SITE CONSTRUCTION FOR STANDARD SAMPLES DEVELOPMENT AND CERTIFICATION

30 Projects to the 30th Anniversary of NNC RK!

Project # 23. 2015–2022. SITE CONSTRUCTION FOR STANDARD SAMPLES DEVELOPMENT AND CERTIFICATION

     In 2017, a project implementation on site construction on NNC base was initiated supported by JSC “Science Fund” for development, production, certification and re-certification of standard samples for radionuclide and elemental composition of different environmental matrixes mainly of bulk type. Under the current project, at technical support of the International Atomic Energy Agency (IAEA), reconstruction of laboratory complex, about 70 m2 in area, was made to create a technological base for standard samples development.

     The building was reconstructed to meet special interior decoration, providing with the possibility to work with standard samples in the same way as operating with sources of ionizing radiation meeting all requirements of RK and IAEA regulatory documents set for premises meant for standard samples preparation (ISO Guide 34-2014). Moreover, laboratory equipment was purchased in the amount of about 100,000 Euro, that considerably simplified and speeded up the work on standard samples creation.

     At present, this site is the only one in Kazakhstan designed for production standard samples of radionuclide composition, provided with hardware base, complex approach in service rendering, extended experience in radiation safety and rendering service on metrological characteristics identifying at different testing objects. To confirm quality of the site operation, inter-laboratory results matching is carried out regularly.

     The institute members passed training in the preparation and certification of standard samples of radionuclide composition on the basis of Belarusian State Institute of Metrology, as well as creation and certification of standard samples of radionuclide and elemental composition in the laboratory of the International Atomic Energy Agency in Seibersdorf (Austria).

      Standard samples, developed in NNC RK, may be applied to provide internal quality control of analytical tests in laboratories, engaged in radioecological comprehensive studies, and in development and validation of analytical methods of measuring.

      The main material in sample NNC RK production is natural objects of Semipalatinsk Test Site (STS) of various radionuclide composition (natural and technogenic) with a wide chemical elemental spectrum, providing 100 % of Kazakhstani content of products in standard samples production.

      The experience of interlaboratory studies has shown that the correctness of analytical results is better checked by “natural” standard samples, rather than by artificial mixtures prepared from chemical reagents. Economical expediency of producing standard samples consists in the use of earlier obtained data on radioecology and chemical composition of STS natural objects. For instance, previously obtained topographic data allow to determine the most suitable initial materials for selection out of candidate standard soil samples from STS territory without additional studies.

       The main stages in production and certification of standard samples are as follows: initial material selection, laboratory sample preparation (drying, grinding, sieving, homogenization), standard sample analytical study, certification of standard sample characteristics and its uncertainties. The final stage – is a metrological expertise and approval of state standard sample types in authorized agency.

       4 state standard samples with known content of technogenic radionuclides and chemical elements have been developed in NNC RK, namely:

–– Standard sample of 137Cs, 90Sr radionuclides specific activity, mass of Zn, Cu, Pb, Cd, Co, Fe, Mn, As elements in soil cover at STS, KZ.04.01.00007 -2020;

–– Standard sample of 152Eu, 60Cо radionuclides specific activity, mass of Zn, Cu, Pb, Cd, Co, Fe, Mn, As elements in soil cover at STS, KZ.04.01.00008-2020;

–– Standard sample of 241Am, 239Pu radionuclides specific activity in soil cover at STS, KZ.04.01.00012-2020;

–– Standard sample of natural radionuclides specific activity and elemental mass in chestnut soils, KZ.04.01.00034-2021.

      SS developed may also be of great interest for the international community, in particular, to supplement material base of the IAEA.