1、Designation:D720311Standard Practice forScreening Trichloroethylene(TCE)-Contaminated MediaUsing a Heated Diode Sensor1This standard is issued under the fixed designation D7203;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year
2、 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 practice describes procedures for screening mediaknown to contain the halogenated volatile organic compound(HVOC),
3、trichloroethylene(TCE).Procedure A is to be usedfor screening soil known to contain TCE and Procedure B is tobe used for screening water known to contain TCE.1.1.1 Both Procedures A and B involve measuring the TCEconcentration in the headspace above a sample using a heateddiode sensor device.From th
4、is measurement,an estimatedconcentration of TCE in the sample can be determined.AnyTCE remaining in the sample is not measured.Any otherHVOC present in the sample will be reported as TCE.1.2 Procedure A can also be used for screening the head-space above a soil suspected of containing HVOC contamina
5、-tion to indicate the presence or absence of HVOC contamina-tion in the soil.Procedure B can also be used for screening theheadspace above a water suspected of containing HVOCcontamination to indicate the presence or absence of HVOCcontamination in the water.For both procedures,any HVOCcontamination
6、 remaining in the soil or water is not detected bythis practice.1.3 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.3.1 ExceptionCertain inch-pound units are provided forinformation only.1.4 This standard does not purport to ad
7、dress 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-tion of regulatory limitations prior to use.NOTE1The diode sensor is heated to temperatures ranging betw
8、eenapproximately 600 and 1000 C(see 6.1.5)and as a result could be asource of ignition.2.Referenced Documents2.1 ASTM Standards:2D4547 Guide for Sampling Waste and Soils for VolatileOrganic CompoundsD5681 Terminology for Waste and Waste Management3.Terminology3.1 DefinitionsFor definitions of terms
9、used in this screen-ing practice,refer to Terminology D5681.4.Summary of Practice4.1 Procedure ATo estimate the concentration of TCE in asoil known to contain TCE contamination,a sample of the soilis added to a glass jar having an open-top cap with aPTFE-bonded silicone septum.At the time of screeni
10、ng,thetemperature of the soil in the jar should be approximately 50 to120 F(10 to 49 C).The soil in the jar is shaken and allowedto settle for 10 min,so the TCE can partition into the headspaceabove the soil.After 10 min,the TCE concentration in theheadspace is measured using a heated diode sensor d
11、evice,which gives a numerical voltage reading.The voltage readingfrom the device is converted to a mg/m3value of TCE in theheadspace in the container.Using this value,an estimatedconcentration of TCE in the soil in mg/Kg can be calculated.Any TCE remaining in the soil sample is not measured by thisp
12、ractice.Any other HVOC present in the soil will be reportedas TCE.4.1.1 To use Procedure A to screen a soil suspected ofcontaining HVOC contamination,a sample of the soil is addedto a glass jar having an open-top cap with a PTFE-bondedsilicone septum.At the time of screening,the temperature ofthe so
13、il in the jar should be approximately 50 to 120 F(10 to49 C).The soil in the jar is shaken and allowed to settle for 10min,so the HVOC can partition into the headspace above thesoil.After 10 min,the heated diode sensor device is used toscreen the headspace in the container.The numerical voltagereadi
14、ng from the device indicates the presence or absence of1This practice is under the jurisdiction of ASTM Committee D34 on WasteManagement and is the direct responsibility of Subcommittee D34.01.05 onScreening Methods.Current edition approved July 1,2011.Published August 2011.Originallyapproved in 200
15、5.Last previous edition approved in 2006 as D7203-061.DOI:10.1520/D7203-11.2For 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
16、 website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 HVOC contamination in the soil.Any HVOC contaminationremaining in the soil is not detected by this procedure.4.2 Procedure BTo estimate the concentration of TCE inwater known to contain TCE contamination,a sample of thewater is added to a glass jar having an open-top cap with aPTFE-bonded silicone septum.At the time of screening,thetemperature of the water in the jar should be a
