Client: XYZ
Industry: Medical Device Manufacturing
Service: Annual Dose Audit – Gamma Irradiation
Location: Gujarat, India
Background
XYZ manufactures Class II medical devices which are sterilized using gamma irradiation. To comply with ISO 11137-2 and maintain their sterilization validation, an annual dose audit was required. The audit ensures the continued effectiveness of the prescribed sterilization dose used during routine processing.
Objective
To confirm that the selected sterilization dose remains appropriate by evaluating the bioburden and verifying the SAL (Sterility Assurance Level) of 10⁻⁶.
Methodology
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Sample Collection
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10 product samples were randomly selected from routine production.
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Samples were handled aseptically and transported to the microbiology lab.
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Bioburden Testing
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Bioburden was determined using membrane filtration.
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Results ranged between 15–120 CFU per device.
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Verification Dose Experiment (VDmax)
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Based on the ISO 11137-2 standard.
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Samples irradiated at verification dose.
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Sterility test performed on 10 samples.
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Sterility Testing
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Incubated in fluid thioglycollate and tryptic soy broth for 14 days.
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No microbial growth observed in any sample.
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| Parameter | Outcome |
|---|---|
| Bioburden Level | Within specification |
| Verification Dose Passed | Yes (10/10 sterile) |
| Conclusion | Sterilization dose valid |
Conclusion
The dose audit confirmed that the prescribed sterilization dose is still valid for the medical devices. The company remains compliant with ISO 11137, and the validated dose continues to achieve the desired SAL of 10⁻⁶.
Regulatory Impact
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Maintained ISO 13485 & ISO 11137 Compliance
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Ready for upcoming customer and third-party audits
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Demonstrated robust sterility assurance system