ASTM_E_1421_-_99_2015e1.pdf

Designation:E142199(Reapproved 2009)Standard Practice forDescribing and Measuring Performance of FourierTransform Mid-Infrared(FT-MIR)Spectrometers:Level Zeroand Level One Tests1This standard is issued under the fixed designation E1421;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This practice describes two levels of tests to measure theperformance of laboratory Fourier transform mid-infrared(FT-MIR)spectrometers equipped with a standard sampleholder used for transmission measurements.1.2 This practice is not directly applicable to Fourier trans-form infrared(FT-IR)spectrometers equipped with variousspecialized sampling accessories such as flow cells or reflec-tance optics,nor to Fourier transform near-infrared(FT-NIR)spectrometers,nor to FT-IR spectrometers run in step scanmode.1.2.1 If the specialized sampling accessory can be removedand replaced with a standard transmission sample holder,thenthis practice can be used.However,the user should recognizethat the performance measured may not reflect that which isachieved when the specialized accessory is in use.1.2.2 If the specialized sampling accessory cannot beremoved,then it may be possible to employ a modified versionof this practice to measure spectrometer performance.The useris referred to Guide E1866 for a discussion of how these testsmay be modified.1.2.3 Spectrometer performance tests for FT-NIR spectrom-eters are described in Practice E1944.1.2.4 Performance tests for dispersive MIR instruments aredescribed in Practice E932.1.2.5 For FT-IR spectrometers run in a step scan mode,variations on this practice and information provided by theinstrument vendor should be used.2.Referenced Documents2.1 ASTM Standards:2E131 Terminology Relating to Molecular SpectroscopyE932 Practice for Describing and Measuring Performance ofDispersive Infrared SpectrometersE1866 Guide for Establishing Spectrophotometer Perfor-mance TestsE1944 Practice for Describing and Measuring Performanceof Laboratory Fourier Transform Near-Infrared(FT-NIR)Spectrometers:Level Zero and Level One Tests3.Terminology3.1 DefinitionsFor definitions of terms used in thispractice,refer to Terminology E131.All identifications ofspectral regions and absorption band positions are given inwavenumbers(cm1),and spectral energy,transmittance,andabsorbance are signified in equations by the letters E,T,and Arespectively.The ratio of two transmittance or absorbancevalues,and the ratio of energy levels at two different wave-numbers are signified by the letter R.A subscripted numbersignifies a spectral position in wavenumbers(for example,A3082,the absorbance at 3082 cm1).3.1.1 level one(1)test,na simple series of measurementsdesigned to provide quantitative data on various aspects ofinstrument performance and information on which to base thediagnosis of problems.3.1.2 level zero(0)test,na routine check of instrumentperformance,that can be done in a few minutes,designed tovisually detect significant changes in instrument performanceand provide a database to determine instrument function overtime.4.Significance and Use4.1 This practice permits an analyst to compare the generalperformance of an instrument on any given day with the priorperformance of an instrument.This practice is not necessarilymeant for comparison of different instruments with each othereven if the instruments are of the same type and model.Thispractice is not meant for comparison of the performance of oneinstrument operated under differing conditions.5.Test Conditions5.1 Operating ConditionsA record should be kept todocument the operating conditions selected so that they can be1This practice is under the jurisdiction of ASTM Committee E13 on MolecularSpectroscopy and Separation Science and is the direct responsibility of Subcom-mittee E13.03 on Infrared and Near Infrared Spectroscopy.Current edition approved March 1,2009.Published March 2009.Originallyapproved in 1991.Last previous edition approved in 2004 as E1421 99(2004).DOI:10.1520/E1421-99R09.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 duplicated.In obtaining spectrophotometric data,the analystmust select proper instrumental operating conditions such aswarm-up time,purge rate,and beam splitter alignment in orderto realize satisfactory instrument performance.Operating con-ditions for individual instruments are best obtained from themanufacturers literature because of variations with instrumentdesign.It should be noted that many FT-IR instr