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Ethylene Oxide Processing

What is Ethylene Oxide Processing?

Ethylene oxide (also known as EO or EtO) is a low temperature gaseous process widely used to sterilize a variety of healthcare products, such as single-use medical devices. Through the use of a vacuum-based process, EO sterilization can efficiently penetrate surfaces of most medical devices and its lower temperature makes it an ideal process for a wide variety of materials.

What is Ethylene Oxide Processing?

Ethylene oxide sterilization uses a 3-part gas process which includes pre-conditioning, sterilization, and aeration. 

Ethylene oxide sterilization consists of four primary variables:

  • Gas concentration
  • Humidity
  • Temperature
  • Time

EO is an alkylating agent that disrupts cellular metabolism and reproductive processes of microorganisms. 

EO penetrates breathable packaging, making contact with all accessible surfaces of the product to deliver the required sterility assurance level (SAL).

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What are the Benefits of Ethylene Oxide Processing?

Ethylene oxide processing offers several key benefits, including:

  • Materials sterilized with EO are not exposed to excessive heat, moisture, or radiation. Therefore, a wide variation of materials, particularly polymeric components commonly used in medical devices, can be sterilized with EO. Material compatibility is described in AAMI TIR 17 (compatibility of materials subject to sterilization).
  • Products can be sterilized in their final packaging, since EO will permeate the sealed films and cartons used to package the device.

Standards:

Ethylene oxide sterilization is supported by the internationally recognized consensus standard, ISO 11135. 

This international standard outlines the requirement for the validation of an EO process to ensure that product processed through the validated process meets the required SAL. 

In addition, ethylene oxide processing is supported by ISO 10993-7. 

This international standard outlines trace levels of EO and ethylene chlorohydrin (ECH) may remain on products after an EO sterilization process. 

ISO10993-7 outlines the specific limits of EO and ECH that must not be exceeded in order to ensure product and patient safety. 

Data on meeting these limits is established during the validation of the EO process.

Ethylene Oxide Support Services:

In addition to ethylene oxide sterilization, STERIS AST provides our Customers with laboratory testing and technical support solutions at every stage of the sterilization design process, from product development through routine processing.

Our EO TechTeamTM guides Customers through the sterilization validation process, provides solutions for unique project needs, and supports Customers through their regulatory audits as needed. 

The EO TechTeam provides technical support for all matters relating to ethylene oxide, including (but not limited to): 

  • Technical consultation
  • Process development/optimization
  • Sterilization validation
  • Technical resources
  • General research and development

Our laboratory testing services provide Customers with:

Sustainable EOTM Sterilization Services

As part of our commitment to providing innovative and sustainable solutions, STERIS AST has developed the Sustainable EO sterilization services program.

Our Sustainable EO services provide Customers with strategies to reduce the EO sterilant used in the sterilization process to achieve the prescribed sterility assurance level. 

The program includes innovative approaches to EO sterilization, such as cycle design, validation strategy, and process challenge device design, all focused on the delivery of an efficient and effective process for sterilization of healthcare products. 

View our TechTeam resources to learn more about the ethylene oxide sterilization process.

What is Ethylene Oxide Used For?

EO is suitable for the sterilization of a wide range of materials not compatible with other methods of sterilization. Products commonly processed with ethylene oxide include:

  • Assembled complex devices
  • Catheters
  • Custom procedure packs
  • Equipment with integrated electronics
  • Multi-lumen tubing products
  • Stents
  • Wound care dressings
Catheters
ethyleneoxide
ETHYLENE OXIDE
Ethylene oxide sterilization uses a 3-part gas process which includes pre-conditioning, sterilization, and aeration

Technology Variables

  • EXPOSURE TIME
  • TEMPERATURE
  • HUMIDITY
  • EO CONCENTRATION
  • CHAMBER SIZE
  • SINGLE CHAMBER OR MULTI-CHAMBER
  • PROCESS PARAMETERS

Product Considerations

  • MATERIAL COMPATIBILITY
    • Very few compatibility concerns; liquids generally not recommended.
    • Packaging must be breathable
  • DENSITY
    • Higher density configurations may impact temperature distribution and processing time
  • TEMPERATURE
    • Processing conditions exposes product to heat, humidity, and pressure
  • GAS PATHWAY
    • Gas must reach surfaces requiring sterilization
  • CHARACTERIZATION OF NORMAL PRODUCT BIOBURDEN
    • Understanding the microbiological challenge of the product relevant for defining a sterilization process

Possible Effects

Trace levels of EO may remain on product after processing and product may require prolonged aeration to reduce to permissible levels

Exposure Time

  • HOURS TO DAYS
    • (depends on validation approach and time required for degassing)

Why Choose STERIS for Ethylene Oxide Sterilization?

With over 50 years of experience as a global leader, STERIS AST provides safe and effective ethylene oxide sterilization with comprehensive laboratory testing and technical support through every stage of the sterilization design process - from product development to routine processing.

  • Global Strength, Local Focus: Facilities across the Americas, Europe, Asia, and South Africa
  • Customer Experience: Continuous feedback to drive process improvements
  • Industry Leadership: TechTeamTM Technical Professional guidance through detailed and complex sterilization and laboratory testing processes
  • Technology-neutral: Radiation and gas technologies tailored to Customer needs
  • Excellence in Quality: Proactive approach to drive efficiencies, reduce rework, and improve quality
  • Innovative Technologies: Innovative offerings to support routine services and processing redundancy capacity
  • Service Commitment: Dedicated to timely routine processing and testing turn times
  • Business Investments: Upgraded equipment and quality systems, new locations, and expansions of existing facilities

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