Science Seminars

The aerosol physics of SARS-CoV-2, which causes Coronavirus Disease 2019 (COVID-19)

Speaker: Brian Toon (LASP/ATOC)
Date: Thursday, Aug 20, 2020
Time: 4:00 PM
Location: Zoom

Seminar Abstract:

I will review what is known about transmission of the SARS-CoV-2. This review is not based on my original research, but on a review of the recent literature for a Fall class. Aerosol scientists think it is transmitted through micron sized particles that can remain airborne for substantial periods of time. The medical profession, largely based on information from the 1930s, thinks it is transmitted through large droplets with lifetimes of seconds in the air, an idea that was apparently debunked in the 1930s. In either case, masks made of almost any material will remove the virus. However, if air flows around the mask aerosols will not be removed.  Bandanas, for example, are not useful for protecting yourself against aerosols.  Social distancing, and any sort of mask is likely effective in outdoor settings.  However, indoors aerosols can build up over hour times scales.  It is particularly dangerous to be in a setting where people are singing, yelling or otherwise expelling a lot of air indoors. It is also possible that the virus can enter through the eyes. Indoors one is safest with a N95 mask, or similar tight- fitting mask. These are readily available, though there are many fakes on the market.  Safety glasses, that have foam or other sealants to keep air from the eyes are important.  It is also important to make sure the room air is being replaced with outdoor air frequently, or filtered with high quality filters. Using hand cleaners and wipes to clean surfaces is wise.