ASTM E3175-23

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: E3175 − 23 An American National Standard
Standard Practice for
Training in the Forensic Examination of Hair by Microscopy
This standard is issued under the fixed designation E3175; 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 E620 Practice for Reporting Opinions of Scientific or Tech-
nical Experts
1.1 This practice covers training guidelines for use by
E1459 Guide for Physical Evidence Labeling and Related
forensic laboratory personnel responsible for training forensic
Documentation
examiners that will perform hair examinations, including
E1492 Practice for Receiving, Documenting, Storing, and
microscopical comparisons of human hair.
Retrieving Evidence in a Forensic Science Laboratory
1.2 Forensic hair examiners are trained in accordance with
E1732 Terminology Relating to Forensic Science
Practice E2917 and the discipline-specific guidelines (Guide
E2917 Practice for Forensic Science Practitioner Training,
E3316) and criteria within this practice.
Continuing Education, and Professional Development
Programs
1.3 This practice contains guidelines that include the tasks,
goals, and objectives that allow the trainee to acquire the E3316 Guide for Forensic Examination of Hair by Micros-
copy
requisite knowledge, skills, and abilities to independently
perform casework in the microscopical examination of hair.
3. Terminology
1.4 This practice addresses the correlation between the
analytical results of microscopical examinations and the po-
3.1 Definitions—For definitions of terms used in this
tential for DNA analysis.
practice, refer to Terminology E1732.
1.5 This practice addresses training for the microscopical
3.2 Definitions of Terms Specific to This Standard:
examination of hairs and not the examination of chemical
3.2.1 anagen, n—the active growth phase of a hair follicle in
alterations (for example, hair dye) or trace materials on the
the hair growth cycle.
surface of hairs (for example, hair care products).
3.2.1.1 Discussion—The root from a pulled anagen hair is
1.6 This standard does not purport to address all of the
elongated and is usually fully pigmented.
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.
1.7 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
no longer acceptable in the field of anthropology (the field from
Development of International Standards, Guides and Recom-
which these designations originated).
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
2. Referenced Documents
questioned hair are present in the known hair sample without
2 any exclusionary differences and, therefore, the donor of the
2.1 ASTM Standards:
known sample can be included as a possible source of the
questioned hair.
3.2.3.1 Discussion—A microscopical association of hair
This practice is under the jurisdiction of ASTM Committee E30 on Forensic
Sciences and is the direct responsibility of Subcommittee E30.01 on Criminalistics.
cannot identify the definitive source of a questioned hair to the
Current edition approved Oct. 1, 2023. Published October 2023. Originally
exclusion of all others and the number of individuals who
approved in 2022. Last previous edition approved in 2022 as E3175 – 22. DOI:
could be included as a possible donor of a specific hair is
10.1520/E3175-23.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or unknown and cannot be reliably estimated.
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
3.2.4 buckling, n—an abrupt change in the shape and
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. orientation of a hair shaft with or without a slight twist.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E3175 − 23
3.2.5 catagen, n—the transitional phase of the hair follicle 3.2.18 exclusion with limitations, n—the result of a com-
between the active growth phase (anagen) and the resting phase parison between two hair samples in which the characteristics
(telogen) in the hair growth cycle. of the questioned hair differ from those present in the known
hair sample, and therefore the donor of the known sample
3.2.6 classification, n—the systematic arrangement of hairs
cannot be included as a possible source of the questioned hair.
into categories (for example, human, animal, somatic origin,
3.2.18.1 Discussion—This result is reached in a compara-
ancestry) based on shared traits.
tive hair examination when differences are noted in the
3.2.7 cortex, n—the primary anatomical region of a hair
macroscopic or microscopic characteristics between the ques-
between the cuticle region and the medullary region composed
tioned and known hairs; however, the differences are insuffi-
of elongated and fusiform cells.
cient for an absolute exclusion of a person as a possible source.
3.2.8 cortical fusi, n—small air spaces that form between
This could be due to the natural variation that occurs in hairs
the cortical cells in the hair shaft and, under transmitted light,
as a biological specimen, the effect that time or environment
appear as tiny, dark structures.
can have upon a hair, or the reference sample does not capture
the complete variation of the individual’s hair.
3.2.9 cortical texture, n—the relief or definition of the
margins of the cortical cells when viewed using transmitted
3.2.19 exclusionary difference, n—a difference in a feature
light microscopy.
or property between compared items that is substantial enough
3.2.10 cross-sectional shape, n—the shape of a hair shaft to determine that they did not originate from the same source.
when cut at a right angle to its longitudinal axis.
