actually.. if said user places their face in between the two cups of the wearer, then that user gets twice the filtration and the wearer never has to take it off. A win-in my any book.
Science can do many things, like make a supercomputer for consumers in 15 years, but no engineer, or anyone, can make a proper one-size-fits-all bra. None. It. Cannot. Be. Done. Ever. Unless, just maybe, if you put a supercomputer INSIDE a bra!!! Hmmmmm...