ASTM E2228-23a

Standard Guide for Microscopical Examination of Textile Fibers

SIGNIFICANCE AND USE
4.1 Microscopical examination is generally a non-destructive, rapid, and reproducible means of determining the microscopic characteristics, optical properties, and generic polymer type of textile fibers.  
4.2 Side-by-side microscopical comparisons provide a highly discriminating and efficient method of determining if two or more fibers can be differentiated.  
4.3 This guideline requires specific pieces of instrumentation outlined herein.
SCOPE
1.1 This standard covers guidelines for microscopical examinations employed in forensic fiber classification, identification, and comparison. The microscopical examination of fibers includes the use of a variety of light microscopes, such as stereomicroscopes, compound microscopes, and comparison microscopes, as well as a variety of illumination types, such as bright field, polarized light, fluorescence, and interference. In certain instances, the scanning electron microscope can yield additional information. The particular test(s) or techniques employed by each examiner or laboratory will depend upon available equipment, examiner training, and the nature and extent of the fiber evidence.  
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.3 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.  
1.4 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.

General Information

• Status: Published
• Publication Date: 30-Apr-2023
• ICS: 37.020 - Optical equipment
• Technical Committee: E30 - Forensic Sciences
• Drafting Committee: E30.01 - Criminalistics

Standards Content (Sample)

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: E2228 − 23a An American National Standard
Standard Guide for
1
Microscopical Examination of Textile Fibers
This standard is issued under the fixed designation E2228; 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 D276 Test Methods for Identification of Fibers in Textiles
3
(Withdrawn 2021)
1.1 This standard covers guidelines for microscopical ex-
E620 Practice for Reporting Opinions of Scientific or Tech-
aminations employed in forensic fiber classification,
nical Experts
identification, and comparison. The microscopical examination
E1459 Guide for Physical Evidence Labeling and Related
of fibers includes the use of a variety of light microscopes, such
Documentation
as stereomicroscopes, compound microscopes, and comparison
E1492 Practice for Receiving, Documenting, Storing, and
microscopes, as well as a variety of illumination types, such as
Retrieving Evidence in a Forensic Science Laboratory
bright field, polarized light, fluorescence, and interference. In
E1732 Terminology Relating to Forensic Science
certain instances, the scanning electron microscope can yield
E2917 Practice for Forensic Science Practitioner Training,
additional information. The particular test(s) or techniques
Continuing Education, and Professional Development
employed by each examiner or laboratory will depend upon
Programs
available equipment, examiner training, and the nature and
4
2.2 AATCC Standards:
extent of the fiber evidence.
AATCC Test Methods 20 Fiber Identification: Qualitative
1.2 The values stated in SI units are to be regarded as
2.3 Other Documents:
5
standard. No other units of measurement are included in this
ISO 17025 Testing and calibration laboratories
standard.
3. Terminology
1.3 This standard is intended for use by competent forensic
science practitioners with the requisite formal education, 3.1 Definitions—For definitions of terms used in this guide,
refer to Terminology D123 and E1732.
discipline-specific training (see Practice E2917), and demon-
strated proficiency to perform forensic casework.
3.2 Definitions of Terms Specific to This Standard:
1.4 This standard does not purport to address all of the 3.2.1 anisotropic, adj—a characteristic of an object in which
safety concerns, if any, associated with its use. It is the
the refractive index differs depending on the direction of
responsibility of the user of this standard to establish appro-
propagation or vibration of light through the object.
6
priate safety, health, and environmental practices and deter-
(1)
mine the applicability of regulatory limitations prior to use.
3.2.2 barrier filter, n—a filter used in fluorescence micros-
1.5 This international standard was developed in accor-
copy that absorbs excitation energy that has been reflected by
dance with internationally recognized principles on standard-
the sample, selectively transmitting only wavelengths of light
ization established in the Decision on Principles for the
greater than the cut-off wavelength, or within a specific
Development of International Standards, Guides and Recom-
wavelength range.
mendations issued by the World Trade Organization Technical
3.2.3 Becke line, n—the bright halo near the boundary of a
Barriers to Trade (TBT) Committee.
fiber that moves with respect to that boundary as the micro-
2. Referenced Documents scope is focused through best focus when the fiber is mounted
2
in a medium that differs from its refractive index.
2.1 ASTM Standards:
(1)
D123 Terminology Relating to Textiles
1 3
This guide is under the jurisdiction of ASTM Committee E30 on Forensic The last approved version of this historical standard is referenced on
Sciences and is the direct responsibility of Subcommittee E30.01 on Criminalistics. www.astm.org.
4
Current edition approved May 1, 2023. Published May 2023. Originally Available from American Association of Textile Chemists and Colorists
approved in 2002. Last previous edition approved in 2023 as E2228 – 23. DOI: (AATCC), P.O. Box 12215, Research Triangle Park, NC 27709-2215, http://
10.1520/E2228-23A. www.aatcc.org.
2 5
For referenced ASTM standards, visit the ASTM website, www.astm.org, or Available from American National Standards Institute (ANSI), 25 W. 43rd St.,
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM 4th Floor, New York, NY 10036, http://www.ansi.org.
6
Standards volume information, refer to the standard’s Document Summary page on The boldface n
...

