I attended the online APS DFD meeting last week. There were a number of talks addressing aspects of COVID through the conference. Sunday morning had a "Mini Symposium on Infectious Diseases." It included a very good presentation by Howard Stone of Princeton, showing saliva threads between lips and vocal chords breaking up into droplets. He also showed a visualization of buoyancy effects in leakage around masks. Martin Bazant of MIT presented an analysis of indoor airborne transmission which seems very practical, A01:6: "A Guideline to Limit Indoor Airborne Transmission of COVID-19". The talk is available on his web site with a spread sheet. There also is a paper under review
The Bazant web site:
COVID-19 Indoor Safety Guideline------------------------------
Frank Chambers
Oklahoma State University-Stillwater
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