This part of ISO 11929 specifies a method for determination of suitable statistical values which allow an assessment of the detection capabilities in spectrometric nuclear radiation measurements, and of the physical effect quantified by a measurand (for example, a net area of a spectrometric line in an alpha- or gamma-spectrum) which is determined by evaluation of a multi-channel spectrum by unfolding methods, without the influence of sample treatment. For this purpose, Bayesian statistical methods are used to specify characteristic limits.