What’s involved in the passivation validation process?

Within the medical device world there is a need to validate the passivation process.  But what does that mean, and how does that work?

Validation is the process of insuring that the passivation process you use will reproduce repeatable and predictable results every time a batch of parts is run through the process. By validating the process you are able to forego subjecting every part to testing to prove that it is properly passivated.

Typically you will here the validation process broken down into three distinct parts: the IQ, the OQ and the PQ.  Let’s look at each part.

The IQ or Installation Qualification is the first part.  It is developed by describing the machine – what is it? what does it do? etc. It also looks at what the components on the machine are, gauges, switches, PLC, etc.  It provides a description of the machine and its parts – what is it and how does it work?

The OQ or Operational Qualification is the second part. It essentially help you verify the IQ – does the machine operate as it is supposed to?  Do the components do what they are designed to do? etc. – does everything work as intended?

The PQ or Process Qualification is the third part of the passivation test. If the IQ is the theory of how things SHOULD operate and the OQ is the practice of how things DO operate, then the PQ defines how CONSISTENTLY the machine operates.  You create a DOE (Design of Experiments) that tests the equipment at the top end and bottom end of allowable ranges and run parts to verify the results across the entire range of the variables. Now when the machine operates within the specified range of time, temperature and/or acidic concentration you know that your parts will meet the specs. That is the goal of the passivation validation process.