3.2.20 fungal tunneling, n—air pockets in a hair shaft
3.2.10.1 Discussion—When viewed longitudinally with
caused by fungal growth.
transmitted light, the apparent cross-sectional shape is deter-
3.2.21 hair, n—a fibrous outgrowth from the skin of mam-
mined by slowly focusing through the hair (optical cross-
mals.
sectioning). When viewed longitudinally between crossed
polars, the cross-sectional shape can be determined by observ-
3.2.22 hair follicle, n—an invagination of the epidermis
ing the interference colors.
which contains the root of the hair.
3.2.11 cuticle, n—the outermost region of a hair composed
3.2.23 imbricate, n—a term that describes a scale pattern in
of layers of overlapping scales.
which the scales overlap and the edges have an irregular wavy
3.2.11.1 Discussion—The dimension of the cuticle as mea-
pattern. This pattern is typical of human hair.
sured from its outer margin to the cortex is often described in
3.2.24 inconclusive, n—the result of a comparison between
relative terms (for example, thin, medium, thick).
two hair samples in which similarities and differences were
3.2.12 cuticle, cracked, n—a cuticle with linear breaks that
observed in the characteristics of the provided standard and the
are perpendicular to the length of the shaft.
questioned hair to the extent that the known source of the
3.2.13 cuticle, looped, n—a feature in which the distal edges
standard could not be included or excluded as a possible source
of the cuticular scales are curved away from or cupped toward
of the questioned hair.
the hair shaft.
3.2.25 individualization, n—a term indicating an individual
3.2.14 cuticle, serrated, n—a cuticle in which the outer
can be discriminated to the exclusion of all other sources.
margin has a notched appearance like a saw blade.
3.2.25.1 Discussion—Hairs cannot be individualized via
3.2.15 decompositional changes, n—alteration in the root or
microscopical hair comparison.
the proximal end of a hair that can include discoloration,
3.2.26 inner cuticle margin, n—the border between the
postmortem root banding, or a tapered or brush-like
cortex and the visible cuticle.
appearance, as well as fungal tunneling along the length of the
3.2.27 keratin, n—a class of sulfur-containing fibrous pro-
shaft.
teins that forms the foundation of outgrowth tissue from the
3.2.16 distal end, n—the end of the hair farthest away from
epidermis, such as hair, nails, feathers, and horns.
the root.
3.2.28 macroscopic, n—a term that describes characteristics
3.2.17 exclusion/elimination, n—the result of a comparison
large enough to be perceived without magnification.
between two hair samples in which exclusionary differences
are observed in the characteristics of the questioned hair that 3.2.29 medulla, n—the core of the hair shaft that is com-
are not present in the known hair sample, and therefore the
posed of vacuoles and cells that can be air- or fluid-filled.
donor of the known sample can be excluded as a possible
3.2.29.1 Discussion—The medulla (if present) occurs in a
source of the questioned hair.
continuous, discontinuous, or fragmented pattern along the
3.2.17.1 Discussion—This result is reached in a compara-
length of a hair and appears translucent or opaque.
tive hair examination when exclusionary differences (for
3.2.30 microscopic, n—a term that describes characteristics
example, color, characteristics indicative of ancestry) are noted
too small to be resolved by the unaided eye, but large enough
in the macroscopic or microscopic characteristics between the
to be resolved with a microscope.
questioned and known hairs. In these circumstances, the source
of the known hairs, as represented by the known sample, is 3.2.31 microscopical, n—concerning a microscope or the
eliminated as a possible source of the questioned hair. use of a microscope.
E3175 − 23
3.2.32 monilethrix, n—a hair disorder that results in periodic 3.2.48 shaft form, n—the shape of the hair both longitudi-
nodes or beading along the length of the hair with intervening, nally (for example, curly, straight) and cross-sectionally (for
tapering constrictions that are not medullated. example, round, flattened).
3.2.49 shaft thickness, n—the diameter of the hair.
3.2.33 ovoid bodies, n—oval-shaped, heavily-pigmented in-
3.2.49.1 Discussion—This is expressed either numerically
clusions usually found in the hair cortex.
or in relative terms, such as fine, medium, or coarse.
3.2.34 pigment aggregation, n—clusters of pigment gran-
3.2.50 shouldering, n—a variation of the hair form along the
ules.
shaft, resulting in an irregular and often asymmetrical change
3.2.35 pigment density, n—the relative abundance of pig-
of cross-sectional shape.
ment granules in the hair cortex as described along a con-
3.2.51 somatic region, n—an area of the body, such as head,
tinuum (for example, sparse, medium, heavy).
pubic, or leg; synonymous with “body area”.
