur ned lunar sam ples, a brief description isgiven of this sys tem.

Items enteri ng o r leaving the complex vacuum c ham ber s may p as s through one oftwo decontamination branches. The heat-sterilization branch, consis ting of the B-302oven and the R-302 a tmos pheric handling cabinet, te rmi na tes at the F-302 vacuumtr an sf er cham ber. The peracetic-acid-sterilization branch (consisting of the R- 101ai rlock cabinet, the R- 102 sterilization cabinet, and the R- 103 drying cabinet) te rmi-nates at the F-123 vacuum tra ns fe r chamb er.

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All the cabinets contain a nitrogenenvironment at slightly l es s than atmos-pheric pre ssu re. The specific functionsfor each cabinet are as follows.1. R-101: Acts as an airlock andprovides nitrogen purge2. R-102: Provid es surface st er i-lization with peracetic acid soak and thenflushes the surf ace with steril e-wa ter

spray3. R-103: Provide s hot gaseous-nitrogen purge for drying items beforeentry into the F-123 vacuum chamber Figure 11.- Dolly and basket.4. B-302: Provid es ster iliza tiontemperatures as high as 433 K (160" C)

5. R-302 (st eri lized handling cabinet): Fac ili tat es tr an sfer of items betweenthe F-302 vacuum chamber and the B-302 oven

Figure 12 . - Sample container dolly.F-601 UI ra-High-Vacu um Chamber

Although the F-601 ultra-high-vacuum chamber did not support Apollo 11 o r 12lunar-sample processing directly, a brief description is inserted he re because it ispart of the LRL high-vacuum complex. Special ultra-high-vacuum sam ples, containedin a special environmental sample container (SESC), are passed fr om chamber F-201

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to F - 6 0 1 (fig. l), which is a double-walled differentially pumped chamber that operatesin the 133- to 1.33-nN/m (lo- toa rotary table allow the operator to open the sample container, to subdivide the Sam-ples, and to st or e the samp les in individual containers that ar e called appendages. Eachappendage has its own battery-operated ion pump to perm it shipment of lunar samplesto scien tific investigators while maintaining an ultra-high-vacuum environment (133 to1.33 nN/m (lo- to60 days) , an Apollo 12 SESC was processed successfully in this manner i n the LRLhigh-vacuum complex. The F - 6 0 1 chamber is pumped out by the use of a turbomolecu-wa l l .

2 to rr ) region. A mechanical manipulator and

2 tor r)) . After the Apollo 12 quarantine period (approximately

lar pump, a sputte r ion pump, an electro static ion pump, and a criogenically cooled

Control ConsoleThe entire LRL high-vacuum complex is operated and monitored from the control

console (fig. 3). This console provides continuous monitoring and recording of allvacuum-chamber pr es su re s (from atmospheric to 1 3 . 3 pN/m tor r)) in the com-plex. Television monitors provide the operator with the procedural sta tus i n the F-201chamber. Control of chamber valves and transfer sys tem s is provided by the us e ofelectronically operated valve actuators and a lighted graphic display of the vacuumcomplex.

2

DEVELOPMENT AND OPERATIONAL D I FFI CULT1ESMaintenance of the Vacuum Environment

The vacuum system is inherently an excellent quarantine facility because a bar-r i e r break would res ul t in an inward flow into the system. The inward flow would re-duce the probability of migrat ion of harmful lunar pathogens from the system. Inaddition, a highly reliable system w a s needed fo r lunar quarantine. That is, samplereceip t prevented normal sys tem maintenance because of the potentially hazardousluna r material . A malfunctioning system component would have to be eithe r isolated,sterilized, and repair ed o r isolated and left inoperative until the end of lunar-samplequarantine. For example, a malfunctioning vacuum pump would be deactivated and leftin that condition until the end of sample quarantine because of the difficulties in st er il i-zation of t he se pumps. Proc edures were generated that allowed other vacuum pumpsin the system to absorb the functions of the inoperative pump with a slight los s in flexi-bility. A defective component in a section of the header would be repaired by means ofisolating the section fr om the re s t of the system (by valve closures) , heat sterilizing tokill any lunar organisms, repai ring o r replacing the defective components, heat ste ri liz-ing to kill any te rr est ri al organi sms that were accumulated during repai r, and openingthe repaired section to the rest of the sys tem. Anomalies with the turbomolecularvacuum pumps wer e troublesome, particularly before the Apollo 11 lunar-sampleprocessing.

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Before the Apollo 11 sample-processing checkout and simulations, oil migrationfr om the pumps to the vacuum chambers occurred, particularly during bakeout of thevacuum complex. Investigation revealed the following so ur ce s of the problem.1. Excessive atmospher ic backfilling of the turbomolecular pumps2. Ineffective coldtrapping by the pumps3 . Irr egul ar preventive maintenance of the pumps4. Migration of oil vapor s during high-temperature bakeoutDuring initial sys tem buildup, which continued almost to the Apollo 11 launch, thevacuum chambers had to be rai sed to atmospheric pre ss ure for rep air or modifications.The initial procedure w a s to backfill the complete vacuum complex from gaseous-nitrogen inlets in the pump area. The correlation between oil contamination in the vac-uum chambers and the number of times the vacuum complex w a s backfilled w a s noted.The nitrogen gas flowing past the liquid-nitrogen cold traps created a warming effect onthe tr ap s and thus released oil vapors that were ca rrie d into the chambers. Closely

