Certified standard, defined

Let us begin with the ISO definition [9] A calibration is a set of operations that establish, under specified conditions, the relationship between values of quantities indicated by a measuring instrument or measuring system, or values represented by a material measure or reference material, and the corresponding values realized by standards. Applied to amount measurements, the standards would then be the values assigned to the RMs (of defined composition) at the stated uncertainty relative to the true value of the property, expressed in SI units, or relative to an internationally recognized, certified standard RM for the relevant property, range, and matrix composition. 

Ashing of samples may be defined as heating a substance to leave an ash that is noncombustible and that is soluble in most dilute acid or base solutions. The resulting solution is analysed for elemental composition against certified standards prepared in the same acid... 

A. 2 Yes. Under 1926.403(a), all electrical conductors and equipment must be approved. The standard defines approved as acceptable. With regard to your equipment, acceptable means accepted, or certified, or listed, or labeled, or otherwise determined to be safe by a qualified testing laboratory capable of determining the suitability of materials and equipment for installation and use... 

DaimlerChrysler requires that its suppliers be certified to the automobile industry s quality standard, called QS-9000. That standard defines the internal quality processes that suppliers must use. An independent registrar must certify compliance with these processes. They cover continuous improvement, defect prevention, and reduction in variation. QS-9000 provides a foundation of basic requirements for any supplier wanting to serve any of the major automobile companies. 

Patent laws provide for several stages in the life of an application for a patent on an invention. The pattern followed by patent laws in effect in most industrialized countries during the nineteenth and early twentieth centuries, and still in effect in the United States in 1995, calls for the examination of all patent appHcations to certify that the claimed invention meets the national standards for novelty, usehilness, and inventiveness. The owner of the technology to be patented files appHcation papers that include a specification containing a description of the invention to be patented (called the disclosure) and claims defining the limits of the invention to be protected by the patent, a formal request for the issuance of a patent, and fees. Drawings of devices and apparatuses, electrical circuits, flow charts, etc, are an important part of the disclosures of most nonchemical and many chemical patents. 

In analytical chemistry, we do not have a standard mole. Therefore, solutions made up to a well-defined concentration using very pure chemicals are used as a basis from which we can compare other solutions or an instrument scale. This process is calibration . For some analyses, the chemical used may be a Certified Reference Material which has a well documented specification, e.g. in terms of the concentration of a particular species and the uncertainty of the specified value. However, it is not sufficient just to calibrate the apparatus/equipment used, it is important that the complete method of analysis is validated from extraction of the analyte from the sample to the final measurement. 

One or more of these bias components are encountered when analyzing RMs. In general, RMs are divided into certified RMs (CRMs, either pure substances/solu-tions or matrix CRMs) and (noncertified) laboratory RMs (LRMs), also called QC samples [89]. CRMs can address all aspects of bias (method, laboratory, and run bias) they are defined with a statement of uncertainty and traceable to international standards. Therefore, CRMs are considered useful tools to achieve traceability in analytical measurements, to calibrat equipment and methods (in certain cases), to monitor laboratory performance, to validate methods, and to allow comparison of methods [4, 15, 30]. However, the use of CRMs does not necessarely guarantee trueness of the results. The best way to assess bias practically is by replicate analysis of samples with known concentrations such as reference materials (see also Section 8.2.2). The ideal reference material is a matrix CRM, as this is very similar to the samples of interest (the latter is called matrix matching). A correct result obtained with a matrix CRM, however, does not guarantee that the results of unknown samples with other matrix compositions will be correct [4, 89]. 

What does optimization mean in an analytical chemical laboratory The analyst can optimize responses such as the result of analysis of a standard against its certified value, precision, detection limit, throughput of the analysis, consumption of reagents, time spent by personnel, and overall cost. The factors that influence these potential responses are not always easy to define, and all these factors might not be amenable to the statistical methods described here. However, for precision, the sensitivity of the calibration relation, for example (slope of the calibration curve), would be an obvious candidate, as would the number of replicate measurements needed to achieve a target confidence interval. More examples of factors that have been optimized are given later in this chapter. 

In the USA, for Tier 2 emission limits different bins have been defined. Passenger cars are certified in any of the available bins by choice of the vehicle manufacturer. With full implementation in 2009, the average NOx emission of the entire light-duty fleet sold by each manufacturer must meet 0.07 g/mile. For the individual bins, the full useful life emission limits are displayed in Table I. The very strict California low emission vehicle (LEV) II emission standards are covered in the lower number bins to make certification easier for vehicle manufacturers. 

Quantification of Analytical Data via Calibration Curves in Mass Spectrometry Using Certified Reference Materials or Defined Standard Solutions... 

The documentation requirements are fulfilled in accordance with international standard ISO 9001 2000. The documentation includes information describing, defining, specifying, reporting, or certifying activities, requirements, procedures, or results. 

Accuracy and Interpretation of Measured pH Values. To define the pH scale and pertnil the calibration of pH measurement systems, a scries of reference buffer solutions have been certified hy the U.S. National Institute of Standards and Technology iNIST). The acidity function which is the experimental basis for the assignment of pH. is reproducible within about O.IKl.I pH unit from It) to 40T. However, errors in the standard potential of the cell, in the composition of the buffer materials, and in the preparation of the solutions may raise the uncertainty to 0 005 pH unit. The accuracy of ihe practical scale may he furthei reduced to (I.Ot)X-(l.(ll pH unit as a result of variations in the liquid-junction potential. 

CRMs allow the user to link his results with those of internationally recognised standards, i.e. they enable the user to verify his performance at any desired moment in terms of accuracy. CRMs can be pure substances or solutions to be used for calibration and/or identification, materials of a known matrix composition for the calibration of a certain type of comparative measuring instruments, matrix RMs representing as far as possible the matrix being analysed by the user (with a certified content), or methodologically defined RMs (certified following a very strict analytical protocol), e.g. a standard (Quevauviller et al., 1995a). 

Use of reference materials traceable to SI. In the majority of measurements, the certified reference materials (CRM) traceable to SI are by far the best definable reference points and they are most frequently used as measurement standards in chemical and other measurements. These materials are the means of achieving reliable measurements and they are available from the internationally recognized organizations for a wide range of users. 

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