Hi! Something I have heard that I've not seen mentioned.
We bag items to be frozen in plastic bags- usually they are paper based in record size boxes. For routine, precautionary freezing before going to storage we do not bag until just before freezing, as I have heard that insects can react to the change in atmosphere from bagging and prepare themselves to withstand freezing more easily. It is like they make antifreeze in response. We bag and load in less than an hour, not bagging too much at one time. I don't remember where I learned this. Has anybody else heard this? Randi Sue Smith Curator DC Booth Historic National Fish Hatchery and Archives US Fish and Wildlife Service 423 Hatchery Circle Spearfish, SD 57783 605-642-7730 ext. 215 fax 605-642-2336 http://dcbooth.fws.gov/ [email protected] Mary Baughman <m.c.boff...@mail .utexas.edu> To Sent by: [email protected] pestlist-ow...@mu cc seumpests.net Subject Re: [pestlist] Wrapping infested 06/10/2009 04:12 objects for freezing PM Please respond to pestl...@museumpe sts.net 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 [email protected] 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 [email protected] 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> <[email protected]> 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 [email protected] ------------------------------------------------------------- To send an email to the list, send your msg to [email protected] To unsubscribe from this list send an email to [email protected] and in the body put: "unsubscribe pestlist" Any problems email [email protected]
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