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Introduction. The article considers the problems of metrological support of catalytic activity measurements. The paper gives certain characteristics of the State Primary Special Measurement Standard for the unit of catalytic activity – KATAL and examines the role of reference materials (RMs) in ensuring the metrological traceability of measurement results.Materials and methods. A method for measuring the concentration of the recombinant protective antigen of Bacillus anthracis and the recombinant GP-protein of the Ebola virus, which means in using «sandwich» enzyme-linked immunosorbent assay, was certified by FGUP «VNIIMS» as a measurement procedure. The following RMs tested by FGUP «VNIIMS» can be used for the development and production of appropriate control samples when performing measurements for comparisons: the RM for the mass concentration of the recombinant protective antigen of Bacillus anthracis in phosphate-saline solution, the RM for the mass concentration of the recombinant GP-protein of the Ebola virus, and the RM for the mass concentration of recombinant Clostridium Difficile toxin.Results. The paper presents the main reactions of the method for measuring the catalytic activity of catalysts for heterogeneous processes, which are also used to carry out exhaust gas cleaning processes.Discussion and conclusions. Thus, conditions have been created for building hierarchies of calibrations of in-demand objects established on the basis of the List of Critical Technologies of the Russian Federation, state programs for the development of industrial sectors.

The present publication begins a cycle of papers of specialists from the Scientific Methodical Centre at the State Service of Reference Materials for Composition and Properties of Substances and Materials. These papers will be devoted to the problematic issues of forming and developing the national market of reference materials in terms of requirements imposed by the current legislation of the Russian Federation concerning of measurement uniformity assurance, technical regulation and accreditation in the national accreditation system.Publications are aimed at giving the reader an insight into the common practice of development and use of reference materials of various categories, state regulation procedures when producing and using reference materials taking into account modern requirements in the field of metrological assurance and measurement uniformity in Russia and abroad, together with necessity and importance of harmonization in the field of reference materials, as well as some other aspects of this activity.This paper discusses main aspects concerning the state of the reference materials market in the Russian Federation and suggestions on its development taking into account modern requirements. The role of state regulation when creating the national market of reference materials in the Russian Federation is shown. The paper specifies possible directions for reference materials production, meeting modern metrological requirements imposed on measurements in the sphere of the state regulation of measurement uniformity assurance.

Introduction: Radiochemical production is one of the richest in terms of data for analytical control, high-quality implementation of which is impossible without using type approved reference materials (RMs). Industry-specific institutes used to satisfy the demand for RMs, many of which nowadays have ceased this type of activities due to various reasons. The paper in question covers problems of metrological support in radiochemical production caused by the lack of type approved RMs.Materials and methods: Technologies used for obtaining homogeneous reference material for radiochemical production are described. Methods and measuring instruments used for certifying RMs are listed.Results: Results of developing certified reference materials at Mayak Production Association are given. Examples of codeveloping RMs of triuranium octoxide and plutonium dioxide are provided.Discussion and conclusions: Assessment of the current situation in terms of provision of type approved RMs is given. The paper provides data on availability of raw material, quality of instrument and methodological base in order to create a reference material production site at Mayak Production Association. Results of step-by-step solutions to problems of metrological assurance in radiochemical production are presented. Research prospects of developing RMs for inductively coupled plasma mass spectrometry are outlined. An outlook is given and practical proposals are formulated in the paper. The proposals in question are related to the interaction between institutes and enterprises of the field in terms of developing type approved RMs.

INTRODUCTION. Liquid penetrant testing (PT) is one of the most widely used non-destructive testing methods for detecting surface discontinuities in nonporous solid materials. This method has shown good results when looking for defects in details made of any nonporous materials including glass, ceramics, plastic, magnetic or nonmagnetic metals or alloys. Penetrant materials and check samples are the main tools for PT. The samples are used to estimate the performance of penetrant materials and to evaluate the sensitivity of the testing technology. AIM OF THE PAPER. The paper aims to evaluate the discontinuity parameters, such as cracks, in non-metal samples to determine the feasibility of using these samples to assess the sensitivity of the testing technology. METHODS. Discontinuity parameters in non-metallic check samples were determined using a microscope, and then the data was statistically processed in accordance with GOST 8.736-2011"Multiple direct measurements. Methods of measurement results processing. Main principles". RESULTS. The conducted study has showed that samples made of non-metallic material can be used to estimate the performance of penetrant families, as well as to assess penetrant testing sensitivity since the cracks in samples are virtually straight.

