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ASTM E3260-21

(Guide)

Standard Guide for Forensic Examination and Comparison of Pressure Sensitive Tapes

Standard Guide for Forensic Examination and Comparison of Pressure Sensitive Tapes

SIGNIFICANCE AND USE
6.1 This guide is designed to assist the forensic tape examiner in selecting and organizing an analytical scheme for the analysis, comparison, and identification of tapes. The size and condition of the sample(s) influences the choice of analytical scheme. The evaluation and interpretation of the data for each technique is an important part of an analytical scheme but it is outside the scope of this guide. These will be addressed in other ASTM standards.
SCOPE
1.1 This guide is intended as an introduction to other standard guides for the forensic examination of pressure sensitive adhesive tape. It is intended to assist individuals who conduct forensic tape analyses in their evaluation, selection, and application of tests that can be of value to their examinations. This guide describes the construction and classification of various tapes and the methods to develop discriminatory information using an efficient order of testing. This standard provides an overview and guidance on the strengths and limitations of various techniques used in the analysis and comparison of pressure sensitive adhesive tapes. The goal is to provide a consistent approach to forensic tape analysis.  
1.2 The forensic tape examiner addresses concerns such as sample size, complexity and condition of the sample, environmental effects, collection and packaging methods, and case/investigation specific issues. These factors require that the forensic tape examiner choose test methods, sample preparation schemes, testing sequences, and degree of sample alteration and consumption that are suitable to each specific case.  
1.3 This standard is intended for use by competent forensic science practitioners with the requisite formal education, discipline-specific training (see Practice E2917, Practice E3233), and demonstrated proficiency to perform forensic casework.  
1.4 The values stated in SI units are to be regarded as standard. Other units of measurement are included in this standard as applicable to industrial usage.  
1.5 Some of the methods discussed in this guide involve the use of chemicals, temperatures, and radiation sources. 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.  
1.6 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.

General Information

Status
Published
Publication Date
31-Dec-2020
ICS
07.140 - Forensic science
Technical Committee
E30 - Forensic Sciences
Drafting Committee
E30.01 - Criminalistics
Current Stage
Ref Project

