Filtration efficiency of face mask alternatives during the COVID-19 pandemic

[renate]

https://www.medscape.org/viewarticle/948263

I found this article on Medscape, but for those who don't have accounts, here are the relevant data. I was really surprised by how inefficient so many masks were. (The separate lines were bullet points under two headings in the original formatting, so I'm hoping that this doesn't break the four-paragraph rule.)

The N95 respirator achieved an FFE of 98.4%. The FFE of the other commercially available masks tested ranged from 79% to 26.5%:
3-layer cotton mask with ear loops = 26.5%
Polypropylene mask with fixed ear loops = 28.6%
Single-layer polyester gaiter/neck cover (balaclava bandana) = 37.8%
Single-layer polyester/nylon mask with ties = 39.3%
2-layer nylon mask with ear loops (without aluminum nose bridge) = 44.7%
Cotton bandana worn “bandit style” = 49%
Cotton bandana folded in a rectangle per Surgeon General’s recommendation = 49.9%
2-layer nylon mask with ear loops (with aluminum nose bridge) = 56.3%
Surgical mask with ties = 71.5%
2-layer nylon mask with ear loops (with aluminum nose bridge and 1 insert) = 74.4%
2-layer nylon mask with ear loops (with aluminum nose bridge and no insert; washed once) = 79%

In addition, the FFE for the standard medical procedure mask with ear loops were as follows:
No alteration = 38.5%
Loops tied and corners tucked back in = 60.3%
Secured with ear guard = 61.7%
Secured with 23-mm claw-style hair clip = 64.8%
Secured with 3 rubber bands to fix the mask = 78.2%
Secured with a 10-inch segment of nylon hosiery = 80.2%

[SheltieLover]

1. Ty!

[renate]

2. Sure!

I had read months ago that a three-layer cotton mask was one of the safer options (if the material was tightly woven), and have been feeling more safe than evidently I should have, so I wanted people who might have heard the same thing to know that it wasn’t actually all that protective.