The paper represents general information of use of reference material (RM) of composition of toxic metal solutions and RM of composition of biological tissues which contain toxic metals (TM) when measuring the TM content in biological materials. The paper describes and analyses the approaches for preparing samples of reference materials which contain Pb, Hg, Cd, Be and TI, developed by the Institute of Toxicology Federal Bio-Medical Agency of Russia and Ural Research Institute for Metrology. When developing, approving and certification of the relevant measurement methods for TM content in biological materials it is necessary to include, as an essential condition, the requirement to use RM of composition of biological tissues which analyte is naturally built in the material matrix as a result of metabolic process. The analogical requirement should be produced when accrediting and licensing medical and biological laboratories and laboratories of chemical and analytical control.

The article is devoted to the development of a reference material of the sorption roperties of nanoporous zeolite, which ensures metrological traceability of measurement results to the State primary measurement standard of units for specific gas adsorption, specific surface area, specific pore volume, pore size, open porosity and gas permeability coefficient of solid substances and materials GET 210-2019.The paper presents the results of theoretical and experimental studies on optimizing the conditions of sample preparation (thermal training) of the reference material using the thermogravimetric method and differential scanning calorimetry, coupled with mass spectrometric detection of the evolved gases (TG-DSC–MS analysis). The results of establishing the metrological characteristics of the reference material are described, including standard uncertainty due to the method of determining the certified value, as well as standard uncertainties from heterogeneity and instability. The GSO 10734–2015 reference material of the sorption properties of nanoporous zeolite (Zeolite SO UNIIM) has certified metrological characteristics: specific surface area (500–1200) m2/g; specific pore volume (0.10.5) cm3/g; the predominant pore diameter (0.4–0.9) nm; specific argon adsorption (0.001–20.0) mol/kg.The reference material is designed to calibrate measuring instruments and to control accuracy of results of sorption characteristics of nanoporous materials measurements; it can be used to certify appropriate measurement procedures, to test measuring instruments and reference materials for type approval and other types of metrological control.

The article is devoted to the development of a reference material of chlorobenzene composition, providing metrological traceability of measurement results to the State primary measurement standard of units of mass (molar) fraction and mass (molar) concentration of organic components in liquid and solid substances and materials based on liquid and gas chromatography-mass spectrometry with isotopic dilution and gravimetry GET 208-2014.The paper considers an indirect method for determining the purity of the starting substance, describes the main stages of development of the reference material, and presents the results of the evaluation of the reference material metrological characteristics, including studies on homogeneity and stability.The reference material of the composition of chlorobenzene has the following metrological characteristics: mass fraction of chlorobenzene (from 993.0 to 999.8 mg/g); molar fraction of chlorobenzene (from 99.30% to 99.98%); the expanded uncertainty of the certified characteristics is 0.02% (at k = 2).The reference material ensures metrological traceability to units of measuring instruments and measurement results, and is intended for verification, and calibration and graduations.

This paper describes measurement techniques, structure, technical characteristics and results of the uncertainty analysis for primary multifunction power standard in the frequency range from 1 Hz to 2500 Hz.

