A calibrated pH meter is critical for getting accurate results as your pH electrode response will drift over time. Whilst calibration is easy and only takes a few minutes it is often overlooked.
How often should you calibrate your pH meter?
The short answer is as often as you need to, depending on your application and the accuracy of the results that you require. The frequency of calibration may also be determined by the protocol you are following such as FDR or Good Laboratory Practice guidelines. These may require you to calibrate each lot or each shift/user.
How does pH electrode age affect calibration?
As your electrode ages the concentration of the electrolyte decreases, which will make the response slower and also cause it to drift. The drift will often occur more rapidly for older electrodes, hence you will need to calibrate them more frequently and the calibration procedure will take longer.
At some point you will need to change your electrode as they will be difficult to calibrate and drift. As a general rule you should change your electrode if the offset is greater the +/-30mV or your calibration slope is less than 80%.
How does DataWorks Help?
The DataWorks app provides a simple, intuitive calibration procedure, with detailed on screen instructions – so you never need to go looking for your meter manual again. Your calibration history is also included so you know when you last calibrated and the calibration results – ensuring your data is always accurate.