ASHRAE Journal - July 2022 - 21

TECHNICAL FEATURE
of aerosols may indeed be steady state, the cabin is certainly
not well-mixed and the mass inhaled even over an
eight-hour fl ight is still only a fraction of that generated
by a cough.
The airfl ow patterns and high particulate removal
effi ciency in the aircraft cabin demonstrate the lack
of applicability of the well-mixed model assumption
(required for estimates made via the Wells-Riley formalism),
which is traditionally applied to buildings. From
the CFD model and the TRANSCOM study, low masses of
particulates are shown to spread from person to person
in airplane cabins.
Further information on these topics can be found in
https://doi.org/10.1101/2021.03.24.21254275
Acknowledgments
The authors would like to thank Robert Knapp for his
review and input, and Andrew Clark and Chao-Hsin
Lin for their CFD efforts. The authors thank the HighPerformance
Computing staff at Boeing who prioritized
access to computing resources for this activity and provided
around-the-clock server support. The authors
acknowledge Ansys™ for providing licenses for their
Fluent™ software to support Confi dent Travel Initiative
studies at Boeing. Finally, the authors thank the Boeing
technical writing staff for all their help in making this
paper more readable.
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https://www.doi.org/10.1038/s41598-02102663-8 https://www.doi.org/10.1038/s41598-02102663-8 https://www.doi.org/10.1371/journal.pone.0246916 https://www.doi.org/10.1101/2021.03.24.21254275 https://www.tinyurl.com/2p9atsvx https://doi.org/10.1186/1471-2466-12-11 https://doi.org/10.1186/1471-2466-12-11 https://tinyurl.com/2vttfn2r https://tinyurl.com/2vttfn2r http://www.shortridge.com http://ashrae.org

ASHRAE Journal - July 2022

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