Calibration history

Instrument calibrations are required at intervals based on the criticality of the instruments, instrument capability, and instrument calibration history. An instmment will also be calibrated following the repair of the instrument, following the repair of the system that the instrument is monitoring/controlling, if the repair could have affected the instrument accuracy, and/or after installing the instmment into a system. All equipment used to perform calibrations will be calibrated to standards traceable to the National Institute of Standards and Technology (NIST) or other approved standards and maintain the following ... 

Complete records of all calibrations should be maintained. This must include unique identification of each item of instrumentation, its location within the aseptic manufacturing facility, and its calibration history and evidence of its traceability to recognized standards. 

The cahbration records referred to in para. 9.42(4) should provide a calibration history showing cahbration intervals, the date of the last cahbration, the date when the next cahbration is due, conformance or non-conformance with required tolerances before and after adjustments, and any limitations on use. It is often desirable to affix a sticker directly to the test equipment, giving the date of the last calibration and the planned date of the next cahbration. 

Known samples should also be run to verify the accuracy and precision of the routine methods to be used during the unit test. Poor quality will manifest itself as poor precision, measurements inconsistent with plant experience or laboratory history, and disagreement among methods. Plotting of laboratory analysis trends wiU help to determine whether calibrations are drifting with time or changing significantly. Repeated laboratory analyses will establish the confidence that can be placed in the results. 

R.E. Taylor, History of radiocarbon dating, lecture presented at Radiocarbon in ecology and earth system science (http //ecology/botany/ufl/radiocarbon07/), University of California, Irvine (2006). (The first radiocarbon revolution is represented by the development of the dating method by Libby and his colleagues the second radiocarbon revolution is considered to be the introduc tion of calibration.)... 

One of the most interesting of the geophysics results from radiocarbon dates is the history of the sun. Apparently, it is registered in fluctuations of the cosmic ray intensity. These are fluctuations of rather short duration in terms of the radiocarbon lifetime, perhaps a century or so, and apparently they are caused by variations in the solar wind due to long-term changes in the solar emissions. This idea has been developed in some detail recently by Dr. Lai and his collaborators. It promises to give us a way of watching the history of the sun over tens of thousands of years. This fine structure on the curve of calibration was discovered by Dr. Suess and others. 

The shape function had a role in theoretical chemistry and physics long before it was named by Parr and Bartolotti. For example, in x-ray measurements of the electron density, what one actually measures is the shape function—the relative abundance of electrons at different locations in the molecule. Determining the actual electron density requires calibration to a standard with known electron density. On the theoretical side, the shape function appears early in the history of Thomas-Fermi theory. For example, the Majorana-Fermi-Amaldi approximation to the exchange potential is just [3,4]... 

Morgan TA. History of dissolution calibration. Dissolution Technol 1995 2(4) 3—9. 

Everything suggests that the Fe/H ratio can be taken as a kind of chronometer, or at least as an index of evolution. It defines the chemical history of the Galaxy, and cannot decrease. The accumulation of iron in the interstellar medium is such that the abundance of this element increases monotonically, although in a way that is far from linear. The Fe/H ratio can be calibrated as a function of time by jointly determining the iron content and age of a great many stars selected from distinct generations. This then constitutes the basis of the age-metallicity relation. 

REST need not necessarily involve any animals at all. If electronic sensors of adequate sensitivity are developed, they can replace the animals. Certainly, the history of electronic instrument development shows that the earlier generations of any device are more suited for laboratory than field use, and that laboratory units can normally be expected to show better performance than portable ones. Calibration of an electronic instrument, which corresponds to training of a mammal, should become more precise and dependable than that training. 

The area of a DSC peak can be used to estimate the enthalpy of transition, AH, provided the thermal history of the sample is considered [29]. Calibration with respect to enthalpy requires an area that corresponds to a well-defined enthalpy change—a heat of fusion AH(Tm) is commonly used, especially that of indium [3]. 

When making a chemical measurement by taking a certain amount of the test material, working it up in a form that can be analyzed, calibrating the instrument, and performing the measurement, analysts understand that there will be some doubt about the result. Contributions to uncertainty derive from each step in the analysis, and even from the basis on which the analysis is carried out. An uncertainty budget documents the history of the assessment... 

Figure 11. Hustedt pH categories (26), diatom-inferred pH values (weighted averaging), calibration radiocarbon dates, 210Pb dates, and pH periods in the history of Lilia Oresjon, southwest Sweden. Each bar and point represents one of the 700 samples analyzed from each 0.5-cm interval from the 350-cm-long core. (Reproduced with permission from reference 68. Copyright 1990 Royal Society of London.)...

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