ASTM_E_1479_-_99_2011.pdf

Designation:E147999(Reapproved 2011)Standard Practice forDescribing and Specifying Inductively-Coupled PlasmaAtomic Emission Spectrometers1This standard is issued under the fixed designation E1479;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 Thispracticedescribesthecomponentsofaninductively-coupled plasma atomic emission spectrometer(ICP-AES)that are basic to its operation and to the quality ofits performance.This practice identifies critical factors affect-ing accuracy,precision,and sensitivity.It is not the intent ofthis practice to specify component tolerances or performancecriteria,since these are unique for each instrument.A prospec-tive user should consult with the vendor before placing anorder,to design a testing protocol to demonstrate that theinstrument meets all anticipated needs.1.2 The values stated in SI units are to be regarded asstandard.The values given in parentheses are for informationonly.1.3 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility 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.Specific safetyhazard statements are given in Section 13.2.Referenced Documents2.1 ASTM Standards:2E135 Terminology Relating to Analytical Chemistry forMetals,Ores,and Related MaterialsE158 Practice for Fundamental Calculations to ConvertIntensities into Concentrations in Optical Emission Spec-trochemical Analysis(Withdrawn 2004)3E172 Practice for Describing and Specifying the ExcitationSource in Emission SpectrochemicalAnalysis(Withdrawn2001)3E416 Practice for Planning and Safe Operation of a Spec-trochemical Laboratory(Withdrawn 2005)3E520 Practice for Describing Photomultiplier Detectors inEmission and Absorption Spectrometry3.Terminology3.1 DefinitionsFor terminology relating to emissionspectrometry,refer to Terminology E135.4.Summary of Practice4.1 An ICP-AES is an instrument used to determine elemen-tal composition.It typically is comprised of several assembliesincluding a radio-frequency(RF)generator,an impedancematching network(where required),an induction coil,a plasmatorch,a plasma ignitor system,a sample introduction system,alight gathering optic,an entrance slit and dispersing element tosample and isolate wavelengths of light emitted from theplasma,one or more devices for converting the emitted lightinto an electrical current or voltage,one or more analogpreamplifiers,one or more analog-to-digital converter(s),and adedicated computer with printer(see Fig.14).4.1.1 The sample is introduced into a high-temperature(6000 K)plasma that is formed from the ionization of the gasstream contained in the torch.The torch is inserted throughmetal tubing formed into a helix,which is called the load coil.Energy is applied to the load coil by means of an RF generator.4.1.2 The term inductively-coupled refers to the fact that thephysical phenomenon of induction creates a plasma by trans-ferring energy from the load coil to the gas stream that has beenmomentarily preionized by a high voltage ignitor electrode thatfunctions only during plasma ignition.4.2 When material passes through the plasma,it isvaporized,atomized,and many elements are almost completelyionized.Free atoms and ions are excited by collision from theirground states.When the excited atoms or ions subsequentlydecay to a lower energy state,they emit photons,some ofwhich pass through the entrance slit of a spectrometer.Eachelement emits a unique set of emission lines.Photons of adesired wavelength may be selected from the ultraviolet andvisible spectra by means of a dispersing element.1This practice is under the jurisdiction of ASTM Committee E01 on AnalyticalChemistry for Metals,Ores,and Related Materials and is the direct responsibility ofSubcommittee E01.20 on Fundamental Practices.Current edition approved Nov.15,2011.Published June 2012.Originallyapproved in 1992.Last previous edition approved in 2005 as E1479 99(2005).DOI:10.1520/E1479-99R11.2For 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.3The last approved version of this historical standard is referenced onwww.astm.org.4Courtesy of PerkinElmer,Inc.,761 Main Ave.,Norwalk,CT 06859.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 4.2.1 Instruments may determine elements either simultane-ously or sequentially.The output of the detector generally isdirected to a preamplifier,an analog-to-digital converter,and acomputer whic