Much discussion lately in aerosol/disease transmission communities about the “5 micron cutoff” where droplets supposedly fall to ground w/in 1-2 m. @jljcolorado and @linseymarr has suggested ~50 microns.
Here’s some video evidence for that. 50 micron droplets wafting in lab...
Here’s some video evidence for that. 50 micron droplets wafting in lab...
Mind you, I’ve arranged my lab to minimize air currents, and they still easily float around (without a propeller: imagine that). It doesn’t take much convention to elevate picoliters of volume. Imagine a typical indoor environment with doors opening and people talking...
I know the size by electrostatically trapping the droplets and sizing them. 48 microns in diameter.
It’s time for med community to adjust what they think they know about aerosol and droplet transport.
It’s time for med community to adjust what they think they know about aerosol and droplet transport.
Obviously, I didn’t track these droplets across 1-2 m, but if they float like this over short scales in an area designed to minimize air flow, it doesn’t take much imagination to realize they will be carried farther than 1-2 m (and @CorsIAQ has posted calcs to show this, also).
(Apologies for terrible video quality, but my phone camera is the only camera I have setup for imagine on macroscopic scales.)
The number of typos in this thread are embarrassing, but it seems people can still make sense of the overall intent.
