2024-04-08 15:25Press release

AAMI Releases Updated Guidance on EO Sterilization

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The Association for the Advancement of Medical Instrumentation today announces an update to one of its guidance documents on ethylene oxide (EO) sterilization.

Ethylene oxide usage is currently a pressing issue, with the medical device industry facing cost concerns and a regulatory landscape transformed by the recent Environmental Protection Agency rule that imposed emissions requirements.

This updated AAMI technical information report (TIR) provides a badly needed update to existing guidance on the microbiological aspects of ethylene oxide sterilization and includes information on the design and qualification for biological indicator or parametric release processes.

AAMI TIR16:2023; Microbiological aspects of ethylene oxide sterilization was produced by AAMI’s volunteer Industrial Ethylene Oxide Sterilization Working Group. The Working Group is co-chaired by Nicole McLees, global director of Sterility Assurance at Olympus and Ken Gordon, principal scientist, Innovation & Industry Representation, at STERIS Corporation.

TIR16 is an innovation, as it condenses relevant information previously available from multiple guidance documents into one resource. It also provides clarity on the use of process challenge devices (PCDs) for routine processing when biological indicator release is used. The new version of TIR16 is founded on best practices that have been successfully implemented in the United States.

Speaking to AAMI, McLees noted that the release of TIR16 is part of a greater international trend towards providing new guidance on methods other than the half cycle overkill sterilization method. “Actually the ethylene oxide standard ISO 11135 is being updated to include additional guidance on these methods.”

The updated version of TIR16 goes in-depth regarding process and equipment characterization including physical characteristics that impact the use of EO, including:

  • EO concentration
  • EO dwell time
  • Temperature
  • Humidity

Selection of the process definition method depends on many factors, which can include:

  • Product bioburden
  • Product design
  • Packaging
  • Load considerations
  • Manufacturing conditions
  • Sterilization equipment
  • Capacity

TIR16 also provides guidance on troubleshooting, sterilization loads, and the maintenance of product effectiveness.

Questions about the guidance document? Reach out to the AAMI Standards team at standards@aami.org. Are you a member of the trade press who would like a read-only copy? Reach out to dvisnovsky@aami.org.

About AAMI

AAMI (www.aami.org) is a nonprofit organization founded in 1967. It is a diverse community of more than 10,000 healthcare technology professionals united by one important mission—supporting the healthcare community in the development, management, and use of safe and effective health technology. AAMI is the primary source of consensus standards, both national and international, for the medical device industry, as well as practical information, support, and guidance for health technology and sterilization professionals.


Dan Visnovsky
Media Relations Manager
Dan Visnovsky
Your primary press contact for AAMI.