Understanding Filtration Efficiency: PFE, BFE, and VFE

 

PFE represents the filtration efficiency of the filtration equipment for particulate matter in the air. Usually expressed as a percentage, for example, PFE 95% means that the device can filter out at least 95% of the particles. Particulate matter can be solid particles such as dust, pollen, dust, etc. The higher the PFE rating of the filter equipment, the better it is at filtering smaller particles.

 

The BFE test measures a filter's effectiveness against bacteria. Typically, bacterial filters are tested using bacterial aerosol particles ranging in size from 3 to 5 microns. BFE is expressed as a percentage and indicates the percentage of bacteria that the filter was able to block or capture under test conditions. For example, a mask with a BFE of 99% means that under test conditions, the mask is able to block 99% of germs.

 

The VFE test evaluates a filter's efficiency against viruses. Similar to BFE, VFE testing uses viral aerosol particles, which typically range in size from 0.02 to 0.3 microns. VFE is expressed as a percentage and represents the percentage of viruses that the filter was able to block or capture under test conditions. For example, a mask with a VFE of 98% means that under test conditions, the mask is able to block 98% of the virus.

 

It should be noted that the filtration efficiency indicated above was evaluated under laboratory conditions and does not fully reflect the effect in actual use. Filtration efficiency is also affected by a variety of factors, such as the materials used, the design and fit of the mask or filter equipment, etc. Therefore, when selecting suitable filtration equipment, all of the above factors should be taken into consideration and relevant guidelines and standards should be followed.