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At the beginning of the Covid pandemic I remember the utterly surreal experience of walking into a bank wearing a mask. It was surreal because no one reacted, I was not immediately confronted by an armed guard, and no one called the police.
Why did it feel surreal to me? Some states and cities in the United States have had laws prohibiting the wearing of face coverings in public. It’s illegal. Some of these laws have been on the books for 150 years. In the U.S.A. I’ve always just assumed that face coverings, masks, burqhas, etc. are illegal unless I learn otherwise. Wearing a mask in a bank is just asking for trouble.
In New York, it’s been illegal since 1845 for a gathering of two or more people in public to wear face coverings. What about the Ku Klux Klan? The KKK arranges for a court to temporarily lift the ban for their demonstrations and then re-instate the ban. Halloween masks are, apparently, ignored. Face coverings have been illegal since 1949 in Alabama. California had stringent anti-mask laws going way back. These laws were struck down by the court after the State of California was sued by Iranian-Americans in 1979. DC prohibits masks in public after 10 PM. There are many other examples.
What’s going to happen when the Covid-19 Emergency Declaration ends on May 11th? We’re still losing 500 people a day to Covid.
High-performance masks are made to a specification that significantly exceeds the filtration efficiency of industry standard N95 masks. They deliver twice the filtration efficiency, and on particles down to 10 nanometers, which exceeds NIOSH N95 requirements by a factor of ten. All masks are equipped with a robust non-springy nose wire that can be shaped to seal to your face and nose.
If you want a reusable mask that looks nice and outperforms industry standard masks, you have found it here. They look the same as the standard masks but weigh slightly more because they contain three layers.
How do these masks work? In April of 2020, six researchers decided to collect samples of numerous fabrics used to make reusable masks and measure their filtration efficiency with the same equipment used to test industry standard masks like the N95. Since the topic here is viruses, the researchers enhanced the testing setup with a particle generator producing particles down to just 10 nanometers in size, making the test exceptionally demanding. (A Covid-19 virus ranges from 80 to 100 nanometers in size.)
Cotton, flannel, silk, and other materials were tested at 1, 2, and 4 layers, and then in various combinations. The researchers expected a cotton/silk combination to perform the best because of the electrostatic interaction between the two materials. Cotton/silk showed 92 percent efficiency. Howver, the researchers discovered that cotton plus 90/10 chiffon performed even better, reaching 97 to 98 percent efficiency.
This work appears in a peer reviewed scientific paper published by the American Chemical Society here:
The Covid-19 pandemic has kept me plenty busy. I apologize for not posting more often. One thing that’s kept me very busy is the making of masks, which are available on eBay.
These are top-quality masks with a comfortable muslin inner liner and outer material of high density cotton in various styles. Ear bands are comfortable 1/4-inch elastic.
Masks are equipped with a 6-inch wide padded annealed copper nose wire to conform the mask to the shape of your nose and face. This stops leakage and fogging of eyeglasses, and improves filtration effectiveness.