associated with th is problem w a s the manual method of fi lling the nitrogen co ldtraps ofthe pumps by means of a dewar. The tempe rature of a properly filled coldtrap wouldbe maintained for a maximum of 2 hours. Occasionally, a coldtrap warmed up beforethe allocated time and released trapped oil vapor because the trap was filled improperlyo r because an excessive gas load from the vacuum complex depleted the liquid nitrogenat a fas ter than normal rat e. An indication of this ea rly warmup w a s a sudden ris e inheader pres sure . Also, the manual filling method expended excess ive manpower toser vice the trap s because the dewar had to be filled at a remote station, transported,and connected to the individual pumps.The approach taken to c or rect the liquid-nitrogen filling problem w a s to substi-tute a fully automatic filling sys tem. This approach included running insula ted liquid-nitrogen lines to the coldtraps and installing a liquid-nitrogen sensing control unit. Themethod was not completely acceptab le because, during the tim e that no liquid nitrogenw a s ordered by the sensing control unit, the liquid nitrogen in the supply lines wouldwarm and convert to pressu rized gaseous nitrogen. Safety pop-off valves were installedin the event the gaseous-nitrogen p ressure became too great. Then, when additionalliquid nitrogen w a s orde red by the sensing control unit, the occurrence of a turbulentflow of gaseous/liquid nitrogen resu lte d in sp lashing the liquid nitrogen on the sensingcontrol unit and closing the co ldtrap i nlets with an inadequate amount of liquid nitrogenin the coldtraps. Also, this turbulent flow caused external liquid-nitrogen leakage atthe coldtrap inlets.Rather than make the automatic filling system more complex to corr ect the prob-lems and because at least one man w a s always present when the pumps were operating,a compromise between the completely manual and the completely automatic filling sys-tems w a s developed.A bypass line w a s added at each inlet to each liquid-nitrogen coldtrap, and anoverflow line w a s installed at each coldtrap. Both lines terminated in a single storagevessel. To f i l l each coldtrap, the opera tor opened the valve to the bypass line and


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observed the flow until only liquid nitrogen (no gaseous nitrogen) w a s flowing into thecoldtrap. H e observed the overflow line until liquid-nitrogen flow occurred and thenterminated the liquid-nitrogen flow to the coldtrap. A s experience w a s gained, theoper at or s we re able to adjust the inlet nitrogen flow to each coldtrap so that a trickleof liquid nitrogen from the overflow line into the s torage ve ssel would ensu re that thecoldtrap had a full liquid-nitrogen level. This ability w a s useful particularly duringsuch peak gas-load periods as temperature bakeout of the complex. Th is filling methodrequi red minimum effort by the pumproom operator .

sto rag e vessel. The opera tor then closed the bypass line and opened the inlet to the

Several procedural changes were incorporated to furthe r reduce excessive gasloads on the liquid-nitrogen coldtraps during the backfilling of the pumps fo r modifica-tion of the vacuum chambers.The fi rs t and most important change w a s to eliminate the frequent backfilling ofthe pumps to atmospheric pressure. R a t h e r than backfilling the vacuum complex f ro mthe pump area, the pumps were isolated from the complex by valves just above theliquid-nitrogen coldtraps, and the pumps continued pumping on the isolated coldtrap sec-tion. The backfilling then proceeded fro m the chamber area so that nitrogen flow wastoward the pump area. Thi s procedure further reduced the possibility of air borne con-tamination to the chamber area.The vacuum complex w a s pumped down by roughing wi th a single coldtrapped3 31.42-m /min (50 t /min) pump fo r the low-vacuum range . Th is pump is isolated at

a pre ssu re of 133 N/m (1 to rr ), and the turbomolecular pumps open again to the vac-uum complex to continue the pumpdown sequence. Thus, the turbomolecular pumpsdure incr eas ed the mechanical reliability of the pumps.

2wer e never exposed to higher pre ss ur es than operating pre ssu res . Also, this proce-

During simulations before the Apollo 11 sample processing, frequent fai lur es ofatmosphere s ea ls in the pumps were noted. These fai lur es resulted in excessive oilleve ls i n the pumps because additional oil w a s added to the pumps to replace oil thatleaked pas t the atmospheric seals . Th is condition would have been intolerable duringan Apollo mission; therefore, a detailed, regular preventive maintenance program w a sst ar ted fo r the pumps. In addition, as pa rt of the pre mis sion operations, the pumpswere overhauled completely. Consequently, no vacuum-pump f ail ure s occ urr ed duringApollo miss ion opera tions.

To eliminate the possibility of oil-vapor migration during the high- temperaturebakeout of the vacuum complex, the vacuum-pump he aders we re maintained at a slightlylower temperature so that any migration would remai n i n the header area (i.e. , the oilwould colle ct on the cooler s urfaces) , In addition, a temporary liquid-nitrogen coldtrapw a s insta lled in the glove chamber through a glove port to condense and collect anyorganic oil vapors i n that area. After bakeout, liquid-nitrogen flow to the chamber cold-tr ap and the header coldtraps w a s maintained until these i tem s wer e removed fro m thecomplex fo r cleaning. The header coldt raps were then rein stall ed. This procedureprevented the liber ation of trapped organ ics back into the vacuum complex, Becausethese pro cedu res we re used, the organic background in the F - 2 0 1 complex during theApollo 11 and 12 sample processing was l es s than 1 p/m.

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The major problem associated with maintenance of the vacuum environment w a sthe lack of time at vacuum pr es su re s to enable purging of outgassing mater ial f romchambers. Between February 1, 1969, and the launch date of the Apollo 1 1 mission(July 16, 1,969), thr ee major mission simulations wer e conducted with the vacuum com-plex. Because of the time spent in prepar ing f o r simulation (cleaning cha mbers beforeand after each simulation, loading and unloading tools) and the time spent in solvingprob lems identified during the simulations, the vacuum complex w a s at atmosphericpre ss ure during most of the 5.5-month period. Fo r a vacuum sys tem, the time toreach a low operating pr es su re is directly proportional to the time spent exposed toatmospheric gases. Simply, thi s is the time nec essa ry to pump the monolayers of at-mospheric gas es absorbed in the metal surface s of the chamber s. These gas es ab-sorbed by the metal during atmospheric exposure a r e outgassed at vacuum pressuresand, for a leaktight system, are the predominant constraint i n reaching vacuum pr es -su re s less than 133 mN/m to rr ). Hence, even with the vacuum bakeout, a weekof pumping time on the complex w a s required to reach the minimum operating pressureof 0 . 1 3 3 mN/m to rr ) fo r the Apollo 11 sample processing. In transferring itemsfr om the atmospheric decontamination cabinets to the F - 2 0 1 processing chamber, 3 to4 hour s were required for the F- 123 pressure-equalizat ion chamber pumpdown at thebeginning of t h e Apollo 11 sample processing.

