Uncertainties in 63Ni and 55Fe determinations using liquid scintillation counting methods

The implementation of 63Ni and 55Fe determination methods in an environmental laboratory implies their validation. In this process, the uncertainties related to these methods should be analysed. In this work, the expression of the uncertainty of the results obtained using separation methods followed by liquid scintillation counting is presented. This analysis includes the consideration of uncertainties coming from the different alternatives which these methods use as well as those which are specific to the individual laboratory and the competency of its operators in applying the standard ORISE (Oak Ridge Institute for Science and Education) methods.

► Uncertainty terms in 63Ni and 55Fe determinations are described.
► Other source of errors coming from different chooses in the methods are analyzed.
► Some recommendations on chemical yield, blanks and calibration sources are provided.