3.2.36 pigment distribution, n—the pattern or arrangement
3.2.52 telogen, n—the resting phase of the hair follicle in the
of the pigment granules in the hair shaft, such as uniform,
hair growth cycle.
peripheral, one-sided, variable, or central.
3.2.52.1 Discussion—During this phase, the hair has
stopped growing and the root becomes keratinized and bulbous
3.2.37 pigment granules, n—small particles in hair com-
(club-like) in shape.
posed of melanin that impart color.
3.2.37.1 Discussion—Melanin is a natural pigment of which 3.2.53 tip, n—the most distal end of a hair shaft.
two forms, eumelanin (brown to black) and phaeomelanin
4. Significance and Use
(reddish brown to yellow), determine the color of human and
animal hair.
4.1 A training program provides the theoretical foundation
and practical skills necessary for a trainee to become a
3.2.38 pili annulati, n—a hair disorder causing hairs to
qualified forensic hair examiner.
appear ringed or banded due to the alternating light and dark
bands in the hair shaft. The dark bands are a manifestation of
4.2 A trainee is directly supervised by a qualified examiner
abnormal air spaces in the cortex.
throughout their training. At the end of the training program, a
successful trainee is capable of forming opinions, presenting
3.2.39 pili torti, n—a hair disorder characterized by the hair
and explaining evidence, and understanding the limitations of
shaft being flattened and twisted 180 degrees numerous times
analytical results and interpretations based upon sound scien-
along its axis. It is usually found at irregular intervals along the
tific knowledge, validated procedures, and practical experi-
shaft.
ence.
3.2.40 postmortem root banding, n—the appearance of an
4.3 A trainee is required to meet the minimum training
opaque band near the root/proximal end of a hair potentially
criteria in Practice E2917 and this practice. It is the laboratory
observed in anagen or catagen hairs that have been removed
management’s responsibility to ensure the selected trainee has
from a decomposing body. The possibility of other conditions
the appropriate educational background. It is recommended
causing the same or similar characteristics cannot be elimi-
that, at a minimum, the trainee possess a bachelor’s degree in
nated.
a natural science.
3.2.41 proximal end, n—the portion of the hair closest to,
4.4 This document outlines lessons, practical exercises, and
and including, the root.
criteria to monitor and evaluate trainee progress and is de-
3.2.42 root, n—the structure that anchors a hair to a follicle signed to be incorporated into an overall laboratory training
and from which cells divide and produce the hair shaft.
program.
3.2.42.1 Discussion—The portion of follicular tissue sur-
4.5 Additional training beyond that which is listed here
rounding a root structure is the sheath.
should be made available to the trainee. Such training might
include off-site courses, internships, and specialized training by
3.2.43 sample, known, n—a sample for which the identity of
experienced examiners. Continuing education and training will
the donor is established and which is used for comparison
provide a forensic examiner the opportunity to remain current
purposes.
in the field.
3.2.44 sample, limited, n—a sample of known hairs that is
4.6 Additional analyses can be performed on hairs that have
insufficient in quality or quantity to reflect a representative
been chemically altered (for example, dyed hair) or have trace
range of characteristics or traits.
materials on the surface (for example, glitter). Such techniques
3.2.45 sample, representative, n—a collection of hairs from
are beyond the scope of this document.
a specific somatic region that reflects the range of characteris-
4.7 This practice addresses the benefit of following micro-
tics in a person’s hair in that area.
scopical examinations with DNA analysis.
3.2.46 scales, n—overlapping, plate-like structures com-
posed of keratin that form the cuticle.
5. Syllabus
3.2.47 shaft, n—the portion of the hair emerging from the 5.1 A training program syllabus and guidelines should
hair follicle. contain tasks, goals, and objectives that allow the trainee to
E3175 − 23
acquire the requisite knowledge, skills, and abilities to inde- 6. Records of Training
pendently perform casework in the microscopical examination
6.1 The training progress is reviewed, assessed, and docu-
of hair. It should include different types of instruction and
mented by the trainer(s) in accordance with Practice E2917.
learning (for example, classroom-like instruction, practical
6.2 Training documentation is maintained according to
exercises, self-study of relevant literature) with progress con-
Practice E2917.
tinually assessed through oral and written evaluations, includ-
ing pass/fail criteria and provisions for remedial training. This
7. Responsibilities
can be accomplished through a combination of the following
7.1 Each trainee is trained by, and works under the super-
types of training:
vision of, one or more experienced forensic hair examiners.