22

Few modifications were made to the vacuum complex between the Apollo 11 andThe vacuum12 sample-processing periods because of the short time between the end of sample proc-es sing of Apollo 11 mate ri al and the launch of the Apollo 1 2 spacecraft.complex was maintained either at vacuum or purged with dry gaseous nitrogen duringmos t of th is period. Consequently, by the end of the Apollo 12 sample processing, thetime required for the F- 123 pressure-equal ization chamber pumpdown w a s only 10 to15 minutes. This reduction in pumpdown time greatly acc elera ted the tr ans fer of i te msto and from the F - 2 0 1 vacuum glove chamber and eliminated the necessity for expendingmanpower to provide parallel processing and transfer operations for timely sample

processing.Between the Apollo 12 and 1 4 missions, no in te rior modificat ions of the vacuumglove chamber were made, and the chamber eithe r w a s held at vacuum or purged withdry gaseous nitrogen to minimize exposure to atmospheric gas es. Consequently, asystem (outgassed) pumpdown of less than 4 hours w a s needed to reach base pr es su re(between 1 3 . 3 and 1 . 3 3 pN/m (lom7 ndprocessing of samples a fter the Apollo 11 and 12 missions (the sum mer and fall of 1970),the shor t te st pumpdown times allowed the sample personnel to as si st in chamber proc-ess ing and vacuum t ra ns fe r operations without impeding the timely sample processing.Operational communications problems were greatly reduced and operational reliabilitywas increased.

2 to rr )) in the vacuum complex. During

A consequence of the prolonged pumpdown of the vacuum complex before theApollo 11 sample processing was failure of the ion pumps. A l l the l ar ge ion pumps hadto be replaced before the Apollo 11 sample processing. The life cycle of a n ion pumpis directly proportional to the minimum operational pr es su re . Fo r example, the life2of an ion pump is approximately 32 000 hours at 0 . 1 3 3 mN/m (imately 320 hours at 1 3 . 3 mN/m ( tor r). After the vacuum-complex configuration

tor r) and is approx-2

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11 sample processing, overgloves that had been dipped were received, and the se gloveshad mandrels approximately the si ze of the pr es su re gloves. These s mal ler , Viton-cover ed overgloves were lined with silicone to provide str ength to the thin Viton cover-ing. Unfortunately, the se overgloves and a r m assemb lies did not a rr iv e until 2 weeksbefore the Apollo 11 launch; therefore, no time w a s available for operational qualifica-tion tests.

Figure 14. - Glove and w r i s tassembly.

W r i s t ring-

Figure 15. - Side view of glove andw r i s t assembly.

O u i c k d i s c o n n e c tT O v e r g l o v e

O vers leeve

L e a l 1 e p a r a t o rD y n a m i c s ea lI

Figure 16.- Overglove sleeve and glove assembly.

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The bulk (fines) ALSRC was tr an sf er red into the F-201 vacuum processing cham-ber on November 26, 1969, and sample processing began. On November 27, the right-hand pre ss ure glove failed. This failure resulted in a pressure rise in the F-201 vac-uum glove chamber to at leas t 1729 N/m (13 to rr ). Seventy percent of the lunar rocksi n the ALSRC were exposed to this pr es su re ; however, the remai nder of the roc ks weresealed i n a vacuum environment. This s et of pre ss ur e ar m and glove assemb lies w a schanged without heat sterilization based on the argument that, because the overgloveshad remained intact, the int ers titi al space between the pressure-glove assembly andthe overglove assembly was not contaminated with lunar ma ter ial . Investigation re -vealed failu re of the metal pivot point between the pressure-glove metal she ll and theadduction/abduction w r i s t ring (fig. 14). Thi s pivot point was designed to reli eve pre s-sur e on the nylon fabric i n the thumb and finger; with the pivot-point separation, at-mospheric pressure (103.4 kN/m (1 5 psia)) w a s exerted fully on the nylon fabric. Th ispr es su re resulted in separation of the fabric fr om the metal she ll of the glove and im-plosion of the chamber.

2

2

On December 4, operations personnel noted that some spl itting of the overglovesw a s occurr ing between the finger s. The decision w a s made to replace the overglovesat vacuum and to inspect the pre ss ur e gloves at the sam e time. Inspection of the pre s-2sur e gloves in the 0.133-mN/rn to rr ) environment revea led that the pivot pointon the left pr es su re glove was failing.

Sample process ing w a s halted, and plans and procedures to change out the pre s-su re gloves were initiated. A s a re su lt of removing the overgloves, the int ers tit ialarea was lunar contaminated, and the process of simply backfilling the chamber andremoving the gloves was not possible. The following steps were taken to change thepre ss ure gloves.1. All lunar material in the F-201 vacuum glove chamber w a s t ransferred to the

F-207 sample-storage carousel and isolated.2. The F-201 vacuum glove chamber w a s backfilled to slightly le s s than atmos-pheric p re ss ur e to prevent lunar contamination of the ambient environment.3 . A "glove-change chamber" was fabricated and sea led to the chamber glovepo rt s. This glove-change chamber contained a sp ar e pre ss ure a rm and glove assemblyin a protective bag and the necessary tools to accomplish the pressure -glove changeout.4. Using neoprene a r m s and gloves in the collapsible glove-change chamber , anoperator interchanged the defective a r m and glove assembly and the new a r m and gloveassembly. Before inserting the new ar m and glove assembly into the glove-change

chamber, the opening i n the new assembly , through which the opera tor in ser ted hisa rm , had been covered to prevent lunar contamination and, th ere fore, steri lizationdamage to the new arm and glove assembly.5. The defective a r m and glove assembly then was inse rted into the protectivesea led bag and the inte rio r of the glove-change chamber sterilized with peracetic acid.


