How Calibration Intervals are Determined

Calibration intervals are to be determined by the instrument “owner” based on manufacture recommendations. Commercial calibration laboratories can suggest intervals but in most cases they are not familiar with the details of the instrument’s application.

The OEM intervals are typically based on parameters like mean drift rates for the various components within the instrument. However, when determining calibration intervals as an instrument “owner” several other factors should be taken into consideration such as: the required accuracy vs. the instrument’s accuracy, the impact an OOT will have on the process, and the performance history of the particular instrument in your application.

Also be aware that ISO 17025 strongly warns against a calibration lab from suggesting an interval of calibration. That decision should be made by the equipment owner based on history and use.