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ASTM E3085-17

(Guide)

Standard Guide for Fourier Transform Infrared Spectroscopy in Forensic Tape Examinations

Standard Guide for Fourier Transform Infrared Spectroscopy in Forensic Tape Examinations

SIGNIFICANCE AND USE
5.1 This guide is designed to assist an examiner in the selection of appropriate sample preparation methods for the analysis, comparison, and identification of pressure sensitive adhesive (PSA) tapes. If no meaningful differences are noted between the known and unknown samples regarding physical appearance or measurements, then IR spectroscopy should be the next step in the analytical scheme.  
5.2 Infrared spectroscopy can provide molecular information regarding major organic and inorganic components. For various reasons, components in lesser amounts are typically more difficult to identify unequivocally. Reasons for this include interference of the absorption bands of the major components with the less intense bands of minor components and sensitivity issues whereby the minor components are present at concentrations below the detection limits of the instrument.  
5.3 Infrared spectroscopy can be used to obtain spectra for elucidation of the chemical composition of a tape and for comparison of two or more tape samples. When used for spectral comparisons, the objective is to determine whether any meaningful differences exist between the samples.
SCOPE
1.1 Infrared spectroscopy (IR) is a valuable method for the identification and comparison of pressure sensitive tapes (1-20).2 This guide provides basic recommendations and information about infrared spectrometers and accessories, with an emphasis on sampling techniques specific to pressure sensitive tape examinations. The particular method(s) employed by each examiner or laboratory will depend upon available equipment, examiner training, sample suitability, and sample size.  
1.2 This guide is intended for examiners with a basic knowledge of the theory and proficiency in the use of infrared spectroscopy as well as experience in the handling and forensic examination of pressure sensitive tapes. Further, this guide is to be used in conjunction with a broader analytical scheme (21-23).  
1.3 Disclaimer: This guide offers a set of instructions for performing one or more specific operations. This standard cannot replace knowledge, skill, or the ability acquired through appropriate education, training, and experience and should be used in conjunction with sound professional judgment.  
1.4 The values stated 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 responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

Status
Published
Publication Date
28-Feb-2017
ICS
07.140 - Forensic science
Technical Committee
E30 - Forensic Sciences
Drafting Committee
E30.01 - Criminalistics
Current Stage
Ref Project

Relations

Refers
ASTM E2224-18 - Standard Guide for Forensic Analysis of Fibers by Infrared Spectroscopy
Effective Date
01-Sep-2018

