What is BFE and PFE?
BFE measures the filtration efficiency of a mask using viable (live) particles (bacteria) that vary in size from 1 to 5 microns. PFE measures the filtration efficiency of a mask using nonviable (nonliving) particles that are fixed in size from 0.1 micron to 1 micron.Similarly, what is BFE testing?Th...