How often do I need to calibrate my Fluorescence sensor?

Frequency of calibration for the Fluorescence sensor is a function of how clean the sensor optical channel is, which is related to the quality of water sample the sensors are exposed to.  At a minimum, once per month sensor cleaning followed by a zero calibration using DI Water and a slope calibration using a PTSA-100-FL (100ppb PTSA) / 50ppb Fluorescein ) calibration standard is suggested.  If the sensors are exposed to very dirty samples you may need to do this more frequently (ie. Weekly).

Here is a link to a video showing the sensor cleaning process using the cleaning solution and calibration standards:    https://www.youtube.com/watch?v=hFmk2znyvjs&pp=ygUOcHl4aXMgY2xlYW5pbmc%3D