For the group that believes a second freezing is necessary, is it because of how some insects can apparently create some sort of internal antifreeze like material that can allow them to come back to life after being frozen? The second freeze then kind of "catches them by surprise" in a way as they are unthawing thinking "winter is over". (Is that the general theory?)
I have been told that as long as the freezer temp is already at -30 when the object is placed inside, the rate that the object cools down is rapid enough to prevent insects from protecting themselves with the antifreeze. Hypothetically, if you are freezing wood that is pretty thick/dense, and wood boring beetles had burrowed deep into the object near the center, could the thickness of the wood give those insects near the center a little extra time to protect themselves? Would this type of scenario benefit from a "double freeze"? -Todd On Fri, May 3, 2019 at 9:29 AM Voron, Joel <[email protected]> wrote: > At -30 for 72 hours once is sufficient to kill all life stages of pests. > JTV > > > > > > Joel Voron Colonial Williamsburg Foundation > > Conservation Dept. > > Integrated Pest Management > > Office 757-220-7080 > > Cell 757-634-1175 > > E-Mail [email protected] > > > > > > > On May 3, 2019, at 8:52 AM, Adrian Doyle <[email protected]> wrote: > > Dear all > > Double freezing shouldn’t be necessary so long as the core temperature of > the object is at the correct temperature for the correct time > > Adie > > > > Mr Adrian (Adie) Doyle > > Integrated Pest Management Manager > > British Museum > > Property & Facilities Management > > Great Russell Street, > > London WC1B 3DG > > > > Tel: 020 7323 8207 > > Mobile 07813 363292 > > Also available by Radio > > > > Email: [email protected] > > > > *The British Museum* > > Great Russell Street, London WC1B 3DG > > britishmuseum.org <http://www.britishmuseum.org/> > > > > *The security classification for this message is OFFICIAL* > > > > > > > > > > *From:* [email protected] [mailto:[email protected] > <[email protected]>] *On Behalf Of *Sharon Penton > *Sent:* 03 May 2019 13:51 > *To:* [email protected] > *Subject:* [pestlist] Freeze once or freeze twice? > > > > Good morning all, > > > > Some of my colleagues are adamant about freezing collection twice when > dealing with pest. They freeze a first time then let everything get back to > room temperature for a day or so then freeze again. Is this common > practice? I've always thought if we can achieve a reliable -30 that should > take care of all adults larvae and eggs? > > Would someone mind weighing in? > > Thanks! > > Sharon > > -- > You received this message because you are subscribed to the Google Groups > "Museumpests" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at https://groups.google.com/group/pestlist. > To view this discussion on the web visit > https://groups.google.com/d/msgid/pestlist/CALWceqtcq04tuBmBQP0uvpFfmNezUsXoCdFkWH4YMc%3DDYTP3KQ%40mail.gmail.com > <https://groups.google.com/d/msgid/pestlist/CALWceqtcq04tuBmBQP0uvpFfmNezUsXoCdFkWH4YMc%3DDYTP3KQ%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > For more options, visit https://groups.google.com/d/optout. > > -- > You received this message because you are subscribed to the Google Groups > "Museumpests" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at https://groups.google.com/group/pestlist. > To view this discussion on the web visit > https://groups.google.com/d/msgid/pestlist/DB6PR0201MB238959630E1D44BF3297289EDD350%40DB6PR0201MB2389.eurprd02.prod.outlook.com > <https://groups.google.com/d/msgid/pestlist/DB6PR0201MB238959630E1D44BF3297289EDD350%40DB6PR0201MB2389.eurprd02.prod.outlook.com?utm_medium=email&utm_source=footer> > . > For more options, visit https://groups.google.com/d/optout. > > -- > You received this message because you are subscribed to the Google Groups > "Museumpests" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at https://groups.google.com/group/pestlist. > To view this discussion on the web visit > https://groups.google.com/d/msgid/pestlist/9C51E7E8-C337-46D1-BE8C-A7CF7F7220DE%40cwf.org > <https://groups.google.com/d/msgid/pestlist/9C51E7E8-C337-46D1-BE8C-A7CF7F7220DE%40cwf.org?utm_medium=email&utm_source=footer> > . > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "Museumpests" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/pestlist. To view this discussion on the web visit https://groups.google.com/d/msgid/pestlist/CAMxAh%2BgsmkWXSMXcUqf6yDpe15ikTX2Kg1oxUodbU5xykxbXFQ%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