This paper presents the results of a study on the development of alumina-based porosity reference materials (RMs), which are intended for controlling the accuracy of the measurement results obtained using the mercury porosimetry method. These mercury porosimetry RMs are being developed in the Russian Federation for the first time and are primarily intended for verification / calibration and testing for type approval of mercury porosimeters. The study of metrological characteristics was conducted using a reference system, which is to be included in the GET 210-2014 State Primary Measurement Standard for units of specific gas adsorption, specific surface area, specific volume and pore size of solid substances and materials. This reference system was calibrated prior to conducting the study with the use of external reference pressure sensors of the 2nd order at 0.6 MPa and 400 MPa, as well as a laboratory balance (special accuracy class 1) having a maximum weighing limit of220 g. In the course of conducted research work, procedures for reproducing and estimating the uncertainty of porosity characteristics using the mercury porosimetry method were developed. When estimating the PM metrological characteristics, the standard uncertainty, associated with the characterisation and heterogeneity of the studied materials (PM candidates), was evaluated. The standard uncertainty due to instability was disregarded due to the high stability of the alumina matrix. According to the results of the conducted studies, four types of alumina-based porosity PM were developed. Their pore sizes are of about -lOnm; -2,000 nm; -9,000 nm; -60,000 nm. The RMs with pore sizes of -10 nm; -2,000 nm were intended for use in controlling the accuracy of mercury porosimeters operating at high pressures, while the RMs with pore sizes of -9,000 nm; -60,000 nm were for controlling the accuracy of mercury porosimeters operating at low pressures. The developed RMs are different from their foreign counterparts, which are produced by BAM (Germany) and NIST (USA) metrological institutes. The standard uncertainty due to characterisation of the RMs in question was estimated, not by the method of interlaboratory experiment, but by a full analysis of the constraint equations taking into account all sources of uncertainty included in the equations on the basis of the Guide to the Expression of Uncertainty in Measurement. The conducted studies allowed the RM certified values to be traceable at this stage to the GET 3-2008 State Primary Measurement Standard for the mass unit (kilogram), the GET 101-2011 State Primary Measurement Standard for the pressure unit in the field of absolute pressure in the range 1×10–1– 7×105 Pa, the GET 43-2013 State Primary Measurement Standard for the pressure unit in the range 10-1600 MPa and the effective area of the piston-cylinder unit of dead weight testers in the range 0.05-1 cm2. In addition, a reference material having a large pore size of -60,000 nm, which currently has no analogues elsewhere in the world, was characterised.

This paper presents information on the development and certification of reference materials (CRM) for the composition of aqueous aluminium, indium, magnesium, nickel, and titanium solutions.CRMs are represented by aqueous solutions containing aluminium, indium, magnesium, nickel, and titanium ions. CRMs have been packed into 5, 10 and 25 cm3 glass ampoules, as well as into 50 and 250 cm3 polypropylene vessels. The certified values of metal mass concentrations were established according to the preparation method.The certified value of the mass concentration of metal ions in the CRMs under study is found to vary within the range of 0.95–1.06 g/dm3. Both the relative expanded uncertainty (under k= 2) of the certified mass concentration and the relative standard uncertainty due to instability do not exceed the values of 0.8 % and 0.069 %, respectively. The developed CRMs are shown to have the shelf life of 3 years provided that standard storage conditions are ensured. The developed CRMs are included into the RF State Register of Certified Reference Materials under the following numbers: CRM 11122–2018, CRM 11123–2018, CRM 11124–2018, CRM 11125–2018, and CRM 11126–2018. The CRMs produced by the All-Russian Research Institute for Optical and Physical Measurements (VNIIOFI) are characterized by the values of expanded uncertainty comparable to those of world leaders in the production of similar materials.

This paper is aimed at analysing the current state and prospects of metrological support and standardisation in the field of thermal analysis in Russia. Main characteristics of reference materials used for testing, graduating, calibrating, and verifying thermal analysis instruments are described.

