Best Practices

• Inventory and label samples and post map of contents to front of freezer to reduce search time.
• Raise temperature set points from -80'C to -70'C to save energy and extend compressor life.
• Keep “back-up” ULT freezers at -50 or -60 degrees Celsius to save half the energy while being ready for emergencies. Establish alternate emergency plans such as having back-up CO2 tanks hooked up to the ULT or adding dry ice to maintain temperatures while waiting for the back-up ULT to get cold.
• Share refrigerator and freezer units with neighboring labs or consolidate and retire units within a lab. Have a plan in place for reducing the total number of ULTs.
• ULT’s generate significant waste heat. Purchase models that reject the least amount of heat and optimize the location of ULTs to reduce cooling loads. When supplemental cooling is available, consolidation may make sense; other times, dispersion may make more sense.
• When consolidating freezers, implement air management strategies such as paneling off the space behind the freezer to create a hot aisle and positioning exhaust vents above the back of the freezers to capture the rising hot air.
• Consider liquid nitrogen storage as an alternative to ultra-low freezers.
• Encourage efficient use of freezer space by using appropriately sized supplies, such as tubes, storage racks, and boxes, to store samples in.
• When possible use dry storage at room temperature instead of cold storage, or use products that allow storage of dehydrated DNA and RNA at room temperature without degradation.
• Install energy and temperature monitoring systems and implement a predictive maintenance strategy to identify distressed freezers and take early corrective action to prevent failures.