Drift Monitors

After establishing a calibration on an x-ray fluorescence instrument everybody likes to use it as long as possible. This wouldn’t be any problem if the instrument would not show any changes in sensitivity over time. But the opposite is the case. The x-ray tube looses intensity over time. The detector looses sensitivity over time too. Service works like changing of an x-ray tube or a crystal might have an influence on the sensitivity as well.

The loss on intensity is not constant for all elements. Light elements from Be to Zn normally show a higher influence than heavy elements.

To use an existing calibration over a long time the change in sensitivity for an element has to be detected by a drift monitor and then used to correct for it. Such samples are called drift monitors, monitor samples, reference samples or monitor standards. A drift monitor must show spezial properties. Such a sample should not show any change of element composition over a long time. Today mostly samples from glass often made from silicate glass are used. However monitors made from metals are also used.

Fluxana (Germany) calibrations, installed by Fluxana in many customer laboratories contain a special selection of drift monitors to guarantee an excellent long term stability. These monitor samples were designed especially for the use in our customer applications. Driven by customers Fluxana produce monitor samples in their glass production designed on the customer need.

Use their online-database FLUXearch (www.fluxearch.com) to find all of their glasses.