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6. The glove-change chamber was removed fr om the glove-port ar ea of theF-201 processing chamber. The defective ar m and glove assembly was left in thesealed bag until quarantine release.After the Apollo 12 sample processing, rigorous quality-acceptance tests wereincorporated to identify defective a r m and glove assemblie s before the assemblies were

used in processing lunar samples. This testing included leak testing of both overarmand glove assemblies and pr es su re ar m and glove assemblies . Fatigue te st s were per-formed in a one-arm-and-glove chamber (F-401) to qualify the a r m and glove assem-blies fo r use in the F-201 processing chamber. An operating limit of 150 hours w a sestablished for each a r m and glove assembly. The assembly was inspected, requalified,and, if necessary, refurbished.Actions taken to cor re ct the specific problems identified during the Apollo 1 2sample process ing were to fab ricate a 100-percent-reinforced overglove with emphasison the a reas between the finge rs and to redesign the w r i s t pivot point by incorporatingmore durable metal (301 half-hard s tainles s steel). The new ar m and glove assembli eswere satisfactory, and no fail ure s occurre d during 2 months of operat ion in the F-201

and F-401 glove chambers.Ad a p ta b i l i t y o f Tools a n d C o n t a i n e r s t o O p e r a t o r s ,G lo ve s, a n d V a c u u m E n v i r o n m e n t

Tool design and modification continued throughout the Apollo lunar-sample proc-ess ing in the F-201 vacuum glove chamber as scientific requi rements were added or de-leted and problem a re as were identified. However, all tools and containers (figs. 9, 10,and 17 to 27) had to meet basic requirements to ensure proper operations in the chamber.The operator had to handle the tools with the vacuum gloves. Even with the opti-

mum glove design, working in the vacuum gloves was difficult compared to normalhandling in atmospheric-type gloves. The ar m severe ly re st ri ct ed the working volume;therefore, tools were developed to compensate for this deficiency. Using the pr es su rea r m and glove assembly with the 103.4-kN/m (15 psia) pr es su re differential ac ro ssit required much effort by the glove operator (figs. 6 and 13 to 16). Because ther ewa sa definite limi t on the weight an operator could handle in the F-201 vacuum glove cham-ber, lifting jacks (fig. 17) were developed.

2

The average time that an operator could work efficiently i n the gloves was approx-imately 15 minutes, although th is time var ied with individual ,op erators and tasks. Oneindividual w a s able to work for 1 hour, whereas others could work only 10 minutes.However, the policy was to change ope rator s approximately every 15 minutes. A taskwas particularly tireso me f or the glove operator if the task requi red the operator towork with his elbows elevated above the glove wrist s; this position would occur i f a con-tainer or tool fixture was very high o r very near the chamber b reastp late (or both). Anexample of this type of task was the sealing of the la rg e 3.3-liter bolt-type containers(fig. 9) used for storing lunar s amples. If the container o r tool fixture was too faraway, e fforts by the glove operator to work at the limit of his reach put excessive st ra inon the glove and increased the possibility of glove fai lure. Hence, containers and toolfix tur es had to be designed o r modified to funclion within these constrain ts. The fix-tu re fo r holding containers in place during sealing operations is illustrated i n figure 20.

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Figu r e 17 . - ALS RC jack F - 2 0 1 - 1 3 9 .

.,.-_.- .

Figure 18. - ALSRC opening p l ie rs (SEZ 6104697-301) .24


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.I (4 1111 ,.",,.1 1 hSI '- *

Figure 19. - Ratchet and a95-centimeter(0.375 inch) drive (S K 67606-110).

Figure 20. - Canholder assembly(SDZ 6 106027- 301).

Figure 21 . - Five-centimeter (2 inchSCOOP (SEZ 36104724-301).

Tool and container m ateri als we reselected to minimize outgassing in vacuumand contamination of the lunar sample.Approved ma te ri al s fo r fabrication werestainless steel, aluminum, and Teflon.Teflm was used to provide Searing sur=faces. A rigorou s cleaning procedure was

, . r . r . i - > l ~ < , / / I ( I , I * ,-..- s8 -

Figure 22. - Hammer (SEZ 36104728-301).pe rf or med on the tools and containers before their ins ertion into the F-201 pr ocess ingchamber. Proble ms we re encountered with movable, clean metal su rf ac es (such ascontainer bolts) and tool dies galling in the vacuum environment. To ens ure prop eroperation, molydisulfide w a s selected as the only lubricant acceptable fo r movable, con-tacting metal surfaces.

Intric ate ta sk s and the lifting of tools and containers were perfor med with the in-dex finger and thumb of the glove assembly. The remaining finge rs wer e used mainlyfo r physical supporting functions. Because the vacuum glove configuration resu lted i nlack of dexterity , ove rs ized tools (figs. 18 and 24) and containers w er e designed, withemphasis on eas e of operation. A l l edges handled by the ope rator needed broad radiito avoid tea ring the gloves. To control these design const raints and cleaning requir e-ments, a quality-assurance program w a s incorporated.

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The two bas ic types of containersused for storage of lunar samp le s areshown in figures 9 and 10. The bolt-typecontainers (fig. 9) we re the prima ry con-tainers f o r storage in the vacuum sys temand fo r sample transf er to other labora-to ri es . The "single action" containers(fig. 10) were designed for quick storageof lunar samples i f deteriora tion of thevacuum environment occur red (high leak-age rat es, etc.). Qnce sealed in a vac-uum environment, the single-action con-environment. By con tra st, the bolt-topcontainer bolt sc rew s ar e an integral pa rtof the li d s o that while the bolts a r e backed out of the containe r, the lid is lifted.Hence, the vacuum-sealed conta iners may be opened in an atmos pheric environmentbecause the bolts ac t as jacking sc re ws against the force crea ted by the pre ss ur e d i f -f erent ial between the container vacuum int er ior and atmospheric exter ior.

