1、Designation: D5011 92 (Reapproved 2009)D5011 17Standard Practices forCalibration of Ozone Monitors Using Transfer Standards1This standard is issued under the fixed designation D5011; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision,
2、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 practices describe means for calibrating ambient, workplace or indoor ozone monitors, using transfer
3、 standards.1.2 These practices describe five types of transfer standards:(A) Analytical instrumentsPractice AAnalytical instruments,Practice BBoric acid potassium iodide (BAKI) manual analytical procedure,Practice CGas phase titration with excess nitric oxide,Practice DGas phase titration with exces
4、s ozone, andPractice EOzone generator device.(B) Boric acid potassium iodide (BAKI) manual analytical procedure(C) Gas phase titration with excess nitric oxide(D) Gas phase titration with excess ozone(E) Ozone generator device.1.3 These practices describe procedures to establish the authority of tra
5、nsfer standards: qualification, certification, and periodicrecertification.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with i
6、ts use. It is the responsibilityof the user of this standard to establish appropriate safety safety, health, and healthenvironmental practices and determine theapplicability of regulatory limitations prior to use. See Section 8 for specific precautionary statements.1.6 This international standard wa
7、s developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced
8、Documents2.1 ASTM Standards:2D1071 Test Methods for Volumetric Measurement of Gaseous Fuel SamplesD1193 Specification for Reagent WaterD1356 Terminology Relating to Sampling and Analysis of AtmospheresD3195 Practice for Rotameter CalibrationD3249 Practice for General Ambient Air Analyzer ProceduresD
9、3631 Test Methods for Measuring Surface Atmospheric PressureD3824 Test Methods for Continuous Measurement of Oxides of Nitrogen in the Ambient or Workplace Atmosphere by theChemiluminescent MethodD4230 Test Method of Measuring Humidity with Cooled-Surface Condensation (Dew-Point) HygrometerD5110 Pra
10、ctice for Calibration of Ozone Monitors and Certification of Ozone Transfer Standards Using Ultraviolet PhotometryE591 Practice for Safety and Health Requirements Relating to Occupational Exposure to Ozone (Withdrawn 1990)31 These practices are under the jurisdiction of ASTM Committee D22 on Air Qua
11、lity and are the direct responsibility of Subcommittee D22.03 on Ambient Atmospheresand Source Emissions.Current edition approved March 1, 2009Oct. 1, 2017. Published March 2009October 2017. Originally approved in 1989. Last previous edition approved in 20032009 asD5011 92 (2003).(2009). DOI: 10.152
12、0/D5011-92R09.10.1520/D5011-17.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 The last approved version of
13、 this historical standard is referenced on www.astm.org.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes
14、accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United
15、 States12.2 Other Documents:40 CFR Part 50 CFR Part 50, Environmental Protection Agency Regulations on Ambient Air Monitoring Reference Methods43. Terminology3.1 DefinitionsFor definitions of terms used in this standard, see Terminology D1356.3.2 Definitions of Terms Specific to This Standard:3.2.1
16、primary standardstandard, na standard directly defined and established by some authority, against which allsecondary standards are compared.3.2.2 secondary standardstandard, na standard used as a means of comparison, but checked against a primary standard.3.2.3 standardstandard, nan accepted referen
17、ce sample or device used for establishing measurement of a physical quantity.3.2.4 transfer standardstandard, na type of secondary standard. It is a transportable device or apparatus, which, togetherwith operational procedures, is capable of reproducing pollutant concentration or producing acceptabl
18、e assays of pollutantconcentrations.3.2.5 zero airair, npurified air that does not contain ozone and does not contain any other component that may interfere withthe measurement. See 7.1.3.3 Symbols:b = Spectrophotometer cell path length, cm. See Annex A2.davg = Average of discrete single point compa
19、risons. See Annex A1.di = Single point comparison. See Annex A1.FD = Diluent air flow, mL/min.FD = New diluent air flow, mL/min.FNO = NO flow, mL/min.FO = Flow through the O3 generator, mL/min.FR = Flowrate corrected to reference conditions (25C and 101.3 kPa), mL/min. See Annex A2.FS = Flowrate at
