AAAR 33rd Annual Conference
October 20 - October 24, 2014
Rosen Shingle Creek
Orlando, Florida, USA
Abstract View
A Non-Specific Monodisperse Aerosol Generation System
JONATHAN ESHBAUGH, Francisco Romay, Shanna Ratnesar-Shumate, Paul Dabisch, Johns Hopkins University Applied Physics Laboratory
Abstract Number: 523 Working Group: Instrumentation and Methods
Abstract Size specific monodisperse aerosols have been used to investigate respiratory and non-respiratory deposition and thus absorption of inhaled biological aerosols. Generally, the aerosol of interest is produced with a monodisperse aerosol generator, which uses either a spinning disk or an oscillating orifice to atomize a liquid. Biological aerosols, or aerosols which contain spores, viruses, or proteins are typically aerosolized from a liquid suspension within the confines of a biological safety cabinet. Monodisperse generators that utilize an orifice typically aren’t compatible with liquid suspensions while other monodisperse generators aren’t compatible with the vibration and reduced access of a biological safety cabinet. Additionally, the interaction of viability, infectivity, or activity of the biological particle, atomization stress, and particle size is difficult to study since the atomization required to generate the monodisperse aerosol is fixed. Thus an inertial sorting monodisperse generation method compatible with varying biological suspensions, the confines of a biological safety cabinet, and any atomization technique that can generate particles within the size ranges of interest was designed and evaluated. The design coupled an ultrasonic atomizer to a series of clean air core virtual impactors designed by MSP to generate a monodisperse or near-monodisperse aerosol at three discrete particle sizes from a biological suspension. Airflow for the entire system was controlled and monitored with valves, laminar flow elements, and differential pressure gauges. Characterization tests with minimum essential media demonstrated production of aerosol count distributions with modes of 1.4, 6.3, and 11.4 micro-meters and geometric standard deviations of 1.3, 1.2, and 1.3, respectively. The system design as well as experimental results will be presented.