The green stuff on a PCB

[skimask]

pre clean a length of solder with isoprop and then only handle and feed with lint free glove, my other glove is an unpowdered latex.

Exactly what they taught us in that school. You can clean the heck out of a board, clean the parts, perfect tips, and so on. Then a guy comes along and grabs that solder wire with his greasy hands and ruins everything. While I don't go as far as you do with the gloves, I do wipe down the last few inches of solder with iso before I use it.

Generally Medical, Military and Motor are exempt.

For that matter, on some things it seems like they're exempt from using solid state components...Tubes all of the place! Although I know the root reasons of why some boxes still use tubes. EMP comes to mind for one thing...