OSAC 2022-S-0019 Standard Guide for 

Forensic Examination of Fibers

1

OSAC 2022-S-0019

Standard Guide for

Forensic Examination of 

Fibers

Trace Materials Subcommittee

Chemistry: Trace Evidence Scientific Area Committee 

Organization of Scientific Area Committees (OSAC) for Forensic Science
OSAC 2022-S-0019 Standard Guide for 

Forensic Examination of Fibers

2

OSAC Proposed Standard

OSAC 2022-S-0019 Standard Guide 

for Forensic Examination of Fibers

Prepared by 

Trace Materials Subcommittee

Version: 1.0 - OSAC Open Comment

March 2022

Disclaimer:

This OSAC Proposed Standard was written by the Trace Materials Subcommittee of the Organization of 

Scientific Area Committees (OSAC) for Forensic Science following a process that includes an open 

comment period. This Proposed Standard will be submitted to a standards developing organization and is 

subject to change. 

There may be references in an OSAC Proposed Standard to other publications under development by 

OSAC. The information in the Proposed Standard, and underlying concepts and methodologies, may be 

used by the forensic-science community before the completion of such companion publications.

Any identification of commercial equipment, instruments, or materials in the Proposed Standard is not a 

recommendation or endorsement by the U.S. Government and does not imply that the equipment, 

instruments, or materials are necessarily the best available for the purpose.

To be placed on the OSAC Registry, certain types of standards first must be reviewed by a Scientific and 

Technical Review Panel (STRP). The STRP process is vital to OSAC’s mission of generating and 

recognizing scientifically sound standards for producing and interpreting forensic science results. The 

STRP shall provide critical and knowledgeable reviews of draft standards or of proposed revisions of 

standards previously published by standards developing organizations (SDOs) to ensure that the 

published methods that practitioners employ are scientifically valid, and the resulting claims are 

trustworthy.

The STRP panel will consist of an independent and diverse panel, including subject matter experts, 

human factors scientists, quality assurance personnel, and legal experts, which will be tasked with 

evaluating the proposed standard based on a comprehensive list of science-based criteria.

For more information about this important process, please visit our website 

at: https://www.nist.gov/topics/organization-scientific-area-committees-forensic-science/scientifictechnical-review-panels. 
OSAC 2022-S-0019 Standard Guide for 

Forensic Examination of Fibers

1

Standard Guide for Forensic Examination of Fibers

1. Scope 

1.1 This document is an introduction to the examination of textile fibers in forensic casework. It is intended to 

assist individuals who conduct fiber analyses in their evaluation, selection, and application of tests that can be of value 

to their examinations. The goal is to provide a consistent approach to fiber analysis. Detailed descriptions of 

procedures for many of the techniques are addressed in separate documents (E2224, E2225, E2227, E2228). This 

document is not intended as a detailed process description or rigid scheme for the analysis and comparison of fibers, 

but as a guide to the strengths and limitations of each analytical technique. 

1.2 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. 

1.3 This guide 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.

1.4 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 

2.1 ASTM Standards:1

D123 Terminology Relating to Textiles

D629 Standard Test Methods for Quantitative Analysis of Textiles

D4845 Terminology Relating to Wool

D4849 Standard Terminology Related to Yarns and Fibers

D7641 Guide for Textile Fibers

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

E2224 Guide for Forensic Analysis of Fibers by Infrared Spectroscopy

E2225 Guide for Forensic Examination of Fabrics and Cordage

E2227 Guide for Forensic Examination of Non-Reactive Dyes in Textile Fibers by Thin-Layer 

Chromatography

E2228 Guide for Microscopical Examination of Textile Fibers

E2917 Practice for Forensic Science Practitioner Training, Continuing Education, and Professional 

Development Programs

OSAC 2022-S-0029 Standard Guide for Interpretation and Reporting in Forensic Comparisons of Trace 

Materials

WK 78748 Practice for a Forensic Fiber Training Program

WK 78749 Guide for Microspectrophotometry in Forensic Fiber Analysis

2.2 AATCC Standards:2

AATCC Test Method 20: Qualitative Test Method 20–2013 Fiber Analysis: Qualitative 

1 For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual 

Book of ASTM Standards volume information, refer to the standard’s Document Summary page on the ASTM website.

2 Available from American Association of Textile Chemists and Colorists (AATCC), P.O. Box 12215, Research Triangle Park, NC 27709-2215, 

http://www.aatcc.org.
OSAC 2022-S-0019 Standard Guide for 

Forensic Examination of Fibers

2

2.3 Other Documents:

ANAB ANSI 31253

ISO/IEC 17025 General Requirements for the Competence of Testing and Calibration Laboratories4

SWGMAT Introduction to Forensic Fiber Examination

3. Terminology 

3.1 Definitions— For additional terms commonly employed for fiber examinations, see E1732 and E2228. For 

additional terms relating to textiles and wool, see D123, D4845, and D7641.

3.2 Definitions of Terms Specific to This Standard:

3.2.1 animal fiber, n—any natural protein-based fiber. D7641

 3.2.2 exclusionary difference, n—A difference in one or more characteristics between compared items that is 

sufficient to determine that the compared items did not originate from the same source, are not the same substance, 

or do not share the same composition or classification. (OSAC Preferred Term – Lexicon)

 3.2.2.1 Discussion—What is sufficient depends on the performance and limitations of the method used on the 

material in question.

3.2.3 generic class, n—as used with textile fibers, a grouping having similar chemical compositions or specific 

chemical characteristics. D123

3.2.4 inorganic fibers, n—a class of fibers of natural mineral origin (for example, chrysotile asbestos) and 

manmade mineral origin (for example, fiberglass). E2228

3.2.5 manufactured fiber, n—a class name for various genera of fibers (including filaments) produced from fiber 

forming substances which can be (1) polymers synthesized from chemical compounds [synthetic fibers], (2) 

modified or transformed natural polymers [regenerated fibers], and (3) minerals, for example, glasses. E2228

3.2.5.1 Discussion—Acrylic, nylon, polyester, olefin, urethane, and polyvinyl are examples of fiber 

synthesized from chemical compounds. Cellulose based fibers, such as acetate and rayons, and alginate fibers are 

examples of modified or transformed polymers. D123

3.2.6 natural fibers, n—a class name for various genera of fibers (including filaments) of: (1) animal (that is, 

silk and wool); (2) mineral (that is, asbestos); or (3) vegetable origin (that is, cotton, flax, jute, and ramie). E2228

3.2.7 synthetic fibers, n—a class of manufactured polymeric fibers, which are synthesized from chemical 

compounds (for example, nylon and polyester). 

