Validation of Laboratory Steam Sterilizers and Autoclaves: Performance Qualification (PQ)

The third in this series of articles aims to discuss the final stage of validating a new steam sterilizer or autoclave before it can be made fully available for production use.

Performance qualification is the process of providing documentary evidence that the as installed and commissioned autoclave or sterilizer will consistently sterilize all configurations of production loads when operated in accordance with pre-defined operating procedures.

Before commencement of performance qualification studies, a number of prerequisites must be met: - Both the installation qualification and operational qualifications should have been completed and the results reviewed. Any corrective actions outstanding should also have been reviewed and the rationale for continuing clearly documented. The following key elements form the basis of performance qualification studies:

1. All process cycles intended for production loads must be subjected to thermometric tests for performance qualification. The autoclave should be tested with actual production loads or if this is not practicable, suitably qualified simulation loads may be used.

2. The configuration of the load under test should be documented either by a sketch or preferably a digital photograph can make an ideal record. Thermocouples should be located within the load items at positions presenting the greatest challenge to the air removal system. Ensure sensor positions are noted for future reference.

3. The autoclave should be operated under automatic control and the results obtained verified against expected results. The criteria for acceptance will vary, but in all instances, any deviation or discrepancy between the anticipated results to the actual result must be recorded and evaluated for impact on the process.

4. In order to demonstrate reproducibility, the thermometric performance qualification tests should be carried out at least three times in succession. If any of the tests produce results outside permitted tolerances, further investigative and corrective action may be required. This in turn would mean that the series of successive performance qualification tests would have to be repeated following any necessary corrective actions.

For further information and resources relating to autoclave and sterilizer technology, visit http://www.steriliser.co.uk