WHY A HEPA FILTER?
HEPA (High Efficiency Particulate Arrestance) filters are used in hospitals
because they are considered the best filters on the market today. Originally
developed by the Atomic Energy Commission during World War II to remove
radioactive dust which was invisible, but health hazardous, from the
manufacturing plant exhausts. A filter must collect 99.97% of a specific
particulate that measures 0.30 microns, in a test established by the Institute
of Environmental Sciences in order to receive the HEPA filter designation.
However, the HEPA filter can capture 100% of all particulate sizes ranging from
>100 microns down to 0.01 microns.
The HEPA media is made of very thin glass fibers. They are made into paper much
the same way as cellulose or wood fibers are used to make paper. In texture it
is very much like blotting paper, and air cannot pass easily through this dense
mass. A large area of paper must be used to permit the filtration of a large
volume of air. To get the large area it is pleated: hence the term: extended
Don't be fooled by "HEPA Type" Filters.
They may look like HEPA filters and be made of the same materials in the same
way, but the number and density of the fibers is reduced so that a larger
number of particles get through. This type of "HEPA" is available in
many different efficiency levels with the best being only about 95% effective
in capturing 0.30 micron size particles. This is well below the minimum capture
efficiency required of a true HEPA.
REMOVE THE CAUSES OF INDOOR AIR POLLUTION
While developing our air cleaner to work with any home heating/cooling system,
our engineers perfected a design that permits the use of a filter that meets
the HEPA standard, to capture the visible (above 40 microns), down the
invisible, (40 through 0.01microns) particulate found in indoor air.