When picturing HEPA materials, you’re probably picturing something similar to an imaginary colander or screen. The materials in HEPA air purifiers actually do not look anything like that. Instead, they look like a very thin bail of fiberes, creating a veritible maze that the air has to find a route through, particle by particle. There are three different ways that HEPA filter air purifiers stop particulates. The easiest to understand is that a particle basically runs into a fiber and sticks. the second way is the particle getting within one diameter of a fiber in HEPA Air Purifiers and getting stuck on the fiber as it tries to skid by. Lastly, and the most complicated, is when very, very small particles (we’re talking 0.1 micron) travel in the gas flow, they sort of jump and juke due to the collisions with other molecules. This is called Brownian motion, and in itself can cause the molecules to be even more susceptible to the first two methods. To understand Brownian motion, picture bumper cars ramming into each other completely at random. Now picture the edges of the bumper car ring are actually sticky, or magnetic, holding the bumper cars to them. Now, to make things far more complicated, we’ll basically put edges all over the place so that the bumper cars have to navigate a treacherous maze. Only the other idiot bumper car drivers are still ramming each other, causing each other to get stuck, even if they would’ve skid through scot-free.

So you can see how HEPA air purifiers are capable of stopping bacteria, viruses, and mold spores, in addition to larger, more obvious items such as dust. For the most part, HEPA air filter purifiers can claim to be 99.97% efficient at removing the particles that are 0.3 microns from the air that passes through the HEPA air purifiers. The key word, though, is pass through. If the airflow doesn’t pass through the HEPA air purifieres, than it cannot be claimed. So, in essence, the claim of 99.97% is actually pretty inaccurate in those HEPA air purifiers that aren’t well designed, in which much of the airflow goes right around the HEPA air filters, and back into the room uncleaned. One series of HEPA air filters, the IQAir HealthPro series, is the only line that actually specifies that over 95% of air that enters their HEPA air purifiers goes through the actual HEPA filter.

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