Description: The estimation of uncertainty is necessary for many measurements. On the basis of an interval, which is specified by the extended uncertainty of the outcome of measurements, the conclusion of the compliance with the requirements of the standard is made. In the given article the estimation of the extended uncertainty using modeling and empirical approaches on an example of determination of chlorides in potable water is considered. The comparison of outcomes and the prospects of the application of different approaches in the estimation of the uncertainty in practical measurements are indicated.
Keywords: the uncertainty of measurements, methods of the estimation, practical outcomes