What Is a Hepa Filter?

HEPA, which stands for High-Efficiency Particulate Air, is a type of pleated mechanical air filter that uses a fine mesh material to capture small particles. First invented back in WWII, the HEPA Filter was used by scientists to capture radioactive particles during the creation of the atomic bomb.

HEPA filters remove at least 99.97% of dust, pollen, mold bacteria, and any particle with a size of 0.3-micron. To give you an idea of how small .3-microns are, the average human hair is between 70 to 100 microns, and household dust is between .05 to 100 microns. 

So how do HEPA filters work? 

Most HEPA filters today are made from interlaced glass or ceramic fibers to create a fibrous maze. As particles make their way through this maze, they are trapped in four different ways.


Direct Impact: Large particles, bigger than .5 microns such as mold, pollen and, certain types of dust collide with the fiber and stick to it. 

Sieving: Airflow carries slightly smaller particles through two fibers, but the particle is bigger than the space causing the particle to stick to the fibers. 

Interception: If particles are not caught, they continue and catch to the sides of the fibers. 

Diffusion: The ultrafine particles that are so light they do not flow with air and move more erratically. This is when fibers are so close particles cannot move through and become lodge in between the fibers. 

If you’re looking for a cost-efficient and effective air filter a HEPA air purifier is a great option. MatrixAir offers several commercial air filtration units designed with medical-grade HEPA filters to make sure your indoor air has you breathing easy. 

Need assistance finding the right air filtration system for your space? Call us at (603) 863-7553 or contact us now. 

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