“A properly fitting surgical mask has the ability to reduce the viral load by 80%. A n-95 mask is shown to only reduce the load 90-95%. 10% difference.”
I’m glad we’re at least getting to the point here where people realize that you won’t get it by touching the same doorknob that an infected person touched a week ago, so that’s good (and hopefully I’m not putting words in your mouth). In other words, it’s viral loading (how much you get in a concentrated form, over a short period).
The math you’re using is a bit off, though. You have to look at the percent decrease in what gets through, rather than the percent increase in what gets stopped (i.e., “10% difference”). Because what gets through determines the viral loading you receive.
So, if you start with 100 particles, then 20 get through with a mask, and between 5 and 10 get through with an N95, so a drop of at least 50% with the N95, maybe 75% (based on your above numbers). So if you’re in a taxi with a vector and can breathe 10 minutes of his air without any mask and not get the virus, you’ll be able to breathe 50 minutes of his air with a regular mask, and 100 to 200 minutes of his air with an N95...and that is a big deal.
Agreed. The other factors though for the public is most people have no idea how to properly fit a n-95, how hard they are actually breathing in said mask, or how long that mask is actually good for.
The numbers came from one of the studies I looked at a few days ago their results were for a 15 minute exposure. And yes, a lot depends on the environment you are in. A closed in taxi with an ill person isn’t somewhere in an outbreak you want to be...even with a n-95 mask.
you’ll be able to breathe 50 minutes of taxi air, but after you get out of that taxi the virus is still embedded in the mask, and kept moist by your respiration. With a wellfitted mask, there is a drag on inhale. You will breath a bit heavier, which can suck that mask virus, which is only trapped in the middle layer, into your breath. (the outer layer being waterproofing, the inner layer being absorbent, with the middle layer as the trap layer). Maybe it would be a good idea to carry several masks and ziplocks so you can take off the mask you wore on the bus or subway or other crowded environ, stick it on the dash of the car or windowsill to bake in the sun, and put on a clean mask? Plenty of videos of poor Chinese villagers who had only been given one mask, and had been wearing it for a week or more, rather than be beaten. Concentrating virus every day.