«Ural Scientific Research Institute for Metrology» (UNIIM), Ekaterinburg, Russia:

M. Y. Medvedevskikn, Head of Laboratory, Candidate of Engineering Sciences, lab241@uniim.ru
A. S. Sergeeva, Researcher,Candidate of Engineering Sciences

ZAO «LECO CENTER-M», Moscow, Russia:
S. A. Nazimov, Head of Department

National University of Science and Technology «MISIS», Moscow, Russia:
V. I. Minaev, Leading Engineer, Candidate of Engineering Sciences

System for ensuring the accuracy and traceability of measurements is considered to be the basis of coal quality management, both at manufacturing plants that produce and process coal products, as well as in claims work. One of the important parts of control of the accuracy and precision of measuring the quality and safety of coal products is the availability of a wide range of standard samples of the approved type of coal composition. Taking into account the high variability of the composition of fossil coals, both physical and chemical, the nomenclature of standard samples for the provision of the Russian carbon chemical laboratories should be represented by a large number of certified reference materilas (CRM), differing in rank, ash content, petrographic composition, heat resistance, content of basic macro and microelements, chemical composition, etc. Up to the present time, CRM on coal composition are represented on the Russian market by single samples. The article gives an overview of the state of the problem, examines the theoretical issues of creating reference samples for metrological provision of means and techniques for measuring the composition and properties of coals.The order of tests for the approval of the type of CRMs of coal and coke composition using high-precision measurement procedures, state primary and secondary measurement standards, results of interlaboratory experiment is considered. The measurement ranges, accuracy, repeatability and interlaboratory precision of the developed high-precision measurement procedures of ash content, volatile matter and mass fraction of sulfur in solid mineral fuel are given. Metrological characteristics of CRMs of coal and coke composition the material of which are calibration samples produced by LECO Corporation (USA) are presented. The prospects for further development of CRMs for the coal industry based on laboratory samples of coals mined at Russian fields are considered.

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