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ASTM E3085-17 - Standard Guide for Fourier Transform Infrared Spectroscopy in Forensic Tape ExaminationsASTM E3085-17 - Standard Guide for Fourier Transform Infrared Spectroscopy in Forensic Tape Examinations
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ASTM E3085-17 - Standard Guide for Fourier Transform Infrared Spectroscopy in Forensic Tape Examinations
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This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: E3085 − 17 An American National Standard
Standard Guide for
Fourier Transform Infrared Spectroscopy in Forensic Tape
1
Examinations
This standard is issued under the fixed designation E3085; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope E573 Practices for Internal Reflection Spectroscopy
E1421 Practice for Describing and Measuring Performance
1.1 Infrared spectroscopy (IR) is a valuable method for the
of Fourier Transform Mid-Infrared (FT-MIR) Spectrom-
identification and comparison of pressure sensitive tapes (1-
2 eters: Level Zero and Level One Tests
20). This guide provides basic recommendations and infor-
E1492 Practice for Receiving, Documenting, Storing, and
mation about infrared spectrometers and accessories, with an
Retrieving Evidence in a Forensic Science Laboratory
emphasis on sampling techniques specific to pressure sensitive
E2224 Guide for Forensic Analysis of Fibers by Infrared
tape examinations.The particular method(s) employed by each
Spectroscopy
examiner or laboratory will depend upon available equipment,
examiner training, sample suitability, and sample size.
3. Terminology
1.2 This guide is intended for examiners with a basic
3.1 Definitions—For terms relevant to molecular
knowledge of the theory and proficiency in the use of infrared
spectroscopy, refer to Terminology E131.
spectroscopyaswellasexperienceinthehandlingandforensic
3.1.1 background, n—the signal produced by the entire
examinationofpressuresensitivetapes.Further,thisguideisto
analytical system apart from the material of interest.
be used in conjunction with a broader analytical scheme
(21-23).
3.1.2 elastomer, n—the polymeric backbone of a pressure
sensitive adhesive imparting elastic properties, for example,
1.3 Disclaimer: This guide offers a set of instructions for
rubber.
performing one or more specific operations. This standard
cannotreplaceknowledge,skill,ortheabilityacquiredthrough
3.1.3 fiber reinforcement, n—the fabric portion of some
appropriate education, training, and experience and should be
pressure sensitive adhesive tapes; also referred to as scrim.
used in conjunction with sound professional judgment.
3.1.4 filler/extender, n—an inorganic material that is added
1.4 The values stated in SI units are to be regarded as
to a tape to modify a physical property or reduce cost.
standard. No other units of measurement are included in this
3.1.5 low e-glass, n—adichroicmirrorthatiscoatedwithan
standard.
IR reflective surface.
1.5 This standard does not purport to address all of the
3.1.5.1 Discussion—Such glass is suitable for use as a
safety concerns, if any, associated with its use. It is the
sample support when performing IR reflection techniques.
responsibility of the user of this standard to establish appro-
3.1.6 meaningful difference, n—a feature or property of a
priate safety and health practices and determine the applica-
sample that does not fall within the variation exhibited by the
bility of regulatory limitations prior to use.
comparison sample, considering the limitations of the sample
or technique, and therefore indicates the two samples do not
2. Referenced Documents
share a common origin.
3
2.1 ASTM Standards:
3.1.6.1 Discussion—The use of this term does not imply the
E131 Terminology Relating to Molecular Spectroscopy
formal application of statistics.
3.1.7 pressure-sensitive adhesive, n—a viscoelastic material
1
This guide is under the jurisdiction of ASTM Committee E30 on Forensic
which, in solvent-free form, remains tacky and will adhere
Sciences and is the direct responsibility of Subcommittee E30.01 on Criminalistics.
Current edition approved March 1, 2017. Published March 2017. DOI: 10.1520/
instantaneously to most solid surfaces with the application of
E3085-17.
very slight pressure.
2
The boldface numbers in parentheses refer to a list of references at the end of
this standard.
3.1.8 pressure-sensitive adhesive (PSA) tape, n—a combi-
3
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
nation of a pressure sensitive adhesive with a continuous
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
flexiblebacking(forexample,cloth,paper,metal,orplastic)or
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. with a backing and release liner.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 194
...