20、sampling conditions, mL/min. See Annex A2.FT = The total flow required at the output manifold (monitors demand plus 10 to 50 % excess), mL/min.I = The intensity of light which passes through the photometer absorption cell and is sensed by the detector when thecell contains an O3 sample. See Annex A4
21、.I2 i = Concentration of each I2 standard, mol I2/L. See Annex A2.Iavg = Average intercept. See Annex A1.Ii = Individual intercepts. See Annex A1.IO = The intensity of light which passes through the photometer absorption cell and is sensed by the detector when thecell contains zero air. See Annex A4
22、.mavg = Average slope. See Annex A1.mi = Individual slopes. See Annex A1.mol I2 = I2 released, mols. See Annex A2.NKIO3 = Normality of KIO3, equivalent/L. See Annex A2.NO = Diluted NO concentration, ppm. See Annex A4.NOORIG = Original NO concentration, ppm. See Annex A3.NOOUT = Highest NO concentrat
23、ion required at the output manifold, ppm. It is approximately equal to 90 % of the upper rangelimit of the O3 concentration to be determined. See Annex A3.NORC = NO concentration (approximate) in the reaction chamber, ppm. See Annex A3.NOREM = NO concentration remaining after addition of O3, ppm. Se
24、e Annex A3.NOSTD = Concentration of the undiluted NO standard, ppm.n = Number of comparisons. See Eq 4O3CERT = Certified O3 concentration, ppm.O3CERT = Diluted certified O3 concentration, ppm.O3GEN = O3 concentration produced by the O3 generator, ppm. See Annex A4.O3 OUT = Indicated O3 concentration
25、, ppm. See Annex A2.O3OUT = Diluted O3 concentration, ppm.O3 RC = O3 concentration (approximate) at the output manifold, ppm.PH2O = Vapor pressure of H2O at TS, kPa, wet volume standard. (For a dry standard, PH2O = 0.) (See Test Method D4230for tables of saturation vapor pressure of water.) See Anne
26、x A2.PR = Dynamic specification, determined empirically, to ensure complete reaction of O3 or NO, ppm/min.PS = Barometric pressure at sampling conditions, kPa. See Annex A2.4 Available from U.S. Government Printing Office, Superintendent of Documents, 732 N. Capitol St., NW, Mail Stop: SDE, Washingt
27、on, DC 20401,20401-0001,http:/www.access.gpo.gov.D5011 172Sc = Slope of KI calibration curve, mL/mol/cm. See Annex A2.sd = Standard deviation of single point comparisons. See Annex A1.si = Relative standard deviation of the six intercepts. See Annex A1.sm = Relative standard deviation of the six slo
28、pes. See Annex A1.tR = Residence time in reaction chamber, min.ts = Sampling time, min. See Annex A2.TS = Temperature at sampling conditions, C. See Annex A2URL = Upper range limit of O3 or NO monitor, ppm.Vi = Volume of I2 solution, mL. See Annex A2V O3 = Volume of O3 absorbed, L. See Annex A2.VR =
29、 Volume of air sampled, corrected to 25C and 101.3 kPa (1 atm), mL. See Annex A2.VR = Volume of air sampled, corrected to 25C and 101.3 kPa, mL. See Annex A2.VRC = Volume of the reaction chamber, mL.yi = O3 concentration indicated by the transfer standard, ppm. See 10.6.2.yi = O3 concentration indic
30、ated by the transfer standard, ppm. See 10.7.2.Z = Recorder response with zero air, % scale.4. Summary of Practices4.1 These practices describe the procedures necessary to establish the authority of ozone transfer standards: qualification,certification, and periodic recertification. Qualification co
31、nsists of demonstrating that a candidate transfer standard is sufficientlystable (repeatable) to be useful as a transfer standard. Repeatability is necessary over a range of variables (such as temperature,line voltage, barometric pressure, elapsed time, operator adjustments, relocation, etc.), any o
32、f which may be encountered duringuse of the transfer standard. Tests and possible compensation techniques for several such common variables are described. Detailedcertification procedures are provided, and the quantitative specifications necessary to maintain continuous certification of thetransfer
33、standard are also provided.4.2 MethodPractice AA dedicated ozone monitor is tested as described in 4.1 to demonstrate its authority as a transferstandard.4.3 MethodPractice BThis methodprocedure (1)5 is based on the reaction between ozone (O3) and potassium iodide (KI) torelease iodine (I2) in accor
34、dance with the following stoichiometric equation (2):O312I212H15I21H2O1O2 (1)The stoichiometry is such that the amount of I2 released is equal to the amount of O3 absorbed. Ozone is absorbed in a 0.1 Nboric acid solution containing 1 % KI, and the I2 released reacts with excess iodide ion (I) to for
35、m triiodide ion (I3), which ismeasured spectrophotometrically at a wavelength of 352 nm. The output of a stable O3 generator is assayed in this manner, andthe O3 generator is immediately used to calibrate the O3 monitor.4.4 MethodPractice CThis procedure is based on the rapid gas phase reaction betw
