The Dry Aerosol Deposition Device (DADD): An Instrument for Depositing Microbial Aerosols onto Surfaces
Abstract
The advent -- 60 years after the concept was first proposed -- of practical self-decontaminating materials coincides with international efforts to prepare for global viral epidemics to highlight a need for a method to rapidly and reproducibly contaminate surfaces with pathogenic bioaerosol particles and representative surrogates. Slow rotation of a single collection stage in a cascade impactor downstream of a Collison nebulizer is demonstrated to deposit by impaction a rotationally symmetric distribution of particles containing a single spore of Bacillus globigii or vegetative Staphylococcus aureus bacterium. The coefficient of variation observed for deposition on glass plates was approx. 14%, significantly less than the acceptance criterion of 20%, and deposition time is approx. 20 min. Particle size distribution can be manipulated -- by changing the nozzle in the Collison, by changing the concentration of inert organics added to the atomization mixture, or both -- suggesting a possibility of selectively depositing larger particles containing multiple organisms.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 2008
- Accession Number
- ADA502105
Entities
People
- Brian K. Heimbuch
- Joseph D. Wander
- Kimberly R. Kinney
- Robert K. Nichols
Organizations
- Applied Research Associates (United States)