1、Designation: E 2161 08Standard Terminology Relating toPerformance Validation in Thermal Analysis1This standard is issued under the fixed designation E 2161; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision.
2、 A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 Validation of methods and apparatus is requested orrequired for quality initiatives or where results may be used forlegal purposes.
3、1.2 This standard provides terminology relating to validat-ing performance of thermal analysis methods and instrumen-tation. Terms that are generally understood or defined ad-equately in other readily available sources are not included.1.3 The terminology described in this document is that ofthe val
4、idation process and may differ from that traditionallyencountered in ASTM standards.1.4 A definition is a single sentence with additional infor-mation included in a Discussion.2. Terminologyaccuracythe agreement between an experimentally deter-mined value and the accepted reference value.DISCUSSIONA
5、ccuracy is also known as bias in ASTM practice.analytethe specific component measured in an analysis.baselinethe resultant analytical trace when no test specimenis present.blankthe measured value obtained when a specific compo-nent is not present during the measurement.bowthe maximum deviation betwe
6、en an actual instrumentreading and the reading predicted by a straight line drawnbetween upper and lower calibration points, expressed as apercent of full scale.calibrationto check, adjust, or systematically standardizethe gradations of a quantitative measuring signal.certificatea formal document te
7、stifying to the truth of amatter (see also certification).certificationprocess of issuing a formal document testifyingto the truth of a matter.NOTE 1 Includes conditions (such as accreditation), materials (suchas reference materials), processes (such as calibration), and the like.certified reference
8、 materiala reference material lot, theproperty(ies) of which, determined by measurement is/arecertified by an identified organization and found on anaccompanying certificate.NOTE 2Each certified value should be is accompanied by an uncer-tainty at a stated level of confidence.coefficient or variatio
9、nthe standard deviation divided by thevalue of the parameter measured.conformanceagreement of a product, process or servicewith specification requirements.detection limitthe minimum quantity of analyte that can bereliably detected but not necessarily quantified.driftthe relatively slow change in bas
10、eline output due toinstrument performance taken to be the maximum deviationbetween any two points within a specified time period.figure-of-merita performance characteristic of a methodbelieved to be useful when deciding its applicability for aspecific measurement situation.DISCUSSIONTypical figures-
11、of-merit include accuracy, repeatability,sensitivity, etc.full-width at half- maximum (FWHM), nthe differencebetween the two extreme values of a peak of the independentvariable at which the dependent variable is equal to half ofits maximum value.linearitythe maximum deviation of output points from t
12、he“best fit” linear curve to the data excluding proven outliersexpressed as a percentage of the full-scale computed output.noisethe maximum amplitude, peak-to-peak, for all randomvariations.noise, short termis that with a frequency greater than sixcycles per min (equivalent to a period of 10 seconds
13、 or less).DISCUSSIONShort Term Noise determines the smallest signal detect-able and limits the precision attainable in quantitation of low levelmeasurements.noise, long termis that with a frequency between 0.6 and6 cycles per min (equivalent to periods of 100 and 10 s).DISCUSSIONLong Term Noise may
14、be mistaken for the response ofa test specimen.precisionthe degree of agreement among or between re-peated measurements of the same property.quantitation limitthe minimum amount that can be quanti-fied with acceptable accuracy and precision.1This terminology is under the jurisdiction of ASTM Committ
15、ee E37 onThermal Measurements and is the direct responsibility of Subcommittee E37.03 onNomenclature and Definitions.Current edition approved May 1, 2008. Published May 2008. Originallyapproved in 2001. Last previous edition approved in 2007 as E 216107a.1Copyright ASTM International, 100 Barr Harbo
16、r Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.reference materiala material or substance, the property forwhich is sufficiently homogeneous and well established to beused for the calibration of apparatus, or the assessment of ameasurement method.relative standard deviationthe
17、coefficient of variation ex-pressed as a percentage.repeatabilitya quantitative measure of the precision of theresults by a single analyst in a given laboratory using a givenapparatus.reproducibilitya quantitative measure of the precision ofthe results between two laboratories.resolutiona quantitati
18、ve measure of the ability to separateclosely spaced transitions at an appropriate analytic level.DISCUSSIONResolution is one component of selectivity.selectivitythe ability to accurately and specifically measurethe analyte in the presence of components that may beexpected to be present in the test s
19、pecimen.sensitivitythe capability of methodology or instrumentationto discriminate between samples having differing concentra-tions or containing differing amounts of an analyte.DISCUSSIONDetection Limit and Quantitation Limit are indicatorsof sensitivity.slopethe ratio of rise (change in Y-axis) to
20、 run (change inX-axis) for a linear curve or tangent to a point on anon-linear curve.standard deviationa measure of variation or scatter aroundthe arithmetic average or mean.standard reference materiala certified reference material,one or more properties of which have been certified by anational met
21、rology institute.NOTE 3Each certified value is should be accompanied by an uncer-tainty at a stated level of confidence.time constanta measure of the rapidity of response of asystem.DISCUSSIONThe time constant is a measure of an instrumentsability to respond to a signal and limits resolution. The sh
22、orter the timeconstant, the better the resolution.validationthe process of providing documented evidencethat something does what it is intended to do.2.1 Terminology commonly used in the study of precisionand bias, in thermal analysis, and thermophysical propertiesmay be found in ASTM terminology st
23、andards E 177, E 473,and E 1142. Additional information on method validation maybe found in the US Pharmacopeia and National Formulary,United States Pharmacopeial Convention, Inc. 12601 Twin-brook Parkway, Rockville, MD 20852.ASTM International takes no position respecting the validity of any patent
24、 rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at
25、 any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comment
26、s will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted b
27、y ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).E2161082
