This is a message from the Museumpests 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 all, We routinely treat collections with low temperature at minus 30 degrees C and have had no problems with unloading the freezer and allowing the collections items to come to room temperature - 24 hours minimum to be on the safe side (we do not use a refrigeration step.) Just make sure you keep them wrapped until they come to room temp so any condensation occurs on the wrapping not the object. Best, Emily
Emily Kaplan Conservator Smithsonian National Museum of the American Indian Cultural Resources Center 4220 Silver Hill Rd Suitland MD 20746 301.238.1418 fax 301.238.3201 kapl...@si.edu -----Original Message----- From: ad...@museumpests.net [mailto:ad...@museumpests.net] On Behalf Of Neil Carey Sent: Friday, August 24, 2012 11:19 AM To: pestlist@museumpests.net Subject: Re: [pestlist] Defrosting This is a message from the Museumpests 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 again, So then there is a need to bring objects back to room temp slowly. The rented freezer is getting picked up on Monday, so I'll need to unpack it on Sunday. There is a thermostat on it. I've had it cranked down all the way which has yielded -30c. I can gradually warm it up over time while keeping an eye on the temp. So, my question is, over how long a period is "Allow them to come up to the ambient temperature slowly?" 5 hours? 24 hours? Neil On Aug 24, 2012, at 10:40 AM, Anderson, Gretchen wrote: > This is a message from the Museumpests 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 Neil. > When you remove your package from the freezer, it is best to allow it come up > to ambient temperature as slowly as possible. This reduces the thermal shock > to the object. Ideally the object should be placed in a refrigerator until it > is thawed then move it to the room. I realize that this does not always > happen - it depends on your facilities. But the goal should be to bring the > objects up to room temperature as slowly as is feasible. > > You are creating a micro-environment to protect the item. If you have placed > your objects in a double layer well sealed plastic you will not have a > problem with condensation or see any evidence of localized relative humidity > on the piece when you remove it from the freezer. Allow them to come up to > the ambient temperature slowly and when they are completely acclimated you > can remove them from the plastic. You will not have a mold problem. > > It is a good idea to examine the object and maintain quarantine until you are > sure that the object is pest free. One way to do this is to keep it in a bag > for a while (length of time will depend on the life cycle of the pest > species). > > Anoxic is another topic. With this method you are actively removing the > oxygen from the bag or space around the object. There are advantages to this > method, and there are some things that are best stored and displayed in an > anoxic environment. But that is more complicated. For use of anoxia in pest > control , take a look at the various strategies on Museum Pest Net > http://www.museumpests.net/treatment.asp There is also a fact sheet on > bagging for isolation. > > Good luck! > Gretchen > > > > -----Original Message----- > From: ad...@museumpests.net [mailto:ad...@museumpests.net] On Behalf > Of Neil Carey > Sent: Thursday, August 23, 2012 8:50 PM > To: pestlist@museumpests.net > Subject: [pestlist] Defrosting > > This is a message from the Museumpests 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. > ----------------------------------------------------------- > Since implementing IPM a month ago, we've been successfully freezing our > ethnographic collection of mostly wooden African pieces, many with textile, > feather, or metal attachments, at -30c. Thanks to the group for all their > valuable input. > > However, I don't recall any discussion about controlling the defrost cycle. > Are there any special considerations? Off hand, I can think of the > possibility of mold growth if an object is kept double wrapped in > polyethylene after defrosting, despite being wrapped in tissue paper. Am I > overly paranoid? Just how long should a controlled defrost take? Must the > object be removed immediately? If not, how long can it go heat sealed in > bags? It's not like anoxic treatment where a piece can just be kept inside > its polypropylene bag forever. Any input? > > Neil Carey > > ---------------------------------------------------------------------- > To send an email to the list, send your msg to > pestlist@museumpests.Net > > To unsubscribe from this list send an email to pestlist@museumpests.net and > in the subject put: > "unsubscribe" - no quotes please. > > You are receiving the Pestlist emails in standard mode. > To change to the DIGEST mode send an > email to imail...@museumpests.net with this command in the body: > > set mode digest pestlist > > Any problems email l...@collectionpests.com or l...@zaks.com > > > The information contained in this message and/or attachments is intended only > for the person or entity to which it is addressed and may contain > confidential and/or privileged material. Any review, retransmission, > dissemination or other use of, or taking of any action in reliance upon, this > information by persons or entities other than the intended recipient is > prohibited. If you received this in error, please contact the sender and > delete the material from any system and destroy any copies. Any views > expressed in this message are those of the individual sender. > > > ---------------------------------------------------------------------- > To send an email to the list, send your msg to > pestlist@museumpests.Net > > To unsubscribe from this list send an email to pestlist@museumpests.net and > in the subject put: > "unsubscribe" - no quotes please. > > You are receiving the Pestlist emails in standard mode. > To change to the DIGEST mode send an > email to imail...@museumpests.net with this command in the body: > > set mode digest pestlist > > Any problems email l...@collectionpests.com or l...@zaks.com > ---------------------------------------------------------------------- To send an email to the list, send your msg to pestlist@museumpests.Net To unsubscribe from this list send an email to pestlist@museumpests.net and in the subject put: "unsubscribe" - no quotes please. You are receiving the Pestlist emails in standard mode. To change to the DIGEST mode send an email to imail...@museumpests.net with this command in the body: set mode digest pestlist Any problems email l...@collectionpests.com or l...@zaks.com ---------------------------------------------------------------------- To send an email to the list, send your msg to pestlist@museumpests.Net To unsubscribe from this list send an email to pestlist@museumpests.net and in the subject put: "unsubscribe" - no quotes please. You are receiving the Pestlist emails in standard mode. To change to the DIGEST mode send an email to imail...@museumpests.net with this command in the body: set mode digest pestlist Any problems email l...@collectionpests.com or l...@zaks.com
