They may protect surgeons' faces from bodily fluids squirting out of the patient, but there's no definitive proof from any randomized, replicated, double blind clinical trial published in a peer-reviewed journal that they have ever prevented a patient from becoming infected.
They may protect surgeons' faces from bodily fluids squirting out of the patient, but there's no definitive proof from any randomized, replicated, double blind clinical trial published in a peer-reviewed journal that they have ever prevented a patient from becoming infected.
And, they have had over 100 years to fake it.