Sterilization validation

Sterilization:
Validation and its Different Methods Explained

The validation of sterilization is an essential step, regardless of the technique chosen for treatment, that ensures the effective sterility of the products.

IONISOS, a specialized provider for over 50 years, presents the different processes based on the chosen sterilization technique.

3 Standards for Sterilization Validation

IONISOS specializes in industrial sterilization. We currently use three techniques in our treatment centers: beta and gamma sterilization (by radiation) and sterilization with ethylene oxide.

When you use our services, once the treatment technique is determined with the help of our experts to sterilize a product (medical device, packaging, etc.), it is necessary to establish the cycle parameters (for ethylene oxide) or define the method to be used to claim the sterility of the product and thus the minimum treatment dose in kGy.

This requires a multi-step validation process, determined by 3 different standards for the methods that interest us.

These texts encompass all the requirements regarding the development, validation, and control of a sterilization process.

The method chosen for the sterility validation of a product will vary depending on the sterilization technique used:

  • For beta or gamma treatment, the ISO 11137-2 standard (establishing the sterilization dose) or the ISO/TS 13004 standard (justification of the sterilization dose), sometimes referred to as the VDmaxSD method, will be applied.
  • For ethylene oxide treatment, the ISO 11135 standard will be followed.

For radiation treatment, the choice between the two methods will be determined by the microbial load of the product, as well as the maximum dose it can be subjected to without altering its characteristics.

The validation of ethylene oxide sterilization (or ETO) is based on a principle of overkill by half-cycle.

Treatment Validation Process

Discover here how the treatment validation unfolds step by step, for a validation on medical devices, for example.

Gamma or Beta Sterilization

The validation of radiation sterilization occurs in five steps:

1/ Maximum dose tests (to confirm the product’s tolerance)
2/Validation of microbiological analysis methods specific to the device for determining bioburden and conducting sterility tests
3/ Evaluation of the average initial bioburden
4/ Treatment of 10 samples at the verification dose, followed by conducting sterility tests on these samples

To validate the microbiological analysis methods according to ISO 11737, approximately thirty samples are required.

The measurement of microbial load will be performed on 30 non-sterile samples from 3 different production batches.

A verification dose will be calculated based on the average microbial load.

Finally, sterility tests allow us to guarantee the effective sterilization of products once the treatment is completed. The number of samples will vary depending on the standard followed.

Ethylene Oxide Sterilization

The validation of ETO sterilization occurs in three main steps:

1/ Installation qualification (QI): the purpose is to confirm that the logistics tool used complies with current standards.

2/ Operational qualification (QO): this demonstrates that the equipment is capable of applying the treatment while adhering to the defined cycle parameters (temperature, humidity, EO concentration, time, etc.).

3/ Performance qualification (QP): this attests to the consistency of the equipment in its operation to apply the predefined criteria, thus ensuring perfect sterility of the products. To achieve this, a minimum of three consecutive cycles must be executed for the process to be considered reproducible.

Various laboratory tests will also be conducted: microbial load tests, routine checks, cultures of biological indicators, verification tests for the population of these indicators, sterility tests, and more.

The process must be revalidated every two years. In the event of modifications to the product or its packaging, either a complete validation or a reduced QP will be performed.

Would you like to know more about the sterilization process validation or IONISOS services? Contact us now; our advisors are here to assist you!