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. 2015 Oct 7;121:1365–1374. doi: 10.1016/j.proeng.2015.09.023

Documentary Research of Human Respiratory Droplet Characteristics☆

Hualing Zhang a,b,⁎, Dan Li a,c, Ling Xie a, Yimin Xiao a,b
PMCID: PMC7128962  PMID: 32288921

Abstract

Respiratory droplet characteristics are key to determine the droplet-borne pathogen transmission, which provide scientific basis for formulating the disease prevention from droplet transmission and control measures. Through studying the data information from existing documents, this paper gives the respiratory droplet characteristics, like size, concentration, velocity, etc. Meanwhile, droplet evaporation, droplet-borne pathogen activity and their transmission are discussed. The droplet size is no significant difference with human health level, gender and age. The size of droplets produced by health people is between 0.1 and 10 μm, it produced by patients is between 0.05 and 10 μm, and the patients’ droplet concentration is higher. The coughed droplet concentrations change with the size into a peak rule. The velocity of the cough droplets is the biggest, the range of 10 to 25m/s, the transmission distance is more than 2m.

Keywords: Airborne droplet, droplet size, transmission, infection

Footnotes

☆

Peer-review under responsibility of the organizing committee of ISHVAC-COBEE 2015.

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