ASTM E1388-2017 Standard Practice for Static Headspace Sampling of Vapors from Fire Debris Samples《采用静态顶空法对燃烧残骸试样中的蒸气进行取样的标准实施规程》.pdf

《ASTM E1388-2017 Standard Practice for Static Headspace Sampling of Vapors from Fire Debris Samples《采用静态顶空法对燃烧残骸试样中的蒸气进行取样的标准实施规程》.pdf》由会员分享，可在线阅读，更多相关《ASTM E1388-2017 Standard Practice for Static Headspace Sampling of Vapors from Fire Debris Samples《采用静态顶空法对燃烧残骸试样中的蒸气进行取样的标准实施规程》.pdf（4页珍藏版）》请在麦多课文档分享上搜索。

1、Designation: E1388 12E1388 17Standard Practice forStatic Headspace Sampling of Headspace Vapors from FireDebris Samples1This standard is issued under the fixed designation E1388; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the

2、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 removing small quantities of ignitable liquid vapor from samples of

3、fire debris bysampling vapor from the headspace of the debris container.a fire debris container for the purpose of detecting or identifyingignitable liquid residues.1.2 Separation and concentration procedures are listed in the referenced documents. (See Practices E1386, E1412, E1413, andE2154.)1.3 T

4、his practice offers a set of instructions for performing one or more specific operations. This standard cannot replaceknowledge, skill, or ability acquired through appropriate education, training, and experience and should be used in conjunctionwith sound professional judgment.1.4 The values stated

5、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 its use. It is the responsibilityof the user of this standard to establish appropriate safety and

6、health practices and determine the applicability of regulatorylimitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Gu

7、ides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2E1386 Practice for Separation of Ignitable Liquid Residues from Fire Debris Samples by Solvent ExtractionE1412 Practice for Separation of Ignitable Li

8、quid Residues from Fire Debris Samples by Passive Headspace Concentration WithActivated CharcoalE1413 Practice for Separation of Ignitable Liquid Residues from Fire Debris Samples by Dynamic Headspace ConcentrationE1459 Guide for Physical Evidence Labeling and Related DocumentationE1492 Practice for

9、 Receiving, Documenting, Storing, and Retrieving Evidence in a Forensic Science LaboratoryE1618 Test Method for Ignitable Liquid Residues in Extracts from Fire Debris Samples by Gas Chromatography-MassSpectrometryE2154 Practice for Separation and Concentration of Ignitable Liquid Residues from Fire

10、Debris Samples by Passive HeadspaceConcentration with Solid Phase Microextraction (SPME)E2451 Practice for Preserving Ignitable Liquids and Ignitable Liquid Residue Extracts from Fire Debris Samples3. Summary of Practice3.1 The sample, headspace of an item is sampled, preferably in its original cont

11、ainer, is heated in order to volatilize any ignitableliquid residues present in the debris. After heating, the headspace is sampled and analyzed by gas chromatography-massspectrometry.for analysis by an appropriate technique (for example, gas chromatography-mass spectrometry). The container maybe he

12、ated prior to sampling to increase the volatility of any ignitable liquid residues.1 This practice in under the jurisdiction of ASTM Committee E30 on Forensic Sciences and is the direct responsibility of Subcommittee E30.01 on CriminalisticsCurrent edition approved Feb. 1, 2012July 15, 2017. Publish

13、ed March 2012July 2017. Originally approved in 1990. Last previous edition approved in 20052012 asE1388 05.E1388 12. DOI: 10.1520/E1388-12.10.1520/E1388-17.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM

14、 Standardsvolume information, refer to the standards Document Summary page on the ASTM website.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 pos

15、sible to adequately depict all changes 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, W

16、est Conshohocken, PA 19428-2959. United States14. Significance and Use4.1 This procedurepractice is particularly useful for screeningsampling fire debris samples to determine relative ignitable liquidconcentrations and possible ignitable liquid class to screen for the presence of ignitable liquid re

17、sidues prior to extraction withother techniques. It is most appropriate for sampling light to medium range ignitable liquids (such as light oxygenates, lacquerthinners, and other similar volatile compounds or products), and less appropriate for sampling ignitable liquids that havecompounds in the he

18、avy range.3, 4, 54.1.1 When sampled for screening purposes, the instrumentation typically utilized is a gas chromatograph with either a massspectrometer (GC-MS, refer to Test Method E1618) or flame ionization detector (GC-FID).4.2 This practice is useful when volatile oxygenated products such as alc

