What is a HEPA Filter and Why It's the Best Purifier for Your Facility

Are you in the market for new filters and wondering which option is best for your facility? A HEPA filter is the answer! HEPA is the filter of choice to keep dust out of high-risk environments, and has many advantages over other types of filters such as ULPA. In this blog post, we are going to explore the reasons why a HEPA filter is the best option for your facility. Let’s get started!

What is a HEPA Filter?

A HEPA filter is a type of pleated mechanical air filter. HEPA is an acronym, and the official definition of it from the U.S. Department of Energy is “high-efficiency particulate air [filter]”. This particular type of air filter can theoretically remove at least 99.97% of size 0.3 microns (µm) from the air, including dust, pollen, mold, bacteria, and any other airborne particles.

The size of 0.3 microns is the worst-case scenario, otherwise known as the most penetrating particle size (MPPS). Particles that are larger or smaller than 0.3 microns in diameter are trapped in the HEPA filter with higher efficiency. By using the worst-case particle size, the worst-case efficiency rating of 99.97% for all particle sizes is created.

A HEPA filter is made of complex interweaving glass and synthetic fibers. The glass fibers make up the acting part of the filter, and the synthetic fibers are the membrane. The fibers are packed incredibly tightly together to ensure that they filter the most contaminants possible. To give you an idea of how small 0.3 microns is, a human hair can be up to 100 microns in diameter.

What is a MERV Rating?

A Minimum Efficiency Reporting Value, or MERV, reports a filter’s ability to capture particles between 0.3 and 10 microns in size. This value is helpful if you are trying to compare the performance of different filters. Remember that the higher the MERV rating is, the better that filter is at trapping specific particle sizes. All HEPA filters have a MERV rating of seventeen or higher.

Why Should I Get a HEPA Filter?

Construction dust is full of harmful substances and chemicals, and even healthy people with robust immune systems can wind up being harmed by it. Depending on the type of facility you are working in, such as a doctor’s office or hospital, this dust can come in contact with people who are in a weakened state and could be made sicker. This is why there are such strict measures in place to protect both workers and patients during facility repair or construction projects.

Which Level of HEPA Filter Should I Purchase?

There are two different grades of HEPA filters: H13 and H14. Ignore any filters that use marketing terms such as “HEPA-like” or “True HEPA”, because these are not genuine HEPA filters and will not filter out microns properly. Also, be sure to look at the filtration level or the MERV rating of the filters you are purchasing. If the filtration level or MERV rating is not explicitly stated, you are definitely not looking at a HEPA filter.

An H13 filter adheres to the ISO and European Standard definition of HEPA, which is removal of 99.95% of 0.3 micron particles from the air. They are excellent filters, but they do not necessarily meet the ASME, EPA, or US DoE definition of HEPA. That task falls to the H14 filter, which removes at least 99.995% of 0.3 micron particles. While this might not sound impressive at first, the math checks out: if there are 10,000 construction particles you want to filter out, the H14 filter might let one particle through, while an H13 filter could let anywhere from three to five through.

To ensure you are doing everything possible to keep everyone safe and healthy, using HEPA filters is an essential step.