ASTM_E_1479_-_16.pdf

Designation:E147916Standard 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 This practice describes the components of an induc-tively coupled plasma atomic emission spectrometer(ICP-AES)that are basic to its operation and to the quality of itsperformance.This practice identifies critical factors affectingaccuracy,precision,and sensitivity.It is not the intent of thispractice to specify component tolerances or performancecriteria,since these are unique for each instrument.A prospec-tive user should consult with the manufacturer before placingan order,to design a testing protocol that demonstrates 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for Fundamental Calculations to ConvertIntensities into Concentrations in Optical Emission Spec-trochemical Analysis(Withdrawn 2004)3E172 Practice for Describing and Specifying the ExcitationSource in Emission SpectrochemicalAnalysis(Withdrawn2001)3E416 Practice for Planning and Safe Operation of a Spec-trochemical Laboratory(Withdrawn 2005)3E520 Practice for Describing Photomultiplier Detectors inEmission and Absorption Spectrometry3.Terminology3.1 DefinitionsFor terminology relating to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,aradiant energy gathering optic,an entrance slit and dispersingelement to sample and isolate wavelengths of light emittedfrom the plasma,one or more devices for converting theemitted light into an electrical current or voltage,one or moreanalogpreamplifiers,oneormoreanalog-to-digitalconverter(s),and a dedicated 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 inductive energytransfer to and subsequent ionization of the gas stream con-tained in the torch.The torch is mounted centrally in a metalstructure,which is called the load coil.Energy is applied to theload 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 spark thatfunctions only during plasma ignition.4.2 When material passes through the plasma,it isvaporized,atomized,and partly ionized.The produced atomsand ions are excited into an energetically higher state.Freeatoms and ions are excited from their ground states mainly bycollision with the major plasma constituents.The excitedatoms or ions subsequently decay to a lower energy state andemit photons,some of which pass through the entrance slit of1This 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.1,2016.Published December 2016.Originallyapproved in 1992.Last previous edition approved in 2011 as E1479 99(2011).DOI:10.1520/E1479-16.2For 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 a spectrometer.Each element emits a unique set of emissionlines.Photons of a desired wavelength may be selected fromthe ultraviolet and visible spectra by means of a dispersingelement.4.2.1 Instruments may determine elements either simultane-ously or sequentially.The outp