Figure 23.- T-handle (SEZtainers may be opened only in a vacuum 36106104-301).

Figure 24. - Tweezers (SEZ 36104416-301).

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Figure 25. - Floor brush ( S E Z 36104408-302).

Figur e 26. - Universal handle (SEZ 36104404-301).To redu ce stora ge volume for tools in the vacuum complex, se ve ra l types of con-tainers and t o d s might use a common fixture or item. The container holder (fig. 20)could be adapted to hold all bolt-type container s iz es by simply reve rs in g the top andbottom and removing or inserting pins in the fixture. Several common types of tools(figs. 21, 22, and 25) used a common overs ized "universal" handle (fig. 26). An ea r-li e r vers ion of the universa l handle with a tool attached is shown in fig ure 19. A fewtools such as the T-handle (fig. 23) we re s imi lar to conventionally designed tools.The se tools enabled the glove operator to perform the s ame ta sks i n a high-vacuum en-vironment t hat a n unencumbered technician might perfo rm with common tools in anambient environment.

M e c h a n i s m s o f T r a n s f e r B e tw e e n A s s oc ia te dV a c u u m C h am b e rs

The m ost unnecessary, complicated system in the vacuum complex is the transfersystem. A s stated earlier, the original vacuum complex w a s designed and fabricatedto handle the tra ns fe r of sam ples and tools into two identical sample-p rocessing cham-be rs . Only one samp le chamber (the F-201 vacuum glove cha mber) was funded andbuilt. However, the tr an sf er syst em and the connecting chambers in the original design

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were built. Anunnecessar y tr an sf er cham-ber (F- 123) w a s t h e result. This chambercontained (for the original design) a rotarytrack to dire ct the incoming ite m, in eitherof two 90" directions, to the sel ect edp roc -ess ing chamber. With only one pro ces sin gchamber, this design complicated, length-ened, and reduced the reliabil ity of thetransfer process.

To tran sfer it ems to and from theF-123 chamber, the rotar y tr ack had to bepositioned carefu lly to receive the item o rthe transfer dolly would roll into the cham-ber. Trans fers among chambers wereperformed by rolling the tra nsf er dolly andbasket along an inverted T-r ail , propelledby an extensor syste m. The extensor isattached to a Teflon rac k, which, in turn ,is driven by a handwheel-operated vacuum-sealed gear drum. An extensor pin andtab on the dolly engage a cam mechanismon the ra il that can latch the dolly to or un-latch the dolly fr om the tr ans fer rail. Theexte rnal handwheel con trol s of the transfe rsyste m ar e shown in figure 1.This cam mechanism is positionedin the centralized or neut ral portion of the

tr an sf er chamber (F-202, F-302, and

t

Figure 27. - Radiation counting samplecontainers and tools.F-203). The purpose of the mechanism is to lock the dolly into a position so that theval ves on either end of the tr an sf er chamb er may be opened o r clo sed without hittingthe dolly. The valve closure provides chamber isolation when ite ms a r e being trans-fe rr ed between chambers at different pr es su re levels. Also, the extensor syste m hasto be placed in its neut ral position to prevent damage during valve closu re. To con-tinue transfer, the extensor system is moved to its unlatch position, which frees thedolly, and the dolly and basket are moved into the terminating chamber. The extensorthen is returned to its neut ral position. Two types of container dollies a r e ill ust rat edin figures 11 and 12 . The dolly and basket i n figu re 11 are used for storing specialsm al l sample containers. Shown in the photograph a r e the dolly ball-bearing wheelsthat ride on the inverted T-monorai l, the two dolly tabs, and the dolly pin that act iva testhe latch/unlatch mechanism. Figur e 1 2 is an example of one of the bolt-top containerstor age dollies. One of the dolly tabs is shown at the top ce nt er of the dolly.

The toler ances of the extensor position ind icato rs in the handwheel ar e very loosein comparison to the crit ica l tolerances of the latch and unlatch cam mechanism. Hence,an operator had to be very care ful during the tran sfe r procedure. A mista ke usuallyjammed the trans fer system. Ja ms in the system occurred i f rail alinement amongchamb ers was inc orr ect because of misalinement by the op era tor , heavy loads changing

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the alinement, or changes as a re su lt of the rotary rail action in the F-123 trans ferchamber and the storage-carousel chambers. Also, damage to the extensor pin, thedolly tab, or the cam resulted in a jam. The critical and unnecessary tolerances ofthe ca m mechanism a r e illus trated by the following example.In retrieving a sample dolly fr om the s torage carousel, a glove opera tor acciden-tally ripped the left overglove on the dolly extensor tab. To avoid possible future dam-age to overgloves, the rectangula r tab on each dolly was rounded off 0.079 cent imete r(0.031 inch) at the upper co rne rs (figs. 11and 12). After th is configuration change, thedolly would ja m in the tran sf er cam mechanism. To cor re ct this jamming of the tra ns-f e r sys tem , the rounded-off mat eri al had to be rein stated on all dollies.Because the design, fabr ication, and installation of a simpler transfer systemwas not feasible in t e rms of the high-vacuum complex downtime and the tim e intervalbetween missions , a workaround solution w a s formulated. Detailed procedures wereimplemented to prevent operator e rr or . Simultaneous operations were halted duringtr an sf er procedures to avoid communication problems. A' re tr ieva l rod w a s designed

and fabr icated to allow the glove opera tor to ret rieve the dolly if a jam did occur. Therod was variable i n length (i.e., rod lengths could be added o r subtracted ) to facilitateaccess to various transfe r system area s.The preceding actions were compromises to avoid installing a new system. The

pos ure to atmospheric gas es and maintenance tasks. The vacuumenvironment qualitygained after the Apollo 11 sample process ing would not have been recoverable i f a newtransf er sy st em had been installed between subsequent missions.

compromises avoided degradation to the vacuum complex as the res ul t of extended ex-

