In infection prevention, more is not always better for ventilation and partitions
Ventilation and physical partitions are crucial interventions to limit the spread of respiratory illnesses in indoor spaces. However, when used incorrectly, they could worsen air quality and exacerbate infection spread.
Norvihoho et al. simulated the impact of different divider arrangements and ventilation on cough droplet path to reduce viral contagion risk.
“In some instances, increased ventilation might inadvertently redistribute contaminated air within a space rather than effectively removing it,” said author Zhi-Fu Zhou. “Furthermore, wrong positioning of desk partitions can obstruct ideal ventilation airflow to control indoor air quality. Understanding how desk partitions affect airflow and infection spread is crucial for creating healthier work environments, safeguarding employees’ well-being, and minimizing the risk of workplace infections.”
Their model includes three healthy people and one with a respiratory infection, seated in pairs across a table. When the sick person coughs, the researchers studied how the droplets moved and lingered during different partition layouts and ventilation rates.
As predicted, the results of their simulation stress the need for careful consideration of the intervention. Infection risk was lowest when the partitions split all four participants only for low or no ventilation, but high ventilation could lead to the most accumulation of viral particles. Though the partitions reduce the risk for those opposite the divider, a healthy person sitting beside the sick person faces increased risk compared to no partition. Without dividers, the safest scenario involves no ventilation.
“We plan to continue improving our model to incorporate other aspects of diverse environment conditions, ventilation rates, complex office environments, human behaviors, extended long-term dynamics, validating against more experimental data, reevaluating some of the assumptions, and considering different ventilation systems,” said Zhou.
Source: “The effects of desk-partition layout on cough droplet dynamics relating to seasonal influenza,” by Leslie K. Norvihoho, Jing Yin, Yi Liu, Hai-Tao Yu, Yi Jiang, Zhi-Fu Zhou, and Bin Chen, Physics of Fluids (2024). The article can be accessed at https://doi.org/10.1063/5.0186922 .