American Association for Aerosol Research - Abstract Submission

AAAR 38th Annual Conference
October 5 - October 9, 2020

Virtual Conference

Abstract View


Viable Virus Transport in Ventilation Airflow

TATIANA BAIG, Maria King, Texas A&M University

     Abstract Number: 195
     Working Group: The Role of Aerosol Science in the Understanding of the Spread and Control of COVID-19 and Other Infectious Diseases

Abstract
Currently little is known on how SARS-CoV-2 spreads indoors and its infectability. The objective of this study is to gain more knowledge on the effect of environmental factors on the spread and infectivity of virus aerosols in the built environment. Understanding how the virus transmits indoors would allow for early detection of viral particles in room sized spaces. Bovine coronavirus (BCoV), was used as virus simulant in laboratory experiments conducted in a controlled humidity cabinet at Biosafety Level 2. An air-jet nebulizer was used to disseminate known numbers of BCoV. Particle tracking velocimetry with shadowgraphy techniques was used to monitor the effect of environmental conditions (temperature and relative humidity) on the size distribution and velocity of the virus particles. After aerosolization, the surface in the cabinet was sampled at regular time intervals to assess the number of particles impacted. The samples were quantified using quantitative polymerase chain reaction (qPCR). The virus aerosols that remained suspended in the air were collected using the portable viable bioaerosol collector (VBAC) with a reference air sampler and quantitated by qPCR. To monitor the effect of the ventilation on the virus movement, BCoV aerosols were also disseminated in a ¾ scale ventilated hospital model chamber equipped with several VBAC units operated at 100 L/min. The spatial-temporal distributions of the collected viral aerosols were enumerated using qPCR. Based on air property measurements, aerosol collections and the mechanical blueprint of the model chamber, a computational flow model was created to visualize the entrainment and movement of the virus in the ventilation airflow. Mitigation measures to reduce the spread of the virus were designed and modeled.