5.1.1 Reading of relevant literature.
7.2 Only technically-competent personnel are designated
5.1.2 Instruction and observation of hair examiners:
trainers; this would include expertise in the areas of micro-
5.1.2.1 Lectures and discussions,
scopical hair examination, hair comparison, or evaluation of
5.1.2.2 Practical demonstration of basic skills,
hairs for DNA suitability. These trainers are responsible for:
5.1.2.3 Supervised casework, and
7.2.1 Introducing the trainee to the relevant scientific
5.1.2.4 Monitored court testimony.
literature, validated procedures, training material, and refer-
5.1.3 Practical skills:
ence collections,
5.1.3.1 Practical exercises, and
7.2.2 Discussing readings and theory with the trainee,
5.1.3.2 Assisting in and performing supervised casework.
7.2.3 Teaching basic microscopy methods and techniques
5.1.4 Examinations and tests:
for hair microstructure comparison,
5.1.4.1 Written or oral tests,
7.2.4 Teaching case management,
5.1.4.2 Practical laboratory tests, and 7.2.5 Fostering ethical and professional conduct through
discussion and by setting an example,
5.1.4.3 Mock/moot court.
7.2.6 Teaching quality assurance and quality control
5.1.5 Competency evaluation in accordance with Practice
procedures,
E2917.
7.2.7 Reviewing tests, practical exercises, and casework
5.2 This is an extensive training program and it is expected
samples with the trainee, and
that it will take approximately six months to one year to
7.2.8 Teaching expert testimony skills through moot court,
complete.
observation of testimony, or both.
5.2.1 Required topics include:
7.3 The trainer and supervisor regularly monitor the train-
5.2.1.1 Occurrence, transfer, and persistence of hairs,
ee’s progress with frequent updates.
5.2.1.2 Evidence recovery methods,
7.4 The trainee completes the objectives set forth in the
5.2.1.3 Evidence handling to minimize contamination and
training program by:
loss,
7.4.1 Self-study of reading materials,
5.2.1.4 Evidence packaging and documentation,
7.4.2 Practicing basic microscopy skills,
5.2.1.5 Use and maintenance of microscopes,
7.4.3 Successfully completing practical exercises,
5.2.1.6 Understanding of hair chemistry, biology, structure,
7.4.4 Successfully completing written or oral tests, or both,
and function,
7.4.5 Observing casework being conducted by an experi-
5.2.1.7 Recognition of roots in different growth stages,
enced examiner,
5.2.1.8 Recognition of diseases manifested in hairs (for
7.4.6 Observing court testimony given by an experienced
example, monilethrix, pili annulati, pili torti),
examiner or reviewing transcripts where hair evidence was
5.2.1.9 Recognition of characteristics indicative of me-
presented, or both,
chanical damage (for example, looped or serrated cuticle),
7.4.7 Conducting themselves in an ethical and professional
environmental effects, decomposition (for example, postmor-
manner,
tem root band), and chemical treatments (for example, cortical
7.4.8 Participating in the quality assurance and quality
texture, dye lines),
control program of their laboratory,
5.2.1.10 Identification and classification of hairs,
7.4.9 Successfully completing competency tests in
5.2.1.11 Comparison of questioned and known hairs,
identification, comparison, or evaluation for DNA suitability,
5.2.1.12 Other analytical techniques (DNA),
and
5.2.1.13 Interpretation of comparison results, including 7.4.10 Demonstrating competency in supervised casework.
limitations,
7.5 Each laboratory is responsible for maintaining:
5.2.1.14 Preparation of laboratory reports, and
7.5.1 An up-to-date training program, and
5.2.1.15 Presentation and interpretation of analytical results
7.5.2 Documentation of training, including competency
in court.
tests.
5.2.2 A trainee with experience in other areas of forensic
8. Training Program Requirements
science who has knowledge in microscopy, in other areas of
trace evidence, or in court testimony would not require such an 8.1 The following sections outline the minimum require-
extensive training regimen. ments for a training program by topic area. A laboratory may
E3175 − 23
modify the training program to correspond with specific areas each observation, the trainee and the examiner should discuss
of hair examination performed in their laboratory. the courtroom experience and, if possible, review the tran-
script.
8.1.1 Each topic area is divided into sections that include
8.1.10 Court testimony training includes a moot court exer-
general discussions of the subject in that particular topic area;
cise. The trainee’s moot court is challenging and mimics as
the skill to be gained by learning that particular subject; the
closely as possible a real courtroom experience. The trainee is
relevant readings; practical applications of the knowledge
evaluated on appearance, demeanor, knowledge of the case,
gained; and, when appropriate, testing of the trainee’s knowl-
knowledge of the discipline, scientific accuracy, impartiality,
edge and skills.
and presentation skills.