Samp l e ProcessingThe basi c sample-processing procedure i n the vacuum syste m w a s as follows.1. Receive the ALSRC.2. Meas ure the background gases in the sealed ALSRC with a residual-gasanalyzer.3. Open the ALSRC and inventory the contents.4. Tra nsf er o r st or e the special containers.5. Sieve lunar mate rial to sepa rate rocks and lunar soil (fines).6. Pr ep are the Radiation Counting Laboratory (RCL) sample and bioprimesamples.7. Weigh and photograph individual rock samples.8. Perf or m microscopic examination. (Scientific obser ver per fo rm s thisexamination. )

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9. Split selected ro cks and tra nsf er the chips to the physical science lab orator ies(the Physical-Chemical T es t Laboratory, the Gas Analysis Laboratory, the Thin Sec-tion Laboratory, and' the Mineral Separa tion Labora tory).10. Perform postsplit weighing and photography.

11. Conduct lunar soi l (fines) processing and loading of specia l principal inves ti-gator containers.Three sam ples wer e time-cri tical in processing out of th e high-vacuum complex:the RCL sample, the bioprime sample, and the "biopool" sample . The RCL samplehad to be tra ns fe rr ed to the RCL as quickly as possible to identify the pre sen ce ofshort- half- life isotopes. The concentrat ions of the short-lived cosmic- ray-produced

nuclides of elements such as vanadium, 48V (half life = 16. 2 days), and manganese,52Mn (half life = 5.7 days), a r e detected by nondestructive gamma-ray spectroscopy.The bioprime and biopool samples were used by the biological laboratory to establishquarantine-release criter ia. The bioprime sample had to be tr an sf er red fro m the vac-uum complex within 3 to 5 days. This sample was chosen fr om the lunar soil (fines)materi al, The biopool sample, tra ns fe rr ed fr om the system after 15 to 17 days, w a scomposed of chips fr om the lunar rocks. During Apollo 11 sample processing, chipsfrom all the returned r ocks were required. During Apollo 1 2 sample processing, onlychips from major types of rocks wer e required.

The RCL sample procedure changed most radically before the Apollo 11 and 12sample processing. Preparation of the RCL sample w a s complicated because it wasthe only sample to be tra ns fe rr ed to a laboratory outside the quarantine b ar ri e r andbecause knowledge of the orienta tion of the sample in the container was necessa ry foraccura te re su lt s in performance of the experiment. Because of the aforementionedrequirements, the following procedures were incorporated.The originally conceived RCL procedures a r e outlined as follows.1. The sample is scan photographed in the F-201 vacuum glove chamber. Scanphotography consists of a se r i es of photographs taken as a plane of light is projectedaround the perimete r of the rock. This plane of light tr an sv ers es the height of therock as the platform is moved in 0.318-centimeter (0.125 inch) intervals. Th es e pho-tographs define the sample contours so that a rough model of the rock can be fabricated.Concave surfaces that a r e not defined adequately by the light projec tion are defined bythe modeler f ro m re co rd (positive) photography.2. A s p l i t mold with indium-tinned edges is fabricated fro m the model as an

inner container for the sample.3 . The inner container is put into a lar ge transfer container.4. The transfer container i s evacuated, heat steril ized, and tra nsf er red intothe F-201 glove chamber.


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5. The inner container is removed fro m the transfer fixture, and the trans ferfixture is tra nsf err ed from the chamber.6. The lunar sample is ins erted in the inner container mold, and the containermold is inserted i n an outer container.7. The outer container is positioned i n a heating fixtu re that melt s the indium onthe outer edge of the inner container. This melting produces a leaktight seal betweenthe two halves of the oute r container.8. The container is removed fr om t h e sealing fixture and insert ed i n a specialvessel.9. The special vessel is sealed by the glove operator and pressurized for aspecified time with gaseous nitrogen at pr es sur es between the chamber operating pres -

sure and 101.3 kN/m (1 atmosphere).10. The container is removed fr om the special vessel after reevacuation of thevessel and inser ted in a leak-check vessel.11. The atmosphere in the sealed leak-check vesse l is monitored by a residual-gas ana lyzer to dete rmine whether nitrogen is leaking fr om the container. This moni-toring indicates whether the nitrogen has penetrated the container through a faulty sea lduring the nitrogen-pressurization step.Th es e procedures were complicated, lengthy, and dangerous. The excessiveweight of the transfer fix ture caused misalinement of the vacuum sys tem tr ansfer rail.The operator had to spend a minimum of 2 hours i n opening the container to retrievethe inner container fr om the transf er fixture. The weight of the fixtu re prevented theglove operator fr om reassembling and transf erring the fixture from the chamber. Nosuccessful seals were ever made wi t h the indium-melting technique. Because the vac-uum gloves prevented any transfer of heat to the glove operator, a high probability ofse ve re damage to the gloves existed. Also, i f an operational er r o r or pressurizedve sse l failur e occu rred during the nitrogen-pressurization sequence, damage fr om ex-posing the glove chamber to high-vacuum pressures w a s probable.By the t ime of the Apollo 11 sample processing, a simple container sealed byusing the s am e technique used fo r other sample containers (O-ring type) w a s designedand fabricated. The container had a spring-loaded sta inless -steel net that held the Sam-ple in a fixed location in the container. The tools and container components a ssocia ted

with this RCL sample container a r e shown in figure 27. Extensive te st s before contain-e r u se established successfu l sealing techniques. Ju st before sealing, photographs ofthe sample in the container were taken to record orientation of the sample. The scan-photography procedure was retained to help in fabricating models of the sample. Thesemodels wer e useful in standardization te st s of the radiation counting experiment. Thesample container w a s sealed in th re e Teflon bags as an additional precaution i n tr ans-fe rr ing the container through the quarantine barrier.

