What is the difference between an N95 & N99 respirator?
The N95 designation means that the filter medium has a filtration efficiency of at least 95% (i.e. will allow no more than 5% particle penetration) against particles that are 0.3 microns in size. This means that up to 5 out of every 100 airborne particles can penetrate the filter medium and enter the wearer’s breathing zone. The N99 designation means that the filter medium has a filtration efficiency of at least 99% (i.e. will allow no more than 1% particle penetration) against particles that are 0.3 microns in size. This means that up to 1 out of every 100 airborne particles can penetrate the filter medium and enter the wearer’s breathing zone. It is important to note that while the filter itself will provide certain protection efficiency (95% or 99%) there are other potential sources of particle inward leakage of particles that can reduce a respirators effectiveness. These include: • Gaps between the respirator face piece and the face (the “face-seal”) • Exhalation valves • Holes fro