8.1.2 Reading assignments are selected to give the trainee a
8.1.11 The trainee’s progress is continually monitored ac-
sound theoretical background and solid foundation in topics
cording to objective criteria established by the laboratory.
necessary for hair examination. The listed publications can be
Periodic progress assessments involving the trainee, trainer,
supplemented by additional readings.
and supervisor should be conducted. Deficiencies in the train-
8.1.3 Essential skills are demonstrated by the trainer and
ee’s performance are addressed immediately. Remediation
practiced by the trainee.
should be made available through additional training and a
8.1.4 Practical exercises are designed to provide the trainee
re-evaluation of the training program.
the skills necessary to perform casework. The trainer observes
8.1.12 Continued deficiencies could suggest the unsuitabil-
the trainee’s performance during the exercises and evaluates
ity of the trainee for casework in this area.
the trainee’s ability to conduct microscopical examinations.
The trainer will document the assessment and make a deter- 8.2 Training Course Evaluation:
mination about the need for additional training. Satisfactory 8.2.1 Evaluate the training program to assess its efficacy and
completion of the exercises is documented. relevance as described in Practice E2917.
8.2.2 The trainee should be given a chance to evaluate the
8.1.5 To assess the trainee’s comprehension of the materials,
hair training program and the trainer. Perceived deficiencies in
use a combination of written, oral, and practical laboratory
the training program or the trainer should be addressed.
tests. The trainer should address deficiencies through addi-
tional training.
8.3 Authorization for Casework:
8.1.6 The trainee observes an experienced hair examiner
8.3.1 Upon successful completion of the training program
perform all aspects of casework. This helps the trainee under-
and a comprehensive competency test, the trainee will receive
stand the various aspects of casework including record keep-
written approval from designated laboratory personnel (for
ing; processing of evidence; sample preparation; microscopical
example, quality control officer, training manager) to perform
study of prepared specimens; and the characterization,
supervised casework.
identification, comparison, and interpretation (including the
8.3.2 After successful completion of supervised casework,
limitations) of hair evidence. During the observation of
the trainee will receive written approval from designated
casework, the experienced examiner provides instruction to the
laboratory personnel (for example, quality control officer,
trainee while performing all examinations and comparisons.
training manager) to perform independent casework in micro-
The examiner also demonstrates the documentation of obser-
scopical hair examinations.
vations and reporting of analytical results and interpretations.
8.1.7 A competency test is administered prior to the trainee
9. Casework Familiarization, Search, and Recovery of
analyzing and comparing hair evidence in supervised case-
Hair Evidence
work.
9.1 This section familiarizes the trainee with the documen-
8.1.7.1 Discussion—The test should be designed to mimic
tation needed in casework and the methods of detection,
actual casework, requiring the trainee to demonstrate knowl-
collection, and preservation of trace evidence from crime
edge of the laboratory’s procedures in handling evidence,
scenes and from items submitted to the laboratory. This
taking notes, maintaining chain of custody, and writing a
training exposes the trainee to evidence handling issues such as
report, as well as the actual examination and comparisons of
deposition, transfer, persistence, contamination, and loss of
hair evidence. It is the responsibility of the laboratory man-
trace evidence.
agement to establish written objective criteria for successfully
9.2 Expose the trainee to a variety of cases involving hair
passing the competency test. Deficiencies or failures, if any, are
examinations throughout the training period.
noted, a remediation plan developed, and a subsequent com-
petency exam given until the trainee meets the criteria for
9.3 Required Training Topics Include:
successfully passing the competency exam.
9.3.1 Procedures for case documentation,
8.1.8 Prior to independent casework, the trainee performs 9.3.2 Recognition of hair and other evidentiary materials
supervised casework. The trainer or case supervisor verifies all
and the evaluation of their significance in a particular case,
laboratory results obtained by the trainee and documents that 9.3.3 Detection, collection, and preservation techniques ap-
verification during supervised casework.
propriate to the different types of forensic evidence, including
hairs,
8.1.9 The trainee should observe experienced examiners
testifying in court. The trainee should pay attention to general 9.3.4 Loss, transfer, and persistence of trace evidence,
courtroom procedures, the witness’s appearance and demeanor, 9.3.5 Prevention of contamination and loss in handling hair
and the presentation of technical or expert knowledge. After evidence,
E3175 − 23
9.3.6 Laboratory procedures for maintaining the chain of 9.5.3.10 Health and safety hazards, and
custody of the original evidence and secondary evidence
9.5.3.11 Laboratory quality assurance procedures.
collected,
9.6 Practical Exercises:
9.3.7 Safety procedures in the laboratory for the handling of
9.6.1 Practice collecting hair from a variety of items (for
potentially biohazardous materials, and
example, clothing, tape, items of various sizes and surface
9.3.8 Documentation of analytical results, as required by the
textures, weapons). Skills practiced should include:
trainee’s laboratory.
