Coating Thickness Gauges

The accuracy of a coating thickness gauge can be determined by a number of factors. A key decision on the selection of a suitable coating thickness gauge is how accurate do you need the readings to be? Generally, the accuracy will be related to the cost of the instrument and higher cost units will usually be more accurate.

Accuracy is the difference between the true coating thickness that should be achieved and the reading. The accuracy with which a gauge takes readings is a critical aspect of a gauge's performance.

Repeatability is used to assess the readings that the same person and the same gauge will be able to achieve measuring the same area.

Reproducibility is used to compare different gauges and ultimately the accuracy of the gauge by comparing different readings by different people with the same gauge.

The best way to check the accuracy of a coating thickness gauge is to use coating thickness standards that have traceability to National Standards. You then adjust the gauge to zero on an uncoated smooth substrate and use a foil standard at or near the maximum range of the gauge to set the specified thickness.