The Latest Amendments to AAMI ST79

Did you know… AAMI’s ST79, Comprehensive Guide to steam sterilization and sterility assurance in health care facilities, is under a continuous maintenance process in order to keep this document current?

In 2008 and 2009, numerous amendments of the 2006 document were adopted.  These amendments addressed such topics as toxic anterior segment syndrome (TASS), paper−plastic pouches, steam quality, devices with lumens, chemical indicators, sterilization process failures, product families, evaluation of sterilization container systems, risk analysis, and verification of cleaning.

The second edition of ST79 published in 2010 includes the previous amendments, as well as additional changes in the provisions regarding steam quality, risk analysis, and a new section on new product evaluation.  The 2011 amendments, A2:2011 to the 2010 document put additional emphasis on the need to follow the manufacturers’ written instructions for use (IFU) and made a global wording change from hand washing to hand hygiene throughout the document.

Last November AAMI published the third amendment, A3:2012 of the ST:2010 book.  A3:2012 has numerous amendments.  Below are some of the latest amendment highlights:

  • The term sterile processing department is now referred to as sterile processing area to include those facilities that may not have a “department” such as ambulatory centers or dental offices.
    • Sterile processing area is defined as the area within a health care facility that processes and controls medical supplies, devices, and equipment, sterile and not sterile, for some or all patient care areas of the facility.
  • Flash sterilization was changed to immediate-use steam sterilization (IUSS) throughout the document. A new sentence states, “Sterilizing unwrapped items is not recommended”.
  • Dynamic-air removal cycles be used unless the device manufacturer only recommends a gravity cycle.
  • Language around loaner instrumentation recommendations was strengthened to include the need for additional time and space.
  • Shoe covers are recommended whenever there is potential for shoes becoming contaminated with blood or other bodily fluids.
  • Anti-fatigue mats should be used and should be cleaned regularly
  • Instruments should come to SP from the OR in an orderly fashion with sharps segregated and the delicate instruments on top and the heavy ones on the bottom.
  • Instruments requiring repair should be identified at the point of use.
  • Treated water (e.g., deionized, distilled, or RO water) is preferred for the final rinse since it prevents staining and contamination of instrumentation.
  • Decontam staff have ready access to the device manufacturer’s IFU.
  • Workstations should be ergonomic and preferably height adjustable.
  • A new section titled Break Out Area was introduced to include removing items from external shipping cartons, as shipping cartons may harbor and transport dust and debris that should not enter a sterile processing area.
  • The volume of water used in the cleaning sink or other cleaning container’s (e.g., transport bin, basin, etc.) should be calculated and appropriate dilution rates should be determined to ensure consistent and accurate cleaning chemistry use.
  • Dietary service items should never be processed in sterile processing areas.
  • A reminder was included to consider data drops and electronically needs.
  • A new Annex O was included in order to give a Comparison of the differences between AAMI and FDA classifications on chemical indicators.
  • Definitions for cavitations, free rinsing, impingement, nonporous, porous and sharps was added.


  1. ANSI/AAMI ST79:2010 & A1:2010 & A2:2011 & A3:2012 (Consolidated Text) Comprehensive guide to steam sterilization and sterility assurance in health care facilities
  2. Flynn, Susan.  Sterilization recommended practices. Checking in on 2012 updates. Available at:

Tags: , ,