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ASTM E3316-22

(Guide)

Standard Guide for Forensic Examination of Hair by Microscopy

Standard Guide for Forensic Examination of Hair by Microscopy

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).  
4.2 Most often, hairs from the head and pubic regions of the body are used for microscopical comparisons. There is usually more interpersonal variability in the characteristics of head and pubic hairs than in the hairs from other somatic regions. Head hairs usually show more interpersonal variation than pubic hairs. Hairs from other somatic regions may also be compared, but these comparisons are usually limited and less frequently conducted. Accordingly, this guide primarily considers human head and pubic hair comparisons.  
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.
SCOPE
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.  
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.  
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
30-Apr-2022
ICS
07.140 - Forensic science
Technical Committee
E30 - Forensic Sciences
Drafting Committee
E30.01 - Criminalistics
Current Stage
Ref Project

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ASTM E3316-22 - Standard Guide for Forensic Examination of Hair by MicroscopyASTM E3316-22 - Standard Guide for Forensic Examination of Hair by Microscopy
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ASTM E3316-22 - Standard Guide for Forensic Examination of Hair by Microscopy
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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: E3316 − 22 An American National Standard
Standard Guide for
1
Forensic Examination of Hair by Microscopy
This standard is issued under the fixed designation E3316; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope E1732Terminology Relating to Forensic Science
E2917Practice for Forensic Science Practitioner Training,
1.1 This guide covers procedures used by forensic labora-
Continuing Education, and Professional Development
tory personnel in the forensic examination of hair by
Programs
microscopy, including microscopical comparisons and classi-
fication of hair samples. 2.2 Other Standards:
3
ISO 17025Testing and calibration laboratories
1.2 This guide addresses instrument setup, hair collection,
sample handling techniques, and the use of various micro-
3. Terminology
scopes in the examination and comparison of hair.
3.1 Definitions—For definitions of terms used in this guide,
1.3 This guide addresses the benefit of following micro-
refer to Terminology E1732.
scopical examinations with DNA analysis.
3.2 Definitions of Terms Specific to This Standard:
1.4 This standard is intended for use by competent forensic
3.2.1 anagen,n—theactivegrowthphaseofahairfolliclein
science practitioners with the requisite formal education,
the hair growth cycle.
discipline-specific training (see Practice E2917), and demon-
strated proficiency to perform forensic casework. 3.2.1.1 Discussion—The root from a pulled anagen hair is
4
elongated and is usually fully pigmented (1).
1.5 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
3.2.2 ancestral group, n—a biogeographic designation of
responsibility of the user of this standard to establish appro-
human populations (for example, Asian, African, European)
priate safety, health, and environmental practices and deter-
whose hair can share similar morphological and microscopic
mine the applicability of regulatory limitations prior to use.
traits.
1.6 This international standard was developed in accor-
3.2.2.1 Discussion—The racial terms Caucasoid,
dance with internationally recognized principles on standard-
Mongoloid, and Negroid should not be used as these terms are
ization established in the Decision on Principles for the
nolongeracceptableinthefieldofanthropology(thefieldfrom
Development of International Standards, Guides and Recom-
which these designations originated) (2).
mendations issued by the World Trade Organization Technical
3.2.3 association, inclusion, n—the result of a comparison
Barriers to Trade (TBT) Committee.
between two hair samples in which the characteristics of the
questioned hair are present in the known sample without any
2. Referenced Documents
exclusionarydifferences,andthereforethedonoroftheknown
2
2.1 ASTM Standards:
hair sample can be included as a possible source of the
E620Practice for Reporting Opinions of Scientific or Tech-
questioned hair.
nical Experts
3.2.3.1 Discussion—A microscopical association of hair
E1459Guide for Physical Evidence Labeling and Related
cannot identify the definitive source of a questioned hair to the
Documentation
exclusion of all others, and the number of individuals who
E1492Practice for Receiving, Documenting, Storing, and
could be included as a possible donor of a specific hair is
Retrieving Evidence in a Forensic Science Laboratory
unknown and cannot be reliably estimated.
3.2.4 buckling, n—an abrupt change in the shape and
orientation of a hair shaft with or without a slight twist.
1
ThistestmethodisunderthejurisdictionofASTMCommitteeE30onForensic
Sciences and is the direct responsibility of Subcommittee E30.01 on Criminalistics.
Current edition approved May 1, 2022. Published October 2022. DOI: 10.1520/
E3316-22.
2 3
For referenced ASTM standards, visit the ASTM website, www.astm.org, or Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM 4th Floor, New York, NY 10036, http://www.ansi.org.
4
Standards volume information, refer to the standard’s Document Summary page on Theboldfacenumbersinparenthesesrefertothelistofreferencesattheendof
the ASTM website. this standard.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
E3316 − 22
3.2.5 catagen, n—the transitional phase
...

