Course Description:
Recorded at AIHce EXP 2022
Presentations
Use of DNA-tagged liquid tracer aerosols to simulate the emission, transport, and management of respiratory aerosols in buildings
Reducing exposure to infectious aerosols is critical for controlling airborne pathogen transmission. During the COVID-19 pandemic, professional societies, including the CDC, WHO, ASHRAE, and AIHA, provided guidance on airborne pathogen exposure mitigation that includes dilution ventilation and filtration. Continued evaluation of recommendations and their application in real buildings is important for improving guidance for reducing transmission risk. The tools used in such evaluations must closely simulate the particle type of interest, in this case aerosols emitted from the respiratory system. DNA-tagged liquid tracer aerosols are a novel approach for characterizing how liquid aerosols, such as respiratory emission particles, are transported in buildings and can be used to assess the effectiveness of aerosol exposure mitigation methods. Compared to tracer gas and solid tracer particle methods, DNA-tagged liquid tracer aerosols can be modified such that their physicochemical composition and emitted size distribution simulate respiratory emissions, while DNA concentration simulates pathogens carried by respiratory particles. Presented are the results of two studies: 1. A chamber test comparing DNA-tagged aerosol decay rates to tracer gas and particle size distribution decay rates as ventilation rate and filtration type varied; and 2. an intervention study in an office comparing the spatial distribution and concentration of DNA-tagged tracer aerosols as air change rate varied.
CO-AUTHORS
I. Arvelo, SafeTraces, Pleasanton, CA, USA
F. Pagone, RHP Risk Management Inc., Chicago, IL, USA
J. Persky, RHP Risk Management Inc., Chicago, IL, USA
C. Carpio, Department of Agricultural and Applied Economics, Texas Tech University, Lubbock, TX, USA
P. Arnold, SafeTraces, Pleasanton, CA, USA
ACKNOWLEDGEMENTS & REFERENCES
E. Machuca, SafeTraces, Inc., Pleasanton/CA, USA
A. Elizondo, SafeTraces, Inc., Pleasanton/CA, USA
AUTHOR
Nicholas Clements, Ph.D., SafeTraces, Inc. Denver, CO
United States of America
CO-PRESENTER
Mr. Erik Malmstrom, SafeTraces, Inc. Pleasanton, CA
United States of America
Contact Hours:
1
Presentation Date:
05/24/2022
Presenters:
Nicholas Clements, PhD
