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.
The N95 is made by various manufacturers under different names, from MSA's "Affinity Foldable Respirator" to 3M's "Particulate Respirator." Look for "NIOSH N95" on the package; the "N95" is a government efficiency rating that means the mask blocks about 95 percent of particles that are 0.3 microns in size or larger.
The N95 mask has a Particle Filtration Efficiency (PFE) of >95% @ 0.3 micron. Masks are intended for use in infection control practices. The P1 disposable dust respirators are suitable for protection against mechanically generated particles to 1 micron, such as dust and mist.
VFE, the maximum velocity at which the airplane can be flown with its flaps fully extended, is the high-speed limit of the white arc. Flying at speeds greater than VFE with full flaps can result in damage, perhaps to the point of losing one or both flaps.
ASTM F2100-11 Level 2. Surgical and Procedure Masks. Designed to resist ASTM Level 2 (moderate) protection from fluid strike-through, masks are available as either surgical masks with ties or procedure masks with earloops.
The efficiency of the filter can be calculated directly from the beta ratio because the percent capture efficiency is ((beta-1)/beta) x 100. A filter with a beta of 10 at five microns is thus said to be 90 percent efficient at removing particles five microns and larger.
ASTM F2299 / F2299M - 03(2017) ASTM International (ASTM) Title. "Standard Test Method for Determining the Initial Efficiency of Materials Used in Medical Face Masks to Penetration by Particulates Using Latex Spheres"
Bacterial Filtration Efficiency or BFE is a measurement of a respirator material's resistance to penetration of bacteria. Results are reported as percent efficiency and correlate with the ability of the fabric to resist bacterial penetration.
Level 2 masks are considered moderate barrier. Moderate barrier considers aerosols and splatter to be moderately generated. Level 3 masks are considered high barrier. This includes procedures where heavy amounts of fluid, splatter, and aerosols are produced.
EcoGuard Blue Level 3 Face Masks feature three-ply polypropylene construction that provides ≥99.9% BFE, and ≥99.5 PFE at 0.1μm. Meets ASTM Level 3 breathability and fluid-resistance standards.
No Difference in Influenza Prevention Via Use of N95 Respirator or Medical Mask. The use of N95 respirators vs medical masks among outpatient healthcare personnel resulted in no differences in incidence of laboratory-confirmed influenza.
Level 3 generally shows greater knowledge in a subject, and is often achieved in Years 12 and 13, or in centres for further education. Examples of Level 3 qualifications include: A level (grades A, B, C, D or E) Advanced subsidiary (AS) level.
Making the Comparisons between a certified Medical Mask & Disposable Masks. A Level 1 Disposable Medical Mask is ideal for scenarios where low amounts of fluid, spray and aerosol are produced. Level 2 are for procedures where moderate amounts are produced and Level 3 is for surgery.
American Society of Testing and Materials
Make sure the exterior (usually yellow or blue) side of the mask is facing out, away from your face. Place the mask on your face with the blue side facing out and the stiff, bendable edge at the top by your nose. If the mask has ear loops, put one loop around each ear.
