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What is a HEPA Filter?

What is a HEPA Filter?

Rensair remains the premier brand for top-of-the-line HEPA filters. However, not everyone is familiar with air-purifying terminology. So what exactly is a HEPA filter, and how is it different from other air filters?

“HEPA” is an acronym that stands for ​​”high efficiency particulate air,” which refers to the level of air purifying performed by a filter with this title. HEPA filters, commonly referred to as hospital-grade air purifiers, remove approximately 99.97% (but likely more) of dust, pollen, mold, bacteria, and other airborne particles (particulate matter) at a size of 0.3 micrometers or larger in diameter from the air. This measurement system takes into account that some particles, like dirt or smoke, are large enough (or dark enough in color) to be seen with the naked eye, while other particles are so small that seeing them requires a high-intensity microscope.


What does it mean for a filter to be HEPA?

While HEPA filters exist as their own category of air purifiers who can eliminate particulate matter to a certain degree (in comparison to EPA and ULPA filters), there are even more specific HEPA filter varieties. The type of HEPA filter—generally an H13 or H14—is dependent upon both the smallest-sized particle it can successfully remove from the air, as well as its efficiency at doing so. These specifications are standardized by the United States Department of Energy (DOE).


Particulate matter can often cause irritations, allergies, discomfort, and even illness when left unaddressed, which is why HEPA filters are so useful. By removing as many airborne particles as technologically possible, HEPA filters reduce and prevent the issues above while also ensuring a space circulates clean, healthy air. Rensair in particular uses HEPA 13 filters, and has a large airflow capacity for purifying air (up to 20,000 cubic feet per hour).


Do HEPA filters need to be replaced? If so, how often?

To optimize your air filter, it’s best to replace it regularly to remove any buildup of particles that have been cleaned from the air; A fresh filter means a new cycle of breathable air for your space. Different types of filters and purifiers have varying life cycles, but checking your HEPA filter every six months is an ideal marker to determine if your filter needs replacing. If you begin to notice clogging or odors, it’s best to replace your filter immediately. Rensair HEPA filters only need to be replaced after approximately 9,000 hours of use (or about one year of continuous air purifying), whereas most other air purifiers on the market require replacements every two-to-three months. Meaning, Rensair is one of the most efficient, cost-effective, and low-maintenance hospital-grade air purifier brands available.


Moreover, unlike other air filters that require you to take notice of when it is time to replace your filter, Rensair will alert you when it is time to change the HEPA filter. Plus, since Rensair is a comprehensive brand, you can order replacement HEPA filters directly from the Rensair website. Replacement is easy and outlined in the instruction manual that comes with every Rensair filter, but technicians are always available to provide assistance if needed.