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SIGNIFICANCE AND USE
4.1 µ-XRF is a nondestructive qualitative elemental analysis technique used for polymers. It involves excitation of a sample by an X-ray source resulting in the emission of characteristic X-rays detected using an energy dispersive X-ray detector. Results are displayed simultaneously as a spectrum of intensity as a function of energy for elements of atomic number 11 or greater.  
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1.4 This guide is intended to be applied within the scope of a broader analytical scheme (for example, Guide E1610, Guide E3260) for the forensic analysis of a polymer sample (1-6).2 A µ-XRF analysis can provide additional information regarding the potential relationships between the sources of polymeric materials.  
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5.1 This guide is designed to assist an examiner in the selection of appropriate sample preparation methods for the analysis, comparison, and identification of fibers using IR spectroscopy. IR spectroscopy can provide additional compositional information than is obtained using polarized light microscopy alone. The extent to which IR spectral comparison is conducted will vary with specific sample and case evaluations.  
5.2 IR analysis should follow visible and fluorescence comparison microscopy, polarized light microscopy, and ultraviolet (UV)/visible spectroscopy. If no meaningful differences are noted between the known and unknown samples in optical properties, then proceed to IR spectroscopy as the next step in the analytical scheme, as applicable.  
Note 1: IR analysis generally follows the aforementioned techniques since sample preparation (for example, flattening) irreversibly changes fiber morphology.  
5.3 IR spectroscopy should be conducted before dye extraction for chromatography due to the semi-destructive nature of the extraction technique. Because of the large number of sub-generic classes, forensic examination of acrylic and modacrylic fibers is likely to benefit significantly from IR spectral analysis (5). Useful distinctions between subtypes of nylon and polyester fibers can also be made by IR spectroscopy.  
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1.1 Infrared (IR) spectroscopy is a valuable method of fiber polymer identification and comparison in forensic examinations. The use of IR microscopes, coupled with Fourier transform infrared (FTIR) spectrometers, has greatly simplified the IR analysis of single fibers, thus making the technique feasible for routine use in the forensic laboratory. This guide provides basic recommendations and information about IR spectrometers and accessories, with an emphasis on sampling techniques specific to fiber examinations. The particular method(s) employed by each examiner or laboratory will depend upon available equipment, examiner training, sample suitability, and sample size.  
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SIGNIFICANCE AND USE
5.1 TLC is an inexpensive and simple technique that could be used to complement other analytical techniques within a general analytical scheme related to forensic fiber examination.  
5.2 Consider the forensic analysis of fiber colorants using TLC for single fiber comparisons only when the sample size is adequate (that is, enough colorant can be extracted for analysis) and it is not possible to discriminate between the fibers of interest using other techniques, such as comparison microscopy and MSP. Larger fibrous units (for example, thread or tuft) can be treated as an individual sample if determined to be homogeneous. Do not treat fibers that cannot be directly related to each other as a collective sample for the purposes of TLC.  
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1.1 This guide is intended as an overview of the Thin-Layer Chromatography (TLC) of fiber colorants (or individual dye components) present in dyed fibers. It is intended to be applied within the scope of a broader analytical scheme for the forensic analysis of fiber samples. TLC could provide information that cannot be obtained through other color analyses (such as microspectrophotometry (MSP)) (1).2  
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1.1 This practice covers training guidelines for use by forensic laboratory personnel responsible for training forensic examiners that will perform hair examinations, including microscopical comparisons of human hair.  
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4.1 A microscopical hair examination is conducted to determine if the item is a hair; from a human; from a particular somatic region; characteristic of a broad geographically-assigned ancestral group; characteristic of a particular growth phase; damaged; symptomatic of disease, condition, or disorder; forcibly removed; chemically altered (for example, dyed or bleached); suitable for microscopical comparison; suitable for DNA analysis; and similar to or different from a known sample (4-9).  
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1.1 This guide covers procedures used by forensic laboratory personnel in the forensic examination of hair by microscopy, including microscopical comparisons and classification of hair samples.  
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5.1 The overarching goals of the forensic analysis of geological materials include (A) identification of an unknown material (see 11.3), (B) analysis of soils, sediments, or rocks to restrict their possible geographic origins as part of a provenance analysis (see 11.4), and (C) comparison of two or more samples to assess if they could have originated from the same source or to exclude a common source based on observation of exclusionary differences (see 11.5). XRD is only one analytical method that can be applied to the evidentiary samples in service of these distinct goals.  
5.2 Within the analytical scheme of geological materials, XRD analysis is used to: identify the crystalline components within a sample; identify the crystalline components separated from a mixture, typically clay-sized material (see 8.8), or a selected particle class for which additional analysis is needed (see 8.11); or compare two or more samples based on the identified crystalline phases or diffraction patterns (see 11.5).  
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1.1 This guide covers techniques and procedures for the use of powder X-ray diffraction (XRD) in the forensic analysis of geological materials (to include soils, rocks, sediments, and materials derived from them such as concrete), to enable non-consumptive identification of solid crystalline materials present as single components or multi-component mixtures.  
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4.1 This guide is intended to advise and assist the analyst in the preparation of polymer samples (for example, paint and tape) for SEM/EDS, the collection of data by SEM/EDS, and the interpretation of images and data resulting from these analyses.  
4.2 When polymers are constructed as layered materials, SEM/EDS analysis is conducted on each polymeric layer individually. This analysis can be hindered by a non-discernable layer structure (for example, smear, irregular segregation within the layer system).  
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4.3.4 Relative Elemental Abundance Determination—An EDS spectrum permits the relative abundance of elements in samples to be compared.  
4.4 In the context of a forensic polymer comparison, the evaluation of SEM/EDS results are intended to provide insight into the following forensic tasks:  
4.4.1 Comparison of structure, texture, and elemental data.  
4.4.2 Support for results from other instruments (for example, the presence of calcium, oxygen, and carbon in the EDS spectrum obtained from discrete particles indicates the presence of calcium carbonate as observed in an infrared spectrum). Refer to Guides E2937 and E3085 for further details.  
4.4.3 Significance of results given the presence of certain elements, layer structures, or textures.
SCOPE
1.1 This guide covers recommended techniques and procedures intended for use by forensic laboratory personnel that perform SEM/EDS analyses on polymer samples.  
1.2 This guide describes various techniques and procedures used in the SEM/EDS analysis of polymers that include sample handling and preparation, instrument operating conditions, and spectral data collection, evaluation and interpretation.  
1.3 The theoretical aspects of many of the topics presented can be found in texts such as Scanning Electron Microscopy and X-ray Microanalysis (1).2  
1.4 This guide is intended to be applied within the scope of a broader analytical scheme (for example, Guides E1610, E3260) for the forensic analysis of a polymer sample. An SEM/EDS analysis can provide additional information regarding the potential relationships between the sources of polymeric materials.  
1.5 This guide is intended for use by competent forensic science practitioners with the requisite formal education, discipline-specific training (see Practices E2917, E3233, and E3234), and demonstrated proficiency to perform forensic casework.  
1.6 The values stated in SI units are to be regarded as standard. Other units of measurement are included in this standard where applicable as a result of common usage (for example, keV).  
1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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  • Guide
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ASTM
ASTM E3296-22(Guide)
Standard Guide for Using Pyrolysis Gas Chromatography and Pyrolysis Gas Chromatography-Mass Spectrometry in Forensic Polymer Examinations

