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TM_E_1413_
_13
Designation:E141313Standard Practice forSeparation of Ignitable Liquid Residues from Fire DebrisSamples by Dynamic Headspace Concentration1This standard is issued under the fixed designation E1413;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 fire debrissamples using the method of dynamic headspace concentra-tion.1.2 Dynamic headspace concentration uses adsorption andsubsequent solvent elution or thermal desorption.1.3 Both positive and negative pressure systems for adsorp-tion are described,as well as a thermal desorption system.1.4 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.1.5 Alternate separation and concentration procedures arelisted in Section 2.If archival of the extract is of importance,then this practices thermal desorption procedure,SPME(Prac-tice E2154),and headspace(Practice E1388)sample separationtechniques are not recommended unless a portion of the extractcan be split and retained.In order to have an archivable extract,then this practices sample collection on charcoal,solventextraction(Practice E1386),or passive headspace concentra-tion(Practice E1412)is recommended.1.6 This practice offers a set of instructions for performingone or more specific operations.This standard cannot replaceknowledge,skill,or ability acquired through appropriateeducation,training,and experience and should be used inconjunction with sound professional judgment.1.7 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 SamplesE1412 Practice for Separation of Ignitable Liquid Residuesfrom Fire Debris Samples by Passive Headspace Concen-tration With Activated CharcoalE1459 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 The sample,preferably in its original container,isheated,forcing volatile compounds to vaporize.The headspacein the sample is then drawn or pushed through a tubecontaining an adsorption media(typically activated charcoal orTenax)which adsorbs the vaporized compounds.3.2 Other solid adsorbents and collection systems can beused as long as the method has been validated with a widevariety of ignitable liquids with a range of both flash points andpolarity.4.Significance and Use4.1 This practice is useful for preparing extracts from firedebris for later analysis by gas chromatography-mass spec-trometry(GC-MS),see Test Method E1618.1This 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 Aug.15,2013.Published September 2013.Originallyapproved in 1991.Last previous edition approved in 2007 as E1413 07.DOI:10.1520/E1413-13.2For 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 4.2 This is a very sensitive separation procedure,capable ofisolating quantities smaller than 0.1 L of ignitable liquidresidue from a sample4.2.1 Actual recovery will vary,depending on severalfactors,including adsorption temperature,container size,andcompetition from the sample matrix.4.3 This is a potentially destructive technique.Portions ofthe sample subjected to this procedure may not be suitable forre-sampling.Therefore,a portion of the sample extract shouldbe