Question from mammina
Dear Debra,
I am looking at some HEPA air filters and I have noticed that not all of them are certified HEPA. For example, the Austin Air Healthmate, which seems to be doing a good job at filtering chemicals, and is also more affordable, is not among the certified HEPA ones. What are you thoughts about this? Is it important to get a certified one, or the Austin would do the job?
Thanks a lot!
Debra’s Answer
HEPA stands for High Efficiency Particulate Air. HEPA filters are mats of randomly arranged fibers, typically made of fiberglass. Unlike other filter types, where particles as wide as the largest opening or distance between fibers cannot pass in between them at all, HEPA filters trap smaller particles by making them stick to the fibers of the mat.
HEPA filters, by definition, must remove at least 99.97% of airborne particles 0.3 micrometers in diameter. A certfied HEPA filter has been tested in an independent laboratory to verify the filter actually does meet this standard.
The original HEPA filter was designed in the 1940s. It was used to prevent the spread of airborne radioactive contaminants in the Manhattan Project. When HEPA filters were commercialized in the 1950s, “HEPA” became a registered trademark, but also a generic term for highly efficient filters, just as the trademark name “Kleenex” is a generic term for tissue paper and the tradmark name “Xerox” is a generic term for photocopies.
Filters that say they are “HEPA-type,” “HEPA-like,” “99% HEPA,” or simply “HEPA” do not meet the certified HEPA requirements and may not have been tested in independent laboratories.
Do you need a certified HEPA filter?
HEPA certification exists primarily for filters used in high technology industries–such as aerospace, pharmaceutical processing, hospitals, health care, nuclear fuels, nuclear power, and electronic microcircuitry (computer chips)–where particle-free air quality is required for manufacturing.
