1、Designation:G21416Standard Test Method forIntegration of Digital Spectral Data for Weathering andDurability Applications1This standard is issued under the fixed designation G214;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the yea
2、r 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 test method specifies a single relatively simplemethod to implement,common integration technique,theModified Trap
3、ezoid Rule,to integrate digital or tabulatedspectral data.The intent is to produce greater consistency andcomparability of weathering and durability test results betweenvarious exposure regimes,calculation of materials properties,and laboratories with respect to numerical results that dependupon the
4、 integration of spectral distribution data.1.2 Weathering and durability testing often requires thecomputation of the effects of radiant exposure of materials tovarious optical radiation sources,including lamps with varyingspectral power distributions and outdoor and simulated sun-light.Changes in t
5、he spectrally dependent optical properties ofmaterials,in combination with exposure source spectral data,are often used to evaluate the effect of exposure to radiantsources,develop activation spectra(Practice G178),andclassify,evaluate,or rate sources with respect to reference orexposure source spec
6、tral distributions.Another important ap-plication is the integration of the original spectrally dependentoptical properties of materials in combination with exposuresource spectral data to determine the total energy absorbed bya material from various exposure sources.1.3 The data applications descri
7、bed in 1.2 often require theuse of tabulated reference spectral distributions,digital spectraldata produced by modern instrumentation,and the integratedversion of that data,or combinations(primarily multiplication)of spectrally dependent data.1.4 Computation of the material responses to exposure tor
8、adiant sources mentioned above require the integration ofmeasured wavelength dependent digital data,sometimes inconjunction with tabulated wavelength dependent reference orcomparison data.1.5 The term“integration”in the previous sections refers tothe numerical approximation to the true integral of c
9、ontinuousfunctions,represented by discrete,digital data.There arenumerous mathematical techniques for performing numericalintegration.Each method provides different levels ofcomplexity,accuracy,ease of implementation and computa-tional efficiency,and,of course,resultant magnitudes.Hulstrom,Bird and
10、Riordan(1)2demonstrate the differencesbetween results for rectangular(963.56 W/m2),trapezoid rule(962.53 W/m2),and modified trapezoid rule(963.75 W/m2)integration for a single solar spectrum.Thus the need for astandard integration technique to simplify the comparison ofresultsfromdifferentlaboratori
11、es,measurementinstrumentation,or exposure regimes.1.6 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.7 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility
12、of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:3E275 Practice for Describing and Measuring Performance ofUltraviolet and Visible SpectrophotometersE424
13、 Test Methods for Solar Energy Transmittance andReflectance(Terrestrial)of Sheet MaterialsE490 Standard Solar Constant and Zero Air Mass SolarSpectral Irradiance TablesE772 Terminology of Solar Energy ConversionE903 Test Method for Solar Absorptance,Reflectance,andTransmittance of Materials Using In
14、tegrating SpheresE927 Specification for Solar Simulation for PhotovoltaicTestingE971 Practice for Calculation of Photometric Transmittanceand Reflectance of Materials to Solar Radiation1This test method is under the jurisdiction of ASTM Committee G03 onWeathering and Durability and is the direct res
15、ponsibility of Subcommittee G03.09on Radiometry.Current edition approved May 1,2016.Published May 2016.Originallyapproved in 2015.Last previous edition approved in 2015 as G21415.DOI:10.1520/G0214-16.2The boldface numbers in parentheses refer to a list of references at the end ofthis standard.3For r
16、eferenced 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 E972 Test Method for Solar Photometric Transmittance ofSheet Materials Using SunlightE973 Test Method for Determination of the Spectral Mis-match Parameter Betwee