3.2.8 target fibers, n—questioned fibers that an examiner selects for further examination based on their 

resemblance to the known sample. 

3.2.9 technical review, n—a qualified second party’s evaluation of reports, notes, data, and other documentation 

to ensure there is appropriate and sufficient support for the actions, results, conclusions, opinions, and 

interpretations. (OSAC Preferred Term – Lexicon)

3.2.9 textile, n—a general term for fibers, yarn intermediates, yarns, fabrics, and products that retain all the 

strength, flexibility, and other typical properties of the original fiber or filaments.

3.2.10.1 Discussion—General, a structure made from any combination of natural or manufactured fibers, 

having either a measured staple length or a continuous filament length, that can be in the form of a woven, 

nonwoven, braided, plaited, knitted, entangled or twisted product and which retains its characteristic flexibility and 

drape. Specific, as applied to: (1) staple fibers and filaments suitable for conversion to or use as yarns, or for the 

preparation of nonwoven fabrics, (2) yarns made from natural or manufactured fibers, (3) fabrics and other 

manufactured products made from fibers as defined above, and form yarns, and (4) garments and other articles 

fabricated wholly from one or more of the above, and articles made principally from the above when the products 

retain the characteristic flexibility and drape of the original fabrics. D123

3.2.11 textile fiber, n—a generic term for the various types of matter that can be transformed into a yarn having 

a length, at least 100 times its diameter, and which can be used to produce a flexible structure by weaving; knitting; 

braiding; felting or any other means of processing. 

3.2.11.1 Discussion—The matter transformed into a textile fiber can be either natural or manufactured. In 

addition to having a high ratio of length to thickness, the textile fiber also needs to have sufficient strength, 

3 Available from ANSI National Accreditation Board, 330 E. Kilbourn Ave, Suite 926, Milwaukee, WI, 53202, https://anab.ansi.org/2018-isoiec-17025-forensic-accreditation-documents-0.

4 Available from International Organization for Standardization (ISO), ISO Central Secretariat, BIBC II, Chemin de Blandonnet 8, CP 401, 1214 

Vernier, Geneva, Switzerland, http://www.iso.org.
OSAC 2022-S-0019 Standard Guide for 

Forensic Examination of Fibers

3

cohesiveness, and flexibility.

3.2.12 verification, n—provision of objective evidence that a given item fulfills specified requirements. 

ISO/IEC 17025 (2017)

3.2.12.1 Discussion—The process through which the analyses of a forensic examiner are compared by a 

second, independent examiner so that the findings of the first examiner are corroborated, or can be corrected in 

situations where there is a disagreement. Verifications can be open or blind. Blind verifications are more robust than 

open verifications.

4. Summary of Guide 

4.1 The basic activities involved in a fiber examination include case assessment, the search for and collection of 

fibers, preparation of the sample(s) for analysis, analysis using appropriate techniques, and evaluation of results.

4.2 The analysis of evidentiary fiber samples includes the examination of physical characteristics, including color, 

optical properties, spectral properties, and chemical composition. The techniques described in this document provide 

complementary information and should be selected and employed in an order that considers sample preservation and 

the amount of discriminating information that can be obtained.

5. Significance and Use 

5.1 Fibers are frequently encountered in casework, whether it be through the evidentiary item itself (e.g., clothing, 

rope), or through the processing and collection of fibers from evidentiary items. Fibers can be exchanged between 

individuals, between individuals and objects, and between objects. 

5.2 Fibers are subjected to a variety of manufacturing processes in order to produce textile materials for application 

in a wide range of industries (e.g., automotive, clothing, home furnishing). Factors such as end use, current trends, 

and availability influence the type, color, and frequency of fibers incorporated into textiles.

5.3 Fibers exhibit a wide range of physical characteristics, including color, optical properties, spectral properties, 

and chemical compositions due to the manufacturing process, end use, and exposure to post-manufacturing changes 

(e.g. exposure to various environmental conditions, chemicals, etc.). These characteristics and properties are observed, 

analyzed, and compared during a fiber examination.

6. Case Assessment

6.1 In the case assessment phase, the examiner determines what samples are to be analyzed. Sample size, sample 

variability, sample condition, environmental effects, evidential value (e.g. are the persons of interest known to have 

contact prior to incident), and collection and packaging techniques are all taken into account. The examiner chooses 

analytical techniques, sample preparation schemes, testing sequences, and degree of sample alteration and 

consumption that are suitable to the specific case.

6.2 Fiber examination involves the observation and interpretation of data, therefore opportunities for bias exist (1-

3). Measures to address the effects of potential bias can include:

6.2.1 Receiving adequate training to conduct fiber examinations (refer to WK78748 Practice for a Forensic Fiber 

Training Program), including cognitive bias and methods that can mitigate or help avoid the effects of biasing 

information and procedures. 

6.2.2 Avoiding task-irrelevant information (e.g., suspect’s confession or investigator’s opinions).

6.2.3 As practicable, evaluating questioned fibers prior to known fiber samples during the examination process. 

6.2.4 Employing a quality assurance program that complies with International Standards such as ISO 17025.

6.2.5 Conducting verification and technical review.

7. Evidence Handling 

7.1 Follow the general requirements set forth in Practice E1492 and Guide E1459 if handling and tracking 

evidence.

7.2 Each laboratory develops appropriate procedures concerning sample size, collection, packaging, preservation, 

and order of examinations in order to prevent contamination and loss of fibers (4, 5).

7.2.1 Collect evidentiary items as soon as possible to mitigate the loss of fibers and other types of trace evidence.

7.2.2 Handling or transport can alter the location of a transferred fiber on a particular item of evidence (6).
OSAC 2022-S-0019 Standard Guide for 

Forensic Examination of Fibers

4

7.3 Multiple kinds of evidence requiring the expertise of different disciplines can be present on a single item. This 

can include various types of trace materials (e.g., hairs, fibers, paint, glass, explosives), as well as fingerprints and 

DNA. Prior to processing an item, consider the types of evidence potentially present and the impact that fiber 

examinations can have on future analyses. Examiners from different sub-disciplines may confer before work is 

undertaken to ensure proper examination order and recovery of evidence. Unless circumstances dictate otherwise, 

the trace materials are collected and preserved prior to other examinations (4, 5). 

