The COVID‐19 virus can transmit through airborne expiratory droplets and thus, the viral transmission can take place between the occupants in the isolated room. With the school re-opening under the current COVID‐19 pandemic, it is urgent to improve the classroom ventilation system to mitigate the risk of virus transmission. The present study developed a particle concentration monitoring network (PCMN) using low‐cost sensors and deployed it to explore the dispersion of the droplet particles under different ventilation settings and aerosol configurations. Our experiment shows the advance of using a low‐cost sensor network on spatiotemporal air monitoring and demonstrates indoor particle concentration level and distribution are strongly impacted by the ventilation setting and source location. Two recommendations on reducing the viral risk in the classroom were derived from the study. The first is the respiratory droplet source, e.g., the instructor, should be in the location such that the particle dispersion opposes the ventilation flow. The second is the air handling unit (AHU) and fan coil unit (FCU) should be both turned on during class hours despite whether there is a need for thermal comfort, as it allows higher and more uniform ventilation flow to resolve the issue of the dead air zone.
Bibliographical noteFunding Information:
The authors thank the support of members of the Center for Filtration Research: 3M Corporation, Applied Materials, Inc., BASF Corporation, Boeing Company, China Yancheng Environmental Protection Science and Technology City, Cummins Filtration Inc., Donaldson Company, Inc., Entegris, Inc., Ford Motor Company, Guangxi Wat Yuan Filtration System Co., Ltd, LG Electronics Inc., MSP Corporation, Parker Hannifin, Samsung Electronics Co., Ltd., Xinxiang Shengda Filtration Technology Co., Ltd., Shigematsu Works Co., Ltd., TSI Inc., W. L. Gore & Associates, Inc., and the affiliate member National Institute for Occupational Safety and Health (NIOSH). URL: http://www.me.umn.edu/cfr/.
© The Author(s).
- Classroom ventilation
- Indoor air monitoring
- Low‐cost sensor