Correction for errors due to different quenching for standards and test portions. When using liquid scintillation detectors these corrections can be based e.g. on the standard addition or sample channels ratio method or the use of automated external standardization.
Source:
PAC, 1994, 66, 2513. 'Nomenclature for radioanalytical chemistry (IUPAC Recommendations 1994)' on page 2523 (https://doi.org/10.1351/pac199466122513)