(161 days)
The STERIZONE® VP4 Sterilizer is intended for use in terminal sterilization of cleaned, rinsed, and dried metal and non- metal reusable medical devices in health care facilities. The single pre-set cycle of the STERIZONE® VP4 Sterilizer uses hydrogen peroxide and ozone. The injection of vaporized hydrogen peroxide is followed by the injection of ozone, which reacts with residual hydrogen peroxide to form hydroxyl radicals. Sterilization efficacy was demonstrated using a representative sample of one or more device types and packaging, in nine separate validation loads, as described in Table 1 [refer to continuation pages 2 - 4 of this form]. The load to be processed should be maintained between 20℃ to 26℃ (68°F to 78°F). Total load weight shall not exceed 75 lb, inclusive of the containers/packaging weight but excluding the 25 lb loading rack.
The STERIZONE® VP4 Sterilizer (VP4) is a self-contained stand-alone device, using vaporized hydrogen peroxide and ozone in a multiphase process. The VP4 offers a single sterilization cycle intended for general instruments, flexible endoscopes (including single, dual, and multichannel devices), and rigid-channel devices (including single-channel and double-channel rigid endoscopes). The changes to the sterilizer are component changes that were made to extend the of the hydrogen peroxide vaporization block. These changes include: 1] anodization of the hydrogen peroxide vaporization block, and 2] a reduction of the stabilizer concentration in the hydrogen peroxide solution.
This document describes the non-clinical testing and validation of the STERIZONE® VP4 Sterilizer, specifically focusing on changes to the hydrogen peroxide vaporization block and the hydrogen peroxide solution. The primary goal of the study was to demonstrate that the modified device maintains the same safety and effectiveness as its predicate (K173694).
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1. Acceptance Criteria and Reported Device Performance:
The primary acceptance criterion is that the modified STERIZONE® VP4 Sterilizer achieves a Sterility Assurance Level (SAL) of 10⁻⁶ using an overkill approach. It also needed to meet various safety and performance standards.
| Acceptance Criteria | Reported Device Performance |
|---|---|
| Achievement of a Sterility Assurance Level (SAL) of 10⁻⁶ for terminal sterilization of packaged reusable medical devices, demonstrated using an overkill approach and half-cycle testing. | "Sterility testing of directly inoculated medical devices was conducted employing an overkill approach in the modified sterilizers to demonstrate achievement of a sterility assurance level (SAL) of 10⁻⁶." "Testing on directly inoculated medical devices was conducted employing half-cycle to demonstrate achievement of a sterility assurance level (SAL) of 10⁻⁶." "This process has been demonstrated to achieve a sterility assurance level of 10⁻⁶ for terminal sterilization of packaged reusable medical devices." |
| Compliance with various North American safety codes and standards (CSA C22.2 No 61010-1, UL 61010-1, FCC Part 18 / EN 55011, IEC 61326-1, IEC 61010-1:2010, 61010-2-040). | "The modified STERIZONE® VP4 Sterilizer complies with the applicable portions of the following standards." (Followed by a list of standards). |
| All parameters of each part of the test series meeting acceptance criteria. | "In each case, all parameters of each part of the test series met acceptance criteria." |
| No impact on the biocompatibility of the materials of the sterilized devices due to changes. | "The modification did not in any way impact the biocompatibility of the materials of the sterilized devices, since the materials sterilant residuals, have not changed." "The verification tests performed to determine the concentration of post-sterilization H₂O₂ residuals on materials sterilized with the STERIZONE® VP4 Sterilizer equipped with the proposed anodized H₂O₂ vaporization block and the Semiconductor-grade H₂O₂ solution were tested under worst-case conditions." |
| Maintaining safety features and control redundancies as determined by a Failure Mode Effects Analysis (FMEA). | "A Failure Mode Effects Analysis (FMEA) has been conducted on the entire system of the STERIZONE® VP4 Sterilizer to ensure safety features and control redundancies have been implemented in the design and will be maintained during the manufacturing, installation, maintenance and servicing of the sterilizers." |
2. Sample Size Used for the Test Set and Data Provenance:
- Sample Size for Test Set: The sterilizer underwent "nine separate validation loads" as described in Table 1 (pages 3-4 and reiterated on page 7). Each load represented specific types of medical instruments, geometries, and packaging. The text does not specify the exact number of individual items or biological indicators within each load, but it refers to the use of "directly inoculated medical devices."
- Data Provenance: The document does not explicitly state the country of origin for the data or whether it was retrospective or prospective. However, based on the applicant's address (TSO3 Inc., Québec, QC G1P 3S5 Canada) and the FDA submission, the testing likely occurred in a controlled lab environment, most likely in Canada or the US, as part of a prospective validation study for regulatory submission.
3. Number of Experts Used to Establish Ground Truth and Qualifications:
- This document is for a sterilizer device, not an AI or imaging device that requires diagnostic interpretation by human experts. Therefore, the concept of "experts establishing ground truth for a test set" in the context of radiological reads or similar scenarios is not applicable here.
- The "ground truth" for a sterilizer's performance is established by microbiological testing (e.g., biological indicators, inoculated devices) and subsequent culturing to verify the absence of viable microorganisms. The expertise lies in microbiology, sterilizer validation, and engineering, rather than clinical interpretation.
4. Adjudication Method for the Test Set:
- Not applicable as this is a sterilizer validation study, not a study involving human reader interpretation or adjudication of diagnostic findings. The results are quantitative (sterility assurance level) and determined by laboratory methods.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study:
- Not applicable. This is a study on a sterilization device, not an AI-assisted diagnostic tool for human readers. No human readers are involved in the "performance" of the sterilizer itself.
6. Standalone (Algorithm Only Without Human-in-the-Loop Performance):
- This concept is applicable to the STERIZONE® VP4 Sterilizer itself. The device performs its sterilization function autonomously once initiated. The validation studies performed were standalone performance studies of the device's ability to achieve sterility without human intervention in the sterilization process, only in its operation.
- The study demonstrated the device's ability to achieve an SAL of 10⁻⁶ on its own.
7. Type of Ground Truth Used:
- The ground truth for sterility was established through microbiological methods, specifically:
- Directly inoculated medical devices: Devices were purposely contaminated with known resistant microorganisms (likely bacterial spores, given the "overkill" approach for sterilization validation).
- Biological Indicators: Although not explicitly stated as "biological indicators," the "overkill approach" and "half-cycle testing" strongly imply the use of standardized biological indicators or highly resistant microbial challenges to demonstrate the SAL.
- Absence of viable microorganisms: The success criterion for sterility is the complete inactivation of these microbial challenges, confirming an SAL of 10⁻⁶.
8. Sample Size for the Training Set:
- Not applicable. This is a physical device (sterilizer) undergoing validation, not an AI algorithm that requires a training set. The device's operation is based on established physical and chemical principles, not machine learning from data.
9. How the Ground Truth for the Training Set Was Established:
- Not applicable, as there is no "training set" in the context of an algorithm. The device's design and operational parameters are based on scientific understanding of sterilization processes, extensive R&D, and adherence to relevant standards for medical device manufacturing and sterilization.
§ 880.6860 Ethylene oxide gas sterilizer.
(a)
Identification. An ethylene gas sterilizer is a nonportable device intended for use by a health care provider that uses ethylene oxide (ETO) to sterilize medical products.(b)
Classification. Class II (performance standards).