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Published in Jacques Buffle, Herman P. van Leeuwen, Environmental Particles, 2019
Standard (or Certified) Reference Materials (CRMs) constitute the basic means for assuring measurement accuracy. A partial list of such materials, suitable for atmospheric particle measurement validation, is given in Table 4.113 Additional CRMs exist or are under discussion for isotopic, carbonaceous, and microanalytical measurements.114 For example, a second urban particle standard, SRM 1649, was collected in Washington, D.C., and certified for a number of organic compounds, notably polycyclic aromatic hydrocarbons. This supplements the certification of SRM 1648, which was collected in St. Louis, for inorganic species. An additional material that is suitable for atmospheric particle quality control is SRM 1650, diesel soot. For measurement of 14C, the basic standard is SRM 4990C; a certificate for this material is reproduced in Figure 25. Another material, RM21 graphite, is appropriate for air particulate stable isotope (13C) quality control. Table 522 includes some (informational) results obtained for carbon isotope measurements on different chemical fractions of two of the above SRMs.
Reference Methods for the Measurement of Pollutants in Environmental Matrices
Published in Leo M. L. Nollet, Dimitra A. Lambropoulou, Chromatographic Analysis of the Environment, 2017
European reference materials (ERMs) are a tool for improving the confidence in, and the mutual recognition of, test results and certificates in the European market. The certified reference materials (CRMs) comply with high metrological requirements, ensuring the traceability of measurements results, and are the end point of the traceability chain, thus being primary standards in chemistry.
Introduction
Published in Jamie Bartram, Richard Ballance, Water Quality Monitoring, 1996
Jamie Bartram, Richard Ballance
Certified reference materials (CRMs) are matrix-matched materials with assigned target values and assigned ranges for each variable, reliably determined from data obtained by repeated analysis. Target and range values may be generated from data produced by several laboratories using different analytical methods or calculated from data obtained by the use of one analytical method (usually a reference method). Consequently, there may be bias in the target value. The target values assigned to each variable in the matrix in certified reference materials are generally very close to the true value. For some variables, however, there is an appreciable difference in bias between different analytical methods and this may lead to wide assigned ranges. When a laboratory is not using one of the reference methods the “all method” range may be so wide that it is practically meaningless. Certified reference materials are also only practical for variables that are stable in long-term storage.
The importance and availability of marine certified reference materials
Published in Critical Reviews in Environmental Science and Technology, 2022
Chintankumar Padariya, Małgorzata Rutkowska, Piotr Konieczka
The following are the three main ways to produce CRMs:an already certified reference material;two or more independent, reliable measurement methods;competent and accurate interlaboratory test results of the material.