Standard samples and control samples both refer to national standard reference materials; they are essentially the same substance. However, a standard sample is used just before the instrument leaves the factory to set the elemental content values, which ensures the testing instrument's repeatability and accuracy.
So when do you need a control sample? Our instruments use a comparative analysis method. When a customer uses the instrument, slight changes in its mechanical performance—due to differences in air pressure, humidity, or temperature—can cause the light intensity to drift from the values set during the factory calibration. At this point, a control sample is needed to calibrate the instrument's difference coefficient, which helps achieve accurate test results.
Therefore, control samples are indispensable during the instrument's operation. Customers select the appropriate control sample based on the specific material grade they need to test.
