08/11/2020
There's been many posts from various sources discussing a "study" measuring the efficacy of different types of face coverings. This has been embraced by those who have stridently opposed face coverings, particularly when recreating outside. So here's some things to consider:
First, If you are reading an article from CNN, Yahoo! Money, Business Insider, even the Washington Post etc. you are getting a predigested interpretation of a scientific study. A secondary resource (that is also mass media) does not suffice as scientific literature. Here's the actual study. It's not that hard to read: https://advances.sciencemag.org/content/early/2020/08/07/sciadv.abd3083
Second, let's look at the actual design of the study. We have a 30cm x 30cm Box (that's about 12 inches). A laser and cell phone camera (What??) are used to detect droplets emitted when someone speaks using different kinds of masks. What this study shows, at most, is that within a 12 inch x 12 inch box a buff or bandana (or T-shirt) does not provide protection from droplets. That only concerns 12 inches inside, not the recommended 6 feet. Remember, no mask mitigates the 6 foot requirement. Also, the degree of error involved, showed that sometimes they were worse and sometimes better and sometimes made no difference. They did not show that buffs/bandanas have no efficacy outdoors or at 3-6 feet. Additionally, they used various "speakers" repeating the sentence “Stay healthy, people”. They note that how the speakers mouth is positioned in the box and the velocity of speech all affect results. They note that using one cell phone camera has its limitations.
All this study suggests it that: a) more research needs to be done, and b) wearing a buff/bandana indoors, in close quarters is probably not adequate. But that had already been determined.
Six feet and a face covering still matters.
Mandates for mask use in public during the recent COVID-19 pandemic, worsened by global shortage of commercial supplies, have led to widespread use of homemade masks and mask alternatives. It is assumed that wearing such masks reduces the likelihood for an infected person to spread the disease, but....
