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At least 73 records · Page 4

Microbiological sampling of returned Surveyor 3 electrical cabling

A piece of electrical wiring bundle running from the television camera to another part of the spacecraft was selected for microbiological examination. Sampling methods are discussed. The results presented show that no viable microorganisms were recovered from the part of the Surveyor 3 cable which was tested. Factors that could have contributed to the sterility of the cable are thermal vacuum testing, natural dieoff, change in pressure during launch, and lunar vacuum and temperature.

Knittel, M. D.

Microbiologic assay of space hardware.

Review of the procedures used in the microbiological examination of space hardware. The general procedure for enumerating aerobic and anaerobic microorganisms and spores is outlined. Culture media and temperature-time cycles used for incubation are reviewed, along with assay systems designed for the enumeration of aerobic and anaerobic spores. The special problems which are discussed are involved in the precise and accurate enumeration of microorganisms on surfaces and in the neutralization of viable organisms buried inside solid materials that could be released to a planet's surface if the solid should be fractured. Special attention is given to sampling procedures including also the indirect techniques of surface assays of space hardware such as those using detachable or fallout strips. Some data on comparative levels of microbial contamination on lunar and planetary spacecraft are presented.

Favero, M. S.

Microbiological sampling of spacecraft cabling, antennas, solar panels and thermal blankets

Sampling procedures and techniques described resulted from various flight project microbiological monitoring programs of unmanned planetary spacecraft. Concurrent with development of these procedures, compatibility evaluations were effected with the cognizant spacecraft subsystem engineers to assure that degradation factors would not be induced during the monitoring program. Of significance were those areas of the spacecraft configuration for which special handling precautions and/or nonstandard sample gathering techniques were evolved. These spacecraft component areas were: cabling, high gain antenna, solar panels, and thermal blankets. The compilation of these techniques provides a historical reference for both the qualification and quantification of sampling parameters as applied to the Mariner Spacecraft of the late 1960's and early 1970's.

Koukol, R. C.

Microbiological surveillance of food handling at NASA-MSFC

A microbiological surveillance program of cafeterias and snack bars was conducted to supplement the inspections by NASA Medical Center personnel and to gather information for cafeteria management to pinpoint areas of possible contamination. The work conducted under the program from its inception in January, 1972, to its termination on September 15, 1972 is summarized. Ten food handling facilities were included in the surveillance at NASA-MSFC.

Beyerle, F. J.

Microbiological assay of the Marshall Space Flight Center neutral buoyancy simulator

A neutral buoyancy simulator tank system is described in terms of microbiological and medical safety for astronauts. The system was designed to simulate a gravity-free state for evaluation of orbital operations in a microorganism-free environment. Methods for the identification and elimination of specific microorganisms are dealt with as measures for a pure system of space environment simulation.

Beyerle, F. J.

The chemical/physical and microbiological characteristics of typical bath and laundry waste waters

Chemical/physical and microbiological characteristics are studied of typical bath and laundry waters collected during a 12 day test in which the untreated waste waters were reused for toilet flush. Most significant changes were found for ammonia, color, methylene blue active substances, phosphates, sodium, sulfates, total organic carbon, total solids, and turbidity in comparison with tap water baseline. The mean total number of microorganisms detected in the waste waters ranged from 1 million to 10 to the 7th power cells/m1 and the mean number of possible coliforms ranged from 10 to the 5th power to 1 million. An accumulation of particulates and an objectible odor were detected in the tankage used during the 12 day reuse of the untreated waste waters. The combined bath and laundry waste waters from a family of four provided 91 percent of the toilet flush water for the same family.

Hypes, W. D.

Project environmental microbiology as related to planetary quarantine

Microbiological analyses of soil particles allow for the following conclusions: (1) there is a considerable range in the values of aerobic, mesophilic microbial counts associated with different size soil fractions; (2) as soil particle size increases, there is an increase in the mean microbial concentration per particle; (3) plate counts of aerobic, mesophilic organisms in unheated soils yielded a mean concentration of about six organisms per particle for the smallest soil fraction; (4) aerobic, mesophilic counts for sonicated particles heated at 80 C for 20 minutes yielded mean values of about two organisms per particle for the smallest particles; (5) some actinomycetes associated with the soil fractions could survive dry heat treatment at 110 C for one hour; and (6) soil particles stored under ambient laboratory conditions for 2.5 years aerobic, mesophilic plate counts which were comparable or slightly greater than the counts for more recently collected soil.

Pflug, I. J.

Evaluation of membrane filter field monitors for microbiological air sampling

Due to area constraints encountered in assembly and testing areas of spacecraft, the membrane filter field monitor (MF) and the National Aeronautics and Space Administration-accepted Reyniers slit air sampler were compared for recovery of airborne microbial contamination. The intramural air in a microbiological laboratory area and a clean room environment used for the assembly and testing of the Apollo spacecraft was studied. A significantly higher number of microorganisms was recovered by the Reyniers sampler. A high degree of consistency between the two sampling methods was shown by a regression analysis, with a correlation coefficient of 0.93. The MF samplers detected 79% of the concentration measured by the Reyniers slit samplers. The types of microorganisms identified from both sampling methods were similar.

Fields, N. D.

