E) N-95 isn't anywhere near 100% prevention of a corona virus but a whole lot better than nothing
Absolutely, but I didn't actually buy the masks for 2019-nCov, which I'm not afraid of. They are however the standard for these sorts of things (unless you want to spring for an N100). Or to put it another way, go google for "ebola hospital" in google images. The folks from the CDC show up in BSL4 space suits but the locals and Médecins Sans Frontières use whatever they can, and most of them live. They are however covered head to toe which you cover in your post.
If anything I would say that what people are missing in this 2019-nCov scare is eye protection, but I AM NOT an MD. Also, I have a beard which is my other big problem if I wanted to be protected.
D) the droplets containing virus particles that can infect people are orders of magnitude smaller than fibreglass particles
Not according the the link that I posted above which clearly states that fibreglasss particles can and do come in 1 micron dimensions while typical droplets that would actually be floating around in the air would be ~5 microns.
C) the bulk of corona viruses are actually transmitted through saliva droplets entering the infectee via the eyes or hands that go on to touch the infectee's face. Complete barrier nursing includes body suits, eye covers and gloves, as well as stringent washing.
I never said otherwise. I personally would fear for my lack of paying attention more than anything else.
B) your wife will have a well fitted mask which is a whole lot different from one purchased from a hardware store
Her lab stocks 3M part number 8271 if you want to look it up. Technically a P95 mask, but I doubt that I'll find much 2019-nCov floating around in oil. I would imagine that her biggest advantage is decades of training to not touch herself somewhere dumb, and knowing how to put the mask on right. Also, her biosafety cabinet but there's nothing I can do about that.
A) the vast majority of stuff your wife works with in the lab are not respiratory and transmitted person to person. Her mask is as much to prevent her messing up samples as it is to protect her
Absolutely, because then it would be BSL3, not BSL 2+. But to the best of my knowledge N95 still meets OHSA/NIH/CDC requirements for BSL3, whether or not her hospital would require something better. If you have any evidence to the contrary I would be very interested in seeing it. I didn't find a good BSL3 document with a few minutes of googling.
EDITed to add - a quick google showed someone saying that they wear a N95 mask for avian influenza research in the BSL3 lab at the University of Warsaw.
EDIT2: if you really wanted to you could read
this.