ASTM_D_3824_-_12.pdf

Designation:D382412Standard Test Methods forContinuous Measurement of Oxides of Nitrogen in theAmbient or Workplace Atmosphere by theChemiluminescent Method1This standard is issued under the fixed designation D3824;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 These test methods cover procedures for the continuousdetermination of total nitrogen dioxide(NO2)and nitric oxide(NO)as NOx,or nitric oxide(NO)alone or nitrogen dioxide(NO2)alone,in the ranges shown in the following table:Range of ConcentrationGasAmbient AtmosphereWorkplace Atmosphereg/m3(ppm)(Note 1)mg/m3(ppm)(Note 1)NO10 to 600(0.01 to 0.5)0.6 to 30(0.5 to 25)(NO+NO2)=NOx20 to 1000(0.01 to 0.05)1 to 50(0.5 to 25)NO220 to 1000(0.01 to 0.5)1 to 50(0.5 to 25)NOTE1Approximate range:25C and 101.3 kPa(1 atm).1.2 The test methods are based on the chemiluminescentreaction between nitric oxide and ozone.1.3 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.4 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.For specificprecautionary statements,see Section 9.2.Referenced Documents2.1 ASTM Standards:2D1356 Terminology Relating to Sampling and Analysis ofAtmospheresD1357 Practice for Planning the Sampling of the AmbientAtmosphereD1914 Practice for Conversion Units and Factors Relating toSampling and Analysis of AtmospheresD3195 Practice for Rotameter CalibrationD3249 Practice for General Ambient Air Analyzer Proce-duresD3609 Practice for Calibration Techniques Using Perme-ation TubesD3631 Test Methods for Measuring Surface AtmosphericPressure2.2 Other Documents:29 CFR,Part 1910,Occupational Safety and Health Stan-dards340 CFR,Parts 50 and 53,Environmental Protection AgencyRegulations on Ambient Air Monitoring Reference andEquivalent Methods33.Terminology3.1 Definitions:3.1.1 Four definitions of terms used in these test methodsrefer to Terminology D1356 and Practice D3249.4.Summary of Test Method4.1 The principle is based upon the chemiluminescence,orthe emission of light,resulting from the homogeneous gasphase reaction of nitric oxide and ozone(1).4The equation isas follows:NO1O35 NO2*1O2(1)NO2*5 NO21hvIn the presence of excess ozone,the intensity of the lightemission is directly proportional to the nitric oxide concentra-tion.4.2 To measure nitric oxide concentrations,the gas samplebeing analyzed is blended with ozone in a flow reactor.Theresulting light emissions are monitored by a photomultipliertube.1These test methods are under the jurisdiction of ASTM Committee D22 on AirQuality and are the direct responsibility of Subcommittee D22.03 on AmbientAtmospheres and Source Emissions.Current edition approved April 1,2012.Published May 2012.Originallyapproved in 1979.Last previous edition approved in 2005 as D3824-95(2005).DOI:10.1520/D3824-12.2For 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.3Available from Superintendent of Documents,U.S.Printing Office,Washington,DC 20402.4The boldface numbers in parentheses refer to the list of references at the end ofthese test methods.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 4.3 To measure total oxides of nitrogen(NOx=NO+NO2),the gas sample is diverted through a NO2to NO converterbefore being admitted to the flow reactor.4.4 To measure nitrogen dioxide(NO2),the gas sample isintermittently diverted through the converter,and the NOsignal subtracted from the NOxsignal.Some instrumentsutilize a dual stream principle with two reaction chambers.5.Significance and Use5.1 Most oxides of nitrogen are formed during high-temperature combustion.The Environmental ProtectionAgency(EPA)has set primary and secondary air qualitystandards for NO2that are designed to protect the public healthand the public welfare(40 CFR,Part 50).5.2 Oxides of nitrogen are generated by many industrialprocesses that can result in employee exposures.These areregulated by the Occupational Safety and Health Administra-tion(OSHA)which has promulgated exposure limits for theindustrial working environment(29 CFR,Part 1910).5.3 These methods have been found satisfactory for mea-suring oxides of nitrogen in the ambient and workplaceatmosphere over the ranges shown in 1.1.6.Interferences6.1 The chemiluminescent detection of NO with ozone isnot subject to interference from a