Fluttershy, dressed in a blue surgical gown, light-blue surgical gloves, a light-blue surgical tail cover which covered her tail and a light blue surgical cap which covered her ears and the most of her hair except for the back, and is breathing in her white 8M 1870+ flatfold-style disposable particulate surgical respirator mask over her nose and mouth over her nose and mouth, to protect her from any harmful airbourne particles and nasty germs.
Fluttershy, like Twilight Sparkle, prefers this 8M 1870+ mask over the cup style masks, because it does a good fit on her.