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The Apollo 11 scientific requirem ents necessitated that all rock samples be splitand that the daughters (spl it portions of the sample) be distr ibuted to other analyticallaboratories. A special tool w a s developed by the NASA Je t Propul sion Labora tory(J PL ) to split the lunar rocks and to cold-weld seal the lunar-rock chips into a specialaluminum container. The JP L rock sp litt er and se al er developed fo r the Apollo 11sample processing w a s a third version . The excess ive weight and complexity of thefirst tw o rock s pli tte rs and se al er s made handling by the glove opera tor difficult.. Thethir d rock splitter and seale r used a ball-screw design in developing 142 kilonewtons(16 tons) of for ce . To convert fr om the rock-splitter mode to the container-sealingmode was a tedious procedure in which the spl itte r j a w s were replaced with dies forsealing the 3.81-centimeter ( 1 . 5 inch) diameter aluminum containers. These aluminumcontainers were used to transfe r sma ll lunar chips and lunar s oil (fines) to other labor-ator ies and principal investigators.

Difficulties wer e experienced in handling these aluminum containers. The con-ta ine rs were damaged easily, and the sealing sur faces had to be fr ee of contamination.Lunar dust or oxidation (formed before container installation in the chamber) on thesealing sur face s prevented the cold-welding p roce ss. Glove ope ra tor s developed thetechnique of brushing the container sur face s with a stainless-steel wire brush just be-fore sealing.

U s e of the splitting capability of the J P L rock sp litt er and se al er during the Apollo11 sample processing was minimal. Most rock sample s could be split with a hammerand chisel . The angular shape of many luna r-rock samples and the shor t j a w s of therock spli tter were not compatible in providing well-controlled splitting.For the Apollo 12 sample processing, a manual rock splitter w a s developed thatis similar to a miniature guillotine. The glove operator applies the splitt ing for ce witha hammer. Controlled splitting w a s improved greatly. Not all lunar sam ples weresplit during the Apollo 12 sample processing. The decision to spli t a specimen w a sbased on the requirement to sample different types of lunar rocks instead of each indi-

vidual rock (the Apollo 11 requirement ). The elimination of much postsp lit photogra-phy a n d weighing greatly accelerated mission processing. Retaining the J P L rock split-ter and seale r in its container-sealing mode (as during the Apollo 11 sample processing)eliminated much effort by the glove operator .Maintaining cleanliness of the F - 2 0 1 vacuum glove chamber during both Apollo 11and Apollo 12 sample processing w a s a problem. The tool and container clu tter im-peded efforts by the glove operator to perform this function. For the Apollo 1 2 sampleprocessing, the clutter w a s reduced greatly a s tool and container requirements wer ebetter defined. In addition, only the most proficient of the Apollo 11 glove operatorswere retained. These glove oper ato rs became efficient at reducing lunar dust collectedon the chamber floor, although the ope rators w ere impeded by the vacuum gloves in

recovering the dust. Aluminum foi l w a s found to be very useful in reducing contamina-tion of the chamber floor; the foil was spr ead beneath the working a rea to catch thedust. This foil could then be folded by the glove operator to hold the dust.


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D e v e l o p m e n t of a n E f f ec ti ve O per a t i on a l TeamA s with the vacuum environment, the quality of t eam effort on the vacuum sampleimproved with experience. Before the Apollo 11 sample processing, personnel spentmost of the time, including simulations, in solving hardware prob lems. A s a result,training of per sonnel i n sample handling and procedural protocol was minimal.Operational personnel worked overtime in correcting design and fabrication de-ficiencies of the vacuum processing complex.gram w a s initiated for the F - 2 0 1 vacuum processing complex to avoid these types ofIn April 1969, a quality-assurance pro-problems i n the future.Procedure s were in continuous revision until a few weeks before the Apollo 11lift-off as scientific requi rements fo r handling the lunar ma ter ial changed. Thi s revi-sion w a s par tly an at tempt to cover a ll contingencies in handling the unknown quality andquantity of the lunar ma ter ial .To provide continuous dir ect support fo r the F - 2 0 1 vacuum complex for the Apollo11 sample processing, 15 people wer e requi red. Th is number included glove-chamberpersonnel, atmospheric decontamination personnel, sample- tra nsfer personnel,communication- and control-console ope rators , and contr actor and NASA super visors .Even with the planned contingencies, most decisions concerning sample handlingwere made by management personnel outside the quarantine ba rr ie r through a communi-cation link. To evaluate the situation behind the ba r ri er , coordinate the 'decisionmakingprocess, and then transmit the decision to the operational personnel w a s a slow proce-dure.The trans fe r of i tems ( samples and tools) through the atmospheric decontamina-

tion cabinets was slow as a result of the drying pr ocess in the cabinets. The peracetic-acid-sterilized i tems had to be flushed with water and dried before inserti on in theF - 1 2 3 transfer chamber. Transfer through the vacuum transfer chambers was slow be-cause of the time requ ired fo r transfer chamber pumpdown. This pumpdown periodw a s requir ed to achieve an optimum vacuum environment. In addition, tr an sf er s weredelayed because of the signature approval required to t rans fe r each individual item fromthe vacuum sample-process ing complex. Approval fo rm s had to be either transmit tedo r reproduced ac ro ss the ba rr ie r to facilitate signature approval by the quarantine-control officer.Because of the p re ss ur e to expedite the unique Apollo 11 lunar samples and tocompensate fo r the delays mentioned previously, simultaneous tr ansfer and F- 201 glove

chamber procedures were conducted. In addition, the combination of procedures re-sulted in the processing of severa l samples simultaneously in the F - 2 0 1 glove chamber.For example, the glove operato r would be chipping or canning a sample while one o rmore samples were being weighed or photographed. Consequently, a number of sam-ple s were exposed to vacuum pr es su re s of approximately 1995 N/m (1 5 tor r ) (as con-traste d to normal operating pressu re near 0 . 1 3 3 mN/m to rr )) in the F - 2 0 1 vac-uum glove chamber when the vacuum glove failed.

