In-plant reference material for composition of Chinese cabbage with certified selenium content was developed for accuracy control of the results of selenium determination and within-laboratory quality control of analytical work in the analysis of food raw material.

The article focuses on the approved types of CRM for petroleum products composition and properties, their producers, theoretical and actual need for CRM. The tests supply analysis of petroleum products main types by CRM was carried out.

The article presents the results of research carried out FSBI "SCEMAP" of the Ministry of Health of the Russian Federation in order to bring qualification procedures for opacity standard samples of bacterial suspensions in line with current requirements for certified reference materials. The studies include: the justification requirements for the certification of opacity standard samples of bacterial suspensions, the development of the program and procedure of its evaluation, validation of the measurement procedure for the certified characteristics, statistical analysis of test results and calculation of metrological characteristics.

The notion of proficiency testing, interlaboratory comparison, proficiency testing scheme is given. The main types ofproficiency testing schemes that meet international standards is describes. The possible uses of certified reference materials for the purposes of proficiency testing is reviewed. The activities of foreign and domestic proficiency testing providers is briefly describes.

The article describes the uncertainty sources for the main stages of quantitative measurements by NMR method. It is shown that the NMR method is effective for measuring of the components molar ratio, the components relative weight portion and the components absolute content during the reference standards certification.

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.