Portable air filtration devices

How's this for "I-CAN'T-FIGURE-OUT-HOW-THIS-WORKS!" Our room
dehumidifiers finally gave up the ghost, ... at just the time a
snake-oil charmer of a traveling salesperson came through town peddling
portable air purifiers he claimed could also reduce relative humidity.
In a test, they were terribly efficient! ... really putting the best of
room dehumidifiers to shame.  So what's wrong in Eden (or Elam as the
case may be)?  WE CAN'T FIGURE OUT HOW THEY REDUCE HUMIDITY!"

We have a NSA Environmental Air Systems (4260 E. Raines Road, Memphis TN
38118) portable room air purifier. The 1200A series unit in test does
not SEEM to generate ozone.  It has EC1200 Tri-Media Filters.  (Other
units also have HEPA #High Efficiency Particulate Air# rated filters
sufficient to filter and neutralize mold spores).  The EC1200 Filter
looks and acts very much like a car's filter.  The motor does not
generate much heat & processes 36 cubic feet per minute.  (Other units
process up to 120 cfm.)

Sure, they purify air!  But does anyone know how they control humidity?
There is no condensation! Could it be as simple as a fan effect?

Erich J. Kesse
Preservation Office
University of Florida Libraries
904-392-6962
Fax: 904-392-7251

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                  Conservation DistList Instance 5:40
               Distributed: Wednesday, February 26, 1992
                        Message Id: cdl-5-40-012
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