36、een nitric oxide (NO) and O3, as describedby the following equation (3):NO1O35NO1O2 (2)When O3 is added to excess NO in a dynamic system, the decrease in NO response is equivalent to the concentration of O3added. The NO is obtained from a standard NO cylinder, and the O3 is produced by a stable O3 g
37、enerator. A chemiluminescenceNO analyzer is used to measure the change in NO concentration. The concentration of O3 added may be varied to obtain calibrationconcentrations over the range desired. The dynamic system is designed to produce locally high concentrations of NO and O3 inthe reaction chambe
38、r, with subsequent dilution, to effect complete O3 reaction with relatively small chamber volumes.4.5 MethodPractice DThis procedure is based on the rapid gas phase reaction between O3 and nitric oxide (NO) as describedby the following equation (3):NO1O35NO21O2 (3)When NO is added to excess O3 in a
39、dynamic system, the decrease in O3 response observed on an uncalibrated O3 monitor isequivalent to the concentration of NO added. By measuring this decrease in response and the initial response, the O3 concentrationcan be determined. Additional O3 concentrations are generated by dilution. The gas ph
40、ase titration (GPT) system is used underpredetermined flow conditions to insure that the reaction of NO is complete and that further reaction of the resultant nitrogendioxide (NO2) with residual O3 is negligible.4.6 MethodPractice EA dedicated ozone generator is tested as described in 4.1 to demonst
41、rate its authority as a transferstandard.5 The boldface numbers in parentheses refer to the a list of references at the end of these practices.this standard.D5011 1735. Significance and Use5.1 The reactivity and instability of O3 precludes the storage of O3 concentration standards for any practical
42、length of time, andprecludes direct certification of O3 concentrations as SRMs. Moreover, there is no available SRM that can be readily and directlyadapted to the generation of O3 standards analogous to permeation devices and standard gas cylinders for sulfur dioxide andnitrogen oxides. Dynamic gene
43、ration of O3 concentrations is relatively easy with a source of ultraviolet (UV) radiation. However,accurately certifying an O3 concentration as a primary standard requires assay of the concentration by a comprehensively specifiedanalytical procedure, which must be performed every time a standard is
44、 needed.5.2 The primary UV standard photometers, which are usually used at a fixed location under controlled conditions, are used tocertify transfer standards that are then transported to the field sites where the ambient ozone monitors are being used. See PracticeD5110.5.3 The advantages of this pr
45、ocedure are:5.3.1 All O3 monitors in a given network or region may be traced to a single primary standard.5.3.2 The primary standard is used at only one location, under controlled conditions.5.3.3 Transfer standards are more rugged and more easily portable than primary standards.5.3.4 Transfer stand
46、ards may be used to intercompare various primary standards.6. Apparatus6.1 Apparatus Common to MethodsPractices A Through E:6.1.1 UV Photometric calibration system, as shown in Fig. 1, consisting of the following:6.1.1.1 Primary Ozone StandardStandard, a UV photometer, consisting of a low-pressure m
47、ercury discharge lamp,collimation optics (optional), an absorption cell, a detector, and signal-processing electronics. It shall be capable of measuring thetransmittance, I/I0, at a wavelength of 253.7 nm with sufficient precision that the standard deviation of the concentrationmeasurements does not
48、 exceed the greater of 0.005 ppm or 3 % of the concentration. It shall incorporate means to assure that noO3 is generated in the cell by the UV lamp. This is generally accomplished by filtering out the 184.9 nm Hg line with a high silicafilter. In addition, at least 99.5 % of the radiation sensed by
49、 the detector shall be 253.7 nm. This is usually accomplished by usinga solar blind photodiode tube. The length of the light path through the absorption cell shall be known with an accuracy within atleast 99.5 %. In addition the cell and associated plumbing shall be designed to minimize loss of O3 from contact with surfaces (4).See Practice D5110.6.1.1.2 Air Flow ControllerController, capable of regulating air flows as necessary to meet the output stability and photometerprecision requirements.6.1.1.3 FlowmetersFlowme
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