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By the time of the Apollo 12 sample process ing, the lunar samples had fewer un-known qualit ies; and the speed of process ing, except that of biological protocol andshort-life radiation counting samples, w a s not as critic al. In addition, seve ra l hard-war e and procedural changes were made to expedite sample processing.

Requirements and procedures we re better defined. Most decisions concerningprocessing of the lunar material w ere made by the vacuum-laboratory te st di re ct or be-hind the quarantine ba rr ie r. Because the dire ctor w a s famil iar with the situation, anyproblem could be resolved quickly. A heat st er il iz er was added to the vacuum complexto avoid excessive delay of inbound tools and con tainers through the peracet ic-acid-sterilization system. Also, this addition reduced clutter in the glove chamber becausetools and containers could be tra ns fe rr ed into the chamber without exposure to the per -ace tic acid. Hence, the loading of al l potentially requi red tools and containers beforesample receipt w a s not necessary. The procedures fo r t ransf er rin g outbound samplecontainers through the peracetic-acid- ster ilizat ion cabinets w e r e simplified and stand-ardized to avoid time spent in obtaining signature approval.

Simultaneous operations were eliminated to reduce communication difficulties andto avoid simultaneous exposure of an excess ive number of sampl es in the glove cham-ber. Unfortunately, initial lunar-rock inventory was still in pro ce ss when the vacuumglove failed. Consequently, a number of rocks were exposed to high pre ssure . All thelunar s o i l (fines) and a third of the rock sample s were protected in the F-207 stor agecarousel.

Vacuum transfer operations did not have to be performed simultaneously withglove operations. The pumpdown of the F-123 tr an sf er chamber had been reduced fr omthe 4 o 5 hou rs required a t the beginning of the Apollo 11 sample processing to between10 and 15 minutes a t the end of the Apollo 12 sample processing. Hence, glove opera-tions could be halted long enough to complete a transfer.Implementation of these procedure s effectively reduced the number of personnelrequired for continuous direct support of the F-201 vacuum complex to half the numberrequired for the Apollo 11 sample processing (a reduction from 15 to 7 persons) .Several types of problems were identified during the Apollo 11and 12 sampleprocessing. The major types were as follows.1. Monitoring and recording vacuum p re ss ur e automatically from atmospheric

pressure to I. 33 ~ N / ~ ~ ( I O - *orr )2 . Monitoring smal l changes i n the vacuum glove inters titi al pr es su re to detectchanges in the physical condition of the vacuum gloves3 . Monitoring more effectively the entire vacuum complex and increasing the re-sponse time of the console controller to changes in the vacuum-environment sta tus4. Providing more effective hea ter control on the chambe rs and the complex net-work of the vacuum headers

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Investigation of the vacuum gloves after the processing revealed no physical dam-age. Moreover, no a r m and glove assembly failu res occurred.With only five basic operating personne l, the F- 2 0 1 vacuum sample-processingcomplex began to reach i t s full potential during this postmis sion processing .

CONCLUD ING R E M A R K SAfter the vacuum complex had begun to reach its full potential, the complex didnot support any subsequent Apollo missions. No samples were return ed f ro m the Apollo1 3 mission, and scientific requirem ents fo r vacuum sample processing were deleted be-fo re the Apollo 1 4 mission.Perhaps the most imposing constra ints on the vacuum complex in reaching i t s fullpotential to support the Apollo 1 1 and 1 2 miss ions w er e time and lack of flexibility. Toomuch basic development work was still being accomplished on the complex 6 months be-fore the Apollo ll sample processing ; identi fication of operat ional problems and refine-

ment of operational t as ks should have been the pr im e objectives during this pe riod. Ofcourse , a portion of the basic development work w a s a re sul t of the continuing effort tomeet both scientific and quarantine requirem ents in handling the unknown char ac te ri s-ti cs of lunar mate rial. Requirement conflicts developed, pa rticu larly concerning Sam-ple packaging and transfer ring , that had to be resolved. Incorporat ion of the new re-quirements res ulted in development of new container s and the addition of a heat steri-li ze r to the complex. Effor ts expended on the se types of development problems reducedthe tim e devoted to procedural training of the personnel and to purging of the vacuumcomplex.The vacuum processing complex w a s a complicated system because of the neces -s i t y to satisfy the quarantine and scientific requireme nts and to implement contingency

actions, which sometimes were contradictory; therefore, compromises were required.The situation was unique; an unknown entity (lunar ma ter ial ) was being returned f ro mthe Moon. Nothing was known about the potential effect of Earth atmospheric pr essur eand gases on the material. The presence o r absence of potentially harmful lunar orga-ni sm s was unknown. To help answer these and other questions, the high-vacuum com-plex was designed; because speed of processing w as important in getting answe rs quick-ly, a second glove chamber was par t of the original complex design. Although the sec -ond glove chamber w a s eliminated because of funding cuts, the transfe r c ham bers fo rconnecting the existing glove chamber and the second proposed chamber remained i nthe complex. Therefore , the complexity of having two glove chambers still remainedbecause the tran sfe r system, a complicated vacuum header, and a la rg e control con-sole still remained. The resulting operational and engineering problems were identi-fied and solved.

After the Apollo 11 mission, many of the questions concerning lunar materi alwere answered. It was established that lunar material could be safely handled at atmos-pheric press ure and its integrity preserved in a dry-nitrogen environment.

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After the Apollo 12 mission, the requirement for vacuum lunar samples had di-minished and gr ea te r ease and speed of lunar-sample processing w a s shown in the dry-nitrogen cabinets. However, even with the problems discussed previously, the LunarReceiving Labora tory high-vacuum complex proved to be the best compromise in meet-ing both quarantine and scienti fic requi rements i n handling the initial receipt.of thelunar mat eri al on Earth.

Lyndon B. Johnson Space CenterNational Aeronautics and Space AdministrationHouston, Texas, April 9, 19769 4- 0- 2-01-72

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Apollo Experience Report Lunar-Sample Processing in the Lunar Receiving Laboritory High-Vacuum...

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