The paper proposes methods of accounting for measurement uncertainty and semantic uncertainty when consistently using measurement and classification procedures to classify the state of objects according to their quality indicators. Methods of accounting for uncertainty are distinguished by two approaches: the first one is based on accounting for measurement uncertainty when constructing a classification scale, and the second one is based on presenting the result of measuring a quality indicator as a fuzzy number, the carrier of which is the expanded measurement uncertainty. Using these methods, the state of the object can be classified according to one or more categories of the classification scale, indicating the degree of belonging to these categories. Recommendations for the application of two approaches to account for measurement uncertainty in the subsequent classification are given. The use of one or more fuzzy classification scales is recommended when classifying the state of an object by a single quality indicator or by several quality indicators that are combined into a group indicator after classification using the fuzzy logic operators, such as arithmetic mean, as well as pairwise volume operators. When using single and group quality indicators, measurement uncertainty may be accounted for when constructing a classification scale, that is, when using a fuzzy scale. At the same time, the components of the measurement uncertainty preceding the classification and the vagueness of the expert information that may be used in the classification can be accounted for. In this way, the following components of the uncertainty can be defined: instrumental uncertainty and semantic uncertainty. The use of a clear classification scale when presenting the measurement result as a fuzzy number is recommended when classifying the state of the object according to a complex quality indicator that is related to individual quality indicators by a certain dependence or by accounting for the weighting factors of individual quality indicators. It is shown that when accounting for the measurement uncertainty, the state of the object may be classified into one or several categories of the classification scale, indicating the degree of belonging to each category.