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TM_E_1412_
_12
Designation:E141212Standard Practice forSeparation of Ignitable Liquid Residues from Fire DebrisSamples by Passive Headspace Concentration WithActivated Charcoal1This standard is issued under the fixed designation E1412;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 practice describes the procedure for separation ofsmall quantities of ignitable liquid residues from samples offire debris using an adsorbent material to extract the residuefrom the static headspace above the sample,then eluting theadsorbent with a solvent.1.2 While this practice is suitable for successfully extractingignitable liquid residues over the entire range of concentration,the headspace concentration methods are best used when a highlevel of sensitivity is required due to a very low concentrationof ignitable liquid residues in the sample.1.2.1 Unlike other methods of separation and concentration,this practice is essentially nondestructive.1.3 Alternate separation and concentration procedures arelisted in the referenced documents(see Practices E1386,E1388,E1413,and E2154).1.4 This practice does not replace knowledge,skill,ability,experience,education,or training and should be used inconjunction with professional judgment.1.5 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.6 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:2E1386 Practice for Separation of Ignitable Liquid Residuesfrom Fire Debris Samples by Solvent ExtractionE1388 Practice for Sampling of Headspace Vapors from FireDebris SamplesE1413 Practice for Separation and Concentration of Ignit-able Liquid Residues from Fire Debris Samples by Dy-namic Headspace ConcentrationE1459 Guide for Physical Evidence Labeling and RelatedDocumentationE1492 Practice for Receiving,Documenting,Storing,andRetrieving Evidence in a Forensic Science LaboratoryE1618 Test Method for Ignitable Liquid Residues in Extractsfrom Fire Debris Samples by Gas Chromatography-MassSpectrometryE2154 Practice for Separation and Concentration of Ignit-able Liquid Residues from Fire Debris Samples by Pas-sive Headspace Concentration with Solid Phase Microex-traction(SPME)E2451 Practice for Preserving Ignitable Liquids and Ignit-able Liquid Residue Extracts from Fire Debris Samples3.Summary of Practice3.1 Charcoal in some form of an adsorption package isplaced in the sample container to adsorb ignitable liquidresidues.The container may be heated or left at ambienttemperature.The charcoal is removed and eluted with asuitable elution solvent as listed in 6.3.4.Significance and Use4.1 This practice is useful for preparing extracts from firedebris for later analysis by gas chromatography mass spec-trometry.4.2 This is a very sensitive separation procedure,capable ofisolating quantities smaller than110L of ignitable liquidresidue from a sample.5.Apparatus5.1 Heating SystemAn oven,or a heating mantle to fit theevidence container(or a hot plate).5.1.1 An oven is recommended to achieve a constanttemperature throughout the system.1This practice is under the jurisdiction of ASTM Committee E30 on ForensicSciences and is the direct responsibility of Subcommittee E30.01 on Criminalistics.Current edition approved June 1,2012.Published July 2012.Originally approvedin 1991.Last previous edition approved in 2007 as E1412 07.DOI:10.1520/E1412-12.2For 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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 5.2 Temperature Measuring DeviceA thermometer orthermocouple capable of measuring temperatures in the rangeof 40 to 150C.5.3 Adsorption Package.5.3.1 Commercial charcoal adsorption packages are avail-able from several companies.These packages,in the form ofpolymer strips or small charcoal canisters or“C bags,”are usedto adsorb organic vapors.5.3.1.1 The minimum recommended polymer strip size is 10mm by 10 mm,or 100 mm2.5.3.2 Non-Commercial Adsorption Packages.5.3.2.1 C-BagsPrepare C-bags by encapsulating 0.2 g ofactivated charcoal within a folded sheet of high strength,lightweight,high porosity tissue paper,such as that commonly usedfor making tea bags.35.3.3 StorageofAdsorptionPackagesTopreventcontamination,store all adsorption packages away from anysources of or