This paper describes key stages in the development and investigation of a high-precision certified reference material (CRM) for the composition of potassium dichromate solution. The proposed reference material (RM) exhibits metrological traceability to the units of the International System of Units (SI). Not requiring additional preparation before use, the CRM is convenient for use as a titrant in redox titration.The metrological characteristics of the developed CRM were determined by the direct primary method of coulomet-ric titration using the State Primary Standard GET 176. The interval of permissible certified values of the molar concentration of potassium dichromate in the CRM under study is found to vary from 0.098 mol/dm3 to 0.102 mol/ dm3. The relative expanded uncertainty (k = 2) of the certified value ofpotassium dichromate molar concentration is calculated to be 0.024 %, with relative standard uncertainties caused by long-term and short-term instability each being equal to 0.0044 %. The shelf life of the developed CRM is found to be 1 year, provided that storage conditions are ensured. A procedure for measuring the molar concentration ofpotassium dichromate is described, along with the equipment used. A comprehensive uncertainty budget for the measurements is assembled.The developed CRM is included into the State Register of Certified Reference Materials under the number GSO 10992-2017. The CRM can be used for transferring the mass (molar) concentration unit of a component to RMs and chemical reagents via oxidation-reduction reactions; the verification and calibration of measuring instruments (MI), as well as control of metrological characteristics during MI trials including type approval; MI graduation; validation of measurement procedures; control of measurement results when determining the mass (molar) fraction and mass (molar) concentration of components in liquid and solid substances and materials.

Introduction The introduction indicates the need for the use of permanent magnets in various technology fields. The necessity of measuring the limit magnetic hysteresis loop for the correct calculation of magnetic system parameters is considered. The main sources of error when measuring boundary hysteresis loops are given. The practical impossibility of verifying blocks of magnetic measuring systems element-by-element is noted. This paper is devoted to the development of reference materials (RMs) for the magnetic properties of hard magnetic materials based on Nd2Fe14B, a highly anisotropic intermetallic compound.Materials and measuring methods Nd-Fe-B permanent magnets were selected as the material for developing the RMs. RM certified values were established using a CYCLE‑3 apparatus included in the GET 198‑2017 State Primary Measurement Standard for units of magnetic loss power, magnetic induction of constant magnetic field in a range from 0.1 to 2.5 T and magnetic flux in a range from 1·10–5 to 3·10–2 Wb.Results and its discussion Based on the experimentally obtained boundary hysteresis loops, the magnetic characteristics were evaluated, the interval of permitted certified values was set, the measurement result uncertainty of certified values was estimated, the RM validity period was established and the first RM batch was released.Conclusion On the basis of conducted studies, the RM type for magnetic properties of NdFeB alloy-based hard magnetic materials was approved (MS NdFeB set). The developed RM set was registered under the numbers GSO 11059–2018 / GSO 11062–2018 in the State RM Register of the Russian Federation.

The issue of the role of VNIIMS as the leading scientific organization in the field of legal metrology and the leading scientific and practical centre for metrological support of various sectors of the national economy is considered. The paper provides information on the equipment of the institute with standards in the field of physical and chemical measurements. The characteristics of experimental sample of the State Primary Standard of the unit of catalytic activity – katal, characteristics and fields of application of state standards of units of the VNIIMS in the field of physical and chemical measurements are given. The describes the plans of VNNIMS in accordance with the List of Critical Technologies of the Russian Federation, state programs for the development of industries.

This paper presents the results of the identification procedure certification and subsequent quantitative determination of the active ingredients of two-component injectable medicines (active ingredient and solvent) using Raman spectroscopy. The main objective of the research was to select approaches for estimating the metrological characteristics of the measurement procedure, which include consideration of the methodological parameters and provide the metrological traceability of measurement results to SI units. According to this purpose, the GVET 176‑1‑2010 State Secondary Measurement Standard for units of mass fraction, mass (molar) concentration of components in solid and liquid substances and materials based on volumetric titration was used. The following substances were chosen as the research objects for estimating the metrological characteristics of the measurement procedure: ascorbic acid, novocaine and sodium thiosulphate. The authors of the work have demonstrated the measurement-procedure certification results, whose accurate determination was confirmed by the results of interlaboratory comparisons. The obtained results confirmed the accuracy of the identification procedure and subsequent quantitative determination, which proves its applicability for the determination of the active ingredients in two-component injectable medicines. In addition, the possibility of developing reference materials based on the medicines under study is indicated. Further development of this study may be directed at the development of an identification procedure and its certification, with subsequent quantitative determination of the active ingredients of injectable medicines having three components as well as those having a more complex composition.

