Part 1: Main face mask FAQs
Part 2: More face mask FAQs
Part 5: A look at the face mask literature – written, going up soon
Appendix A: A short guide to the units of measurement
If you are pressed for time, just read Part 1.
I am providing this material for free, but it’s the result of a lot of full-time work. I don’t have a day job, or any income other than what I get as a writer, so please support me (see sidebar).
Note that many images can be clicked to enlarge, so if an image is a bit small to read, try clicking it.
If you have any comments, corrections, suggestions, that you wish to send me, use my email in the Contact section. (Trolls will be ignored.)