7.4 Samples are collected in a manner consistent with generally-recognized and accepted sampling techniques.

8. Types of Examinations 

8.1 During a fiber examination, two basic types of analysis are conducted. These analyses include fiber-type 

identification and fiber comparison (7-9).

8.2 Fiber-type identifications are performed to provide investigative leads and possible end-use information. The 

Federal Trade Commission has defined classifications to include manufactured fiber definitions (Table 1), and fibers 

are analyzed to determine to which generic class (e.g., cotton, polyester) they belong (10). This examination relies 

on analytical techniques to place the questioned fiber into a generic class. There are two broad categories of 

classification: natural fibers and manufactured fibers. Each can be further broken down into sub-classifications. 

8.2.1 Natural fibers are obtained from plants, animals, or mineral materials.

8.2.2 Manufactured fibers can be further described as regenerated, synthetic, or mineral based on the 

starting materials used to form the fibers.

8.3 Fiber comparisons are conducted to determine if a questioned fiber exhibits the same physical characteristics, 

including color, optical properties, spectral properties, and chemical composition as fiber(s) comprising part or all of 

a known sample to assess whether the known sample can or cannot be included as a possible source. The same 

process can also be used to compare two or more questioned fibers in order to determine if they could share a 

common source. 

8.4 The fiber types found at a crime scene or on a person of interest affects their evidential value. 

8.4.1 Certain types of fibers, such as colorless cotton and indigo-dyed blue cotton (denim), are so common as to 

be of limited evidential value, except in rare cases (e.g., colorless cotton fibers embedded or fused on to a deployed 

airbag or a scrap of blue denim fabric caught on the undercarriage of a vehicle suspected to be involved in a hit-andrun).

9. Procedure

9.1 Select sample(s) representative of the observed variation (e.g., color, texture, luster) within a textile to serve as 

a known reference of the material. Differences could arise in measurements of fiber samples from the same garment 

or textile because of differences in weathering (e.g., sunlight exposure), spot staining/bleaching, or repaired areas 

(e.g., use of a fabric marker to cover a discolored area, application of a patch). 

9.2 Techniques for the identification and comparison of fibers (13-18) are found in Table 2 (shaded boxes represent 

techniques which are highly recommended) and are presented in no particular order. Some techniques allow greater 

discrimination between apparently similar samples than others (19-27). The particular technique(s) employed by each 

examiner or laboratory will depend upon available equipment and the nature and extent of the fiber evidence in each 

specific case. 

9.3 For any given fiber identification and comparison, not all the techniques listed in Table 2 are necessary. Fiber 

type, sample size, and condition should be considered if determining which techniques to use. Those requiring more 

sample preparation or consumption should be performed after less-destructive techniques. If sample size is limited, 

nondestructive techniques are exhausted before subjecting the sample to tests which could permanently alter or 

destroy the sample [e.g., Fourier-transform infrared (FTIR) spectroscopy, pyrolysis]. If an exclusionary difference is 

found at any point during the fiber comparison process, then no further analysis is necessary. 

9.4 The analytical tests performed are left to the discretion of the examiner; however, at a minimum, a fiber examiner 

employs a stereomicroscope, light microscope, and a polarized light microscope for identification. In addition, the 

fiber examiner uses a comparison microscope and at least one other color comparison technique if performing fiber 

comparisons. 

9.4.1 Using the comparison microscope, an examiner views fibers side-by-side at the same magnifications in 

visible light, and by alternative lighting, such as polarized light or fluorescence, if the equipment allows. For color 
OSAC 2022-S-0019 Standard Guide for 

Forensic Examination of Fibers

5

comparison, an examiner employs at least one analytical test [e.g., microspectrophotometry (MSP), thin layer 

chromatography (TLC)] along with comparison microscopy. Fourier-transform infrared spectroscopy (or another 

technique which provides comparable chemical information) is strongly recommended for the characterization of 

manufactured fibers. 

9.4.2 A typical fiber examination workflow is shown in Figure 1. This figure represents one of several possible 

workflows used to identify and compare fibers and does not preclude the use of other workflows to perform fiber 

examinations. General descriptions of techniques employed during a fiber examination are listed in sections 9.5 

through 9.8 to provide additional guidance for the selection of appropriate techniques. 

9.5 Microscopical Examinations 

9.5.1 Microscopical examinations provide information about the physical and optical properties of a fiber, 

allowing for the determination of general fiber type and the differentiation of fiber samples. 

9.5.1.1 Low-magnification stereomicroscopy is used for the search, recognition, manipulation, and collection 

of apparent textile fibers. This technique also offers a limited characterization of the fiber’s physical characteristics.

9.5.1.2 High-magnification light microscopy is employed to characterize the fiber’s physical and microscopic 

characteristics (e.g., color, diameter, cross-sectional shape, pigment, voids, inclusions).

9.5.1.3 Comparison microscopy allows the examiner to view two fiber samples side-by-side while employing 

the same magnification and lighting conditions. Comparison using polarized light or fluorescence is performed if the 

equipment allows.

9.5.1.4 Polarized light microscopy (PLM), an essential part of the fiber examination process, is used to observe 

and measure the optical properties of a fiber. These properties are imparted during the manufacturing process and are 

used to determine the general fiber type (e.g., acrylic, nylon, polyester).

9.5.1.5 Fluorescence microscopy is a technique used to observe the optical properties of the fiber itself as well 

as those imparted to the fiber by various dyes, optical brighteners, chemical treatment/damage or contaminants.

9.5.2 Strengths of microscopical examination techniques include: 

● Highly discriminating and reliable 

● Generally non-destructive 

● Rapid

● Requires minimal sample preparation 

9.5.3 Limitations of microscopical examination techniques include:

● Physical and optical properties of fibers can be impacted by sample handling, physical 

damage or environmental factors 

● Very dark fibers can impede the ability of these techniques to resolve physical and optical 

properties of fiber samples 

● Potential for quenching of fiber samples when performing fluorescence microscopy

9.5.4 For more detailed information regarding microscopical examination of fibers, refer to ASTM E2228 Guide 

for Microscopical Examination of Textile Fibers.

