Questions on Cleaning Validation Swab Area

The Question posed on LinkedIn: (seems to be a dead conversation now).

In a cleaning validation program, Which swab area is preferred ?

In any cleaning validation program, two common sample methods usually used.
One is rinse sampling and the other is swab sampling.
For swab sampling, some companies choose to use a 25 cm² swab area, others are using a 100 cm².
As per my limited info, no regulation ask to use a specific swab area.
But since you choose to use one of them, there must be a scientific rational/ justification, right ?

is it because, the larger is your swab area, the greater residues you can swab and recover ?

practically, some factors affect and effected by determining a swab surface area, Like ; recovery, the swabbed equipment part, residue limit..etc.

so, what is yours ?

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Questions About What To Do With Lids When Air Sampling

The Question posed directly:

“Hi. I have a cleanroom question. When collecting an air sample with an air sampler device can you put the impactor head down when changing the plate.  Can you put the lid of the plate down when you change the plate.  What do you do with the two lids when changing the plate as I thought you could not put them down.


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Questions on Depyrogenation and Viable Environmental Monitoring

The Question posed on LinkedIn:

Hi all, I need your support to find the answers of the following questions:
1. Using manual cleaning of glass vial before sterilization in dry oven in aseptic process for lyophilized product which means no depyrogenation , is it acceptable? and if yes, what is the requirement that should be provided to the inspector as evidence of no contamination (as documents / studies/ gown).
2. Is it mandatory to conduct viable and non-viable monitoring in the ascetic process during the capping and crimping?
Thanks in advance…

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Question on Microbiological Testing of Finished Goods

The Question posed on LinkedIn:

I have a question on microbiological testing of finished goods. We normally do TCP and Yest and Mold, however some customers are saying that pathogenic bacteria test is required after an enrichment is done. Is this really necessary if the PET passes and the TCP and Yest and Mold are less than 10 cfu?”

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What is Data Trending and How To Identify, Action and Report Trends

The following is an article I placed on LinkedIn and was written as part of my Developing My Writing While Helping Others series.

Paul Yeatman is a microbiologist with over 15 years’ experience in documentation, validation and running investigations in TGA and FDA regulated environments. He has a strong interest in process improvement, documentation, training and developing others. From 9-5 Paul investigates and solves software problems.  By night he works on his science chops.  He has an arty streak, runs several blogs and enjoys communicating his experiences and knowledge in arenas such as this. Continue reading