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Mathematical estimation of the level of microbial contamination on spacecraft surfaces by volumetric air samplingMicrobiological sampling methods presently used for enumeration of microorganisms on spacecraft surfaces require contact with easily damaged components. Estimation of viable particles on surfaces using air sampling methods in conjunction with a mathematical model would be desirable. Parameters necessary for the mathematical model are the effect of angled surfaces on viable particle collection and the number of viable cells per viable particle. Deposition of viable particles on angled surfaces closely followed a cosine function, and the number of viable cells per viable particle was consistent with a Poisson distribution. Other parameters considered by the mathematical model included deposition rate and fractional removal per unit time. A close nonlinear correlation between volumetric air sampling and airborne fallout on surfaces was established with all fallout data points falling within the 95% confidence limits as determined by the mathematical model.
Document ID
19740062566
Document Type
Reprint (Version printed in journal)
Authors
Oxborrow, G. S.
Roark, A. L.
Fields, N. D.
Puleo, J. R. (U.S. Public Health Service, Center for Disease Control, Cape Canaveral, Fla.; Sandia Laboratories, Albuquerque N. Mex., United States)
Date Acquired
August 7, 2013
Publication Date
April 1, 1974
Publication Information
Publication: Applied Microbiology
Volume: 27
Subject Category
BIOTECHNOLOGY
Funding Number(s)
CONTRACT_GRANT: NASA ORDER W-13062
Distribution Limits
Public
Copyright
Other