Aerosols are one of the major sources of cross-infection. The main purpose of this study is to analyze the effects of heat gain, airflow rate, air distribution, and the location of an infector on the airborne transmission and infection probability in a meeting room. In a six-person meeting room the droplet nuclei of an infected person were simulated with tracer gas (SF) generated by a thermal breathing manikin. An overhead perforated duct (OPD) and low velocity unit (LVU) were used and their performance was compared. With OPD, the average contaminant removal efficiency in the breathing zone was quite uniformly between 0.9 and 1.1. With LVU, the average contaminant removal efficiency varied greatly between 0.2 and 10.1. The airborne generation was assumed to be 5 quantum/h by an infected person. The infection probability for every exposed person was found to be quite uniform with OPD, 1.4 % with a heat gain and air flow rate of 38 W/m and 61 l/s and 0.9 % with a heat gain and air flow rate of 60 W/m and 116 l/s after 3 hours’ exposure. However, variation of the infection probability with LVU was significant and the highest risk reached 4 %. The infection probability was lower if the exposed person was farther from the infector, or in the case of OPD if the infector was near the exhaust. With LVU, the infection probability depended on the airflow rate and the relative distance between the supply unit and the exposed person.

中文翻译：

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会议室不同气流分布方式空气传播实验研究

气溶胶是交叉感染的主要来源之一。本研究的主要目的是分析会议室中吸热、气流速率、空气分布和感染者位置对空气传播和感染概率的影响。在六人会议室中，用热呼吸模型产生的示踪气体（SF）模拟感染者的飞沫核。使用了架空穿孔管道 (OPD) 和低速装置 (LVU)，并对它们的性能进行了比较。使用 OPD 时，呼吸区的平均污染物去除效率非常均匀地在 0.9 到 1.1 之间。对于 LVU，平均污染物去除效率在 0.2 到 10.1 之间变化很大。感染者假设空气中的产生量为 5 量子/小时。结果发现，使用 OPD 时每个暴露者的感染概率相当均匀，在增热和空气流量为 38 W/m 和 61 l/s 时感染概率为 1.4%，在增热和空气流量为 60 W 时感染概率为 0.9% /m 和 116 l/s 暴露 3 小时后。然而，感染概率随 LVU 的变化显着，最高风险达到 4%。如果暴露者距离感染者较远，或者在 OPD 的情况下，如果感染者靠近排气口，则感染概率较低。对于 LVU，感染概率取决于气流速度以及供应装置与暴露者之间的相对距离。