High-speed scattered-light imaging for sizing respiratory droplets
(2023) In Journal of Aerosol Science 174.- Abstract
- The COVID-19 pandemic has illuminated the lack of knowledge regarding the airborne transmission pathway of disease. The pathway consists of pathogens contained in small particles ejected when speaking and coughing. A crucial characteristic of these particles is their size that is connected to the their suspension longevity in the air as well as the location of generation and deposition within a subject’s respiratory system. Sizing of particles launched from the respiratory system is a challenge for a number of reasons: (1) the size of ejected particles varies over a wide range, between sub- to several hundreds of microns, (2) particles are ejected at various speeds in different directions, (3) each single event is unique where for example... (More)
- The COVID-19 pandemic has illuminated the lack of knowledge regarding the airborne transmission pathway of disease. The pathway consists of pathogens contained in small particles ejected when speaking and coughing. A crucial characteristic of these particles is their size that is connected to the their suspension longevity in the air as well as the location of generation and deposition within a subject’s respiratory system. Sizing of particles launched from the respiratory system is a challenge for a number of reasons: (1) the size of ejected particles varies over a wide range, between sub- to several hundreds of microns, (2) particles are ejected at various speeds in different directions, (3) each single event is unique where for example the number of particles can vary greatly between two occurrences of the same event and subject, (4) the size of the particles vary significantly as they evaporate over time. To overcome these challenges and categorize full coughing and speaking events, new measuring methods are needed. In this work, we present, in detail, high-speed scattered light imaging to size liquid particles (droplets) in unique respiratory events. A high-speed camera records scattered laser light at 16 000 frames per second in a semi-forward scattering direction. The illumination is close to the ejection source which means that the particles are sized before evaporation. The measurement can size stationary droplets from 3.4 to 44 µm and moving droplets from 4 to 80 µm resolved in both time and space. To get a reliable estimation, careful calibration of scattering angles and calibration uncertainty has been performed showing a general uncertainty of 8%. Thus, the approach proposed in this article can provide valuable and accurate data to improve the understanding of the airborne transmission pathway. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/27b0d267-0961-44c7-ac8e-93869f482cc0
- author
- Roth, Adrian LU ; Frantz, David LU ; Stiti, Mehdi LU and Berrocal, Edouard LU
- organization
- publishing date
- 2023
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Lorenz–Mie scattering, Respiratory droplets, Particle sizing, High-speed imaging
- in
- Journal of Aerosol Science
- volume
- 174
- pages
- 17 pages
- publisher
- Elsevier
- external identifiers
-
- scopus:85171425740
- ISSN
- 0021-8502
- DOI
- 10.1016/j.jaerosci.2023.106257
- project
- High-speed 3D imaging of liquid jets, surfaces and respiratory droplets
- language
- English
- LU publication?
- yes
- id
- 27b0d267-0961-44c7-ac8e-93869f482cc0
- date added to LUP
- 2023-09-19 10:42:02
- date last changed
- 2023-11-07 10:37:17
@article{27b0d267-0961-44c7-ac8e-93869f482cc0,
abstract = {{The COVID-19 pandemic has illuminated the lack of knowledge regarding the airborne transmission pathway of disease. The pathway consists of pathogens contained in small particles ejected when speaking and coughing. A crucial characteristic of these particles is their size that is connected to the their suspension longevity in the air as well as the location of generation and deposition within a subject’s respiratory system. Sizing of particles launched from the respiratory system is a challenge for a number of reasons: (1) the size of ejected particles varies over a wide range, between sub- to several hundreds of microns, (2) particles are ejected at various speeds in different directions, (3) each single event is unique where for example the number of particles can vary greatly between two occurrences of the same event and subject, (4) the size of the particles vary significantly as they evaporate over time. To overcome these challenges and categorize full coughing and speaking events, new measuring methods are needed. In this work, we present, in detail, high-speed scattered light imaging to size liquid particles (droplets) in unique respiratory events. A high-speed camera records scattered laser light at 16 000 frames per second in a semi-forward scattering direction. The illumination is close to the ejection source which means that the particles are sized before evaporation. The measurement can size stationary droplets from 3.4 to 44 µm and moving droplets from 4 to 80 µm resolved in both time and space. To get a reliable estimation, careful calibration of scattering angles and calibration uncertainty has been performed showing a general uncertainty of 8%. Thus, the approach proposed in this article can provide valuable and accurate data to improve the understanding of the airborne transmission pathway.}},
author = {{Roth, Adrian and Frantz, David and Stiti, Mehdi and Berrocal, Edouard}},
issn = {{0021-8502}},
keywords = {{Lorenz–Mie scattering; Respiratory droplets; Particle sizing; High-speed imaging}},
language = {{eng}},
publisher = {{Elsevier}},
series = {{Journal of Aerosol Science}},
title = {{High-speed scattered-light imaging for sizing respiratory droplets}},
url = {{https://lup.lub.lu.se/search/files/158926125/Roth_et_al._2023_High_speed_scattered_light_imaging_for_sizing_resp.pdf}},
doi = {{10.1016/j.jaerosci.2023.106257}},
volume = {{174}},
year = {{2023}},
}