Traceability meaning

Traceability of measurement results is essential in the establishment of a certified reference material. As stipulated in ISO Guides 30 and 35, a certified reference material can only be certified if there is an uncertainty statement with a traceability statement. Basically, traceability means anchoring. In classical analytical chemistry, that SI system is often the best choice as a reference (= anchoring poinf). However, there is a wide range of parameters either defined by a method or defined by the... 

Traceability means that the process steps as well as the output(s) can be traced back to actual customer requirements. 

Abstract Talking about traceability means talking about a property of the result of a measurement , about the value of a standard , about stated references and about an unbroken chain of comparisons . It describes by which comparison, and to which other value, the result of a measurement has been obtained, i.e. is traceable to . It is about the underlying structure of the measurement process of the result of a measurement and therefore about the authority of the result. Since values carried by (certified) reference materials have also been obtained by measurement, the definition of traceability equally applies. Traceability in the context of reference materials is also about the authority of the values carried by the (certified) reference materials and is, therefore, of key importance for the authority of the reference materials themselves. Hence, values of results of measurements constitute part of the traceability chain and their uncertainties are an intrinsic accompanying phenomenon. Uncertainties need a traceability chain against which they can be evaluated, and a traceability chain is an... 

The topic is complex with many interrelated strands. Despite successes, there remains some confusion in the debate and little clear guidance on how you actually achieve traceability in a practical way. Paradoxically, there is both loose talk about what traceability means and a lack of recognition of the many elements of traceability that already exist. The definition of traceabili-... 

The increased attention paid to the concept of traceability and its implementation in the world of chemical measurements has been one of the major goals of metrological activity in recent years. In Romania traceability of chemical measurement has been closely connected with the accreditation of analytical chemistry laboratories. However, this concept has only recently been adopted in this country for clinical measurements. Within this framework an attempt is made to review what traceability means in terms of clinical measurements and what is now being done by the Romanian National Institute of Metrology (INM) to develop the principles of traceability in spectrophotometrical measurements performed in clinical chemistry laboratories. 

Do not pay by a traceable means -- e.g., personal check or wire-transfer. 

In a nutshell, "traceability" means that analytical results, such as the concentration of a drug metabolite in urine, can be linked, related, or traced to an unassailable original source, such as an NIST SRM. Traceability is also interpreted more broadly to include the calibration of instrumentation and equipment. For example, analytical balances can be calibrated witii certified weights that are traceable to NIST standard weights. Traceability can be thought of as a chain of custody for quality Data that are traceable can be linked to reliable sources through what may be a long, but unbroken, documented chain of relationships and dependencies. Ideally, the calibration and performance of every piece of laboratory equipment... 

It may be realised by means of definite complex of intereonneeted and interrelated common rules and norms direeted to the assurance of traceability and uniformity of measuring equipment, NDT equipment including. In another words NDT equipment must be metrologically supported. 

Collaborative testing provides a means for estimating the variability (or reproducibility) among analysts in different labs. If the variability is significant, we can determine that portion due to random errors traceable to the method (Orand) and that due to systematic differences between the analysts (Osys). In the previous two sections we saw how a two-sample collaborative test, or an analysis of variance can be used to estimate Grand and Osys (or oJand and Osys). We have not considered, however, what is a reasonable value for a method s reproducibility. 

Head. The tme meaning of the total developed pump head, H, is the amount of energy received by the unit of mass per unit of time (14). This concept is traceable to compressors and fans, where engineers operate with enthalpy, a close relation to the concept of total energy. However, because of the almost incompressible nature of Hquids, a simplification is possible to reduce enthalpy to a simpler form, a Bernoulli equation, as shown in equations 1—3, where g is the gravitational constant, SG is specific gravity, y is the density equivalent, is suction head, is discharge head, and H is the pump head, ie, the difference between H, and H. 

The standard also requires that the instructions be derived from appropriate sources, such as the quality plan, the control plan, and the product realization process, which means that all instructions should be traceable to one or more of these documents. They should form a set, so that there are no instructions used outside those that have been approved by the planning team. This is to ensure that no unauthorized practices are employed. Another important aspect to consider is the use of informal practices - practices known only to the particular operator. Process capability should be based on formal routines, otherwise repeatability cannot be assured when operators change. 

It would be considered prudent to prohibit the premature release of product if you did not have an adequate traceability system in place. If in fact any nonconformities in a component will be detected by the end product tests, it may be worth allowing production to commence without the receipt tests being available, in which case the tests will only be confidence checks and not verification checks. If only one product is received and released prior to verification one would think that, as the requirement applies prior to verification, there is no need to positively identify the product to permit recall because you would know where it was if you found it to be nonconforming. However, the nonconformity may have been reported to you by the supplier after delivery. The standard does not stipulate when and by whom the nonconformity may have been detected. If you lose the means of determining conformity by premature release, don t release the product until you have verified it is acceptable. 

This requirement is similar to that stated in clause 4.11.2 of the standard and addressed later in this chapter. The checks and rechecks required to prove that the software is capable of verifying the acceptability of product are a means of calibrating test software. However, test software does not wear or drift with age or use and so cannot be calibrated against a standard traceable to national standards. To control test software you need to consider what it is that you need to control. As a minimum you should control its use, modification, location (in terms of where it is installed), replication, and disposal. Requirements for other controls are covered in clause 4.11.2 of the standard, where they can be applied to test software. 

