Use of wearable ventilation for reducing the infection risk of healthcare workers in isolation wards: A numerical study

Abstract

This study investigates the protective effectiveness of a novel head-mounted air supply (HAS) system on healthcare workers (HCWs) in COVID-19 isolation wards. The study employs computational fluid dynamics (CFD) to explore the effectiveness of the HAS and the infection probability for HCWs during constant exhaling and coughing of patients. It also studies the effect of air changes per hour (ACH) and exhaust outlet locations in the isolation ward on the infection probability of the HCW. Additionally, the effectiveness between the HAS and various types of common masks is compared. Results indicate that when the flow rate of the HAS reaches 10 L/s with supplying clean air, the infection probability of the HCW can be reduced from approximately 30 % without protection to below 0.18 %. Patients' coughing increases the infection probability of the HCW by approximately tenfold within a short period, and wearing the HAS can effectively reduce the effect of patients’ coughing on the HCW. When ACH increases, the infection probability of the HCW decreases. Wearing the HAS can mitigate the effects of changes in ACH, with an infection probability below 0.18 % at 9 ACH or above. Ceiling-level exhausts are more effective than floor-level exhausts in removing pollutants from the ward. Under experimental settings, HAS with suitable parameters may be more effective than commonly used masks in terms of reducing the infection probability of the wearer. These findings provide valuable references for the application of wearable ventilations in hospital environments.