Stages of development of measuring systems are considered, features of their properties and structures, terminology and metrological support are marked.

The relative errors of the standard and expanded measurement uncertainty evaluation arising from the difference of the measuring instrument readings distribution from the Gaussian were investigated.

Questions of checking of multi-channel measuring systems are considered.

The need for instruments to control the size of parts in the processing on grinding machines appeared in the early 40s of the last century in connection with the increase in serial production of vehicles and rolling bearings precision parts. In the semi-automatic grinding machines in-process gauging system have been established. Recent gauges and prospects of their development during the fourth industrial revolution are described.

The theoretical basics of development of suggested combined information-measuring system, utilizing both the absorption and laser-fluorescent method of measurement and estimate of major parameters of crude oil and oil products have been described. The principle of internal calibration of suggested spectral measuring system is theoretically grounded. The duality of suggested principle of internal calibration of spectral absorption measuring systems and possibility for realization of this principle in laser-fluorescent measuring systems is noted.

The results of analysis of normative-methodological support of measurements of catalytic activity, which presents of standards, recommendations, reference measurement procedure and reference materials are shown. The results of work of experts of the International Federation of Clinical Chemistry and laboratory medicine (IFCC), which conducted a full study of the optimized conditions of measurements the concentration of catalytic activity of individual enzymes in the person's serum, are discussed. It is stated that the standard of unit of catalytic activity (catal) in the traditional sense, as a means of implementation of this unit at present is not available. The problems and questions which are needed to be addressed when developing such a measurement standard are formulated.

Quantitative determination of micro-components in substances, materials and environment is complicated by large systematic errors. The traditional methods and techniques of their account and reduction are discussed. It is shown the need to ensure an acceptable trueness of the analysis results in the field of small and very small contents.