This paper presents the results of a series of studies aimed at investigating the reference material (RM) of a multicomponent solution. An algorithm for estimating the uncertainty induced by the chemical element content in the RM is proposed taking into account the mass of the measurand in each component of the mixture. The results calculated according to the preparation procedure using the proposed algorithm were confirmed by the Monte Carlo method, while the elemental content in the mixture was confirmed via inductively coupled plasma optical emission spectroscopy. The applicability of weighted mean estimates for characterizing an RM of a multicomponent solution is shown.

The paper presents information on the development of a new certified reference material (CRM) for mass fraction of dioxins in animal fat, with established metrological traceability. A procedure for preparing and certifying CRM material is given. The GC–LRMS method with isotopic dilution was used as an analytical method for establishing certified characteristics. The uncertainties due to inhomogeneity and instability of the CRM material were estimated in order to account for their contribution to the uncertainty of certified values. In addition, the results of interlaboratory comparisons (ILC) for an experimental batch of the developed CRM are presented. Measurement results provided by ILC participants are shown to be in good agreement with the certified characteristics of the CRM. The certified values of dioxin mass fractions (PCDF group) in the CRM material are established to vary from 1 to 1000 ng / kg, with the relative expanded uncertainty ranging from 10 to 20 %.

This paper considers the participation of FSUE «VNIIFTRI» in international comparisons: in the field of physicalchemical measurements, particularly in pH-metry and ionometry (pX); in the sphere of measuring inorganic components in various matrices. Measurement and calibration capabilities are presented – CMC lines in the BIPM database.

The first part of the article presents the history of creating quantitative NMR analyzers of oil content and humidity of oil crop seeds and their by-products. The developed NMR analyzers differ from similar devices in the availability of metrological support (reference materials (RMs) of approved type) and an extended range of moisture measurement (5–20)%. The main metrological characteristics of the developed NMR analyzer are given. The second part of the article deals with problems solved in the process of carrying out the scientific research work on the development of metrological support for quantitative NMR analyzers. Based on the tasks set, the most optimal substances imitating oil and water components contained in the oil crops and their by-products were selected. The imitation substances in question provide long-term stability of the developed RMs, erewhile being chemically inert to each other, environmentally safe? and allowing an imitation of oil and water in oil crops and their by-products. Organosilicon fluids with (35–40) ms and (95–130) spin-spin relaxation times of protons ms are proposed as an oil imitator. To imitate water, a one-component self-vulcanizing organosilicon compound, which is applied to paper strips with a thin coat, is used in the developed type-approved RMs. In conclusion, the article presents perspective directions of developing RMs of mass fraction imitators of typical fatty acids in the oil of oil crops (sunflower, linseed, and rapeseed).

Purpose. This paper is devoted to investing of the effect of magnetic viscosity on the results of measurements of the main hysteresis characteristics of hard magnetic alloys in an open magnetic circuit of vibrating sample magnetometer.Materials and methods. The studies were performed on a sample of a rapidly quenched nanocrystalline MQP-B+ brand alloy. Hysteresis properties of the alloy in an open magnetic circuit are studied: hysteresis loop, time dependences of magnetization in demagnetizing fields of different intensity, field dependences of the coefficient of magnetic viscosity and irreversible magnetic susceptibility.Results. The dependences of the measurement results of the hysteresis properties on the measurement conditions are established. It is shown that magnetic viscosity must be taken into account when developing hard magnetic reference materials.

The paper presents results of conducting research on the development of a certified reference material (CRM) for specific surface area of quartz sand, which is practically non-porous and therefore has low specific surface area value ~ 0.8 m2/g. The standard uncertainty due to RM inhomogeneity, the standard uncertainty due to RM instability, as well as the standard uncertainty due to characterization were estimated using the State Primary Standard GET 210‑2014 for Units of Specific Absorption of Gases, Specific Surface Area, Specific Volume, and Pore Size of Solid Substances and Materials. The metrological characteristics of the CRM were determined using a low-temperature gas adsorption method. Krypton was used as an adsorbate to increase measurement accuracy.

