As part of the metrological assurance of the State Primary Standard for Units of Magnetic Induction, Magnetic Flux, Magnetic Moment, and Magnetic Induction Gradient GET 12–2025, precision measurements of the geometric parameters of the KC-4 quartz gauge windings are carried out at five-year intervals.

However, the traditional measurement procedure for the KC-4 is time-consuming and costly, as it requires the use of special equipment, complex methods, and labor-intensive error accounting.

It is possible to optimize the measurement procedure by developing, instead, an alternative method of determining the KC-4 constant without loss of accuracy. Research in this direction is being conducted at the Laboratory of State Standards in the Field of Magnetic Measurements of the D. I. Mendeleyev Institute for Metrology, whose staff are the authors of the article.

The authors of the article focused their search for an alternative method of determining the KC-4 constant based on the resistance-frequency method (Rf-method). The measurement experiment comprised approximately 20 measurement series. Equipment from GET 12–2205 was used, and a procedure for determining the KC-4 constant based on frequency and resistance measurements was implemented.

As a result of the study, the viability of the proposed alternative method was proven. The error of the alternative method established in this iteration of the experiment is five times higher than that of the traditional geometric method for determining the constant. However, potential opportunities for improving the accuracy characteristics of the alternative method were identified.

The results of the study presented in this article will serve as a foundation for further experiments on the development of the Rf-method after improving the equipment and software used. If positive results are obtained in the future, the Rf-method will be implemented into the metrological assurance procedure of the State Primary Standard GET 12–2025. 

The publication contributes to the field-specific discussion prompted by the ongoing redefinition of the International System of Units (SI) within the metrological community and the increased measurement accuracy of resistance and frequency units. The experimental material presented in the article will provide an impetus for the search for optimal solutions to improve the national reference base in the field of magnetic measurements.

Automated weight and dimension control systems (WIM systems) are a crucial tool for transportation organization, an effective factor in ensuring road safety and preserving road infrastructure. Such systems represent a complex of measuring instruments for weight, axle loads, and dimensions of vehicles and are subject to metrological assurance, like all measuring instruments under state regulation.

However, the metrological assurance system for automated WIM systems faces a number of challenges that affect measurement accuracy and law enforcement practice. In particular, significant discrepancies are observed in the determination of key metrological characteristics: parts of the axle load measurement range, the operating speed range, and the relative error.

The objectives of this study are to systematize the problems of metrological assurance of automated weight and dimension control systems (WIM systems) and to propose ways to solve them in order to improve measurement accuracy.

The starting point of the study was a review of the metrological and technical characteristics of the most common approved types of automated WIM systems, based on data from the Federal Information Fund for Ensuring the Uniformity of Measurements. The capabilities of metrological assurance for WIM systems were schematized regarding axle load measurements at various speeds, indicating axle load and speed measurement ranges that are fully metrologically assured, partially assured, and lacking metrological assurance.

A metrological study of the load-receiving modules of an automated WIM system was conducted under dynamic loading using a working standard of dynamic force.

As a result, new calibration methods have been proposed, in particular, modular testing. The necessity of developing dynamic force standards for more accurate replication of real-world loading conditions and for eliminating the risks associated with on-road tests has been substantiated.

The authors are confident that the significance of the topic raised in this article is not limited to the metrological community. Ensuring the accuracy of measurements performed by automated weight and dimension control systems (WIM systems) will have a beneficial impact on the development of the entire transport infrastructure in the country and will contribute to enhancing the safety of vehicle operation.

Non-automatic weighing instruments are among the most widely used mass measuring instruments. In the Russian Federation, both weighing instruments that comply with the requirements of the international standard GOST OIML R 76–1–2011 “ State System for Ensuring the Uniformity of Measurements. Non-automatic weighing instruments. Part 1. Metrological and technical requirements. Tests” and instruments manufactured according to the producer's technical documentation (hereinafter referred to as TU instruments) are permitted for use. Consequently, approaches to testing weighing instruments for type approval purposes are applied depending on the category of instrument.

However, the lack of a unified approach to testing creates conditions for unfair competition among testing centers. An analysis conducted by the Federal Agency for Technical Regulation and Metrology (Rosstandart) in 2025 identified systemic violations in the testing practices of a number of accredited centers.

The first step towards addressing these issues is the analysis presented in this article of the main errors made by testing centers during type approval testing of non-automatic weighing instruments. The review is based on the minutes of the meeting of the commission “Measurements of Mechanical Quantities” under the Federal Agency on Technical Regulating and Metrology (Rosstandart) dated September 25, 2025. Data from 26 federal and departmental regulatory documents have been systematized, including legislative acts, measurement procedures, and Russian and foreign standards.

