NIOSH N95 Masks $3 each

A NIOSH N95 respirator is a respiratory protective device designed to achieve a very close facial fit and very efficient filtration of airborne particles.  The NIOSH N95 is the most recognizable and effective mask. Its name means it can block at least 95 percent of tiny particles — 0.3 microns — that are the hardest to capture. An average human hair is about 70 to 100 microns wide.