UNDERSTANDING HEPA FILTERS IN AIR PURIFIERS

Nowadays, when choosing an air purifier for their home, customers often opt for models that use HEPA filters. So, what is the structure of a HEPA filter in an air purifier, what is its operating principle, and what are the appropriate steps for cleaning it? Let's join us in finding out in the article below!

1. WHAT IS A HEPA FILTER IN AN AIR PURIFIER?

HEPA stands for "High Efficiency Particulate Air," researched and developed by the United States Department of Energy (DOE) since the 1940s. Current popular HEPA filters are capable of filtering 99.95% according to European standards, and 99.97% according to U.S. standards, of fine and ultra-fine dust, pollen, viruses, or bacteria with a size of 0.3 micrometers or larger, and can filter a portion of dust particles as small as 0.01 micrometers.

HEPA filters were commercialized in the 1950s and have become a general term as well as a common standard for high-efficiency air filters today.

2. STRUCTURE OF THE HEPA FILTER

The HEPA filter is constructed from many glass fibers with sizes ranging from 0.5 - 2 micrometers, arranged randomly and interlaced, and pressed tightly to form a filter mesh with ultra-small gaps.

With such small gap sizes, dust and pathogenic particles in the air are easily trapped by the filter as they pass through.

3. OPERATING PRINCIPLE OF THE HEPA FILTER

The HEPA filter works quite simply; air containing dust and bacteria is first drawn in and comes into contact with the pre-filter, where large dust particles or pet hair are trapped, then the air proceeds to the main filter layer, which is the HEPA filter. At the HEPA filter layer, air containing fine dust and bacteria moves continuously and constantly collides with the glass fibers that are arranged randomly and tightly packed together.

The higher the rating of a HEPA filter, the more effective its air filtration capability. The HEPA E10 filter offers 85% filtration efficiency for airborne dust particles as small as 0.3 micrometers; the most popular today is the HEPA H13 filter, which removes 99.95% - 99.97% of fine to ultra-fine dust, and Acerpure products are also integrated with this filter; the HEPA U17 filter is the highest current standard, providing up to 99.999995% filtration of dust particles, however, this standard is only applied to evaluate products used for military and medical purposes.

4. HOW TO CLEAN THE HEPA FILTER

Step 1: Turn off the device and unplug it.

Step 2: Remove the filter cover; depending on each model, the method of removing the cover may vary (please refer to the user manual of each Acerpure product line).

Step 3: Use a vacuum cleaner or a dry cloth to wipe the dust off the pre-filter layer. Note: Do not use a wet cloth or water to clean the HEPA filter, as it may damage the filter.

Step 4: Reinstall the filter cover to its original position.