Comparative study on aerosol fate of mixed ventilation and attachment ventilation in a dental clinic

• Attachment ventilation in dental clinics is compared to mixed ventilation. • An upper outlet in attachment ventilation removes aerosols more effectively. • The optimal ACH for aerosol attenuation in dental clinics is between 5 and 8 h⁻¹. Dental clinics have become hotspots for potential virus transmission due to the nature of their procedures. This study introduces a wall-based attachment ventilation (AV) model to investigate aerosol diffusion and the impact of ventilation control within dental clinics, utilizing both experimental and simulation methodologies. A full-scale laboratory has been established for the experimental validation of numerical simulations based on Computational Fluid Dynamics (CFD). The findings highlight that the AV mode, particularly when the air outlet is situated in the upper region, exhibits superior aerosol removal compared to the lower outlet configuration. Additionally, the research identified a critical point in aerosol reduction related to the air change rate per hour (ACH), which falls between 5 and 8 h −1 based on this study. Compared to mixed ventilation (MV), the AV system demonstrated approximately 10% higher escape rate, 10% lower deposition rate, and 3% higher suspension rate. These findings provide valuable insights for reducing infection risks among healthcare workers in dental clinics.