The analysis has resulted in a consolidated explanation of the requirements of GOST OIML R 76–1–2011 for testing procedures. Particular attention is paid to the requirements for instrument protection, sample selection for testing, temperature testing with sequential heating–cooling cycles, and in-use disturbance tests. It is shown that weighing instruments manufactured not in accordance with GOST OIML R 76–1–2011 fail the conformity testing procedure to this document when its requirements are strictly observed.

This publication is based on the results of the analysis conducted by the Federal Agency on Technical Regulating and Metrology (Rosstandart), aimed at eliminating conditions for unfair competition and threats of unreliable measurement results. In 2025, the updating of GOST OIML R 76–1–2011 was initiated and continues in 2026, with the introduction of clarifications and requirements corresponding to current practice. The findings of the article can serve as a practical guide for this work. The publication is addressed to a wide audience, primarily testers, producers and users of weighing instruments.

Charpy impact testing of metals, along with static tensile testing, forms the basis for assessing their structural strength and reliability across various industries. Currently, the traceability of measurements performed during impact strength testing using pendulum impact testers is ensured mainly by the results of their verification. Existing verification procedures do not take into account the critical significance of one of the main subsystems of the impact tester – the impact and specimen fracture subsystem. As a result, an impact tester deemed suitable based on verification results actually shows overestimated absorbed energy measurement results due to parasitic energy losses.

An analysis of Russian and international standards on impact strength testing, as well as publications by domestic and foreign authors, has made it possible to identify factors leading to overestimated absorbed energy measurement results obtained with classical pendulum impact testers. The conducted interlaboratory comparison tests, on the one hand, confirmed this finding and, on the other hand, substantiated the impracticality of establishing measurement traceability based on the classical impact testing method.

It is proposed to use a reference pendulum impact machine of the highest accuracy, supporting the instrumented test method, as the basis for ensuring measurement traceability to the existing State Primary Standard of the unit of force GET 32–2011. The presence of a force measuring transducer in its composition allows it to be considered a working standard for further transferring the unit of force to reference measures (specimens), and from them, respectively, to instrumented and classical impact testers. It is also proposed to include the reference impact tester directly into the composition of the improved State Primary Standard of the unit of force GET 32–2011 or the State Primary Standard of the unit of impact acceleration GET 57–84.

To eliminate the problem associated with overestimated absorbed energy measurement results, it is necessary to develop and approve the type of force and absorbed energy measures and reference materials. Furthermore, for the widespread implementation of the considered approach, in addition to the State Verification Schedule, it is necessary to develop a unified verification procedure and extend it to all pendulum impact testers operated in Russia.

The measures described above will actually ensure the uniformity of measurements in impact strength testing performed using both classical and instrumented impact testers.

The revision of standards for methods of determining the mechanical properties of metals has revealed an urgent need for the standardization of approaches to uncertainty evaluation that ensure metrological traceability to state primary standards.

The aim of this work is to systematize the methods for evaluating the measurement uncertainty of аbsorbed energy and to identify the dominant factors affecting accuracy.

Based on the classical concept described in GOST 34100.3–2017 (ISO/IEC Guide 98-3:2008) “Uncertainty of measurement. Part 3. Guide to the expression of uncertainty in measurement”, a mathematical and practical comparative analysis of three approaches was carried out.

It has been established that the method for impact testing machines compliant with GOST 10708–82 “Pendulum impact testing machines” is the simplest; the calibration method according to ISO 148-2:2016 “Metallic materials — Charpy pendulum impact test — Part 2: Verification of testing machines” is the most accurate. It is shown that the use of certified reference materials, unlike other methods, ensures traceability to a reference value and automatically accounts for contributions from striking edge and support wear. During the study, metrological contradictions were identified in the new version of GOST 9454–2025 “Metals. Method fortesting the impact strength at low, room and high temperature”: it has been proven that the algorithms proposed exclude friction loss and the initial potential energy of the pendulum, which leads to a dangerous underestimation of the uncertainty evaluation.

The calculated uncertainty budgets showed that, in practice, the dominant sources are scale resolution and misalignment of the centers of percussion. The obtained algorithms are planned to be included in the draft national standard for the verification of pendulum impact testing machines and to be used in the development of new certified reference materials.

In the Russian Federation, the reproduction and transfer of the measurement unit of force in the range from 10 N to 1 MN is carried out using the State Primary Standard of the measurement unit of force GET 32–2011, in accordance with the State Verification Schedule. However, modern industry, at a new stage of its development, has an urgent need to ensure metrological traceability for forces exceeding 1 MN.
The State Verification Schedule for transferring the unit of force in the range under discussion implies the use of the method of combined measurements. This method meets the current requirements of production processes, but it has a number of significant limitations that prevent increasing the accuracy of measuring instruments in the range above 1 MN to a level comparable to the method of direct measurements.

The purpose of the research presented is to consider and study a number of factors influencing the measurement result of force measuring instruments that implement the method of combined measurements.

