On 2010-08-04, Sam Takoy wrote:

Is this not a commonly available type of filters? Are they not
recommended for some reason? Can someone recommend an (online) place to
purchase them?

HEPA filters are very specialized and have absolutely no place in the
home. Basically, it's become the new marketing scam aimed at rubes.
HEPA filters filter such small particles, they are used in "clean
rooms", where micron sized particles are verboten. You have to build
a specialized room where outside ventilation is strictly controlled
and people wear clean-room bunny suits and the interior air is
constantly recycled through HEPA filtered whole and partial filtering
systems. Even the floors are part of the filtering system. The cost
of these rooms is staggering.

Anything claiming to be HEPA for your HVAC or vacuum cleaner is complete
nonsense.

nb