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Glossary Term
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Ethylene Oxide (EtO) Sterilization

Definition

Ethylene Oxide (EtO) Sterilization is a low-temperature sterilization method that uses ethylene oxide gas to eliminate microorganisms on medical devices and equipment. This process is widely used for sterilizing heat- and moisture-sensitive devices, ensuring sterility without compromising material integrity.

Relevance to the MedTech Industry

EtO Sterilization enables manufacturers to safely sterilize complex and heat-sensitive medical devices. It is essential for maintaining sterility and extending the usability of advanced materials and devices, particularly those with intricate designs or multiple components.

Additional Information & Related Terms

How EtO Sterilization Works


  1. Preconditioning Devices are exposed to controlled temperature and humidity to optimize the effectiveness of EtO gas.

  2. Sterilization Phase Ethylene oxide gas is introduced into a sealed chamber under specific temperature, pressure, and humidity conditions. The gas penetrates packaging and device materials, disrupting the DNA of microorganisms, rendering them non-viable.

  3. Aeration Sterilized devices undergo aeration to remove residual EtO gas, ensuring they are safe for use. This phase can take several hours to days, depending on the material and regulatory requirements.

Device Types Suitable for EtO Sterilization EtO is compatible with a broad range of medical devices, including:

  • Heat-Sensitive Equipment: Devices like catheters, sutures, and surgical instruments made from plastics or polymers that would degrade under high heat.

  • Complex Devices: Products with intricate designs, such as endoscopes or implantable devices, as EtO gas can penetrate small crevices and lumens.

  • Sterile Packaging: Pre-packaged sterile devices, as EtO gas can permeate through sealed packaging materials like Tyvek® or certain plastics.

Device Types Not Suitable for EtO Sterilization

  • Devices with Residual Toxicity Risks: Materials that retain EtO gas for extended periods may pose safety concerns.

  • Non-Gas-Permeable Materials: Products made of metals or tightly sealed items where gas penetration is inhibited.

  • Devices Susceptible to Gas Reactions: Certain materials, like polyurethane, may degrade or become discolored when exposed to EtO.

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