Lu Yalin, Niu Dun, Zhang Sheng, Chang Han, Lin Zhang
Department of Architecture and Civil Engineering, City University of Hong Kong, China.
School of Human Settlements and Civil Engineering, Xi'an Jiaotong University, Xi'an, China.
Build Environ. 2022 Aug 15;222:109440. doi: 10.1016/j.buildenv.2022.109440. Epub 2022 Jul 31.
Air distribution is an effective engineering measure to fight against respiratory infectious diseases like COVID-19. Ventilation indices are widely used to indicate the airborne infection risk of respiratory infectious diseases due to the practical convenience. This study investigates the relationships between the ventilation indices and airborne infection risk to suggest the proper ventilation indices for the evaluation of airborne infection risk control performance of air distribution. Besides the commonly used ventilation indices of the age of air (), air change effectiveness (), and contaminant removal effectiveness (), this study introduces two ventilation indices, ., the air utilization effectiveness () and contaminant dispersion index (). CFD simulations of a hospital ward and a classroom served by different air distributions, including mixing ventilation, displacement ventilation, stratum ventilation and downward ventilation, are validated to calculate the ventilation indices and airborne infection risk. A three-step correlation analysis based on Spearman's rank correlation coefficient, Pearson correlation coefficient, and goodness of fit and a min-max normalization-based error analysis are developed to qualitatively and quantitatively test the validity of ventilation indices respectively. The results recommend the integrated index of and to indicate the overall airborne infection risk and to indicate the local airborne infection risk respectively regardless of the effects of air distribution, supply airflow rate, infectivity intensity, room configuration and occupant distribution. This study contributes to airborne transmission control of infectious respiratory diseases with air distribution.
空气分布是对抗 COVID-19 等呼吸道传染病的一项有效工程措施。由于实际操作方便，通风指标被广泛用于指示呼吸道传染病的空气传播感染风险。本研究调查通风指标与空气传播感染风险之间的关系，以提出用于评估空气分布的空气传播感染风险控制性能的合适通风指标。除了常用的空气龄（）、换气效率（）和污染物去除效率（）等通风指标外，本研究还引入了两个通风指标，即空气利用效率（）和污染物扩散指数（）。通过对不同空气分布（包括混合通风、置换通风、分层通风和下送通风）服务的医院病房和教室进行 CFD 模拟，以计算通风指标和空气传播感染风险。基于斯皮尔曼等级相关系数、皮尔逊相关系数、拟合优度的三步相关性分析以及基于最小-最大归一化的误差分析分别用于定性和定量地检验通风指标的有效性。结果表明，无论空气分布、送风量、感染强度、房间配置和人员分布的影响如何，综合指标和分别表示总体空气传播感染风险和局部空气传播感染风险。本研究有助于通过空气分布控制传染性呼吸道疾病的空气传播。
