Calibration methods for pH meters: external and/or internal?
We are a flexible packaging manufacturer and make labels for products. We are trying to get SQF certified for the first time this year, so I need a little help in the calibration topic. We use pH meters to test the pH of the inks that we use to print on our film and labels. We have pH testing kits that are provided by the same company that sells the meters to us. Would this be considered internal calibration or would this suffice as an approved method of calibration which would exempt us from outsourcing it?
TIA.
This is an internal activity. You may submit the device to an accredited 3rd party for services, but I don't see the reason for this at least according to section 11.2.11 (if I'm fully understanding your question).
I would think that for your verifications as long as the buffer is traceable to an international/national known reference standard than you should be ok. Your vendor should be more than willing to provide all the necessary paperwork for the calibration buffer.
We use pH meters too: we buy calibrated ones and do internal calibration (against buffer solutions, pH 4 and 7) twice a day. Regarding external calibration (which should be done annually as a pH measurement is our CCP) - we don't do it as our pH meters don't last long, usually 4-6 months, so we buy new ones which're sold calibrated.
You don't have to outsource, you can do so internally - just document it.
Hi,
internal, documented work - every day prior first use.
If several people are using the equipment you can use a label (with red or green dot) to demonstrate the the work is already done. You can used this label although to show that the equipment does not work properly.
Same procedure we are using for balances (check weight 1x/d).
Rgds
moskito
SQF Clause ?
Is the pH related to Safety ?
SQF Clause ?
Is the pH related to Safety ?
Clause 13.2.9 Calibration
The pH testers test the pH level for our inks that we use to print on our flexographic printing packaging. It is more for quality I guess, rather than safety.
Hello,
We use a pH meter to verify the dilution pH on our detergent for cleaning and sanitizing procedures. As long as you calibrate the device internally with your 4,7 &10 buffers and making sure they are traceable your are covered. Make sure you document it!
Hope it helps!