9.6.1.1 Different techniques of recovery (for example,
9.4 Review relevant historical and current literature in the
scraping, tape lifting, vacuuming, picking),
fields of anthropology, dermatology, cosmetology, develop-
9.6.1.2 Packaging and preserving evidence, and
mental biology, and forensic science related to hair examina-
9.6.1.3 Collection of known or reference materials on mock
tions.
evidence.
9.4.1 Recommended Reading Assignments:
9.7 Supervised Casework:
(1) ASTM Standards:
9.7.1 Under the direct supervision of the trainer, the trainee
(a) E1459, Guide for Physical Evidence Labeling and
is assigned select cases to process for the purposes of recov-
Related Documentation
ering and safeguarding trace materials. The trainee will use the
(b) E1492, Practice for Receiving, Documenting, Storing,
procedures and techniques learned to process and document the
and Retrieving Evidence in a Forensic Science Laboratory
evidence.
(2) Bisbing, R., “The Forensic Identification and Associa-
tion of Human Hair,” In: Saferstein, R. (Ed.), The Forensic
9.8 Examinations and Tests:
nd
Science Handbook, Vol 1, 2 edition, Upper Saddle River,
9.8.1 Written, oral, or practical laboratory tests, or any
New Jersey: Pearson Education, 2002, pp. 390-428.
combination thereof, are given to the trainee to evaluate the
(3) Inman, K., and Rudin, N., Principles and Practice of
acquired knowledge and skills covered in each part of training.
Criminalistics, the Profession of Forensic Science (Chapters 4,
9.9 Competency Evaluation:
5, 9, and 10), Boca Raton: CRC Press, 2001.
9.9.1 Evaluate the trainee’s ability to choose and perform an
(4) Oien, C.T., “Forensic Hair Comparison: Background
appropriate evidence recovery technique.
Information for Interpretation,” Forensic Science
9.9.2 Evaluate the trainee’s knowledge of laboratory proce-
Communications, Vol 11, No. 2, 2009.
dures for creating a case file, handling evidence safely, and
(5) Robertson, J., “Forensic and Microscopic Examination
labeling evidence.
of Human Hair.” In: J. Robertson (Ed.), Forensic Examination
of Hair, London: Taylor and Francis, 1999, pp. 79-155.
10. Microscopy
(6) Robertson, J., and Roux, C., “From the Crime Scene to
the Laboratory– Transfer, Persistence and Recovery of Fibres,”
10.1 This section familiarizes the trainee with the theory,
In: Robertson, J. and Grieve, M. (Eds.), Forensic Examination
basic procedures, and techniques for the operation of a
nd
of Fibres, 2 edition, London: Taylor and Francis, 1999, pp.
stereomicroscope, compound microscope, and comparison mi-
89-100.
croscope. The care and maintenance of these microscopes
(7) Springer F., “From the Crime Scene to the Laboratory
should also be discussed.
– Collection of Fibre Evidence from Crime Scenes,” In:
10.2 Required Training Topics Include:
Robertson, J. and Grieve, M. (Eds.), Forensic Examination of
nd
10.2.1 Why different types of microscopes are used in hair
Fibres, 2 edition, London: Taylor and Francis, 1999, pp.
examination,
101-115.
10.2.2 How microscopes work (theory),
9.5 Instruction and Observation:
10.2.3 The operation and maintenance of the different types
9.5.1 Observe hair casework, from the assignment of a case
of microscopes,
through an examination, to the preparation of a report.
10.2.4 Setting up Köhler (or modified Köhler) illumination,
9.5.2 Discuss all aspects of casework, having the trainer
and
explain each step as the case is processed.
10.2.5 The selection of mounting media.
9.5.3 Instruction will be given in the following topics:
9.5.3.1 Documentation required for a case file,
10.3 Recommended Reading Assignments:
9.5.3.2 Description and labeling of evidence, (1) Operation manuals for the microscopes used by the
9.5.3.3 Procedures required to maintain chain of custody,
trainee.
