Saturday, April 24, 2021

New MIT guidelines on indoor airborne transmission

Vincent J. Curtis

24 Apr 21

A new peer-reviewed study released by M.I.T. professors and published in the Proceedings of the National Academy of Sciences provides great insight into the spread and the control of spread of COVID-19.

The paper is entitled, “A guideline to limit indoor airborne transmission of COVID-19.”

The authors are Martin Z. Bazant and John W.H. Bush, the former being professor of chemical engineering and applied mathematics, and the latter a professor of applied mathematics.  They applied what an engineer might recognize as the “stirred-flow tank reactor” model to the spread of the virus indoors, and the general results are therefore not surprising, given an element of dynamism to that model.

The results show that if locked in a room, no matter how large, with a contagious person, it is only a matter of time before an uninfected person takes in enough of the virus to become infected themselves.  Social distancing doesn’t matter, except as avoidance of being sneezed on.  Ordinary masking doesn’t help much if the time factor is indefinite.  Social distancing outdoors makes almost no sense, and that doing so with masks on is “kind of crazy.”  Ventilation slows the build-up of virus concentration in the room air.

The study shows why many lockdown measures are either useless or counterproductive, and there is no reason whatsoever to ban outdoors activities.  Problems arise when people are forced to stay indoors for prolonged periods of time in the presence of contagious persons.

The study provides guidelines that can be used by authorities inclined to employ lockdown measures.

-30-

No comments:

Post a Comment