Introduction. The paper gives information on the development of a certified reference material (CRM) for composition of high-purity copper (Cu CRM UNIIM). The CRM is included as the transfer standard into the State primary standard of the mass (molar) fraction and mass (molar) concentration of the component in liquid and solid substances and materials based on coulometry GET 176-2013.Materials and methods. The CRM represents pieces of oxygen-free copper wire rod, brand KMB, produced according to GOST R 53803-2010, weighing from 0.5 to 1g. The CRM is packed in plastic vials with the capacity of 30 or 50 cm3. The certified characteristic of the CRM is copper mass fraction in copper wire rod, expressed in percentages. The certified value for copper mass fraction was established by the primary method of controlled-potential coulometry using the State primary standard GET 176-2013.Results. The permitted interval of the certified value for copper mass fraction in the CRM is from 99,950 % to 100,000 %. The relative expanded uncertainty (k=2) of the certified value for copper mass fraction does not exceed 0,030 %; the relative standard uncertainty due to inhomogeneity does not exceed 0.010 %; the relative standard uncertainty due to instability does not exceed 0.010 %. The shelf life of the developed CRM is 10 years provided that standard storage conditions are ensured.Discussion and conclusions. The developed CRM is included into the State register of type approved RMs under the number GSO 10800-2016. The CRM of high-purity copper (Cu CRM UNIIM) as a transfer standard is intended for reproduction, storage and transfer of the copper mass fraction unit to other reference materials and chemical reagents by the method of comparison using a comparator and by conducting direct measurements. This CRM may also be used:– for verification of measuring instruments (MIs) according to the state verification schedule described in GOST R 8.735.0-2014,– for calibration, graduation of MIs; control of metrological characteristics when conducting MI tests, including for the purposes of type approval;– for validation of measurement procedures, accuracy control of measurement procedures in the process of their implementation.

Advances of elemental analysis in geology are defined by the development and improvement ofphysical, instrumental methods of chemical analysis. New instrumental methods - emission spectrometry and mass spectrometry with inductively coupled plasma (ICP) sources are the most popular in the area of elemental analysis in recent years. These methods have a very high sensitivity and wide range of elements analyzed (up to 70 items at a time). Both of these methods have been developed and demonstrate their high analytical performance only when analyzing liquids. Consequently, when using these methods in geology, solid samples must be completely transferred into liquid. This complicates the analysis, especially in the analysis of sparingly soluble objects. In some cases, analyzed geological objects are generally insoluble in acids and other solvents (e.g. such as black shales are not dissolved till the end in any acids). Naturally, there is a need to develop an analytical method, wherein the step of dissolution of the sample can be avoided. Such instrumental methods exist but are not used because of low sensitivity. Method of glow discharge mass spectrometry has the greatest potential today, but its use is hampered by lack of a recognized certified ion source capable of converting analyzed (in most cases - not conductive) geological sample into low-temperature plasma. In this paper, the glow discharge source on the basis of the hollow cathode is used as an external source. The hollow cathode has been long and successfully used in analytical practice in emission spectral analysis. However, for use in mass spectrometry, its design has been considerably modified. The analyzed sample, which was formerly in the form of powder or fine particles located at the bottom of the hollow cathode, in a new cathode is installed as a rod along the axis of the inner cathode cavity - it is the emitter of sputtered neutral particles. Hollow cathode source is set on the high resolution mass - spectrometer of ELEMENT 2 type instead of the ICP source. In sample preparation a geological sample is transformed into ultrafine state (particle size of about one micron), this thin layer of powder is applied to the emitter. Particles are held on the emitter (cathode) by van der Waals and electrostatic forces, are bombarded with argon ions, they can be also effected by electrostatic forces - between the emitter and the anode voltage of several hundred volts is applied. As a result, the charged ultra-disperse particles break away from the - emitter and diffuse into the glow discharge. Getting into the negative glow particles are heated by the electron current, then evaporate and ionize. The low-temperature plasma is formed. Mass spectral line of each element consists of many individual spikes lasting 10-30 msec. Each spike is the result of evaporation and ionization of individual particles. Mass spectral lines can be smoothed in the summation series of mass spectra. The proposed method allows direct analysis of geological samples with sensitivity ppb or less without dissolving the sample, without concentration of impurities.