9.5.3.4 Procedures to prevent contamination and loss, (2) Collins, T., “Mounting Media and Antifade Reagents,”
9.5.3.5 Procedures to clean and control the laboratory
Microscopy Today, Vol 14, No. 1, 2006, pp. 34-39.
environment, (3) De Forest, P.R., “Foundations of Forensic Microscopy.”
nd
9.5.3.6 Selection of the appropriate detection, collection,
In: Saferstein, R. (Ed.), The Forensic Science Handbook, 2
and preservation techniques for hair and other trace evidence, edition, Upper Saddle River, New Jersey: Pearson Education,
9.5.3.7 Recognition of evidence as questioned specimens or
2002, pp 215-320.
known samples, (4) Greenwell, M.D., Willner, A., and Kirk, P., “Human
9.5.3.8 Collection of representative known samples,
Hair Studies: III. Refractive Index of Crown Hair,” J Criminal
9.5.3.9 General laboratory protocols, Law and Criminology, Vol 31, No. 6, 1941, pp. 746-752.
E3175 − 23
(5) Neuhaus, B., and Schmid, T, “Collection Management 11. Introduction to Hairs – Human and Animal Hairs
and Study of Microscope Slides: Storage, Profiling,
11.1 This section familiarizes the trainee with the funda-
Deterioration, Restoration Procedures and General
mental biology, physiology, and anatomy of hair, as well as the
Recommendations,” Zootaxa, Vol 4322, No. 1, 2017, pp.1-173.
history of hair examination, its limitations, and definitions of
(6) Roe, G.M., Cook, R., and North, C., “An Evaluation of
terms used in hair classification and comparison.
Mountants For Use in Forensic Hair Examination,” Journal of
11.2 Required Training Topics Include:
the Forensic Science Society, Vol 31, No. 1, 1991, pp. 59-65.
(7) Shamala, R., and Surekha, R., “Mounting Media: An 11.2.1 The purpose and function of human and animal hair,
Overview,” Journal of Dr. NTR University of Health Sciences,
11.2.2 The structures of human and animal hair,
Vol 3, No. 5, 2014, pp.1-8.
11.2.3 The growth of human hair,
10.4 Practical Exercises: 11.2.4 The chemical composition of hair,
10.4.1 Familiarization with the stereomicroscope, com- 11.2.5 The history of hair examination,
pound microscope, and the comparison microscope:
11.2.6 Definitions of terms, and
10.4.1.1 Check the alignment of the condenser, the stage,
11.2.7 Classification of hair.
and the objectives on the compound microscope and the
11.3 Recommended Reading Assignments:
comparison microscope.
(1) Beckert, J., “Forensic Hair Microscopy,” In: Desiderio,
10.4.1.2 Check the color balance on the comparison micro-
V.J., Taylor, C. E., and Daeid N.N. (Eds.), Handbook of Trace
scope. The trainer demonstrates to the trainee how to balance
Evidence Analysis, Hoboken, NJ: John Wiley & Sons Ltd.,
the background color on both sides of the comparison micro-
2021, pp. 219-376.
scope. The trainee should then practice this technique. Refer to
(2) Deedrick, D., and Koch, S., “Microscopy of Hair Part
Guide E3316 for color balancing techniques.
1: A Practical Guide and Manual for Human Hairs,” Forensic
10.4.1.3 Experiment with, and understand the effect of,
Science Communications, Vol 6, No. 1, 2004.
different colored contrast filters and neutral density filters.
(3) Deedrick, D., and Koch, S., “Microscopy of Hair Part
10.4.1.4 Observe how to set up Köhler (or modified Köhler)
2: A Practical Guide and Manual for Animal Hairs,” Forensic
illumination. The trainee should routinely employ this tech-
Science Communications, Vol 6, No. 3, 2004.
nique when using the microscope.
(4) Harding, H., and Rogers, G., "Physiology and Growth
10.4.1.5 Calibrate the eyepiece reticle for all objectives on
of Human Hair," In: Robertson, J. (Ed.), Forensic Examination
the compound microscope and the comparison microscope.
of Hair, London: Taylor and Francis, 1999, pp. 1-77.
(5) Kaszynski, E., “Hair Growth: Mechanism and
10.4.1.6 Evaluate how adjustments made to the microscope
Regulation,” In: The Proceedings of the International Sympo-
(for example, apertures, condenser, focus) affect the appear-
sium on Forensic Hair Comparison, Washington, DC: Federal
ance of the sample.
Bureau of Investigation, U.S. Government Printing Office,
10.4.2 Selection of mounting media:
1985, pp. 23-34. This reference can also be found at https://
10.4.2.1 Mount several hairs using different temporary or
www.ncjrs.gov/pdffiles1/Digitization/116592NCJRS.pdf, ac-
semi-permanent mounting media, or both. Discuss utility,
cessed on December15, 2020.
precautions, and limitations in choosing a mounting medium
(6) Long, B., Walbridge-Jones, S., Lundgren, K., “Syn-
with respect to possible changes to the original evidentiary
thetic Wig Fibers: Analysis & Differentiation from Human
hair.
