Hygroscopic growth and size distribution data for: In situ measurements of human cough aerosol hygroscopicity

The airborne dynamics of respiratory droplets, and the transmission routes of pathogens embedded within them, are governed primarily by the diameter of the particles. These particles are composed of the fluid which lines the respiratory tract, and is primarily mucins and salts, which will interact with the atmosphere and evaporate to reach an equilibrium diameter. Measuring organic volume fraction (OVF) of cough aerosol has proved challenging due to large variability and low material volume produced after coughing. Here, the diametric hygroscopic growth factors (GF) of the cough aerosol produced by healthy participants were measured in situ using a rotating aerosol suspension chamber and a humidification tandem differential mobility analyser. Using hygroscopicity models, it was estimated that the average OVF in the evaporated cough aerosol was 0.88±0.07 and the average GF at 90% relative humidity (RH) was 1.31±0.03. To reach equilibrium in dry air the droplets will reduce in diameter by...

呼吸道飞沫的空气动力学行为，以及其中包埋的病原体传播途径，主要由颗粒直径决定。这类颗粒由呼吸道内衬的体液构成，主要成分为黏蛋白与盐类，其会与大气相互作用并蒸发至平衡直径。由于咳嗽后产生的物质体积较低且变异性较大，测量咳嗽气溶胶的有机体积分数（organic volume fraction, OVF）一直颇具挑战。本研究采用旋转式气溶胶悬浮腔与加湿串联差分迁移率分析仪，原位测量了健康受试者产生的咳嗽气溶胶的直径吸湿增长因子（hygroscopic growth factors, GF）。借助吸湿模型，研究估算得出：蒸发后咳嗽气溶胶的平均有机体积分数为0.88±0.07，在90%相对湿度（relative humidity, RH）下的平均吸湿增长因子为1.31±0.03。若要在干燥空气中达到平衡，飞沫的直径将缩小……