So during surgery the doctor doesn’t sneeze or accidentally transfer bodily fluids into the open wound..
THAT is why they wear those masks.
Most of us have known that for decades..
:-)
“So during surgery the doctor doesn’t sneeze or accidentally transfer bodily fluids into the open wound..”
Exactly.
Snot stoppers.
The pore size of a mask is so much larger than a virus. It’s like using a chain-link fence to stop a mosquito.