ASTM_D_7614_-_12.pdf

Designation:D761412Standard Test Method forDetermination of Total Suspended Particulate(TSP)Hexavalent Chromium in Ambient Air Analyzed by IonChromatography(IC)and SpectrophotometricMeasurements1This standard is issued under the fixed designation D7614;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 test method specifies a procedure for the samplingand analysis of airborne particulate matter for hexavalentchromium in ambient air samples.1.2 The method involves drawing 21.6 m3ambient air(at 15L/min for 24 hours)through a sodium bicarbonate celluloseacid washed filter.Atmospheric hexavalent chromium is stabi-lized on the alkaline coated filter.1.3 This method uses ion chromatography with post-columnderivatization with 1,5-diphenylcarbazide(DPC)and aUltraviolet/Visible(UV/VIS)detector.1.4 This method is applicable to the determination ofmasses of 0.10 to 20.0 ng of hexavalent chromium per samplewithout dilution.1.5 This method is applicable for hexavalent chromiummeasurement in the atmosphere from 0.004 ng/m3to 0.926ng/m3assuming a 21.6 m3sample volume.The range can beincreased using appropriate dilutions.1.6 Interconversion of trivalent and hexavalent chromiumduring sampling is minimized to the extent possible by usingthese sampling procedures.1.7 The corresponding method for workplace air samples isASTM Test Method D6832.1.8 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.9 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.2.Referenced Documents2.1 ASTM Standards:2D4840 Guide for Sample Chain-of-Custody ProceduresD1193 Specification for Reagent WaterD1356 Terminology Relating to Sampling and Analysis ofAtmospheresD1357 Practice for Planning the Sampling of the AmbientAtmosphereD3195 Practice for Rotameter CalibrationD3586 Test Method for Chromium in Workplace Atmo-spheres(Colorimetric Method)(Withdrawn 1990)3D5281 Test Method for Collection and Analysis of Hexava-lent Chromium in Ambient Atmospheres(Withdrawn2014)3D6832 Test Method for the Determination of HexavalentChromium in Workplace Air by Ion Chromatography andSpectrophotometricMeasurementUsing1,5-diphenylcarbazide3.Terminology3.1 DefinitionsFor definitions of terms used in this testmethod,refer to Terminology D1356.3.2 Definitions of Terms Specific to This Standard:3.2.1 eluentthe mobile phase used to transport the samplethrough the ion exchange column.3.2.2 resolutionthe ability of a column to separate con-stituents under specified test conditions.4.Summary of Test Method(1,2,3,4)44.1 A known volume of air is drawn through a sodiumbicarbonate coated cellulose filter at a rate of 9.0 to 16.0 L/minfor 24 hours.1This test method is under the jurisdiction of ASTM Committee D22 on AirQuality and is the direct responsibility of Subcommittee D22.03 on AmbientAtmospheres and Source Emissions.Current edition approved April 1,2012.Published May 2012.DOI:10.1520/D7614-12.2For 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.4The boldface numbers in parentheses refer to a list of references at the end ofthis standard.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 4.2 After sampling,the chain-of-custody forms are appro-priately labeled and the filters are placed in a cooler with ice forshipment to the laboratory.Upon receipt,the filters are placedin a freezer before preparation for analysis.4.3 The filters are extracted in sodium bicarbonate by meansof sonication for one hour.The extract is analyzed by ionchromatography using a system comprised of a guard column,an analytical column,a post-column derivatization module,and a UV/VIS detector.In the analysis procedure,hexavalentchromium exists as chromate due to the near neutral pH of theeluent.After separation through the column,the hexavalentchromium forms a complex with the 1,5-diphenylcarbazide(DPC)which can be detected at 530 nm.4.4 One blank filter,per 10 samples prepared,is alsodesorbed and analyzed in accordance with 4.3.4.5 Hexavalent chromium is identified and quantified bycomparing its retention time and peak area to the correspond-ing standard solutions.5.Significance and Use5.1 Hexavalent chromium is anthropogenic from a numberof c