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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 covers recommended techniques and procedures intended for use by forensic laboratory personnel that perform µ-XRF analysis of polymer samples.  
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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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4.1 Color is an easily observable characteristic of soils and is integral to the taxonomic classifications of soils (6-8); factors including parent material, hydrology, vegetation, and extent of soil weathering, can affect soil color, making color a valuable diagnostic tool for forensic examination purposes.  
4.2 Soil color is sufficiently variable among soils to be used for differentiation of many soils in forensic examinations (9, 10) (see Section 6 for the test method for color determination and comparison criteria) as determined by visual characterization in the Munsell color system.  
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SCOPE
1.1 This practice covers visual color determination of soil/geologic material within the context of a forensic examination and is intended for use by laboratory personnel.  
1.1.1 This practice recommends use of soil color for: the initial screening of soil samples in forensic casework, prioritization of known soil exemplars for detailed analysis, and includes a test method for color determination in the Munsell color system and comparison among samples.  
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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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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.  
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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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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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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).  
5.2.2 The most common forensic applications of XRD to geological materials are (A) identification or confirmation of a selected phase or fraction of a sample (see 8.12), (B) identification of minerals in the clay-sized fractions of soils (see 8.8), and (C) identification of the phases of the hydrated cement component of concrete or mortar.  
5.3 This guide is intended to be used with other methods of analysis (for example, polarized light microscopy, scanning electron microscopy, palynology) within a more comprehensive analytical scheme for the forensic analysis or comparison of geological materials.  
5.3.1 Comprehensive criteria for forensic comparisons of geological material integrating multiple analytical methods and provenance estimations (see 11.4) are not included and are beyond the scope of this guide.
SCOPE
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.  
1.2 This guide makes recommendations for the preparation of geological materials for powder XRD analysis with adaptations for samples of limited quantity, instrumental configuration to generate high-quality XRD data, identification of crystalline materials by comparison to published diffraction data, and forensic comparison of XRD patterns from two or more samples of geological materials to support criminal investigations.  
1.3 Units—The values stated in SI units are to be regarded as standard. Other units are avoided, in general, but there is a long-standing tradition of expressing X-ray wavelengths and lattice spacing in units of Ångströms (Å). One Ångström = 10–10 meter (m) = 0.1 nanometer (nm).  
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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).  
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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.  
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SIGNIFICANCE AND USE
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).  
4.3 SEM-EDS data can be useful in:  
4.3.1 Layer Elucidation—SEM images provide insight into the layer structure of a sample.  
4.3.2 Texture Elucidation—SEM images and elemental maps provide insight into the texture (for example, surface topography, distribution of inclusions).  
4.3.3 Element Identification—Determination of the elements detected in a sample layer.  
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
    8 pages
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ASTM
ASTM E2825-21(Guide)
Standard Guide for Forensic Digital Image Processing

SIGNIFICANCE AND USE
5.1 Processed images are used for many purposes by the forensic science community. They can yield information not readily apparent in the original image, which can assist an expert in drawing a conclusion that might not otherwise be reached.  
5.2 This guide addresses image processing and related legal considerations in the following three categories:  
5.2.1 Image enhancement,  
5.2.2 Image restoration, and  
5.2.3 Image compression.
SCOPE
1.1 This guide provides digital image processing guidelines to ensure the production of quality forensic imagery for use as evidence in a court of law.  
1.2 This guide briefly describes advantages, disadvantages, and potential limitations of each major process.  
1.3 This standard cannot replace knowledge, skills, or abilities acquired through education, training, and experience, and is to be used in conjunction with professional judgment by individuals with such discipline-specific knowledge, skills, and abilities.  
1.4 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.  
1.5 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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    6 pages
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  • Guide
    6 pages
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