International Centre for Indoor Environment and Energy, Department of Civil Engineering, Technical University of Denmark, Copenhagen, Denmark.
Department of Architecture, Faculty of Science and Engineering, Waseda University, Tokyo, Japan.
Indoor Air. 2019 Nov;29(6):993-1004. doi: 10.1111/ina.12589. Epub 2019 Aug 6.
This study examined the characteristics of the exhaled airflow pattern and breathing cycle period of human subjects and evaluated the influence of pulmonary ventilation rate and breathing cycle period on the risk of cross-infection. Measurements with five human subjects and a breathing thermal manikin were performed, and the peak exhaled airflow velocity from the mouth and the breathing cycle period were measured. Experiments on cross-infection between two breathing thermal manikins were then conducted in a full-scale test room, in which the pulmonary ventilation rate and breathing cycle period were varied systematically. Both peak flow velocity and breathing cycle length varied considerably between different subjects. The breathing cycle period in a standing posture was 18.9% lower than in a sitting posture. The influence of pulmonary ventilation rate and breathing cycle period extended up to a separation distance of 1.0 m between the two manikins. Increasing the pulmonary ventilation rate of the exposed person greatly increased the risk of cross-infection. Decreasing the breathing cycle period from the widely used "6 second" value led to a considerable increase in the risk of cross-infection. Standing posture resulted in a higher risk of cross-infection than sitting posture.
本研究考察了人体呼气气流模式和呼吸周期的特征，并评估了肺通气率和呼吸周期对交叉感染风险的影响。对五名受试者和一个呼吸热模型进行了测量，测量了从口腔呼出的最大气流速度和呼吸周期。然后在一个全尺寸测试室中对两个呼吸热模型之间的交叉感染进行了实验，系统地改变了肺通气率和呼吸周期。不同受试者之间的最大气流速度和呼吸周期长度变化很大。站立姿势的呼吸周期比坐姿短 18.9%。暴露者的肺通气率和呼吸周期的影响可以延伸到两个模型之间 1.0 米的距离。增加暴露者的肺通气率会大大增加交叉感染的风险。将广泛使用的“6 秒”值的呼吸周期缩短会导致交叉感染风险显著增加。站立姿势比坐姿更容易导致交叉感染。
