AAAR 33rd Annual Conference
October 20 - October 24, 2014
Rosen Shingle Creek
Orlando, Florida, USA
Abstract View
Characterization of a Rotating Drum System for Bioaerosol Studies in Biocontainment
MICHAEL SCHUIT, Shanna Ratnesar-Shumate, Jamie Kline, John Yeager, Kristin Bower, Paul Dabisch, NBACC
Abstract Number: 44 Working Group: Bioaerosols
Abstract Knowledge of the impact of environmental conditions on the persistence of bioaerosols is critical for public health modeling, the results of which can be utilized to estimate the spread of disease and ultimately inform preparedness and response efforts to emerging agents. While rotating drums for the study of the persistence of bioaerosols have been used for many years, the scope of many previous studies has been limited by the inability to control test conditions or by the biosafety level of the laboratory. The objective of this study was to characterize a novel small rotating drum aerosol chamber capable of controlling temperature, relative humidity, and simulated solar radiation levels in a laboratory operating at Biosafety Level 4. The chamber’s ability to achieve and maintain environmental settings over extended time intervals was tested, and the simulated solar light spectrum and intensity variation were mapped. Additionally, tests were conducted using polystyrene latex (PSL) microspheres to determine the physical decay rate as a function of particle size within the chamber at different rotation rates, and the results were compared with published models from the literature. The data demonstrate that the test system was able to tightly maintain all combinations of environmental parameters tested. A gradient in solar intensity (~15%) over the length of the drum was observed, which may lead to a variation in exposure levels of particles within the chamber. Tests with PSL microspheres showed a marked particle size dependent improvement in retention times when the drum was rotating, although the results did not agree with published models. Regardless, the system was able to maintain particle concentrations of sizes up to 6 micro-meter aerodynamic diameter for periods of time sufficient to measure the inactivation of microorganisms, which will facilitate future work examining the impact of environmental factors on the persistence of microorganisms in aerosols.