1、Designation:D476698(Reapproved 2014)Standard Test Method forVinyl Chloride in Workplace Atmospheres(Charcoal TubeMethod)1This standard is issued under the fixed designation D4766;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the ye
2、ar 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 describes the determination of vinylchloride monomer(VCM)in workplace atmospheres using amodified ch
3、arcoal tube method(see Practice D3686).1.2 This procedure is compatible with low flow rate per-sonal sampling equipment.It can be used for personal orstationary monitoring.It cannot determine instantaneous fluc-tuations in concentration to detect maximum values.Alterna-tive on-site procedures,such a
4、s gas chromatography or infraredspectrometry,must be used to measure fast-changing concen-trations.1.3 The range of this test method is from the limit ofdetection of approximately 0.01 to 100 ppm(v).1.4 The sampling method provides a time-weighted averagesample.1.5 The values stated in SI units are
5、to be regarded asstandard.The values given in parentheses are mathematicalconversions to inch-pound units that are provided for informa-tion only and are not considered standard.1.6 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibi
6、lity 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 more specificprecautionary statements,see Section 9 and Warnings in 10.2.3and 11.1.3.2.Referenced Documents2.1 ASTM Standards:2D1356 Ter
7、minology Relating to Sampling and Analysis ofAtmospheresD3686 Practice for Sampling Atmospheres to Collect Or-ganic Compound Vapors(Activated Charcoal Tube Ad-sorption Method)E355 Practice for Gas Chromatography Terms and Relation-ships3.Terminology3.1 DefinitionsFor definitions of terms relating to
8、 this testmethod,refer to Terminology D1356 and Practice E355.4.Summary of Test Method4.1 Known volumes of sample air are passed through glassor metal tubes packed with activated charcoal.Vinyl chloride isadsorbed on the charcoal and thus removed from the flowinggas stream(1-3).34.2 A two-section tu
9、be containing a front and a backupsection of adsorbent is used to collect the sample.4.3 The vinyl chloride is desorbed with carbon disulfide andanalyzed with a gas chromatograph equipped with a flameionization detector.Two or more different columns are to beused to reveal interferences that might o
10、therwise not bedetected.4.4 Adsorption/desorption efficiencies are determined bythe same techniques used for the atmospheric analysis appliedto known standards.Instrument calibrations are made withprepared standard solutions of vinyl chloride in carbon disul-fide.5.Significance and Use5.1 Vinyl chlo
11、ride monomer(VCM)is the starting materialfor the manufacture of poly(vinyl chloride)(PVC),which isused extensively in construction,electronics,packaging,andother industries.The vinyl chloride gas can escape duringmanufacturing,transportation,and polymerization stages.Re-sidual monomer can also escap
12、e during subsequent fabricationprocesses.5.2 Vinyl chloride is a toxic and explosive hazardousmaterial.1This test method is under the jurisdiction of ASTM Committee D22 on AirQuality and is the direct responsibility of Subcommittee D22.04 on Workplace AirQuality.Current edition approved Sept.1,2014.
13、Published September 2014.Originallyapproved in 1988.Last previous edition approved in 2009 as D4766 98(2009)1.DOI:10.1520/D4766-98R14.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume informat
14、ion,refer to the standards Document Summary page onthe ASTM website.3The boldface numbers in parentheses refer to the list of references at the end ofthis test method.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 5.3 Vinyl chloride is s
15、uspected to be a carcinogenic agent(4),and occupational exposure limits(OELs)have beenestablished for this agent.For instance,the present U.S.Occupational Safety and Health Administration(OSHA)stan-dard for VCM is 1.0 ppm(v)with a 0.5-ppm(v)action level;the maximum length of operator exposure at 5 p
16、pm(v)is 15min.45.4 The method is made selective for vinyl chloride bychoosing chromatograph columns that will separate vinylchloride from other organic compounds in the sample.5.5 The method meets requirements(for example,those ofOSHA)for monitoring workplace atmospheres in vinyl chlo-ride and poly(vinyl chloride)production and fabrication pro-cesses.6.Interferences6.1 Organic components that have the same or nearly thesameretentiontimeasvinylchlorideduringgas-chromatographic analysis will inter