Apparatus for microbiological sampling

An automatic apparatus is described for microbiologically sampling surface using a cotton swab which eliminates human error. The apparatus includes a self-powered transport device, such as a motor-driven wheeled cart, which mounts a swabbing motor drive for a crank arm which supports a swab in the free end thereof. The swabbing motor is pivotably mounted and an actuator rod movable responsive to the cart traveling a predetermined distance provides lifting of the swab from the surface being sampled and reversal of the direction of travel of the cart.

Wilkins, J. R.

A thermal vacuum-UV solar simulator test system for assessing microbiological viability

Microorganisms were exposed to a simulated space environment in order to assess the photobiological effect of broad spectrum, nonionizing solar electromagnetic radiation in terms of viability. A thermal vacuum chamber capable of maintaining a vacuum of 0.000133n/sq m and an ultraviolet rich solar simulator were the main ingredients of the test system. Results to date indicate the system to be capable of providing reliable microbiological data.

Ross, D. S.

ASTP chemical and microbiological analysis of potable water

The Apollo-Soyuz Test Project procedures for potable water system servicing and the results of preflight and postflight chemical and microbiological analyses of the water are discussed. Tables show results of the analyses. The effectiveness of the water system is evaluated.

Sauer, R. L.

Skylab environmental and crew microbiology studies

The objectives of the Skylab microbiology studies were to detect the presence of potentially pathogenic micro-organisms on the crewmembers and their spacecraft and to obtain data which would contribute to an understanding of the response of the crew's microbial flora to the space flight environment. These data were interpreted in light of the theories of microbial simplification, intercrew transfer of medically important microorganisms, in-flight auto infections, and postflight microbial shock, which have been proposed by various authors.

Gerald R Taylor

Microbiological profiles of the Viking spacecraft

Planetary quarantine requirements associated with the launch of two Viking spacecraft necessitated microbiological assessment during assembly and testing at Cape Canaveral and the Kennedy Space Center. Samples were collected from the Viking Lander Capsules (VLC), Orbiters (VO), and Shrouds at predetermined intervals during assembly and testing. Levels of bacterial spores per square meter on the VLC-1 and VLC-2 were 1.6 x 10 squared and 9.7, respectively, prior to dry-heat sterilization. The ranges of aerobic mesophilic microorganisms detected on the VO-1 and VO-2 were 4.2 x 10 squared to 4.3 x 10 cubed and 2.3 x 10 squared to 8.9 x 10 cubed/sq m, respectively. Approximately 1300 colonies were picked from culture plates, identified, lyophilized, and stored for future reference. About 75% of all isolates were microorganisms considered indigenous to humans; the remaining isolates were associated with soil and dust. The percentage of microorganisms of human origin was consistent with results obtained with previous automated spacecraft but slightly lower than those observed for manned (Apollo) spacecraft.

Puleo, J. R.

Methods for microbiological and immunological studies of space flight crews

Systematic laboratory procedures compiled as an outgrowth of a joint U.S./U.S.S.R. microbiological-immunological experiment performed during the Apollo-Soyuz Test Project space flight are presented. Included are mutually compatible methods for the identification of aerobic and microaerophilic bacteria, yeast and yeastlike microorganisms, and filamentous fungi; methods for the bacteriophage typing of Staphylococcus aureus; and methods for determining the sensitivity of S. aureus to antibiotics. Immunological methods using blood and immunological and biochemical methods using salivary parotid fluid are also described. Formulas for media and laboratory reagents used are listed.

Taylor, G. R.

Efficiency tests of samplers for microbiological aerosols, a review

To obtain comparable results from studies using a variety of samplers of microbiological aerosols with different collection performances for various particle sizes, methods reported in the literature were surveyed, evaluated, and tabulated for testing the efficiency of the samplers. It is concluded that these samplers were not thoroughly tested, using reliable methods. Tests were conducted in static air chambers and in various outdoor and work environments. Results are not reliable as it is difficult to achieve stable and reproducible conditions in these test systems. Testing in a wind tunnel is recommended.

Henningson, E.

Treatment bed microbiological control

The effects of microbial fouling on treatment bed (TB) performance are being studied. Fouling of activated carbon (AC) and ion exchange resins (IEX) by live and devitalized bacteria can cause decreased capacity for selected sorbates with AC and IEX TB. More data are needed on organic species removal in the trace region of solute sorption isotherms. TB colonization was prevented by nonclassical chemical disinfectant compositions (quaternary ammonium resins) applied in suitable configurations. Recently, the protection of carbon beds via direct disinfectant impregnation has shown promise. Effects (of impregnation) upon bed sorption/removal characteristics are to be studied with representative contaminants. The potential need to remove solutes added or produced during water disinfection and/or TB microbiological control must be investigated.

Janauer, Gilbert E.

Chemical and microbiological experimentation for development of environmental control and life support systems

Microbiological techniques are under study with a view to the identification of viable microorganisms in liquid cultures, improve the identification of stressed organisms, and determine the biocidal activity of iodine and other chemicals on isolates from recycled water. A quality-assurance program has been implemented to validate data employed in making decisions concerning engineering and human health and safety. Analytical laboratory refinements will strongly aid the development of environmental control and life-support systems.

Whitman, G. A.