9.6 Color Examinations

9.6.1 Color is highly variable among textiles. Dyes and pigments belong to numerous chemical categories with 

more than a dozen different application techniques (28, 29). Color is a highly discriminating characteristic due to the 

variety of dye productions, batch variations, and the multitude of colors available. Individual fibers can be colored 

before being spun into yarn, yarns can be dyed after being spun, or the fabric can be dyed after its construction as a 

fabric or garment (28-31). Color can also be applied to the surface of a fabric by printing. The absorption of the dye 

along the fiber length can vary based on the dyes, dyeing processes used, and the fiber type. 

9.6.2 For color comparison, an examiner employs comparison microscopy along with another analytical 

technique, such as MSP or TLC. If another analytical technique is not performed, the reason is documented.

9.6.3 Microspectrophotometry is an instrumental technique that provides color measurement data for fibers using 

transmitted light. During fiber examinations, the absorption of visible light is measured and compared. If samples are 

compared and no differences are detected in the visible region, they can be further analyzed in the UV and NIR region 

using MSP. For more detailed information regarding MSP, refer to ASTM WK78749 Guide for 

Microspectrophotometry in Forensic Fiber Analysis. 

9.6.3.1 Strengths of this technique:

● Provides objective color measurement data
OSAC 2022-S-0019 Standard Guide for 

Forensic Examination of Fibers

6

● Generally considered to be non-destructive (note potential for photobleaching below) 

9.6.3.2 Limitations of this technique include:

● Absorption can be impacted by environmental factors, sample handling or physical damage 

● Very dark or very light fibers may display data of limited value in the visible region

● Certain fiber types naturally absorb in the UV region (e.g., wool, polyester), limiting data collection and 

interpretation

● Individual dye components may not be differentiated

● Photobleaching of fiber samples may occur

9.6.4 Thin layer chromatography is a dye analysis technique requiring the extraction of dye from the colored fiber. 

Different dye mixtures can produce similarly-colored fibers that may be difficult to distinguish by optical techniques 

such as MSP. By first extracting the dye and then separating the individual dye components, TLC provides 

complementary information to further discriminate between fiber colorants. For more detailed information regarding 

TLC, refer to ASTM E2227 Guide for Forensic Examination of Non-Reactive Dyes in Textile Fibers by Thin-Layer 

Chromatography.

9.6.4.1 Strengths of this technique include:

● Simple dye analysis technique

● Provides complementary information to MSP

9.6.4.2 Limitations of this technique include 

● Destructive

● Limited by the small amount of dye present in a single fiber 

9.7 Fourier-Transform Infrared Spectroscopy 

9.7.1 Fourier-transform infrared spectroscopy is an instrumental technique that employs the use of infrared 

radiation to obtain information about the chemical structure of fibers in order to determine the fiber-type (e.g., nylon, 

polyester), sub-type (e.g., identification of acrylic fiber co-polymers), and inorganic fillers (if present). FTIR 

spectroscopy is typically employed following microscopical and color examination due to potential alteration of fiber 

morphology. For more detailed information regarding FTIR spectroscopy, refer to ASTM E2224 Guide for the 

Forensic Analysis of Fibers by Infrared Spectroscopy.

9.7.2 Strengths of this technique: 

● Provides chemical structure and fiber-type information

● Requires minimal sample preparation

9.7.3 Limitations of this technique include:

● Sample preparation can alter the physical characteristics of the analyzed portion of the fiber 

● The presence of surface contaminants can interfere with spectral interpretation 

9.8 Additional techniques

9.8.1 Capillary Electrophoresis (CE) is a chromatographic technique used to analyze very small amounts of dye 

from colored fibers (32). 

9.8.1.1 Strengths of this technique include:

● Provides complementary information to MSP 

● More efficient than TLC

9.8.1.2 Limitation of this technique:

● Destructive 

9.8.2 Pyrolysis (Py) is an instrumental technique in which fibers are thermally decomposed, followed by analysis 

using either gas chromatography (Py-GC), mass spectrometry (Py-MS) or a combination of both (Py-GC-MS) to 

identify the fiber-type and sub-type (33). 

9.8.2.1 Strength of this technique:

● Provides fiber-type and sub-type information

9.8.2.2 Limitation of this technique: 

● Destructive

9.8.3 Raman spectroscopy is an instrumental technique that uses a monochromatic source (i.e., a laser emitting a 

wavelength in the ultraviolet, visible or near-infrared spectral range) to produce an inelastic light scattering effect 

which provides information primarily about fiber dyes, pigments, and the polymer, delustrants, and fillers (34).

9.8.3.1 Strengths of this technique include:
OSAC 2022-S-0019 Standard Guide for 

Forensic Examination of Fibers

7

● Provides complementary information to FTIR 

● Requires minimal sample preparation

9.8.3.2 Limitation of this technique:

● Analysis can be hindered by background fluorescence or thermal degradation of the 

sample

9.8.4 High performance liquid chromatography (HPLC) is a chromatographic technique used to analyze dyes 

extracted from short lengths of colored fibers. High performance liquid chromatography employs a micro-extraction 

process that is effective for a wide range of fiber types, dye types, and dye mixtures (35). 

9.8.4.1 Strengths of this technique include:

● Provides quantitative data 

● Offers better resolution of dyes than TLC 

● Effective for a wide range of fiber types, dye types and dye mixtures

● Provides complementary information to further discriminate between fiber colorants 

9.8.4.2 Limitations of this technique include:

● Destructive 

● Separation of various dye types on a single chromatographic system can be difficult 

9.8.5 Elemental analysis techniques such as scanning electron microscopy/energy dispersive X-ray spectroscopy 

(SEM-EDX) and X-ray fluorescence (XRF) can provide information about the elemental composition of fibers (36).

