Compatibility of integrated physical barriers and personal exhaust ventilation with air distribution systems to mitigate airborne infection risk

Abstract

This study investigated the effectiveness of integrating desk partitions and personal exhaust ventilation to mitigate airborne infection risks in areas where people sit closely together. Experiments were conducted in a test chamber equipped with different air distribution systems, including two different mixing and one displacement ventilation. N2O tracer gas was utilized to study airborne transmission between occupants. Results showed effectiveness of preventive measures varied depending on air distributions. In the absence of preventive measures, mixing ventilation systems exhibited higher infection risk compared to displacement ventilation. After the introduction of physical barriers, N2O concentration increased at two measurement points in presence of one of the mixing ventilation systems. In contrast, the other mixing ventilation and displacement ventilation showed a reduction in N2O concentration, up to 63 % and 43 %, respectively, depending on measurement points. Combination of physical barriers and personal exhaust ventilation consistently reduced N2O concentration by 34 % to 83 %, depending on measurement point's location and type of air distribution. Furthermore, higher airflow rates of personal exhaust increased efficiency of proposed strategy in limiting infection risk. This study supports employing physical barriers and personal exhaust ventilation to reduce airborne infection risks. Tailoring preventive measures to specific air distribution system is crucial.