Airborne transmission during short-term events under stratum ventilation

Kaho Hashimoto*, Zhengtao Ai, Arsen Krikor Melikov

*Corresponding author for this work

    Research output: Contribution to journalConference articleResearchpeer-review

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    Past studies on airborne spread of expiratory droplet nuclei between occupants were focused on long-term exposure under steady-state conditions. However, exposure during short-term events can be widely found in practice, e.g. medical examination or short meeting. Airborne transmission during short-term events under stratum ventilation was examined experimentally in this study. Two breathing thermal manikins were employed to simulate a standing infected person and a standing exposed person. The manikins were placed face-to-face and face-to-back to reproduce the exposure conditions with the highest and the lowest risk, respectively. Tracer gas was dosed into the air exhaled by the “infected” manikin to simulate the droplet nuclei. A newly developed average exposure index was used to evaluate the exposure risk. The time-averaged exposure index increases over time, but the increasing rate depends strongly on the duration of exposure time, e.g., the exposure index increases much faster during the first 5 minutes than during the period after 5 minutes. The exposure index during short-term events does not always decrease with the increase of separation distance. These findings imply that the control measures formulated based on steady-state conditions are not necessarily effective to short-term events.
    Original languageEnglish
    Article number01098
    JournalE3S Web of Conferences
    Number of pages5
    Publication statusPublished - 2019
    EventClima 2019: 13th REHVA World Congress - Bucharest, Romania
    Duration: 26 May 201929 May 2019
    Conference number: 13


    ConferenceClima 2019: 13th REHVA World Congress


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