Conformity assessment is the activity to determine whether specified requirements relating to a product, process, system, person or body are fulfilled. Often measurements are used to show that the measurand is within (legal) tolerances. Currently analytical methods are available to test whether tolerances are met with a preset level of confidence, e.g. 95%. The test requires the availability of the overall measurement uncertainty and the statistical distribution of the measurand. In absence of better information this distribution is assumed to be Gaussian. The new point in this paper is that Monte Carlo methods can be applied directly to perform the conformity assessment. The reason is that the Monte Carlo process generates the cumulative distribution, whereby the (legal) tolerances can be compared directly. The advantage of this process is that the type of distribution does not need to be known and the (worst case) assumption of the distribution being Gaussian can be avoided. Consequently, for a Monte Carlo method the difference between tolerances and acceptance criteria is slightly smaller than for analytical methods. A test of the Monte Carlo method applied to a calibration of a high-pressure gasmeter meeting MID tolerances demonstrates the applicability of the method in practice.

The paper describes the results of standardless quantitative XRD phase analysis (QPA) of 5 reference samples of elemental composition of sulphidic ore and technological products from Olimpiada gold deposit. The conformance between measured mineral composition and certified elemental composition is evaluated. Possibilities of the standardless QPA for determination of phase composition of the reference samples are discussed.

Rationale. The reference material of composition with the established metrological characteristics including a certified value and an expanded uncertainty is necessary to ensure an effective accuracy and precision control of results of element composition determination in food ingredients and products. This paper represents the development of a reference material of food crop composition for selenium, nitrogen, phosphorus and potassium content. Methods. To identify the selenium the hybrid atomic absorption method was used, to identify the nitrogen and phosphorus the photometric method was used, to determine the potassium flame-photometric method was used. When determining the metrological characteristics of the reference material the Russian national instructions and recommendations MI 3174-2009 and P 50.2.058-2007 were applied. Results. Based on the research findings the reference material of Chinese cabbage composition with a certified value and an expanded uncertainty was developed: for selenium 0.044 ± 0.017 mg/kg; for nitrogen 4.09 ± 0.27 %; for phosphorus 0.69 ± 0.14 %; for potassium 2.87 ± 0.22 %.

The paper is devoted to the aim and objectives of creating a web portal for State Service of Reference Materials of Composition and Properties of Substances and Materials (Decree of the Government of the Russian Federation № 884 of 2 November 2009 (as worded by Decree of the Government of the Russian Federation № 882 of 04.09.2012)) (herein after - SSRM web portal). It includes information on the main information blocks of the web portal and development prospects. The SSRM web portal was developed in order to form a unified information resource of SSRM, asan inter disciplinary structure responsible for meeting the demands of the Russian Federation for reference materials (RMs). The web portal's objective is to notify all participants involved of the RMproduction, analysis and prediction of demand for RMs, development of RM projects, development of technical and methodological documents specifying RM production and use, involvement in international collaboration as pertaining to RMs. The SSRM web portal is located at the following URL www.gsso.ru.

The paper presents a summary of analyzing Technical Regulations of the Customs Union TR TC 029/2012 "Safety Requirements for Food Additives, Flavorings and Technological Processing Aids". Information on certified reference materials (RMs) for composition of citric acid is provided. Certified characteristics of the RM are, on the one hand, mass fraction of the base substance and, on the other hand, mass fraction of impurities - toxic elements (lead, arsenic, cadmium, mercury). The first batches of the given RMs are produced, which are registered in the State Register of the approved types of certified reference materials GS010300-2013 and GS010143-2012.