Shooter McGavin said:
Thread killer. OP pull your head out
Spoiler : Masks-for-all for COVID-19 not based on sound data
Quotes from the article:
"The best filter tests use worst-case conditions: high flow rates (80 to 90 liters per minute [L/min]) with particle sizes in the least efficiency range. This guarantees that filter efficiency will be high at typical, lower flow rates for all particle sizes. Respirator filter certification tests use 84 L/min,
well above the typical 10 to 30 L/min breathing rates."
-Shot a big hole in their own study, me I don't plan on wearing one in a category 5 hurricane.
"Studies should also use well-characterized inert particles (
not biological, anthropogenic, or naturogenic ones)"
-Seriously, do I even need to explain how stupid this is.
"Filter efficiency was measured across a wide range of small particle sizes (0.02 to 1 m) at 33 and 99 L/min. N95 respirators had efficiencies greater than 95% (as expected). For the entire range of particles tested, t-shirts had
10% efficiency, scarves
10% to 20%, cloth masks
10% to 30%, sweatshirts
20% to 40%, and towels
40%."
-yikes, even using inert particles (unlike the sticky coronavirus covered in a sticky lipid & protein coating designed through evolution to help it stick to its victim) these materials still had some filter capabilities.
Note: the covid-19 virus I believe is 0.14 m (please correct me if I'm wrong).
The study above used inert particles in a size range from (
0.02 to 1 m)
If the size for covid-19 I gave above is correct the the efficiency of home made masks would increase.
Also note that as the n-95 respirator is worn, it loses efficiency over time while homemade cloth masks increased efficiency.