Reporting uncertainty for gas certified reference materials: balancing customer requirements with calibration and measurement capabilities

2021 ◽  
Vol 26 (1) ◽  
pp. 41-45
Author(s):  
Richard J. C. Brown ◽  
Paul J. Brewer
2019 ◽  
Vol 14 (1-2) ◽  
pp. 9-23
Author(s):  
E. P. Sobina

The State Primary Measurement Standard for units of specific gas adsorption, specific surface area, specific volume and pore size of solid substances and materials (GET 210–2014) is currently in operation at UNIIM. The GET 210-2014 has calibration and measurement capabilities for pore size in a range from 2 to 100 nm, while in practice there is a need to control the pore size of solid substances and materials in a range from 100 to 10,000 nm. In order to enhance the calibration and measurement capabilities of the GET 210-2014, it was proposed to include two reference systems implementing the methods of mercury porometry and stationary filtration into the measurement standard. This work considers the state of the metrology of porometry and presents the first results of studies on the metrological characteristics of reference systems implementing the methods of mercury porometry and stationary filtration. Algorithms for calculating the uncertainty of quantities being reproduced via the methods of mercury porometry and stationary filtration and characterizing the porosity of solids have been developed and tested. The reliability of the developed algorithms is confirmed by: the results of participation in 4 international comparisons, the measurements of foreign-made reference materials, along with the results of participation in 6 rounds of interlaboratory comparisons. The measurement standard improvement will provide metrological support to measuring instruments and measurement procedures for sorption properties, porosity and gas permeability of solid substances and materials in various industrial sectors. Thus, the metrological independence of the Russian Federation will be ensured and import substitution of expensive foreign reference materials carried out.


2020 ◽  
pp. 66-72
Author(s):  
Irina A. Piterskikh ◽  
Svetlana V. Vikhrova ◽  
Nina G. Kovaleva ◽  
Tatyana O. Barynskaya

Certified reference materials (CRM) composed of propyl (11383-2019) and isopropyl (11384-2019) alcohols solutions were created for validation of measurement procedures and control of measurement errors of measurement results of mass concentrations of toxic substances (alcohol) in biological objects (urine, blood) and water. Two ways of establishing the value of the certified characteristic – mass consentration of propanol-1 or propanol-2 have been studied. The results obtained by the preparation procedure and comparison with the standard are the same within the margin of error.


2017 ◽  
Vol 13 (7) ◽  
pp. P1512
Author(s):  
Sébastien Boulo ◽  
Julia Kuhlmann ◽  
Andreas Leinenbach ◽  
Tobias Bittner ◽  
Leentje Demeyer ◽  
...  

Author(s):  
Juliane Riedel ◽  
Sebastian Recknagel ◽  
Diana Sassenroth ◽  
Tatjana Mauch ◽  
Sabine Buttler ◽  
...  

AbstractZearalenone (ZEN), an estrogenic mycotoxin produced by several species of Fusarium fungi, is a common contaminant of cereal-based food worldwide. Due to frequent occurrences associated with high levels of ZEN, maize oil is a particular source of exposure. Although a European maximum level for ZEN in maize oil exists according to Commission Regulation (EC) No. 1126/2007 along with a newly developed international standard method for analysis, certified reference materials (CRM) are still not available. To overcome this lack, the first CRM for the determination of ZEN in contaminated maize germ oil (ERM®-BC715) was developed in the frame of a European Reference Materials (ERM®) project according to the requirements of ISO Guide 35. The whole process of CRM development including preparation, homogeneity and stability studies, and value assignment is presented. The assignment of the certified mass fraction was based upon an in-house study using high-performance liquid chromatography isotope dilution tandem mass spectrometry. Simultaneously, to support the in-house certification study, an interlaboratory comparison study was conducted with 13 expert laboratories using different analytical methods. The certified mass fraction and expanded uncertainty (k = 2) of ERM®-BC715 (362 ± 22) μg kg−1 ZEN are traceable to the SI. This reference material is intended for analytical quality control and contributes to the improvement of consumer protection and food safety. Graphical abstract


2016 ◽  
Vol 99 (5) ◽  
pp. 1163-1172 ◽  
Author(s):  
Pearse McCarron ◽  
Kelley L Reeves ◽  
Sabrina D Giddings ◽  
Daniel G Beach ◽  
Michael A Quilliam

Abstract Okadaic acid (OA) and its analogs, dinophysistoxins-1 (DTX1) and -2 (DTX2) are lipophilic biotoxins produced by marine algae that can accumulate in shellfish and cause the human illness known as diarrhetic shellfish poisoning (DSP). Regulatory testing of shellfish is required to protect consumers and the seafood industry. Certified reference materials (CRMs) are essential for the development, validation, and quality control of analytical methods, and thus play an important role in toxin monitoring. This paper summarizes work on research and development of shellfish tissue reference materials for OA and DTXs. Preliminary work established the appropriate conditions for production of shellfish tissue CRMs for OA and DTXs. Source materials, including naturally incurred shellfish tissue and cultured algae, were screened for their DSP toxins. This preliminary work informed planning and production of a wet mussel (Mytilus edulis) tissue homogenate matrix CRM. The homogeneity and stability of the CRM were evaluated and found to be fit-for-purpose. Extraction and LC-tandem MS methods were developed to accurately certify the concentrations of OA, DTX1, and DTX2 using a combination of standard addition and matrix-matched calibration to compensate for matrix effects in electrospray ionization. The concentration of domoic acid was also certified. Uncertainties were assigned following standards and guidelines from the International Organization for Standardization. The presence of other toxins in the CRM was also assessed and information values are reported for OA and DTX acyl esters.


1992 ◽  
Vol 02 (04) ◽  
pp. 489-491 ◽  
Author(s):  
MOMOKO CHIBA ◽  
VENKATESH G. IYENGAR

Tin (Sn) is one of the causative elements of the environmental pollution. As no certified reference materials for Sn are presently available, existing reference materials were analyzed for Sn by two independent analytical techniques; atomic absorption spectrometry (AAS) and neutron activation analysis (NAA). The results obtained by both methods were in agreement except for mixed diet which contains Sn in the range of 50 μ g/g. Further, tin concentrations in human and animal organs have been examined by AAS. Among organs tested tin concentrations in testes were the highest, 2.08±0.62 μ g/g dry weight (mean ±SD, n=12) in humans, and 1.45±0.55 μ g/g (n=8) in mice.


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