SIGNIFICANCE AND USE
4.1 This guide provides guidance in the selection of appropriate sample preparation methods and instrumental parameters for the analysis, comparison, or identification of various polymeric materials by PGC and PGC/MS.  
4.1.1 PGC/MS can differentiate between classes of fibers (for example, acrylic, polyester, nylon) and within classes of fibers (for example, acrylics) (1-3).5  
4.1.2 Paint binders are differentiated based upon the variety of monomers used in paint formulations which could be difficult to identify by other analytical techniques. In addition, some additives can be detected or identified.  
4.1.3 Differentiation can be achieved by the separation and identification of organic components in the adhesive portion of tapes (4, 5) and in the backings of electrical tapes (6).  
4.1.4 PGC/MS can provide additional discrimination for other types of polymers such as automotive lenses, automotive body fillers, cosmetics, plastics, and rubbers (7-9).  
4.2 Pyrolysis breaks a large molecule into many smaller molecules in a reproducible fashion through the breaking of bonds by means of the application of thermal energy. Analytical pyrolysis is used to provide chemical information on organic-containing solids that cannot be dissolved or otherwise introduced into a chromatographic system. It is also used to analyze and compare solvents bound in a solid material (such as tape adhesives) (10). When analyzed using a separation technique such as gas chromatography, the smaller molecules produced through the action of pyrolysis form a pattern of separated fragments. Mass and structural information indicative of the original molecule are also available when a mass spectral detector is used.  
4.3 Although a destructive method, and therefore often placed at the end of an analytical scheme, the pyrograms produced from different polymer compositions form characteristic patterns that are useful for both identification of polymer type and comparisons between samples (4, 6...
SCOPE
1.1 This guide covers information and recommendations for the selection and application of various PGC and PGC/MS procedures and methods in the forensic examination of polymeric materials (for example, fibers, paint, tape). PGC and PGC/MS methods are used for the identification and comparison of the organic components of these materials. Refer to Practice D3452 for further information on the preparation of the pyrolysis system for polymeric analyses.  
1.2 This guide is to be used in conjunction with a broader analytical scheme such as Guides E1610 or E3260, or the SWGMAT Forensic Fiber Examination Guidelines.  
1.3 This standard is intended for use by competent forensic science practitioners with the requisite formal education, discipline-specific training (see Practices E2917, E3233, E3234), and demonstrated proficiency to perform forensic casework.  
1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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