19、ohols or lacquer thinners aregenerally less efficient atrecovering limited quantities of ignitable liquids than Practices E1386suspected., E1412, E1413, and E2154, particularly for higherboiling compounds.4.3 This practice is the least sensitive of the sample preparation techniques and may not detec

20、t quantities of less than 10 L ofan ignitable liquid.4.3 Because this The separation takes place in a closed container, container and the sample remains in approximately the samecondition in which it was submitted. Repeat and interlaboratory analyses are therefore Since only a small aliquot of the s

21、ampleheadspace is removed for analysis, sample reanalysis may be possible.4.4 High concentrations of highly volatile compounds can saturate the headspace, inhibiting the recovery of less volatilecomponents and leading to the detection or identification of only the more volatile compounds in the samp

22、le.4.5 Due to variables in the debris This practice is intended for use in conjunction with other extraction techniques, such as thosedescribed in Practices E1386, E1412, E1413, and E2154sample condition prior to headspace sampling, complete reproducibilityof chromatograms may be difficult to obtain

23、., when analysis of a sample for all classes of ignitable liquids is required or desired.4.5.1 To obtain greater reproducibility, use one of the separation procedures which results in a solution of the ignitable liquidresidue (see Practices E1386, E1412, and E1413).NOTE 1The headspace specimen (the

24、portion in the syringe) is consumed in the analysis. Preserve an extract for potential reanalysis (see PracticeE2451) using an alternative separation and concentration practice, such as those described in Practices E1386, E1412, and E1413, if preservation isrequired per laboratory policies.4.5.2 To

25、obtain greater sensitivity for petroleum distillates and oxygenated products, use solid phase microextraction. (SeePractice E2154.)4.6 High concentrations of highly volatile compounds may swamp the headspace, inhibiting the recovery of less volatilecomponents.5. Apparatus5.1 Heating SystemAn oven, h

26、eating mantle or hot plate designed to fit the oven or equivalent, capable of reproducibletemperature operation for the desired range that can accommodate the evidence container.5.1.1 An oven is recommended to achieve a constant temperature throughout the system.5.2 Temperature Measuring DeviceA the

27、rmometer or thermocouple capable of measuring temperatures in the range from 40to 150C.required range of operation.5.3 Disposable or reusable gas-tight syringes, A gas-tight syringe capable of reproducibility introducing sample sizesreproducibly sampling in the range from 0.5 to 52.0 mL.5.4 Disposab

28、le 20 cc syringes.5.4 Disposable 1620 gauge syringe needles.Disposable or reusable syringe needles.5.5 Gas-tight vials and caps.5.6 A drill, punch, tool or other device to puncture holes in sample containers.device capable of creating holes in evidencecontainers (for example, drill, hole punch, hamm

29、er and nail).5.7 Tape, rubber sleeve stoppers, or equivalent, Headspace sample vials.capable of sealing holes in evidence containers.6. Sample Preparation6.1 Observe the appropriate procedures for handling and documentation of all submitted samples as described in Guide E1459and Practice E1492.3 Ett

30、ling, B. V., and Adams, M. F., “The Study of Accelerant Residues in Fire Remains,” Journal of Forensic Sciences, Vol 13, No. 1, 1968, pp. 7689.4 Stauffer, E., Dolan, J. A., and Newman, R., Fire Debris Analysis, Boston, MA: Academic Press, 2008.5 Hinshaw, J. V., “Headspace Sampling,” LCGC Europe, Vol

31、 24, No. 10, 2011.E1388 1726.1.1 Open and examine Examine the fire debris sample in order to determine that it is consistent with its description.descriptionprior to reporting. The examination may be performed prior to or after the sampling procedure in Section 7.6.1.1.1 Resolve any discrepancies be

32、tween the submitting agencys description of the evidence and the analysts observationprior to the completion of the report.6.2 Punch or drill a small hole in the container lid and cover the hole with tape.Prepare the sample or evidence container forheadspace sampling.6.2.1 Alternatively, a rubber sl

33、eeve stopper may be placed in the hole.Create a hole in the container lid such that a syringe needlecan be introduced. Seal the hole with tape, a rubber sleeve stopper, or as otherwise required. Alternatively, crack the container lidto allow a syringe needle to be introduced and close following samp

34、ling.NOTE 2Some cans designed for fire debris samples contain lids having rubber sleeve stoppers already in place.6.2.2 Some samples, such as liquids, may be transferred and sealed into vials for analysis without any further preparation.6.2.3 Prepare control samples and blanks for sampling using the