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. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: E2228 − 23 E2228 − 23a An American National Standard
Standard Guide for
1
Microscopical Examination of Textile Fibers
This standard is issued under the fixed designation E2228; 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
1.1 This standard describescovers guidelines for microscopical examinations employed in forensic fiber characterization,
classification, identification, and comparison. AThe microscopical fiber examination can include examination of fibers includes the
use of a variety of light microscopes, such as stereomicroscope, polarized light, comparison, stereomicroscopes, compound
microscopes, and comparison microscopes, as well as a variety of illumination types, such as bright field, polarized light,
fluorescence, and interference. In certain instances, the scanning electron microscope can yield additional information. The
particular test(s) or techniques employed by each examiner or laboratory will depend upon available equipment, examiner training,
and the nature and extent of the fiber evidence.
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
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,is intended for use
by competent forensic science practitioners with the requisite formal education, discipline-specific training (see Practice E2917
and abilities.), and demonstrated proficiency to perform forensic casework.
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.
2. Referenced Documents
2
2.1 ASTM Standards:
D123 Terminology Relating to Textiles
3
D276 Test Methods for Identification of Fibers in Textiles (Withdrawn 2021)
E620 Practice for Reporting Opinions of Scientific or Technical Experts
E1459 Guide for Physical Evidence Labeling and Related Documentation
E1492 Practice for Receiving, Documenting, Storing, and Retrieving Evidence in a Forensic Science Laboratory
E1732 Terminology Relating to Forensic Science
E2917 Practice for Forensic Science Practitioner Training, Continuing Education, and Professional Development Programs
1
This guide is under the jurisdiction of ASTM Committee E30 on Forensic Sciences and is the direct responsibility of Subcommittee E30.01 on Criminalistics.
Current edition approved April 1, 2023May 1, 2023. Published May 2023. Originally approved in 2002. Last previous edition approved in 20222023 as
E2228 – 22a.E2228 – 23. DOI: 10.1520/E2228-23.10.1520/E2228-23A.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
3
The last approved version of this historical standard is referenced on www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
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E2228 − 23a
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2.2 AATCC Standards:
AATCC Test Methods 20 Fiber Identification: Qualitative
2.3 Other Documents:
5
ISO 17025 Testing and calibration laboratories
3. Terminology
3.1 Definitions—For definitions of terms used in this guide, refer to Terminology D123 and E1732.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 anisotropic, adj—a characteristic of an object in which the refractive index differs depending on the direction of propagation
or vibration of light through the object.
6
(1)
3.2.2 barrier filter, n—a filter used in fluorescence microscopy that suppresses unnecessary a
...