Performance Qualification (PQ)

The Performance Qualification (PQ) is the fifth and final document in the approval process for bringing a stability chamber online.  This testing verifies and validates the User Requirements as listed in the URS.  Depending on the verbiage in a company’s validation program, the Operational Qualification (OQ) can be the same process and interchanged.  The PQ is a timed run of the chambers planned operation to show that the chamber will meet the parameters written into the User Requirements (URS).  The PQ should be written to test each function of the chambers operation.  This protocol should be preapproved before the execution of the testing, to ensure that all areas of compliance are in agreement that the content is correct.

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When writing a PQ protocol, it should be written with a step by step approach to the operation of the chambers intended use functions.  As written, it should document each step as a verification of process used in the validation of the unit.

The protocol needs to include the setup of all support equipment used and supporting documentation.  This documentation should include any controller setting changes, pre-run and post-run calibration verifications of the probes used.  All standards used, need to have their calibration data sheets to be included as part of the validation package.

It should be written into the protocol to check all of functions that impact the operational running of the chamber.  Initially the protocol should include tests to show the ability of the chamber to control the specific parameters for the duration of the run.  The secondary support testing should include system switch overs on redundant systems, cycle processes, timed functions such as defrosts and door openings.  This testing needs to be representative of the process and have duration to include the entire process.  The duration of the test needs to show the stable period before the process, the change in process and the return to stable.  The parameters of the test should be written to require the documentation of the intended processes start and end, so the reviewer has reference points to base review on.  Some test process steps may not show up on the data or affect the operation of the chamber  due to the robustness of the chamber and the data may not show any changes that are easily detectable.  A graphing of data should be included to in the final report to show the process in a graphical display to help the reviewer understand the operation’s performance.

In a cycling process for automated chambers, the protocol should include a test of the changing from one temperature to another to show the duration of the change process.  The duration of these runs should be timed to show the chambers stability, change and return back to stable process after the change.  The testing run should include the lowest, midpoint and highest temperature ranges identified for use in the Design Qualification.  The test run should show a ramping from one extreme to another and back to midpoint.

This supporting data of each run needs to be included and discussed in the final report.

Timing of the functions being tested should meet the requirements as written in the company’s validation program SOP’s.  The duration of a chamber validation run should give an operational review of the chambers actual environmental.  The use of a twenty four (24) hour test run for primary processes gives a view of what a chamber would see in a full day’s operation.

For repetitive processes, such as switch overs and defrosts, the capture of a single event to show the duration and impact to the chamber operation should be documented.

For door openings, the process should be representative of an extensive opening such as opening the door to 90 degrees for a timed duration of one (1) minute.  The testing should document the time the door opened, the time the unit went out of spec and the time it took for the unit to come back into compliance to the operational temperature.  If a door test does not affect the stability of the chamber, a full run of the test still needs to be included as a documentation of the process.

In a chamber that may require that a defrost cycle to happen during a validation run, there should be a discussion at the start of the protocol to identify the issue and an explanation of the possible runs being out of specification.  In the discussion the explanation should identify that the defrost data was extracted from the run and was displayed in its own section to show the impact on the chamber and the clarification of the data missing from the full run.  As a backup, (2) two data files should be saved; one with the defrost cycles included, and the other with the defrost cycle data extracted.

For documentation of probe placement, a photo of each probe should be taken and included in the validation book.  This is a proof positive method of the placement of each probe.  Probes should be labeled for identification.

There should be a tab in the validation binder for each set of data collected for a validation run.  I.E Tab 1 Pre-run calibration, Tab 2 Validation run, Tab 3 Post validation calibration check. The last tab in the binder should contain a long term media stored copy of all the data generated.  All files that require a special program to open for review should be labeled as such, to identify the requirement to prevent corruption and loss of data at a later date.

The Final Report of the PQ should discuss each test and clarify that the test was successfully completed.  The placement of a table at the beginning of the Final Report that displays compliance to all test requirements, allows the reviewer see an overview of the data in the report.  In the discussion of each test run, a graph of the data should be included to provide a graphical display of the data.  At the end of the Final Report, a statement needs to be added that states “based on the data presented the chamber is validated to run at the specific temperature(s)/RH(s) of the validation”.

After completion of the protocol execution, the protocol should be reviewed and approved by the original personnel who preapproved the protocol.



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