35、 same procedures used for questioned samples as required perlaboratory policies.6.3 If the sample is going to be heated, heating is required, place the container in the heating system until the container reachesthe desired temperature (not to exceed 90C).and remove immediately prior to sampling. Rec

36、ord the temperature and duration ofheating.6.3.1 Sampling at room temperature is appropriate to recover the more volatile compounds. Sampling at elevated temperatures,typically between 60C and 90C, is necessary to recover compounds with lower volatility.NOTE 3When other evidentiary considerations ar

37、ise (such as DNAor latent print examinations), consult with other relevant analyst(s) prior to heatingsamples.6.4 The syringe may be heated prior to sampling7. Sampling Procedure7.1 Direct Headspace Sampling:Headspace Sampling for Manual Injection:7.1.1 Assemble a syringe and needle (sampling syring

38、e) as needed. The syringe should be heated to the sampling temperatureprior to sampling.7.1.2 Remove the container from the heating apparatus then push the syringe through the tape or rubber sleeve stopper into thehole in the container lid. Slowly pump the syringe several times, withdraw from the li

39、d, and inject Withdraw between 0.5 to 2.0mL of sample into the gas chromatograph. Analyze as described in Test Method headspace from the evidence container into asampling syringe.E1618.7.1.2.1 Sample from an area above the fire debris in the evidence container.7.1.3 Immediately analyze the specimen

40、using an appropriate instrumental technique (for example, gas chromatography-massspectrometry).7.1.4 After sampling, reseal the evidence container as needed or prepare as necessary for any additional analyses to includeother fire debris extraction techniques.7.1.5 After the headspace sample has been

41、 removed, reseal the hole.Perform sampling on control samples and blanks followingthe same procedures used for questioned samples as required in accordance with laboratory policies.7.2 Indirect Headspace Sampling Using Headspace Sample Vials:Headspace Sampling for Automated Injection System:7.2.1 So

42、me automated sample injection systems utilize headspace sample vials for delivery of thea sample headspace into thegas chromatograph.7.2.2 Assemble and seal (crimp (for example, crimp or screw) lidcap onto headspace sample vial. Using a 20 cc syringe andneedle, puncture the headspace vial septum and

43、 evacuate the contents of the vial. Repeat this procedure 3 to 4 times.vial.7.2.3 Assemble a syringe and needle (sampling syringe) as needed to be used for evacuating the sealed headspace vial andremoving headspace samples from an evidence container.7.2.3.1 Syringe size (volume capacity) may vary bu

44、t the sampling syringe should have approximately the same or greatervolume capacity as the vials.7.2.4 Evacuate a portion of the sealed vial using the sampling syringe. Repeat this procedure until the equivalent of at least twicethe volume capacity of the vial has been evacuated.NOTE 4A needle assem

45、bly attached directly to a vacuum source may be used to evacuate the vial as an alternative to using a sampling syringe.7.2.5 Withdraw a sample of the headspace above the fire debris from the evidence container using a sampling syringe.7.2.6 Remove the container from the heating apparatus then push

46、the 20 cc syringe through the tape or rubber sleeve stopperinto the hole in the container lid. Slowly pump the syringe several times, withdraw 20 cc of vapor and inject into headspace samplevial. Repeat this process 2 to 4 times.Immediately transfer the contents of the sampling syringe into the evac

47、uated vial. Repeat thisprocess until the injected volume of headspace from the evidence container approximates the volume previously evacuated fromthe vial.E1388 1737.2.3.1 If the headspace sample vial was properly sealed and evacuated, the vacuum created should pull the initial injection intothe vi

48、al. The latter injections into the vial will require forcibly injecting the 20 cc sample.NOTE 5If the vial was properly sealed and evacuated, the vacuum created should pull the contents of the sampling syringe of the initial headspacesample into the vial. Any subsequent sampling and transfer could r

49、equire some effort to push the contents of the sampling syringe into the vial.7.2.3.2 The sequence method on the gas chromatograph should be setup to inject 0.5 to 2.0 mL of the sample into the gaschromatograph. Analyze as described in Test Method E1618.7.2.7 Immediately analyze specimens, using an appropriate instrumental technique (for example, gas chromatography-massspectrometry).7.2.8 After the headspace samples have been removed, reseal the hole in the container.sampling, reseal the container as neededor prepare as necessary for any additional analyses to