Re validation of Purified water system

Dear All
If there is inclusion of sampling point in previously validated system, then how it can be re-validate? what documents to be revised like DQ, IQ etc… Should Re-validation to be done for only that new sampling point or for whole system means all sampling point? and also for how long period?. And during this period, water can be used for routine use.

Please confirm if you are referring inclusion of “Sampling point” or “User point” in a validated water system.
In case of inclusion of “Sampling point” WITHOUT MODIFYING EXISTING VALIDATED WATER SYSTEM, A revalidation may not be required. But only monitoring of water quality from the newly included “Sampling point” is required along with routine monitoring.
Additionally, there should be written justification provided for inclusion of “Sampling point”. This shall be executed through Change control system.

Dear Mr. Sunil,

i agree with you,
Could you please tell me the:

  1. Period of sampling—
  2. Frequency of sampling–
    3.Any addition test required besides water specs-EP/USP


Sampling period depends upon trend analysis of quality attributes of water sampled from newly included sampling point. I suggest you cover period similar to phase-1depending upon trend.
Subsequently, you can reduce the frequency of sampling and analysis and include this point in routine schedule.

1 Like

ok, Thank you, any reference guideline, or its industrial practice!!


You are welcome…
You may refer USFDA guidelines. However, this is an industry practice. Please note that some times, you may not find everything in the guidelines. In such cases one has to apply his/her knowledge, experience and sound scientific thinking on the subject matter.


Dear Mr. Sunil,
We will plan to included no User points in already validated water system

1 Like

OK. I have already answered your question.