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ASTM E3260-21 - Standard Guide for Forensic Examination and Comparison of Pressure Sensitive TapesASTM E3260-21 - Standard Guide for Forensic Examination and Comparison of Pressure Sensitive Tapes
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ASTM E3260-21 - Standard Guide for Forensic Examination and Comparison of Pressure Sensitive Tapes
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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: E3260 − 21 An American National Standard
Standard Guide for
Forensic Examination and Comparison of Pressure
1
Sensitive Tapes
This standard is issued under the fixed designation E3260; 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 environmental practices and determine the applicability of
regulatory limitations prior to use.
1.1 This guide is intended as an introduction to other
1.6 This international standard was developed in accor-
standard guides for the forensic examination of pressure
dance with internationally recognized principles on standard-
sensitive adhesive tape. It is intended to assist individuals who
ization established in the Decision on Principles for the
conduct forensic tape analyses in their evaluation, selection,
Development of International Standards, Guides and Recom-
and application of tests that can be of value to their examina-
mendations issued by the World Trade Organization Technical
tions. This guide describes the construction and classification
Barriers to Trade (TBT) Committee.
of various tapes and the methods to develop discriminatory
information using an efficient order of testing. This standard
2. Referenced Documents
provides an overview and guidance on the strengths and
2
2.1 ASTM Standards:
limitations of various techniques used in the analysis and
D123 Terminology Relating to Textiles
comparison of pressure sensitive adhesive tapes. The goal is to
E1732 Terminology Relating to Forensic Science
provide a consistent approach to forensic tape analysis.
E2224 Guide for Forensic Analysis of Fibers by Infrared
1.2 The forensic tape examiner addresses concerns such as
Spectroscopy
sample size, complexity and condition of the sample, environ-
E2225 GuideforForensicExaminationofFabricsandCord-
mental effects, collection and packaging methods, and case/
age
investigation specific issues. These factors require that the
E2228 Guide for Microscopical Examination of Textile Fi-
forensic tape examiner choose test methods, sample prepara-
bers
tion schemes, testing sequences, and degree of sample altera-
E2917 Practice for Forensic Science Practitioner Training,
tion and consumption that are suitable to each specific case.
Continuing Education, and Professional Development
Programs
1.3 This standard is intended for use by competent forensic
E3085 Guide for Fourier Transform Infrared Spectroscopy
science practitioners with the requisite formal education,
in Forensic Tape Examinations
discipline-specific training (see Practice E2917, Practice
E3233 PracticeforForensicTapeAnalysisTrainingProgram
E3233), and demonstrated proficiency to perform forensic
2.2 Other Documents:
casework.
SWGMAT Guideline for Assessing Physical Characteristics
1.4 The values stated in SI units are to be regarded as
in Forensic Tape Examinations
standard. Other units of measurement are included in this
SWGMAT Guideline for Using Light Microscopy in Foren-
standard as applicable to industrial usage.
sic Tape Examinations
1.5 Some of the methods discussed in this guide involve the
SWGMAT Guideline for Using Scanning Electron
use of chemicals, temperatures, and radiation sources. This
Microscopy/Energy Dispersive X-Ray Spectroscopy in
standard does not purport to address all of the safety concerns,
Forensic Tape Examinations
if any, associated with its use. It is the responsibility of the user
SWGMAT Guideline for Using Pyrolysis-Gas Chromatog-
of this standard to establish appropriate safety, health, and
raphy and Pyrolysis-Gas Chromatography/Mass Spec-
trometry in Forensic Tape Examinations
1 2
This guide is under the jurisdiction of ASTM Committee E30 on Forensic For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Sciences and is the direct responsibility of Subcommittee E30.01 on Criminalistics. contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Current edition approved Jan. 1, 2021. Published January 2021. DOI: 10.1520/ Standards volume information, refer to the standard’s Document Summary page on
E3260-21. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
E3260 − 21
3. Terminology 3.2.15 machine direction, n—the direction of the tape that
runs the length of the tape.
3.1 Definitions:
3.2.16 migration, n—the movement over a period of time of
3.1
...

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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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1.1 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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SIGNIFICANCE AND USE
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SIGNIFICANCE AND USE
4.1 A training program provides the theoretical foundation and practical skills necessary for a trainee to become a qualified forensic hair examiner.  
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SCOPE
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.  
1.2 Forensic hair examiners are trained in accordance with Practice E2917 and the discipline-specific guidelines (Guide E3316) and criteria within this practice.  
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SIGNIFICANCE AND USE
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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4.3 Microscopical hair comparisons are not a means of individualization (10). This limitation is to be stated in any communication (for example, reports, testimony) when an association is reported.  
4.4 Additional analyses can be performed on hairs that have been chemically altered (for example, dyed hair) or have trace materials on the surface (for example, glitter). Such techniques are beyond the scope of this document.
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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.  
1.2 This guide addresses instrument setup, hair collection, sample handling techniques, and the use of various microscopes in the examination and comparison of hair.  
1.3 This guide addresses the benefit of following microscopical examinations with DNA analysis.  
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SIGNIFICANCE AND USE
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).  
5.2.1 Non-destructive XRD analysis can be performed in situ on geological material adhering to a substrate (see 8.12.3).  
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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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1.4 This standard is intended for use by competent forensic science practitioners with the requisite formal education, discipline-specific training (see Practice E2917), and demonstrated proficiency to perform forensic casework.  
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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
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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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4.3.1 Layer Elucidation—SEM images provide insight into the layer structure of a sample.  
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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.

  • Guide
    8 pages
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  • Guide
    8 pages
    English language
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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.

  • Guide
    6 pages
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