9.8.5.1 Strengths of these techniques include: 

● Provide information about inorganic components imparted to a fiber through the 

manufacturing process, additives/finishing agents, and environmental contaminants 

● SEM-EDX and XRF are complementary techniques; however, XRF is more sensitive to 

higher atomic weight elements

9.8.5.2 Limitations of these techniques include that:

● X-ray production for SEM-EDX is dependent on beam energy, composition and density of 

the sample, and energy of the X-rays 

● Sample preparation (if carbon coated and placed on carbon-taped stub) can hinder analysis 

of samples afterward

● XRF is less sensitive to lower atomic weight elements

9.8.6 Techniques such as cross-sectioning, melting point and solubility can be used to obtain information about the 

physical characteristics and chemical properties of a manufactured fiber (37, 38). It is important to consider the 

sequence of analysis when incorporating these destructive techniques into a fiber examination.

9.8.6.1 Strength of these techniques: 

● Provide information about a manufactured fiber's physical and chemical properties

9.8.6.2 Limitation of these techniques: 

● Destructive 

9.8.7 Additional techniques specific to natural fibers include the drying twist test, ashing, and staining. Crosssectioning can also be used to obtain additional information about a natural fiber’s cross-sectional shape and type. As 

with previously-mentioned techniques, consideration is given to the amount of sample available, and the destructive 

nature of the techniques employed. 

10. Results

10.1 In a fiber case, the examiner analyzes the evidence, interprets the data and observations, and reports an opinion 

of the findings.

10.2 The comparative analysis of two or more fibers involves the evaluation of physical characteristics, including 

color, optical properties, spectral properties, and chemical composition. 

10.2.1 If one or more exclusionary differences are recognized between compared fibers based on the measured or 

observed characteristics, the fibers are distinguishable. In fiber comparisons, this is described as an exclusion or 

elimination: two or more fibers are excluded as having originated from the same source based on the sample provided 

(39).

10.2.2 If no exclusionary differences are recognized between compared fibers based on the measured or observed 

characteristics, the fibers cannot be distinguished by these techniques. In fiber comparisons, this is described as an 
OSAC 2022-S-0019 Standard Guide for 

Forensic Examination of Fibers

8

association of evidence based on class characteristics, indicating the possibility that the fibers originated from the 

same source. Since different fiber sources can share class characteristics, this opinion does not indicate that the fibers 

came from a specific source.

10.3 Refer to the Standard Guide for Interpretation and Reporting in Forensic Comparisons of Trace Materials.

11. Evaluation of the Results

11.1 When a specific item, such as fabric from a person of interest or a crime scene, is included as a possible source 

of a questioned fiber, or if two or more questioned fibers could share a common source, the evidential value is 

dependent upon many factors. 

11.1.1 Source factors 

11.1.1.1 Fiber type. 

11.1.1.2 Intra-source variability (e.g. trunk liner, patchwork garment). 

11.1.1.3 Fiber characteristics. 

11.1.1.4 Condition of a specific source (e.g., shirt recovered from a hit-and-run victim exhibiting damage).

11.1.1.5 Presence of contaminants, damage, or other acquired characteristics (e.g., the questioned fiber exhibits

characteristics of heat exposure and the victim clothing is burned or singed). 

11.1.2 Activity or case-related factors (e.g., transfer and persistence [6, 40-47], efficiency of recovery [4,5])

11.1.2.1 Location, quantity, and acquired characteristics of the recovered fibers (e.g., fibers embedded in a 

deployed airbag, fibers embedded in blood on a weapon). 

11.1.2.2 Number and types of fibers associated to single or multiple sources (e.g., multiple black polyester fibers 

associated to a shirt, multiple blue cotton fibers and multiple blue polyester fibers associated to a single shirt, apparent 

cross transfer of fibers between two shirts).

Note 1: As the number of associated questioned fibers increases, so too does the support for recent and direct contact 

occurring with the known fiber source. The converse is not necessarily true, however, and even one fiber association 

can have evidential value. Finding no fiber associations does not necessarily mean that no contact occurred. 

11.1.2.3 Nature of contact.

Note 2: The type of physical contact between two sources can influence the number of fibers transferred and the 

value placed on their discovery. Brief contact is less likely to transfer multiple fibers than extended and more forceful 

contact. 

11.1.2.4 Composition, construction and condition of a textile. 

Note 3: Tightly-woven or tightly-knit fabrics shed fewer fibers than loosely-knit or loosely-woven fabrics. 

Likewise, fabrics composed of filament fibers shed less than fabrics composed of staple fibers. Newer fabrics can 

have an abundance of loosely-adhering fibers on the surface of the fabric, while worn fabrics can have damaged areas 

that easily shed fibers. Damage to a fabric caused during physical contact can greatly increase the potential of fiber 

transfer.

11.1.2.5 Environmental factors (e.g., fading, discoloration, singeing).

11.2 The ability to discriminate between similar types and colors of recovered fibers is important when assessing 

the significance of an association (19, 20, 23, 24). 

11.3 If information about the relevant fiber population is available (e.g., published discrimination studies, product 

manufacturing and distribution information), the significance of the features recorded during the examination can be 

evaluated (48, 49). 

11.4 The analytical scheme an examiner employs directly impacts the ability to discriminate between fibers and,

ultimately, the significance of findings. If an analytical scheme is not inclusive of the assessment of the physical 

characteristics, including color, optical properties, spectral properties, and chemical composition when applicable, 

then a qualifying statement is necessary.

11.5 Background information regarding the potential sources involved, possible prior contact, and the environment 

where questioned fibers were recovered affects the significance of the association. When practicable, and as 

laboratory practices allow, avoid task-irrelevant information (50, 51).

12. Documentation

12.1 Contemporaneously record all observations made during case assessment and examination. Ensure the 
OSAC 2022-S-0019 Standard Guide for 

Forensic Examination of Fibers

9

examination notes accurately reflect all observations, the evidence analyzed, the techniques employed, and all results. 

Notes should be sufficient to allow an independent analyst to understand and evaluate all the work performed, analyze 

and interpret the data, and reach independent opinions. 

12.2 Case notes include acquired instrumental data that was used to reach a finding. 

12.3 Verifications and technical reviews are performed and documented as per laboratory standard operating 

procedures and quality assurance guidelines.

12.4 Reports are written in accordance with ASTM standards (E620) and include the results of the analysis, an 

interpretation of the results, and qualifying statements that further describe the strengths and limitations of the analysis.

12.5 All documentation conforms to accreditation guidelines as appropriate (e.g., ISO/IEC 17025 [4, 52]), as well 

as the laboratory’s standard operating procedures and quality assurance guidelines.

