ASTM E2225-02

Standard Guide for Forensic Examination of Fabrics and Cordage

SIGNIFICANCE AND USE
The construction, composition and color of textiles as evidence in crimes are useful comparison characteristics for forensic examinations. Textiles appear in a variety of weaves, knits, and nonwoven constructions; a combination of fabric types can occur in any one textile. There is a vast range of colors in which textiles are offered in the marketplace. Therefore, the construction, composition, and color of a textile can aid the Examiner in including or excluding a textile for consideration in a forensic examination.
A comprehensive forensic fabric or cordage examination should consist of a complete characterization of the construction and materials used in the composition of the item (such as sewing thread).
SCOPE
1.1 The intent of this guide is to assist individuals and laboratories conducting examinations of fabrics and cordage. It is not designed as a detailed methods description or protocol for the analysis and comparison of fabric and cordage evidence, but as a guide to an acceptable procedure to strengthen the usefulness of the analytical method.

General Information

• Status: Historical
• Publication Date: 09-Jul-2002
• ICS: 07.140 - Forensic science
• ICS: 59.080.30 - Textile fabrics
• Technical Committee: E30 - Forensic Sciences
• Drafting Committee: E30.01 - Criminalistics

Relations

• Replaced By: ASTM E2225-10 - Standard Guide for Forensic Examination of Fabrics and Cordage
• Effective Date: 15-Sep-2010
• Referred By: ASTM E1732-22 - Standard Terminology Relating to Forensic Science
• Effective Date: 10-Jul-2002
• Referred By: ASTM E3260-21 - Standard Guide for Forensic Examination and Comparison of Pressure Sensitive Tapes
• Effective Date: 10-Jul-2002

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation:E2225–02
Standard Guide for
Forensic Examination of Fabrics and Cordage
This standard is issued under the fixed designation E2225; 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 3.10 staple fiber—natural fibers or cut lengths from fila-
ments.
1.1 The intent of this guide is to assist individuals and
3.11 strand—filaments or yarns twisted together or laid
laboratories conducting examinations of fabrics and cordage. It
parallel to form a unit for further twisting or plaiting into
is not designed as a detailed methods description or protocol
cordage.
for the analysis and comparison of fabric and cordage evi-
3.12 tracer—a marker (such as color-coded yarns or labels)
dence, but as a guide to an acceptable procedure to strengthen
integrated into the manufacture of a cord that assists in
the usefulness of the analytical method.
identifying the manufacturer.
2. Referenced Documents
3.13 twist direction (lay)—the direction of twist in yarns is
indicated by the capital letters S and Z.Yarn with an S-twist is
2.1 ASTM Standards:
seen when a yarn is held vertically and the plies spiral around
E1459 Guide for Physical Evidence Labeling and Related
itscentralaxisslopeinthesamedirectionasthemiddleportion
Documentation
of the letter S, and Z-twist is seen when the plies slope in the
E1492 Practice for Receiving, Documenting, Storing, and
same direction as the middle portion of the letter Z.
Retrieving Evidence in a Forensic Science Laboratory
3.14 wale—a column of loops lying lengthwise in a knit
E2228 Guide for Microscopic Examination of Textile Fi-
fabric.
bers
3.15 warp—the set of yarn in all woven fabrics that runs
3. Terminology
lengthwise and parallel to the selvage and is interwoven with
the filling.
3.1 cordage—twine, ropes, and cords, collectively.
3.16 weft(filling)—inawovenfabric,theyarnrunningfrom
3.2 core—fibers or other textile materials running length-
selvage to selvage at right angles to the warp.
wise through the center of a cordage.
3.17 woven fabric—generally used to refer to fabric com-
3.3 course—the row of loops or stitches running across a
posed of two sets of yarns, warp and weft (filling), that is
knit fabric, corresponding to the filling in woven fabrics.
formed by weaving, which is the interlacing of these sets of
3.4 crown—the raised portion of a strand in a twisted
yarns.
cordage.
3.18 yarn—filaments (fibers) with or without a twist used to
3.5 fabric—a planar textile structure produced by interlac-
form a strand.
ing yarns, fibers, or filaments.
3.6 knit fabric—a structure produced by interlocking one or
4. Summary of Guide
more loops of yarn or comparable material.
4.1 Due to the general availability of fabric and cordage,
3.7 pitch—the number of crowns per inch of the same
they are often encountered by the forensic scientist. This guide
strand.
assists the forensic scientist in determining and documenting
3.8 ply—the number of single yarns twisted together to
the structural details of fabric and cordage such as design,
form a plied cord; an individual yarn in a plied yarn or cord.
construction and composition. These structural details can
3.9 selvage—the narrow edge of woven fabric that runs
often provide information of significant forensic value.
parallel to the warp. It is made with stronger yarns in a tighter
construction than the body of the fabric to prevent raveling.
5. Significance and Use
5.1 The construction, composition and color of textiles as
This guide is under the jurisdiction of ASTM Committee E30 on Forensic
evidence in crimes are useful comparison characteristics for
Sciences and is the direct responsibility of Subcommittee E30.01 on Criminalistics.
forensic examinations. Textiles appear in a variety of weaves,
Current edition approved July 10, 2002. Published August 2002. DOI: 10.1520/
E2225-02. knits, and nonwoven constructions; a combination of fabric
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
types can occur in any one textile. There is a vast range of
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
colors in which textiles are offered in the marketplace. There-
Standards volume information, refer to the standard’s Document Summary page on
fore, the construction, composition, and color of a textile can
the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
E2225–02
aid the Examiner in including or excluding a textile for knownpieces(so-called“longsandshorts”)providesadetailed
consideration in a forensic examination. corroborative description.
5.2 A comprehensive forensic fabric or cordage examina- 7.2.1 If a physical match is not possible, comparison of the
tion should consist of a complete characterization of the parameters determined in the checklist will assist the Examiner
construction and materials used in the composition of the item in determining if the two items could have originated from the
(such as sewing thread). same source.
7.3 Fabric:
6. Sample Handling
7.3.1 Fabric examinations are primarily a process of decon-
6.1 Photographs may be taken of the item prior to conduct-
structing the fabric by dissecting its constituent elements. Each
ing any analyses in order to provide documentation of the
of these elements can have a number of sub-elements, all of
original condition. Document and remove other evidence (for
which must be characterized to complete the examination.
example, hair, blood, paint, etc.) which may require additional
These elements include:
analysis. Document any physical damage (for example, worn,
7.3.1.1 Construction (woven, knit, nonwoven),
cut, broken, frayed, etc.). The following general macroscopic
7.3.1.2 Threads per inch in warp and weft direction,
characteristics should be observed and documented:
7.3.1.3 Staple or continuous fibers in yarns,
6.1.1 Severed ends for possible physical matches,
7.3.1.4 Yarn twist,
6.1.2 Knots or ligatures, or both,
7.3.1.5 Number of plies,
6.1.3 Dimensions (size, length, diameter, etc.),
7.3.1.6 Direction of twist of plies,
6.1.4 Components: number, type, and twist, and
7.3.1.7 Number of filaments in each ply,
6.1.5 Color (dyed/natural).
7.3.1.8 Composition of yarn,
6.2 Do not bring a questioned specimen (for example, a
7.3.1.9 All fiber types composing the fabric,
piece of fabric, yarn, tuft of fibers, etc.) in contact with the
7.3.1.10 Color(s) and design,
known fabric from which it is suspected to have originated
7.3.1.11 Blend of two or
...