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Subject: Mold eradication

Mold eradication

From: Erich Kesse <erikess>
Date: Tuesday, January 7, 1992
Because UF has chosen to eradicate mold/mildew (M&M) utilizing means
other than fumigation, my experience will be of limited assistance. In
large part, we have not had to deal with recurrent infection.

1. Air Filtration Device.

This device probably cleans both internal/recirculated and external
(in-take) air, and most likely is intended to keep M&M spores from
entering from outside.  I believe that every library building in humid
climate zones should have such a device.  (Most UF libraries do not have
them yet.)  Filtration "standards" are suggested by Gary Thomas in his
MUSEUM ENVIRONMENT.  At very least, filters should be cleaned or
replaced regularly.

2. Ozone Generator.

Several ozone generator manufacturers are Florida based.  The device is
an effective M&M eradicator.  However, I have the following concerns:

(A) The effective range of the unit is limited.  It is like use of a
room dehumidifier in large library stacks or a quarter-sized magnet in
two ton stack of sewing needles.

(B) Generation of ozone may be harmful to library materials.  Though I
have not seen studies of its effects, I suspect that unless the storage
environment has sufficiently regulated relative humidity (RH) (and
possibly even appropriately regulated RH), oxygen/ozone enrichment may
result in or advance deterioration of library materials.

U.Florida is in the same situation as U.Hawaii in that our new HVAC
units also lack re-heat features (the result of low cost bidding and
insufficient inclusion of preservation concerns by facilities managers).
We have attempted to remove M&M spores present, prevent new spores from
entering and inhibit the growth of remaining or introduced spores.
These efforts include:

(a) chilling when necessary and possible (spores can not grow or are
inhibited by cold air) (this solution is attendant with use problems;
additional cooling during our humid winter months, for example, is not
widely appreciated);

(b) maintaining positive air pressure (which pushes air out when doors
are opened preventing incursion of spores);

(c) increasing air circulation (spores can not grow or are inhibited by
moving air);

(c) periodic rug cleaning with solution containing OPP (the chemical in

(d) dust eradication (spores collect in dust);

(e) food and drink control (foods may impart oils and other "surficants"

    **** Moderator's comments:   When the OED credits Erich with the
    coinage, one hopes they will spell DistList correctly.

which provide spores with a foot hold on materials);

(f) rebinding of volumes received with exposed rough (i.e., uncoated)
bookcloth fibers (fibers collect dust and provide spores with a foot
hold on materials) (rebinding process provides acrylic coated bookcloth
and trimmed text-block which is easily dry cleaned);

(g) aggressive M&M eradication treatments, many of which you probably
used, including: (1) vacuuming with lined, OPP treated bag and nozzle
attachment with attached OPP treated cheese-cloth filter (this should
result in dormancy of vacuumed spores and their retention in the bag),
and (2) dry cleaning followed by (3) limited aqueous cleaning with mild
OPP solution (@ 0.2% OPP).  This process is as labor intensive as

I regret to say there is no easy solution.

                   FAX: 904.392.7251.   TEL: 904.392.6962.

                  Conservation DistList Instance 5:35
                Distributed: Saturday, January 11, 1992
                        Message Id: cdl-5-35-006
Received on Tuesday, 7 January, 1992

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