-80 degree freezer

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The average frost-free kitchen freezer maintains a temperature of about -15 C. A domestic chest-style deep freezer descends to perhaps -18 to -25 C. Although such freezers are also common in laboratories, many research applications require tissue extracts and specialized reagents to be stored at much lower temperatures. The universal standard for such ultra-low temperature units are those that can maintain a temperature down to  -80 C. (Materials having to be stored at still lower temperatures are stored submerged in liquid nitrogen, the boiling point of which is -195.80C.) Our laboratories have depended on a 13 cu ft -80 C freezer (Forma Bio-Freezer) that is now over 25 years old. Although still working, this -80 C freezer has had difficulties maintaining temperature below -75 C on occasions, and in recovering its temperature after opening the door for retrieving or adding samples. The fluctuation in temperature is detrimental for the stored materials. During a recent service call, we were informed that parts are no longer available for this unit, and that we are fortunate that it has lasted more than 15 years. Having a reliable -80 C freezer is vital to the ongoing research of the applicants' laboratories. Two of the six researchers intending to share the new freezer have joined our department recently. Hence we propose to replace the current freezer with one that is 24 cu ft.