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Establishing maintenance schedules for derouging and passivation

What is the typical frequency for maintenance of WFI piping systems? Is the use of a calendar based preventive maintenance plan typical for addressing rouge buildup and re-passivation in these system? Or, is inspection based on some criteria used to determine the need?

Evan Schone
Engineering, Maintenance and Utilities Manager - West Point, Pennsylvania, USA
April 17, 2008

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The answer to your question is not simple, of course. (Is it ever?) If you use the system for the same hot WFI all the time on the same schedule, you should be able to put it on the calendar. How often you need to do it depends on how fast the rouge is appearing, and how much rouge you want to have before eliminating it.
It is MUCH easier and faster to do it more often before the rouge gets thick and hard. We have customers who do it every 6 months, and we have some that do it as soon as they can see the rouge. We would be happy to discuss it with anyone in more detail than can be said here on the forum.

Lee Kremer
Stellar Solutions, Inc.

McHenry, Illinois

April 23, 2008

Do you know anyone in the pharmaceutical industry that is not performing de-rouging passivations? Also do you know if anyone has recevied a 483 for not removing the rouge from there systems? Diana

Diana Fischer
Tampa, Florida, USA
June 23, 2008