Tracer gas is a suitable surrogate of exhaled droplet nuclei for studying airborne transmission in the built environment
Tracer gas is a suitable surrogate of exhaled droplet nuclei for studying airborne transmission in the built environment
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示踪气体是呼出液滴核的合适替代品，用于研究建筑环境中的空气传播
DOI：
10.1007/s12273-020-0614-5
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发表时间：
2020-02-21
影响因子：
5.5
通讯作者：
Niu, Jianlei
中科院分区：
文献类型：
--
作者：
Ai, Zhengtao;Mak, Cheuk Ming;Niu, Jianlei
人与人之间的空气传播是许多传染病的有效和主要呼吸道传播途径（CDC 2007, 2017; Hodgson et al. 2012; Li et al. 2015）。全世界每年约有300万人死于下呼吸道感染（世卫组织，2018年）。空气传播已被证明发生在封闭的室内空间内（Liu et al. 2017; Ai and Melikov 2018），同一楼层的不同房间之间（Wu et al. 2016），同一建筑物的不同公寓之间（Gao et al. 2009; Ai and Mak 2016; Mu et al. 2016），甚至高密度城市地区相邻建筑物之间（Yu et al. 2004）。了解疫情的传播特点、高危途径和影响因素，对制定有效的防控措施具有重要意义，有助于减少死亡和病假人数，降低医疗成本。人际间空气传播的整个过程包括感染者产生传染性飞沫、传染性飞沫核在空气中传播以及接触者吸入传染性飞沫核（Nicas et al. 2005; Tang et al. 2006; Wei and Li 2016）。人类的呼吸、说话、咳嗽和打喷嚏可以产生数以万计的飞沫（Duguid 1946; Tellier 2006; Chao et al. 2009）。这些液滴中的大多数瞬间蒸发到初始大小的一半，并成为液滴核（Nicas et al. 2005）。这些液滴核在空气中传播受到重力、惯性、通风流量、人体边界层流量和呼吸流量等因素的影响（Melikov 2015; Nazaroff 2016）。液滴核在空气中的扩散通常是通过实验测量或计算流体动力学（CFD）方法获得的浓度分布来评估的。通常用示踪气体或粒子来模拟液滴核，本文称之为示踪气体模拟或粒子模拟。
Airborne transmission between persons is a valid and major respiratory transmission route for a number of infectious diseases (CDC 2007, 2017; Hodgson et al. 2012; Li et al. 2015). Worldwide there are approximately 3.0 million deaths annually caused by lower respiratory infections (WHO 2018). Airborne transmission has been shown to occur within an enclosed indoor space (Liu et al. 2017; Ai and Melikov 2018), between different rooms on a same floor (Wu et al. 2016), between different flats in the same building (Gao et al. 2009; Ai and Mak 2016; Mu et al. 2016) and even between adjacent buildings in high-density urban areas (Yu et al. 2004). Understanding the transmission characteristics, high-risk routes and influential factors is of great importance for formulating effective control measures, which would in turn contribute to reduced number of deaths and illness leaves as well as lowered health care costs. The whole process of airborne transmission between persons involves the generation of infectious droplets from an infected person, the spread of infectious droplet nuclei in the air and the inhalation of infectious droplet nuclei by an exposed person (Nicas et al. 2005; Tang et al. 2006; Wei and Li 2016). Human breathing, talking, coughing and sneezing can generate tens of thousands of droplets (Duguid 1946; Tellier 2006; Chao et al. 2009). Most of these droplets evaporate instantaneously to half of their initial size and become droplet nuclei (Nicas et al. 2005). These droplet nuclei spread in the air with the influence of factors like gravity, inertia, ventilation flow, human body boundary layer flow and respiratory flow (Melikov 2015; Nazaroff 2016). The spread of droplet nuclei in the air is usually evaluated by concentration distribution obtained using either experimental measurements or computational fluid dynamics (CFD) methods. The droplet nuclei are commonly simulated using a tracer gas or particles, which are termed as tracer gas simulation or particle simulation in this paper.