Autoclave Procedure

Wear personal protective equipment:

  • Lab coat
  • Eye protection
  • Closed-toe shoes
  • Heat-resistant gloves to remove items, especially hot glassware

Packaging and Loading

  • Only designated individuals should be allowed to set and/or change parameters for the autoclaves.
  • Before using the autoclave, check inside for any items left by the previous user that could pose a hazard.
  • Clean the drain strainer before loading the autoclave.
  • Always place items in a secondary container.
  • Do not overload or package bags too tightly. Leave sufficient room for steam circulation. If necessary, place container on its side to maximize steam penetration and avoid entrapment of air.
  • Use only autoclavable bags to package waste.
  • Do not allow bags to touch the interior walls of the autoclave to avoid melting of plastic.
  • Ensure sufficient liquid is packed with contents of autoclave bags if dry.
  • Place soiled glassware and lab ware in secondary containers and autoclave them in the solids cycle. Do not fill containers more than 2/3 full with liquids. Loosen caps or use vented closures.
  • In case of clean glassware and wrapped instruments, lay them in a secondary container before autoclaving in wrapped goods cycle.
  • For secondary containment, use autoclave trays made out of polypropylene, polycarbonate or stainless steel. The trays should have a solid bottom and sides to contain the contents and catch spills.
  • Choose appropriate cycle for the material.  Incorrect selection of cycle may damage the autoclave, cause liquid to boil over or bottles to break.
  • Start your cycle and fill out the autoclave user log.  A completed cycle usually takes between 1 to 1.5 hours.
  • Check chamber/jacket pressure gauge for minimum pressure of 20 pounds per square inch (psi).
  • Close and lock door.
  • Check temperature for 250⁰F (121⁰C) every load.
  • Do not attempt to open the door while autoclave is operating.


  • Ensure cycle has completed and both temperature and pressure have returned to a safe range.
  • Wear PPE described above, plus an apron and face shield if removing liquids.  Stand back from the door as a precaution and carefully open door no more than 1 inch. This will release residual steam and allow pressure within liquids and containers to normalize.
  • Allow the autoclaved load to stand for 10 minutes in the chamber. This will allow steam to clear and trapped air to escape from hot liquids, reducing risk to operator.
  • Do not agitate containers of super-heated liquids or remove caps before unloading.
  • Place liquids in an area which clearly indicates the items are “hot” until the items cool to room temp.
  • Allow autoclaved materials to cool to room temperature before transporting. Never transport superheated materials.
  • Place cooled autoclaved biohazard bag into regulated medical waste box.  Autoclaved infectious liquids may be disposed of into the sanitary sewer.