1、Designation:D634812(Reapproved 2020)Standard Test Method forDetermination of Gaseous Compounds by Extractive DirectInterface Fourier Transform Infrared(FTIR)Spectroscopy1This standard is issued under the fixed designation D6348;the number immediately following the designation indicates the year ofor
2、iginal 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.INTRODUCTIONThis extractive FTIR based field test method is used to quantify ga
3、s phase concentrations ofmultiple target analytes from stationary source effluent.Because an FTIR analyzer is potentiallycapable of analyzing hundreds of compounds,this test method is not analyte or source specific.Theanalytes,detection levels,and data quality objectives are expected to change for a
4、ny particular testingsituation.It is the responsibility of the tester to define the target analytes,the associated detectionlimits for those analytes in the particular source effluent,and the required data quality objectives foreach specific test program.Provisions are included in this test method t
5、hat require the tester todetermine critical sampling system and instrument operational parameters,and for the conduct ofQA/QC procedures.Testers following this test method will generate data that will allow anindependent observer to verify the valid collection,identification,and quantification of th
6、e subjecttarget analytes.1.Scope1.1 This field test method employs an extractive samplingsystem to direct stationary source effluent to an FTIR spec-trometer for the identification and quantification of gaseouscompounds.Concentration results are provided.This testmethod is potentially applicable for
7、 the determination ofcompounds that(1)have sufficient vapor pressure to betransported to the FTIR spectrometer and(2)absorb a sufficientamount of infrared radiation to be detected.1.2 This field test method provides near real time analysis ofextracted gas samples from stationary sources.Gas streamsw
8、ith high moisture content may require conditioning to mini-mize the excessive spectral absorption features imposed bywater vapor.1.3 This field test method requires the preparation of asource specific field test plan.The test plan must include thefollowing:(1)the identification of the specific targe
9、t analytes(2)the known analytical interferents specific to the test facilitysource effluent(3)the test data quality necessary to meet thespecific test requirements and(4)the results obtained from thelaboratory testing(see Annex A1 for test plan requirements).1.4 The FTIR instrument range should be s
10、ufficient tomeasure from high ppm(v)to ppb(v)and may be extended tohigher or lower concentrations using any or all of the followingprocedures:1.4.1 The gas absorption cell path length may be eitherincreased or decreased,1.4.2 The sample conditioning system may be modified toreduce the water vapor,CO
11、2,and other interfering compoundsto levels that allow for quantification of the targetcompound(s),and1.4.3 The analytical algorithm may be modified such thatinterfering absorbance bands are minimized or stronger/weakerabsorbance bands are employed for the target analytes.1.5 The practical minimum de
12、tectable concentration isinstrument,compound,and interference specific(see AnnexA2 for procedures to estimate the achievable minimum detect-able concentrations(MDCs).The actual sensitivity of theFTIR measurement system for the individual target analytesdepends upon the following:1.5.1 The specific i
13、nfrared absorptivity(signal)and wave-length analysis region for each target analyte,1.5.2 The amount of instrument noise(see Annex A6),and1.5.3 The concentration of interfering compounds in thesample gas(in particular,percent moisture and CO2),and theamount of spectral overlap imparted by these comp
14、ounds in thewavelength region(s)used for the quantification of the targetanalytes.1This test method is under the jurisdiction of Committee D22 on Air Quality andis the direct responsibility of Subcommittee D22.03 on Ambient Atmospheres andSource Emissions.Current edition approved Dec.1,2020.Publishe
15、d December 2020.Originallyapproved in 1998.Last previous edition approved in 2012 as D6348 121.DOI:10.1520/D6348-12R20.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationa
16、lly recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.1.5.4 Any sampling system interferences such as adsorptionor outgassing.1.6 Practices E168 and E1252 are suggested for additionalreading.1.7 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard
