When you are dealing with filtering viruses and bacteria from the air you want an air purifier with a medical-grade HEPA filter. Medical-grade refers to top tier H13 or H14 efficiency rated filters which will filter minimum 99.97% particles @ 0.3 microns (PM 0.3) or larger. These filters are relied upon in infection control isolation rooms and operating theaters. Made from a very fine pleated paper they maintain minimum efficiency at 99.95% or 99.995% @ 0.3 microns for the life of the filter. Most viruses are estimated to be 0.1- 0.125 microns in size. H13/H14 HEPA are effective in filtering approx. 95% or greater of particles @ 0.1 microns. The CDC recommends N95 masks for front line medical workers which filter 95% @ 0.3 microns to reduce exposure and chances of infection. The EOS is using H14 HEPA filter is much more effective than N95.
Why we don’t choose ULPA U17 to be the filter in the EOS?
The filtration result of ULPA is better than HEPA for sure, but on the other hand , the density of the fiberglass filter is also higher than a HEPA filter, so the suction will be weaker, because the wind resistance is higher, this will make the suction system with low efficiency. Secondly, the life of the ULPA is shorter than HEPA, because the density is higher so it is easy to be full, probably use half a year or shorter time , it need to be replaced. Thirdly, most of the surgical rooms in hospitals are using H14 HEPA filter, the result has been proven. Compare with all the reasons, H14 HEPA is the best choice for our suction system.