HEPA Filters Learning Center
Air Purifiers America has conducted testing and research on several models of air purifiers and filters, using a specialty laser particle counter to measure the percentage of particles removed from the air. Here are the key fact you need to know about HEPA technology and its use in air purifier and HVAC filters.
Fast Facts about HEPA
High-Efficiency Particulate Air (HEPA) Filters are proven to be the most trusted filter technology on the market. The key to HEPA Filters is its tightly woven composition, making them an effective and safe solution to remove airborne particles that can aggravate:
- Athma attacks
- Chemical sensitivity
- Settling dust
- Mold growth
- Pet-related allergies and odor
- Smoke odor
- Illnesses linked to viruses & bacteria
- Long term respiratory health problems
How does HEPA work?
HEPA is a flat, pleated sheet composed of millions of microscopic fiberglass threads, forming a complex maze which traps airborne particles.
Because particles 0.3 microns are the weakest point of the filter's performance, a filter is only classified as HEPA if it removes 99.97% of particles that are 0.3 microns.
Three types of capture
As particles flow by, they are attracted and stick to nearby HEPA filter fibers.
Air flows smoothly around filter fibers, but particles collide and get embedded.
Microscopic particles move erratically, increasing the likelihood of being captured by interception or impaction.
How does HEPA compare to HVAC filtration?
HEPA filters have the highest level of filtering available. Most home HVAC systems are not designed to handle the strain of the high resistance filtering of a HEPA filter, so an HVAC filter with a tight weave may reduce air flow and ultimately lower air quality. HVAC filters come in different MERV ratings,but even the most efficient MERV-rated HVAC filter is less efficient than an HEPA air purifier. If HEPA filtration is required, we recommend an air purifier.