Dissolved Oxygen Measurement FAQsSource: YSI, a Xylem brand
Q - How often should I calibrate my dissolved oxygen meter?
A – As a rule, YSI recommends that a calibration be performed or verified daily, before sampling starts. But in general, calibration frequency is determined by the user and the importance of the data. The more critical the data, i.e. when used for compliance purposes, the more attention that should be paid to timely calibrations.
The calibration of newer optical based dissolved oxygen meters is very stable but YSI still recommends that it be verified on a regular basis to ensure accurate data.
Your data is as good as your calibration.