This is not as uncommon as you might think, and there are a variety of ways to do it.
First - pretend it is a new piece of equipment and process, with the exception of using your current knowledge for process characterization.
Second - do a combination of retrospective and prospective validations. For instance, you may have an installation report somewhere that can serve as the basis of IQ. If not, potentially your deviation/maintenance information can go a long way toward it, when pulled together with a requirements list. For OQ, do you currently have any data on how well the process operates at the extremes of your process variables? If so, you can potentially pull this together in support of your OQ. Also, process characterization data could be pulled together to identify the "worst cases" for a limited OQ.
For PQ, it is possible that you collect enough control data during your process to put together a retrospective PQ - I'd suggest first determining what data you have available that potentially can be used.
g-
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Ginger Glaser RAC
Vice-President, Engineering
MN
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Original Message:
Sent: 20-Aug-2017 22:14
From: Susan Jackson
Subject: IQ/OQ on existing equipment
Some advise please,
we have established equipment installed over 10 years ago,
We are going to start to make Pharma products.
Currenlty making cosmetics and nutritionals.
Going forward with OTC proutcs put us in the need for process validation.
How should I go about to cover retrospective IQ/OQ is third possibllity.