The new international standard ISO 11929:2010 and a recent, moregeneral publication by the outhors of the present paper provide for a non-negative radiation measurand definitions of the best estimate, the associated standard uncertainty of measurment, limits of coverance intervals, the decision threshold and the detection limit, here summarized by the term characteristic values. These values are based on Bayesianstistics and the ISO Guide to the Expression of Uncartainty in Measurement (GUM) and are mathematically defined by means of moments and quantiles of probability distributions of the possible measurand values. During the preparation of the documents, some criticisms were already expressed and alternatives proposed. These are described and discussed in order to achieve agreement between the experts which can be used for a future revision of ISO 119292:2010.