Contamination of hospital environments due to droplet dispersion during coughing: visualization of over-table wiping

This paper aims to provide materials for the preparation of manuals for nosocomial infection, in medical institutions. First, we reproduce the hospital bed environment, which serves as a source of infection. To simulate contamination in the hospital bed environment, we developed an apparatus that sprays simulated cough droplets (with mired alcohol and fluorescent paint powder). Additionally, we reproduced the hospital bed environment using a desk and an over bed table. Simulated cough droplets were sprayed onto the bed environment model, and the over bed table was wiped using two different methods. Before learning the proper wiping technique, contamination areas were spread further. However, after learning the correct wiping technique, the contaminated areas were significantly reduced. Furthermore, we used Structure from Motion (SfM) to reconstruct a 3D human model of the hospital bed environment to confirm 3D contamination situation. In addition, simulated cough droplets were sprayed onto protective clothing, and a 3D model was obtained using RGB-D camera to observe the contaminated areas and gain a deeper understanding of contamination spread. Based on these experimental results, understanding contaminated areas and verifying proper wiping techniques can contribute to improving the manual of cleaning accuracy of healthcare workers.