13. Keywords

Forensic science, fiber, fiber comparison, instrumental analysis.

Table 1 Federal Trade Commission Rules and Regulations Under the Textile Products Identification Act, 16 

CFT Part 303 Pursuant to the provisions of Section 7 of the Act, the following generic names for manufactured 

fibers, together with their respective definitions, are hereby established (10): 

Fiber Name Definition

Acetate A manufactured fiber in which the fiber-forming substance is cellulose acetate. Where not less 

than 92% of the hydroxyl groups are acetylated, the term triacetate may be used as a generic 

description of the fiber. 

Acrylic A manufactured fiber in which the fiber-forming substance is any long chain synthetic polymer 

composed of at least 85% by weight of acrylonitrile units. 

Anidex A manufactured fiber in which the fiber-forming substance is any long chain synthetic polymer 

composed of at least 50% by weight of one or more esters of a monohydric alcohol and acrylic 

acid. 

Aramid A manufactured fiber in which the fiber-forming substance is any long-chain synthetic 

polyamide in which at least 85% of the amide linkages are attached directly to two aromatic 

rings. 

Azlon A manufactured fiber in which the fiber-forming substance is composed of any regenerated 

naturally occurring proteins. 

Elastoester A manufactured fiber in which the fiber-forming substance is a long chain synthetic polymer 

composed of at least 50% by weight of aliphatic polyether and at least 35% by weight of 

polyester, as defined in 303.7(c). 

Fluoropolymer A manufactured fiber containing at least 95% of a long chain polymer synthesized from aliphatic 

fluorocarbon monomers. 

Glass A manufactured fiber in which the fiber-forming substance is glass. 

Lyocel A manufactured fiber composed of precipitated cellulose and produced by a solvent extrusion 

process where no chemical intermediates are formed. 

Melamine A manufactured fiber in which the fiber-forming substance is a synthetic polymer composed of at 

least 50% by weight of a cross-linked melamine polymer. 

Metallic A manufactured fiber composed of metal, plastic-coated metal, metal-coated plastic, or a core 

completely covered by metal. 

Modacrylic A manufactured fiber in which the fiber-forming substance is any long-chain synthetic polymer 

composed of less than 85% but at least 35% by weight of acrylonitrile units. 

Nylon A manufactured fiber in which the fiber-forming substance is any long-chain synthetic 

polyamide in which less than 85% of the amide linkages are attached directly to two aromatic 

rings. 
OSAC 2022-S-0019 Standard Guide for 

Forensic Examination of Fibers

10

Nytril A manufactured fiber containing at least 85% of a long chain polymer of vinylidene dinitrile 

where the vinylidene dinitrile content is no less than every other unit in the polymer chain. 

Novoloid A manufactured fiber containing at least 85% by weight of a cross-linked novolac. 

Olefin A manufactured fiber in which the fiber-forming substance is any long chain synthetic polymer 

composed of at least 85% by weight of ethylene, propylene, or other olefin units. 

PBI A manufactured fiber in which the fiber-forming substance is a long chain aromatic polymer 

having reoccurring imidazole groups as an integral part of the polymer chain. 

PLA A manufactured fiber in which the fiber-forming substance is composed of at least 85% by 

weight of lactic acid ester units derived from naturally occurring sugars. 

Polyester A manufactured fiber in which the fiber-forming substance is any long chain synthetic polymer 

composed of at least 85% by weight of an ester of a substituted aromatic carboxylic acid, 

including but not restricted to substituted terephthalate units and para substituted hydroxybenzoate units. Where the fiber formed by the interaction of two or more chemically distinct 

polymers (of which none exceeds 85% by weight), and contains ester groups as the dominant 

functional unit (at least 85% by weight of the total polymer content of the fiber), 

and which, if stretched at least 100%, durably and rapidly reverts substantially to its unstretched 

length when the tension is removed, the term elasterell-p may be used as a generic 

description of the fiber. 

Rayon A manufactured fiber composed of regenerated cellulose, as well as manufactured fibers 

composed of regenerated cellulose in which substituents have replaced not more than 15% of the 

hydrogens of the hydroxyl groups. Where the fiber is composed of cellulose precipitated from an 

organic solution in which no substitution of the hydroxyl groups takes place and no chemical 

intermediates are formed, the term lyocell may be used as a generic description of the fiber. 

Rubber A manufactured fiber in which the fiber-forming substance is comprised of a natural or synthetic 

rubber, including the following categories: 

(1) A manufactured fiber in which the fiber-forming substance is a hydrocarbon such as natural 

rubber, polyisoprene, polybutadiene, copolymers of dienes and hydrocarbons, or amorphous 

(noncrystalline) polyolefins. 

(2) A manufactured fiber in which the fiber-forming substance is a copolymer of acrylonitrile 

and a diene (such as butadiene) composed of not more than 50% but at least 10% by weight of 

acrylonitrile units. The term lastrile may be used as a generic description for fibers falling within 

this category. 

(3) A manufactured fiber in which the fiber-forming substance is a polychloroprene or a 

copolymer of chloroprene in which at least 35% by weight of the fiber-forming substance is 

composed of chloroprene units. 

Saran A manufactured fiber in which the fiber-forming substance is any long-chain synthetic polymer 

composed of at least 80% by weight of vinylidene chloride units. 

Spandex A manufactured fiber in which the fiber-forming substance is any long-chain synthetic polymer 

composed of at least 85% of a segmented polyurethane. 

Sulfar A manufactured fiber in which the fiber-forming substance is a long chain synthetic polysulfide 

in which at least 85% of the sulfide linkages are attached directly to two aromatic rings. 
OSAC 2022-S-0019 Standard Guide for 

Forensic Examination of Fibers

11

Vinal A manufactured fiber in which the fiber-forming substance is any long chain synthetic polymer 

composed of at least 50% by weight of vinyl alcohol units and in which the total of the vinyl 

alcohol units and any one or more of the various acetal units is at least 85% by weight of the 

fiber. 

Vinyon A manufactured fiber in which the fiber-forming substance is any long chain synthetic polymer 

composed of at least 85% by weight of vinyl chloride units. 

Table 2 Techniques for the identification and comparison of fibers. Shaded boxes represent techniques which 

are highly recommended.

