Reducing Exposure Risk in Hospital Wards by Applying Stratum Ventilation System

This chapter tests the effectiveness of stratum ventilation to minimize the risk of exposure for enhancing the design of ventilation systems in hospital wards and protecting healthcare workers from respiratory infections. The distribution of contaminants within a two-bed hospital ward housing two patients and one healthcare worker under various ventilation strategies, including stratum ventilation, mixing ventilation, downward ventilation, and displacement ventilation, is compared. To simulate the release of exhaled and coughed contaminants by patients, a tracer gas like CO₂ is employed. The concentration of contaminants and the effectiveness of their removal under different air distribution scenarios are evaluated. The results indicate that stratum ventilation, with two patients exhaling, leads to lower contaminant concentrations in the breathing zone, and demonstrates higher effectiveness in removing contaminants. Furthermore, the study analyzes the concentration of coughed contaminants at various time intervals. The findings suggest that under stratum ventilation, coughed contaminants are rapidly diluted, resulting in a significant reduction in areas with high concentrations. Overall, this research underscores the effectiveness of stratum ventilation in mitigating the exposure risks faced by healthcare workers in hospital wards.