Greetings -
I have just one observation to add:
One Friday afternoon we wrapped a book collection
in 3 mil thick plastic sheeting.
Each book was individually wrapped; the plastic
was wrapped closely around the book to eliminate
air space.
The truck to transport the large collection to a
commercial freezer was scheduled to arrive early
Monday morning.......
Monday morning we observed tiny holes bored
through the plastic by the "drugstore beetles"
(Stegobium paniceum) that we were attempting to exterminate.
I assume that the atmosphere inside the books
that had been sealed in the plastic was a little
too stuffy for the insects.
Mary Baughman
Book Conservator
Harry Ransom Humanities Research Center
The University of Texas at Austin
P.O.Drawer 7219
Austin, Texas 78713-7219
Telephone (512) 471-8635 or 471-9117
Fax (512) 471-7930
This is a message from the Pest Management Database List.
To post to this list send it as an email to pestlist@museumpests.net
To unsubscribe please look at the footer of this email.
-----------------------------------------------------------
Hi Alyssa,
Responding to your points:
1. To contain infestation while transporting specimen to the freezer
(Essential as it prevents spread, there may be quarantine time needed until
the freezer can be unloaded and the next load run through. yes, damage
continues in the bag at room temperature, but the overall level of control
of the crisis is greatly improved. I have several examples of large scale
pest treatments being sabotaged by poor quarantine during this phase.)
2. To prevent moisture content changes in the object during freezing, which
could result in dimensional changes and physical damage (Essential, as it
definitely does that by imposing a self-buffering regime)
3. To prevent damage from possible freezer failure (water drips/ floods,
debris from ceiling) (Essential as freezers *do fail*, and the
consequences are catastrophic if objects are not bagged, and the
consequences are more likely the more the freezer is used justifying its
purchase)
4. To prevent condensation from forming during its acclimatization before
the bag is opened (Essential for objects with surfaces likely to be
affected by condensation)
5. To prevent (or slow) re-infestation during acclimatization (Arguably
necessary. Tom Parker made a good point on the low reinfestation likelyhood
in the short term provided the acclimation place is not crawling. The point
I make is if you are reintroducing to collection, a reasonable use of the
bag you paid for in labour and material cost is a continued assurance of
protecting the object until the residual pest problem is solved (roving
critters, local sanitation, seal detail improvements etc). In dealing with
larger infestation problems, the acclimation space may only be in the
original resting space which you treat by residual spray, sanitation before
reintroduction of objects etc, in which case the bag is essential to reduce
contamination from the lower but still evident risk of reinfestation until
enough time has passed your trapping and inspection protocol lower your
evaluation of threat). Commonly the bag protects your investment in time
and labour - it does not represent a net loss in time and labour.
I am however interested in the discussion on necessity. In the thermal
treatment of some types of collections, taped coated cardboard boxes are
arguably sufficient for highly buffered, low mechanical risk objects, as
they act as a moisture barrier/buffer in the temperature transition phase.
We have used them in botany collection experiments and practices. But -
people then rely 100% on the freezer warning system and rapid staff
response should a breakdown occur.
Of course, sealable plastic containers are great, and are beautifully
matched to collections like natural history where size distributions are
dominated by handfuls to arm-sized specimens.
In general, the stipulation of the use of polyethylene bags is a wise one,
as failure occurs in batches in the freezer, not individual items. The
bigger the load, the greater the risk. The primary issue is reducing labour
and wastage costs through adopting reusables to handle common sizes.
Sincerely,
Tom Strang
Canadian Conservation Institute | Institut canadien de conservation
Senior Conservation Scientist | Scientifique principal en conservation
Institut Canadien de Conservation | Canadian Conservation Institute
Ottawa, Ontario, Canada, K1A 0M5
tom.str...@pch.gc.ca
Téléphone | Telephone 613-998-3721 (extension 239)
Télécopieur | Facsimile 613-998-4721
Téléimprimeur (sans frais) 1-888-997-3123 | Teletypewriter (toll-free)
1-888-997-3123
"Becker, Alyssa
TPCS"
<alyssa.bec...@go To
v.sk.ca> <pestlist@museumpests.net>
Sent by: cc
pestlist-ow...@mu
seumpests.net Subject
[pestlist] Wrapping infested
objects for freezing
06/03/2009 06:51
PM
Please respond to
pestl...@museumpe
sts.net
Hello,
Here at the Royal Saskatchewan Museum I wrap anything to be treated for
insect pest infestation in polyethylene plastic prior to freezing. These
objects are most often natural history specimens (mounts) and textiles or
leather/hide/feathered objects from our Aboriginal History collection.
Lately this practise has come into question - is it not a waste of time and
resources to do this, especially since much of the plastic must be thrown
away to prevent possible cross-contamination? Could the wrapping stage be
eliminated for adsorbent objects in good condition?
My reasons to continue wrapping are listed below. However, I wanted to pose
these questions to the list for thoughts, from a practical point of view,
as to whether wrapping is important, and if so, how and when. Has anyone
has come up with a more environmental alternative? For example, has anyone
found a line of vapour -proof, washable tubs that would do the same job for
a variety of sizes of mounts?
Reasons for wrapping:
1. To contain infestation while transporting specimen to the freezer
2. To prevent moisture content changes in the object during freezing, which
could result in dimensional changes and physical damage
3. To prevent damage from possible freezer failure (water drips/ floods,
debris from ceiling)
4. To prevent condensation from forming during its acclimatization before
the bag is opened
5. To prevent (or slow) re-infestation during acclimatization
Your thoughts and ideas on the subject would be most appreciated!
Sincerely,
Alyssa Becker
Conservator
Royal Saskatchewan Museum
2340 Albert Street
Regina, Saskatchewan S4P 2V7
P: 306-787-2667 F: 306-787-2645
alyssa.bec...@gov.sk.ca
-------------------------------------------------------------
To send an email to the list, send your msg to pestl...@museumpests.com
To unsubscribe from this list send an email to
imail...@zaks.net and in the body put:
"unsubscribe pestlist"
Any problems email l...@zaks.com
