Airborne transmission during short-term events: Direct route over indirect route

Abstract

Numerous short-term exposure events in public spaces were reported during the COVID-19 pandemic, especially during the spread of Delta and Omicron. However, the currently used exposure risk assessment models and mitigation measures are mostly based on the assumption of steady-state and complete-mixing conditions. The present study investigates the dynamics of airborne transmission in short-term events when a steady state is not reached before the end of the events. Large-eddy simulation (LES) is performed to predict the airborne transmission in short-term events, and three representative physical distances between two occupants are examined. Both timeaveraged and phase-averaged exposure indices are used to evaluate the exposure risk.The results present that the exposure index in the short-term events constantly varies This is the Pre-Published Version.

Tracing the origin of large respiratory droplets by their deposition characteristics inside the respiratory tract during speech

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