What is a HEPA filter and why is it important?

What is a HEPA filter and why is it important?
News | ClearAir Admin | 2023-05-12

When choosing an Air Purifier for your home or office, the element to look at is clearly the HEPA filter. The quality of the HEPA filter used by the Air Purifier is key, as it is the most important element in the filtration process, cleaning the air of particles that are harmful to health and releasing clean air.

But what are HEPA filters? How do they work? Why are they so effective against viruses, bacteria, and allergens? Here you will find everything you need to know.

What is a HEPA filter?
HEPA (High Efficiency Particulate Air) filters are filters with a great capacity to filter small particles (really tiny ones!). HEPA filters remove more than 99.9% of the particles from the air stream that passes through them. These particles can be allergens, viruses, bacteria, chemical compounds, dust and many more.

This is of great help for people with asthma, allergies or those who suffer from respiratory problems. These types of filters are becoming very important during the COVID-19 crisis by helping to reduce the virus indoors, thus reducing the spread of the virus.

How do HEPA filters work?
 Air Purifiers absorb air, pass the air through a series of filters (including the HEPA filter), and release clean air into the room. The filter is composed of a mesh of randomly placed fibers, which are usually layers of cellulose, synthetic fiber or glass fibers. These fibers are arranged in an accordion shape, which gives them a greater capacity to capture the particles. The HEPA filter easily removes pathogens larger than 0.3 microns.

HEPA filter efficiency
To choose between one Air Purifier or another, you need to know what type of HEPA filter each purifier uses. Therefore, you must start by knowing what percentage of particles the different types of HEPA filters are capable of holding.

The HEPA Filter must be certified
When choosing a HEPA filter, it is essential that it is certified. To be certified, HEPA filters and Air Purifiers must pass certain tests. In Europe, HEPA filters must remove at least 99.95% of particles from the air.

In Europe  HEPA filters are classified by the UNE-EN 1822-1: 2020 standard.


The True HEPA Filter (American classification) is the one used by WINIX in our Air Purifiers, it is between H13 and H14 (European classification), filtering 99.97% of the particles.

What is the True HEPA filter? 
The type of filter most used by WINIX air purifiers
In the US to be considered a True HEPA filter, a HEPA filter must be certified to remove 99.97% of all microscopic particles as small as 0.3 microns in size. 0.3 microns is the smallest particle size that enters the lungs. Microns, which are one millionth of a meter, are how particles are measured. It is impossible for the human eye to observe anything smaller than 10 microns.


Latest news