Physical Characterization Optical Properties Microchemical 

Analysis

Color/Dye/Pigment 

Analysis

Instrumental 

Analysis

Stereomicroscopy PLM Solubility Comparison Microscopy FTIR 

(Manufactured 

Fibers)

Light Microscopy/ 

Comparison Microscopy

Light Microscopy/ 

Comparison Microscopy

Staining 

(Natural Fibers)

MSP, TLC or a 

combination of both 

SEM-EDX/XRF 

SEM Fluorescence Microscopy CE PyGC/PyGCMS 

Melting Point Raman Raman 

Physical Test (Dry Twist, 

Ashing, etc.) HPLC
OSAC 2022-S-0019 Standard Guide for 

Forensic Examination of Fibers

12

14. References

(1) Spellman, B.A., Eldridge, H., & Bieber, P. (2022). Challenges to reasoning in forensic science decisions. 

Forensic Science international: Synergy, 4, e100200. https://doi.org/10.1016/j.fsisyn.2021.100200

(2) Eldridge, H., Spellman, B. A., Morgan, J., Busey, T., and Taylor, M. K., “Human Factors Forensic Science 

Sourcebook,” Forensic Science International: Synergy, 2022 Mar 4;4:100219, Online, Available: 

10.1016/j.fsisyn.2022.100219, Access Date 7/22/2022.

(3) Dror, I. E., “Cognitive and Human Factors in Expert Decision Making: Six Fallacies and the Eight Sources 

of Bias," Analytical Chemistry, Vol. 92, No. 12, June 8, 2020, pp. 7998–8004.

(4) Scientific Working Group for Materials Analysis, “Trace Evidence Quality Assurance Guidelines,” FBI 

Publication, Washington, D.C., 1999. Retrieved from: https://archives.fbi.gov/archives/aboutus/lab/forensic-science-communications/fsc/jan2000/swgmat.htm#laboratory%20audits

(5) Scientific Working Group for Materials Analysis, “Trace Evidence Recovery Guidelines,” FBI Publication, 

Washington, D.C., 1999. Retrieved from: 

https://www.asteetrace.org/static/images/pdf/04%20Trace%20Evidence%20Recovery%20Guidelines%20

%28Published%20in%20Forensic%20Science%20Communications%2C%20October%201999%29.pdf

(6) Chewning, D., Deaver, K., and Christensen, A., “Persistence of Fibres on Ski Masks During Transit and 

Processing,” Forensic Science Communications, Vol. 10, No. 3, July 2008.

(7) Koch, S. L., and Nehse, K., “Fibers.” In Desiderio, V. J., Taylor, C. E., and Nic Daéid, N. (Eds.), Handbook 
OSAC 2022-S-0019 Standard Guide for 

Forensic Examination of Fibers

13

of Trace Evidence Analysis, Hoboken: John Wiley& Sons, 2020, pp. 322–376.

(8) Robertson, J., and Roux, C., “From Crime Scene to Laboratory.” In Robertson, J., Roux, C., and Wiggins, K. 

C. (Eds.), Forensic Examination of Fibres, 3rd edition, Boca Raton: CRC Press, 2018, pp. 99-143.

(9) Trejos, T., Koch, S., and Mehltretter, A., “Scientific foundations and current state of trace evidence—a 

review,” Forensic Chemistry, Vol. 18, May 2020. 

(10)Federal Trade Commission Rules and Regulations Under the Textile Products Identification Act, Title 15, 

U.S. Code Section 70, et seq. 16 CFR 303.7.

(11)Textile Exchange, Preferred Fiber & Materials Market Report 2020, accessed at 

https://textileexchange.org/app/uploads/2021/04/Textile-Exchange_Preferred-Fiber-Material-MarketReport_2020.pdf

(12)Textile Exchange, Preferred Fiber & Materials Market Report 2021, accessed at 

https://textileexchange.org/app/uploads/2022/10/Textile-Exchange_PFMR_2022.pdf

(13)Brunner, H., and Coman, B., The Identification of Mammalian Hair, Melbourne: Inkata Press, 1974.

(14)Catling, D. L., and Grayson, J., Identification of Vegetable Fibers, London: Chapman and Hall, 1982.

(15)Goodpaster, J. V., and Liszewski, E. A., “Forensic Analysis of Dyed Textile Fibers,” Analytical and 

Bioanalytical Chemistry, Vol. 394, No. 8, August 2009, pp. 2009-2018.

(16)Grieve, M. C., “Fibres and their examination in forensic science.” In: Maehly, A., and Williams, R. L., 

Forensic Science Progress (Vol. 4), New York: Springer, 1990.

(17)Hall, D., Practical Fiber Identification, Auburn: Auburn University, 1982.

(18)Robertson, J., and Roux, C., “Protocols for fiber examination and initial preparation.” In Robertson, J., 

Roux, C., and Wiggins, K. G., Forensic Examination of Fibres 3rd Edition, Boca Raton: CRC Press, 2018, 

pp. 119-126.

(19)Biermann, T. W., “Blocks of colour IV: the evidential value of blue and red cotton fibres,” Science and 

Justice, Vol. 47, No. 2, 2007, pp. 68-87.

(20)Cassista, A., and Peters, A. D., “Survey of red, green, and blue cotton fibers,” Canadian Society of Forensic 

Science Journal, Vol. 30, No. 4, 1997, pp. 225-231.

(21)Cook, R., and Wilson, C., “The significance of finding extraneous fibres in contact cases,” Forensic 

Science International, Vol. 32, 1986, pp. 267-273.

(22)Houck, M. M., “Inter-comparison of unrelated fiber evidence,” Forensic Science International, Vol. 135, 

No. 2, 2003, pp. 146-149.

(23)Grieve, M. C., Biermann, T. W., and Schaub, K., “The individuality of fibres used to provide forensic 

evidence -- not all blue polyesters are the same,” Science and Justice, Vol. 45, No. 1, 2005, pp. 13-28.

(24)Palmer, R., Hutchinson, W., and Fryer, V., “The discrimination of (non-denim) blue cotton,” Science and 

Justice, Vol. 49, 2009, pp. 12-18.

(25)Was-Gubala, J., “The kinetics of colour change in textile and fibres treated with detergent solutions Part I -

Colour perception and fluorescence microscopy analysis,” Science and Justice, Vol. 49, 2009, pp. 165-169.

