Daily calibration helps maintain the accuracy of the instrument. None-the-less, this is not a guarantee that the instrument is functioning to factory specifications. For this reason and for those listed below, X-Rite recommends that instruments be inspected at yearly intervals:
A calibration step wedge, in spite of proper use and care, may change or deteriorate over time. Thus X-Rite always replaces the calibration media when servicing the densitometer. This equally is true of re-certification, repair, and all service contract programs.
Densitometers and sensitometers are critical to processor quality control! X-ray hardware and automatic exposure controls are inspected regularly. Paddle pressure and contact screens too receive regular checkups. This same attention should be applied to all quality control tools. X-Rite recommends yearly re-certification to help ensure the proper functioning of these devices.
Potential problems with the instrument cannot always be detected by the end user. A re-certification service includes many different tests and inspections. This assures that the instrument meets all the Engineering specifications.