Traceability in gamma-ray spectrometry.

The new edition of the International vocabulary of metrology-basic and general concepts and associated terms (VIM) defines metrological traceability in a different way than was defined in the previous edition. The reference to an "unbroken chain of comparisons" is replaced by a "chain of calibrations." Calibrations, unlike comparisons, render possible an interpolation of the quantity values between indicated parameters where the calibration was performed. Calibrations of software may be performed using software-measurement standards as well. Furthermore, the traceability of quantities having a minor influence on the measurement result is not mandatory. As a consequence of these modifications, the traceability of gamma-ray spectrometric results can also be attained when gamma-ray spectrometry is implemented other than as a relative method.