4. Understanding aerosol/droplet behavior
Lydia Bourouiba, Ph.D + MIT Researcher
When it comes to understanding how aerosols travel through the air, the most extensive research has been conducted by Dr. Lydia Bourouiba at MIT. She has dedicated more than 10 years researching "expiratory events" aka sneezing, coughing and general exhalation/breathing and her conclusions are fascinating.
Through her research, we have learned:
• How aerosol/droplet clouds behave when being emitted from a person.
• Under the right conditions, liquid droplets can travel more than 26 feet and linger in the air for minutes.
• Liquid droplet clouds are likely to rise (not fall) because they tend to be warmer than the air temperature.
• Liquid droplet clouds can be pulled into air circulation systems.
Bourouiba has argued that the six foot guidance for safe social distancing is potentially flawed: “There is no virtual wall at this 3- to 6-feet distance. The cloud[droplets] can reach up to 26 feet for sneezes and less than that for coughs—about 16 to 19 feet.” Learn more about research studies by Lydia Bourouiba.
Think about pathogen bearing droplet clouds like train steam; an infected person walks around emitting trails of droplet clouds. If we are lucky, a breeze will disperse those clouds. However, if the spreader is unmasked and emitting clouds indoors, they can linger, rise and even get into the ventilation system. The last thing anyone wants to do is walk through those invisible clouds.
Bourouiba's studies have not yet entered into face shield effectiveness, but her research is helpful in illustrating how important it is to protect faces from lingering droplet clouds.
5. Dr. Fauci recommended shields to slow COVID-19 spread
"You should protect all mucosal surfaces."
In an ABC News Instagram Live on July 29th, 2020, Dr. Anthony Fauci said: "You have mucosa in the nose, mucosa in the mouth, but you also have mucosa in the eye. Theoretically, you should protect all the mucosal surfaces. If you have googles or an eye shield, you should use it."
What Dr. Fauci is saying is that your eyes are just as likely to come into contact with virus as your nose and mouth. It's important to protect all potential viral pathways.