Aim To measin e the binding of a radioligand (or ligand that is traceable by other means) to a receptor. The object is to obtain an estimate of the equilibrium dissociation constant of the radioligand-receptor complex (denoted Kd) and the maximal number of binding sites (denoted Umax)-... 

The assessment of the performance of a method is commonly checked by means of a (C)RM. In those cases where there is no RM available, considerable effort is requested from the laboratory to assess the performance of their own methods. The aspect of traceability of the certified value(s) is also of great importance whenever necessary, the laboratory will make modifications in its procedures if the result of a measurement using the RM appears to be imsatisfactory. If the traceabihty of the values to other references is not fully established, then this judgement may be clouded by doubts about the certified value (s). 

Another aspect of traceability of the results is the linkage of data from the homogeneity study, the stability study, and the characterization study of the reference material. In order to establish this link, the coordinator must be in the position to demonstrate that the results of these three studies have a common reference. Such a reference can be a calibrant, reference material, or possibly some realization by means of a suitable method. If such a common reference is not available, it is impossible to link the data sets, and therefore it is impossible to translate the results from the homogeneity and stability studies to the characterization of the material. 

All values of the IRMM Isotopic Reference Materials are traceable to the SI (the international system of base quantities and base units). Isotopic measurement results corrected by means of these Isotope Ratio Reference Materials have reduced (ISO/BIPM) uncertainties. Isotopic measruements carried out against these Spike Reference Materials are traceable to the SI, if carried out properly. Further details are available from IRMM website see Chapter 8. 

By means of LIMS the reliability of the tests, the traceability of the results, and the security of the data can be guaranteed. In addition, the effectivity of the costs may be estimated and supply, service and maintenance of instruments managed. LIMS always has to be designed in an individual way according to its specific profile. Information on LIMS can be found mainly on the internet (see Limsource, Lapitajs and Klinkner, etc.). 

The coordinated approach contracting relationships built on collaboration, trust and close interpersonal ties define the coordinated approach. This approach means that the producer inherits the responsibility and costs of social auditing as they are passed down the supply chain. This is achieved, however, within the framework of close retailer-supplier relationships. Although subcontracting exists, known networks of traceable suppliers are involved. As such, it is possible to exert considerably greater control over the ethical trading process. 

The benefits of producing good data are therefore broad and impinge on all of our daily lives, whether it is food, environment, health or trade. Laboratories that produce valid measurements have a higher status in the analytical world, since they produce data that are demonstrably traceable to a reference standard and reliable, with the cost of correcting bad data being lower. This means that such laboratories have a better chance of competing in the open market. 

In conclusion, one must insist on the importance of the main metrological characteristic, the traceabilility (generally of a result), ensuring a clear (unbroken) relationship between the final result and the complete measurement scheme by using appropriate procedures, standards and calibrated equipment. However, for chemical metrology and particularly for on-site measurement, some adaptations are needed for a wider meaning of traceability [66]. 

Pattern 6.5, Recursive Refinement The ideas of refinement apply at all levels, from describing organizations and business processes to program code. This means that it can form the single consistent basis for traceability. 

SRM stands for standard reference material. It is a standard chemical manufactured and certified by the National Institute of Standards and Technology (NIST) as being exactly as labeled. It is the ultimate standard. CRM stands for certified reference material. It is a standard chemical manufactured and certified by a vendor as being exactly as labeled. It is traceable to a SRM, meaning it has been compared to and certified with the use of an ultimate standard. 

There is often some confusion between the terms standards and reference materials. Primary standards represent the top-tier of chemical standards and, in principle, provide a means of establishing the traceability of analytical data to the SI measurement units (e.g., the kilogram, mole, meter, and second). A limited number of pure chemicals are recognized as primary standards (and thus can constitute certified reference materials). Most certified reference materials are not of themselves primary standards rather, the property values assigned to them are traceable to primary standards where practical. 

The highest quality reference materials are certified for the concentration values of the constituent(s) of interest, reflecting high confidence in the value s accuracy and the thorough investigation of all known or suspected sources of bias. Used appropriately (e.g., Roper et al., 2001 Zschunke, 2000), these certified values provide an effective means to ensure comparability (both among laboratories and over time). It is not always practical, however, to undertake the work required to produce a certified value in many such cases, a value can be carefully determined, but insufficient information exists to assess the associated uncertainty. This information value is nevertheless of substantial interest to other users of the reference material. It can, for example, allow laboratories to compare results even though full traceability is impractical. 

Note A certified" standard essentially means that the source of a component in a test standard is traceable to it s origin, that the component s identification is assured and, when applicable, that the component s quantity or concentration in the standard, as obtained, is documented. The formal document certifying the above is often called a certificate of analysis. ... 

In the above discussion, standard reference materials (SRMs) were mentioned often. A reference material (RM) is a material or substance suitable for use in calibrating equipment or standardizing solutions. A certified reference material (CRM) that a vendor indicates, via a certificate, is an RM. A standard reference material (SRM) is one that is distributed and certified by a certifying body, such as NIST. The SRM is the material to which all calibration and standardization materials should be traceable. A standard material becomes one when it is compared to or prepared from another. Ultimately, it all rests on the SRM — meaning all standard materials are traceable to an SRM (see Figure 5.10). 

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