･This study aimed to visualize and measure the flow field of aerosols derived from exhalation (jet flow) during face-to-face encounters with another person and to clarify the viral exposure risk when passing by another person.
･Furthermore, we compared the behavior of the flow fields of aerosols during face-to-face encounters under ventilated versus non-ventilated conditions to assess the aerodynamic characteristics of ventilation and its impacts on the viral exposure risk.
･The peak risk of viral exposure occurs within a 5-s window during face-to-face interactions, irrespective of whether ventilation is adequate or lacking.