The starting point for achieving this goal was to identify the factors that reduce the accuracy of the combined measurement method of force when using groups of parallel-loaded dynamometers. To identify and evaluate these factors, the method of analyzing regulatory documents and literature sources was applied. The experimental part of the work was carried out using a group of dynamometers from GET 32–2011. The method of combined measurements was implemented using parallel-loaded dynamometers. Calibration of the additional channels of multi-channel dynamometers was carried out by conducting several series of loadings of the dynamometer on the force standard using a prism.
An analysis of the theoretical framework showed that the central problem is the systematic error arising from the deviation of the applied force vectors from the sensitivity axes of the dynamometers. To solve this problem, a theoretical model was developed to quantitatively assess this influence, along with a new method for calibrating the additional channels of multi-channel dynamometers using a prism, which makes it possible to compensate for this error.

The results of the work presented in the article can be considered as a promising direction for further research into the influence of the factors described in this article on the results of force measurements, suggesting the potential to improve the accuracy of force measurements in the range from 1 to 9 MN.

Metrological assurance of measuring instruments for which periodic verification and calibration are difficult or impossible (so-called non-removable measuring instruments) is limited to initial verification prior to commissioning. With the development of modern instrumentation, such measuring instruments are becoming increasingly in demand, particularly at hazardous production facilities.

However, there is no methodology for monitoring the accuracy of measurements performed using non-removable measuring instruments. As a consequence, there are also no mechanisms for predicting the technical condition and metrological failure of such measuring instruments.

The aim of this work is to review modern approaches to evaluating the metrological characteristics of non-removable measuring instruments and, based on them, to construct a functional model of the operation process of measuring instruments with a built-in measurement accuracy monitoring function. This model will make it possible to predict metrological failure and improve the reliability of measurement results.

The author analyzed key regulatory documents. The methodological materials included MI 3676-2023 “State System for Ensuring the Uniformity of Measurements. Recommendations for determining calibration intervals for measuring instruments. Basic provisions”; GOST R 8.673–2009 “State System for Ensuring the Uniformity of Measurements. Intelligent sensors and intelligent measuring systems. Basic terms and definitions”; GOST R 8.734–2011 “State System for Ensuring the Uniformity of Measurements. Intelligent sensors and intelligent measuring systems. Methods of metrological self-checking”.

As a result, a generalized model of the operation of measuring instruments with a built-in measurement accuracy monitoring function has been constructed.

The obtained results make it possible to simulate the operation process of developed measuring instruments with a built-in measurement accuracy monitoring function in order to determine the necessary design parameters and the values of normalized metrological characteristics.

The article is intended for practical application by developers, testers, and end users of measuring instruments with a built-in measurement accuracy monitoring function.

The widespread use of argon in industry, microelectronics, medicine, metrological equipment, and other industrial sectors predetermines increased requirements for the identification of foreign gas impurities in high-purity argon. Various measuring instruments and methods are used to determine the impurity content in gaseous argon, depending on the expected impurity content.

However, the range of equipment for determining impurities in pure argon is extensive, and the procedure is lengthy and labor-intensive.

The aim of the research is to study the capabilities of an argon discharge detector for the analysis of impurities in high-purity argon, with a view to its integration into metrological practice by equipping chromatographs with them.

The authors compiled a review of the physicochemical characteristics of argon produced in the Russian Federation in accordance with TU 2114-010-05015259-2015 “High-Purity Gaseous Argon (Compressed)”, TU 20.11.11-006-45905715-2017 “Pure and High-Purity Gaseous Argon”, GOST 10157–2016 “Gaseous and Liquid Argon. Specifications”, and TU 6-21-12-94 “High-Purity Argon. Specifications”. Based on these documents, the main methods for analyzing impurities in pure argon were considered: colorimetric, coulometric, electrochemical, and chromatographic methods. A description of the design features of the discharge ionization detector (DID) and its modification, the argon ionization detector (AID), was provided. The operating principle of the argon detector was evaluated; this detector implements a method based on the dependence of the electrical parameters of a high-voltage high-frequency resonant oscillatory circuit on the parameters of the capacitively coupled pure argon plasma.
As a result, the advantages of equipping chromatographs with an argon discharge detector have been established. Its operating principle is based on the dependence of the electrical parameters of a high-voltage, high-frequency resonant oscillatory circuit on the parameters of the capacitively coupled pure argon plasma. The advantages of such a detector include increased reliability of readings, simplicity of design, and reduced labor costs for analysis.

The conclusions of the study showed that a chromatograph equipped with such a detector can be integrated into metrological practice for measuring impurities in ultra-pure argon. Its integration into the complex of installations for reproducing the measurement units of mole fraction, mass fraction, and mass concentration of components in initial pure gases and substances, which is part of the State Primary Standard of units of molar part, mass part and mass concentration of components in gas and gas condensate environs GET 154–2019, appears promising.