How are XRF results corrected for substrate bias?

The approach to correcting X-ray fluorescence (XRF) results for substrate bias typically involves making adjustments to account for the influence of the material beneath a lead coating. This bias occurs because different substrates can affect the readings obtained from the XRF analyzer, resulting in inaccurate lead concentration values.

Subtracting a correction value is an effective way to address substrate bias. This correction value is established based on known interactions between lead, the specific substrate, and the XRF analysis. By subtracting this value from the raw XRF data, the analyst can yield a more accurate concentration of lead in the material being tested, thus providing a result that is reflective of the actual lead content rather than being skewed by the substrate’s characteristics.

Other options like averaging results, adding a calibration factor, or using a standard reference may play roles in different contexts but do not specifically target the need to correct substrate bias effectively in the same way that subtracting a correction value does. Each of these approaches might be useful in their own right for other analytical processes, but when it comes to directly addressing substrate bias in XRF results, subtracting the correction value is the most precise and relevant method.