(26)Was-Gubala, J., and Grzesiak, E., “The kinetics of colour change in textile and fibres treated with detergent 

solutions Part II - Spectrophotometric measurements,” Science and Justice, Vol. 50, 2010, pp. 55-58.

(27)Wiggins, K. G., Cook R., and Turner, Y. J., “Dye batch variation in textile fibers,” Journal of Forensic 

Sciences, Vol. 33, 1998, pp. 998-1007.

(28)Aspland, J. R., “What are dyes? What is dyeing?” In AATCC Dyeing Primer, Research Triangle Park: 

American Association of Textile Chemists and Colorists, 1981.

(29)Clark, M., Handbook of Textile and Industrial Dyeing: Principles, Processes and Types of Dyes, 

Cambridge: Woodhead Publishing, pp. 20.

(30)Technical Manual of the American Association of Textile Chemists and Colorists, Research Triangle Park: 

AATCC, 2021.

(31)American Home Economics Association, Textiles and Clothing Section, Textile Handbook, Washington, 

DC: The American Home Economics Association, 1985.

(32)Roux C, Morison R, and Maynard P, “Capillary Electrophoresis,” Forensic Examination of Fibres, 3rd 

edition. Robertson J, Roux C, and Wiggins KG, editors. Boca Raton: CRC Press, 2018: 331-339.

(33)Roux C, Morison R, and Maynard P, “Fibre Identification by Pyrolysis Techniques,” Forensic Examination 

of Fibres, 3rd edition. Robertson J, Roux C, and Wiggins KG, editors. Boca Raton: CRC Press, 2018: 311-

317.

(34)Hemmings J, “Raman Spectroscopy of Fibres,” Forensic Examination of Fibres, 3rd edition. Robertson J, 

Roux C, and Wiggins KG, editors. Boca Raton: CRC Press, 2018: 289-307.
OSAC 2022-S-0019 Standard Guide for 

Forensic Examination of Fibers

14

(35)Roux C, Morison R, and Maynard P, “High Performance Liquid Chromatography (HPLC),” Forensic 

Examination of Fibres, 3rd edition. Robertson J, Roux C, and Wiggins KG, editors. Boca Raton: CRC 

Press, 2018: 328-331.

(36)Roux C, Morison R, and Maynard P, “Scanning Electron Microscopy and Elemental Analysis,” Forensic 

Examination of Fibres, 3rd edition. Robertson J, Roux C, and Wiggins KG, editors. Boca Raton: CRC 

Press, 2018: 319-328.

(37)Gaudette B, “The forensic aspects of textile fiber examination,” Forensic Science Handbook, Volume II. 

Saferstein R, editor. Englewood Cliffs, NJ: Prentice-Hall Inc., 1988: 236-237.

(38)Stratmann M, “The Solubility Characteristics of Fibres,” Textile Industries, 1970; 72: 13-19.

(39)Uniform Language for Testimony and Reports for the Forensic Textile Fiber Discipline,” effective date 

3/1/21. Accessed at https://www.justice.gov/olp/uniform-language-testimony-and-reports on 1/28/2022.

(40)Kidd, C., and Robertson, J., “The transfer of textile fibers during simulated contacts,” Journal of the 

Forensic Science Society, Vol. 3, 1982, pp. 301-308.

(41)Lowrie, C. N., and Jackson, G., "Secondary Transfer of Fibers," Forensic Science International, Vol. 64, 

1994, pp. 73-82.

(42)Pounds, C. A., and Smalldon, K. W., “The transfer of fibres between clothing materials during simulated 

contacts and their persistence during wear. Part I--Fibre transference,” Journal of the Forensic Science 

Society, Vol. 15, 1975, pp. 17-27. 

(43)Robertson, J., and Roux, C., “Transfer, Persistence and Recovery of Fibers.” In Robertson, J., Roux, C., and 

Wiggins K. G. (Eds.), Forensic Examination of Fibres, 3rd edition, Boca Raton: CRC Press, 2018, pp. 109-

119.

(44)Pounds, C. A., and Smalldon, K. W., “The Transfer of Fibres between Clothing Materials During 

Simulated Contacts and their Persistence During Wear: Part II—Fibre Persistence,” Journal of the Forensic 

Science Society, Vol. 15, No. 1, 1975, pp. 29-37.

(45)Pounds, C. A., and Smalldon, K. W., "The transfer of fibres between clothing materials during simulated 

contacts and their persistence during wear. Part III: A preliminary investigation of the mechanisms 

involved,” Journal of the Forensic Science Society, Vol. 15, 1975, pp. 197–207.

(46)Robertson, J., Kidd, C. B. M., and Parkinson, H. M. P., “The persistence of textile fibres transferred during 

simulated contacts,” Journal of the Forensic Science Society, Vol. 22, 1982, pp. 353-360.

(47)Roux, C., Robertson, J., and Palmer, R., “Persistence and Recovery.” In Saukko, P. J., and Houck, M. M. 

(Eds.), Encyclopedia of Forensic Sciences, 2nd edition, Waltham: Academic Press, 2013, pp. 117-123.

(48)Aitken C. G., Taroni F., and Bozza S. Statistics and the Evaluation of Evidence for Forensic Scientists, 3rd 

edition. Chichester, England: John Wiley and Sons, 2021.

(49)Trejos T, Koch S, and Mehltretter A, “Scientific foundations and current state of trace evidence—a review,” 

Forensic Chemistry, 2020: 100223.

(50)Kassin, S. M., Dror, I. E., and Kukucka, J., “The Forensic Confirmation Bias: Problem, Perspectives, and 

Proposed Solutions,” Journal of the Applied Research in Memory and Cognition, Vol. 2, No. 1, 2013, pp. 

42-52.

(51)National Commission on Forensic Science, “Ensuring That Forensic Analysis Is Based Upon TaskRelevant Information,” National Institute of Standards and Technology (NIST), December 8, 2015.

(52)Grieve, M., Roux, C., Wiggins, K.G., Champod, C., and Taroni, F., “Quality Assurance, Report Writing 

and Examples of Casework Findings.” In Robertson, J., Roux, C., and Wiggins, K. (Eds.), Forensic 

Examination of Fibres 3rd Edition, Boca Raton: CRC Press, 2018, pp. 361-370.