To help clean out your freezer, please follow these steps:

Check with your PI to see if you can clean out Freezers/Refrigerators.

Remove excess frost from freezer doors and shelves (or defrost if you haven’t performed your annual maintenance).

Vacuum coils and open the grill door to clean filter by vacuuming or rinsing in clean water (then let dry, replace filter)

Go through samples to determine what can be thrown out-see Priority Guidelines sheet for recommendations and always check with PI before throwing anything away. Check with other lab members as well.

Fill any open space left in freezer with frozen water jugs. This will reduce the amount of air the freezer must cool and extend the life of your compressor.

*Record how many times you fill up a paper box with discarded samples to measure volume


To gain well-organized samples please consider:

1.Please see Sample Inventorying page

2.Organizing samples by Experimental objective (e.g. molecule, biochemical pathway, organism).

3.Maintaining the correct samples in the right freezer. Everything does not need to be stored in an Ultralow, many things are fine in –20.

4.Stack boxes with labels facing forward

5. Consolidate samples where possible


Manufacturer’s Recommended Freezer Maintenance Schedule:

1. Quarterly de-icing door gaskets: check gaskets for punctures, tears, or leaks. Wipe with soft cloth.

2. Semi-annual filter cleaning: open grill, remove filter, rinse, dry and replace.

3. Annual Freezer Defrost:

• remove products and place in another freezer, turn off freezer

• leave doors open for 24 hours (put down cloths to absorb water)

• wipe out freezer and if there is odor, wash with baking soda/warm water solution

• close doors, restart freezer, once freezer reaches desired temperature, refill with samples

• check alarm battery yearly


LabRATS has a list of samples ranked in its value. This is helpful in determining what to get rid of. 

Here is an example table of how you may inventory your samples. A value of 10 is very valuable and a value of 1 is least valuable.

Sample Inventorying
Sample Descriptions Value 1-10
Unlabled 0
Expired Sample 1
Common Sample Date Unknown 1
Researcher Gone, Sample Unknown 1
Results Published, No Further Study Likely 1
Researcher gone, More then 3 years 1
Just In Case Samples, Saved As Backup But No Longer Needed 2
Short Term Samples 2
Researcher Gone, Valuable DNA Sample 2
Sample Redundant 2
Analysis Complete, Store Until Published 3
Researcher Gone, Still in Contact 3
Researcher Gone, Unprocessed Sample 3
Most Samples converted to RTSS 3
Raw Sample, Analysis Likely 4
Analysis Pending 5
Researcher Gone, Valuable Sample With Documentation Pending 6
Valuable Series of Samples, Potential for Retro Studies 6
Results Published, Likely Further Study 7
Irreplaceable or Moderatly Precious Sample 8
Irreplaceable And Extremely Precious For Ecological Work 9
Irreplaceable And Extremely Precious For Disease Control 10


LabRATS will be happy to offer assistance if you need it. Just let us know during the surveying process or Email us at