Autoclave

Summary

Autoclaving is the process of exposing material to intense heat and pressure to sterilize it of all living things. It is primarily used in microbial labs for two purposes: 1) ensuring the sterility of materials and media before use and 2) the serialization of contamination and cultures prior to disposal.

The three types of loads

  1. Dry Loads: these consist of glassware (including glass pipettes, glass beads, culture tubes, and small bottles for filter sterilized media) and autoclave-safe plastics, like stocked boxes of pipette tips and Eppendorf tubes. Everything that goes in a dry load is already clean, most of the items having already gone through a Waste Load and then washed. The dry load completely sterilizes these items so they can be used for culturing without fear of contamination.
Dry loads containing plastics (like tips) need to be removed from the autoclave within an hour or so of the cycle finishing. If they remain in the autoclave with the door shut for too long, the tips will warp and become unusable. The autoclave uses steam to sterilize things, so even after the dry time most of the glass and plastic ware will still be wet. Fortunately, there is a dryer down the hall on the right from the autoclave room on the 3rd floor of LSB where the load can dry for a few hours before being put away.
  1. Exposure Type: Wrapped
  2. Exposure Time: 30-40 minutes (depending on size of load)
  3. Dry Time: ~20min
  1. Media Loads: loads containing liquid media (in bottles) or agar media for petri dishes (in foil-covered flasks). Before you put the load in the caps on your bottles should be loosened to prevent a pressure differential from forming in the autoclave and breaking the glass. Set a timer for the load because it is very important that you go get it as soon as it is finished and tighten all the caps to prevent your media from becoming contaminated.
    1. Exposure Type: Liquid
    2. Exposure Time ~30min (small bottles) to ~50min (large flasks)
    3. Dry Time: NA
  2. Waste Loads: loads containing waste bags and/or contaminated glassware. Anything that touched live phage or bacteria must go through a waste load before it can be washed or disposed of. Antibiotic stocks and media must also go through a waste load prior to disposal, as this breaks down to antibiotics and prevents any germs in the sink from becoming superbugs!
    1. Exposure Type: Liquid
    2. Exposure Time ~45min
    3. Dry Time: NA

Autoclave Locations

  1. LSB 3rd floor (need to be trained by member of Kerr Lab)
  2. Hck 5th floor (need to be trained by Alex Hansen (email -> mailto:ahansen [snail] u [period] washington [period] edu)