Chamber Study Compares Air Distribution Strategies to Cut Airborne Infection Risk

What happened

In a simulated double-bed patient room, researchers tested mixing ventilation (MV), occupant-targeted ventilation (OTV), and wall attachment ventilation (ATT) using SF6 as a virus surrogate. When the infector was a patient, ATT kept mean concentrations lower than MV at 40 L/s, and its average contaminant removal effectiveness was 42.7% higher than MV at 17 W/m² and 80 L/s. When the infector was a staff member, OTV significantly improved dilution at 80 L/s. Raising airflow from 40 to 80 L/s cut infection probability in the exposed area, with 8 of 12 tests achieving at least a 50.0% reduction.

Why it matters

Healthcare-associated infections have risen across European hospitals, and this study provides evidence for selecting local air distribution systems to improve microenvironmental safety in patient rooms. The findings can guide practical ventilation design to reduce airborne infection risk between patients and staff.