Hairs,” Journal of the American Society of Trace Evidence
10.4.2.2 Know the refractive index of the mounting media
Examiners, Vol 5-1, 2014, pp. 2-21.
used and compare the relative refractive index of human hair to
(7) Robbins, C. R., “Chemical Composition of Different
each of the media (greater or less than the medium).
Hair Types,” Chemical and Physical Behavior of Human Hair,
10.4.2.3 Experiment with different refractive index media to
New York: Springer-Verlag, 2012, pp. 105-176.
see which produces the best visible detail in different parts of
(8) Robertson, J., “Forensic and Microscopic Examination
the hair.
of Human Hair.” In: J. Robertson (Ed.), Forensic Examination
10.4.3 Evaluation of effective cover slip thickness:
of Hair, London: Taylor and Francis, 1999, pp. 79-155.
10.4.3.1 Mount several hairs using different cover slip
(9) Tridico, S., “Examination, Analysis, and Application of
thicknesses and different mounting media thicknesses. The
Hair in Forensic Science-Animal Hair,” Forensic Science
trainee should experiment with different thicknesses of each to
Review, Vol 17, No. 1, 2005, pp. 17-28.
see which gives the best image in different levels or depths
(10) Trejos, T., Koch, S., and Mehltretter, A., “Scientific
within the preparation.
Foundations and Current State of Trace Evidence—A Review,”
Forensic Chemistry, Vol 18, 2020.
10.5 Competency Evaluation:
10.5.1 Evaluate the trainee’s knowledge and competency to 11.4 Practical Exercises:
operate a microscope with a written quiz or a practical test.
11.4.1 Become familiar with the basic appearance of hair by
10.5.1.1 Test the trainee’s ability to correct a microscope utilizing a stereomicroscope. This can be accomplished by
set-up that is misaligned and maladjusted, including achieving examining several known human and animal hairs, and making
optimal illumination, color, and intensity balance of the light notations regarding the general appearance and characteristics
sources on the microscope(s). that are visible under the lower power magnification.
E3175 − 23
11.4.2 Examine the samples from 10.4.2.1 utilizing a com- 12.3 Recommended Reading Assignments:
pound microscope, noting the greater number of characteristics (1) D’Andrea, F., Fridez, F., and Coquoz R., “Preliminary
visible in the mounted hairs under higher magnification. Experiments on the Transfer of Animal Hair During Simulated
11.4.3 Classify the basic root types: Criminal Behaviour,” Journal of Forensic Sciences, Vol 43,
11.4.3.1 Remove several hairs from a used hair brush and 1998.
classify the roots. (2) Deedrick, D., and Koch, S. “Microscopy of Hair Part 2:
11.4.3.2 Pull several head hairs from your head and one A Practical Guide and Manual for Animal Hairs,” Forensic
other person’s head and classify the roots and whether there is Science Communications, Vol 6, No. 3, 2004.
a follicular tag or tissue suitable for DNA analysis. (3) Deedrick, D., “Hairs, Fibers, Crime and Evidence Part
11.4.3.3 Observe the root shapes of a variety of animal 1: Hair Evidence,” Forensic Science Communications, Vol 2,
hairs. No. 3, 2000.
11.4.4 Using human and animal hairs, identify the cuticle, (4) Moore, T.D., Spence, L.E., and Dugnolle, C.E., Identi-
cortex, medulla, cortical fusi, ovoid bodies, and pigment fication of the Dorsal Guard Hairs of Some Mammals of
granules, when present. Wyoming, Bulletin No. 14. Wyoming Game and Fish Dept.,
11.4.4.1 Observe hairs and learn features of cuticle looping, 1974.
imbricate scale pattern, cortical texture, and pigment patterns (5) Petraco, N., and Kubic, T., Color Atlas and Manual of
(for example, pigment aggregation, pigment density, and pig- Microscopy for Criminalists, Chemists, and Conservators,
ment distribution), fungal tunneling, and shouldering). Boca Raton: CRC Press, 2003, pp. 69-76.
11.4.5 Practice cross-sectioning: (6) Robertson, J., “Forensic and Microscopic Examination
11.4.5.1 Compare to optical cross sectioning. of Human Hair,” In: Robertson, J. (Ed.), Forensic Examination
11.4.5.2 Discuss utility and precautions in using these of Hair, London: Taylor and Francis, 1999, pp. 79-155.
techniques as to possible changes to the original evidentiary (7) Tridico, S., “Examination, Analysis, and Application of
hair. Hair in Forensic Science-Animal Hair,” Forensic Science
11.4.5.3 Discuss the importance and retention of surface Review, Vol 17, No. 1, 2005, pp. 17-28.
debris. (8) Tridico, S., “Hair of the Dog: A Case Study,” In: Houck,
11.4.6 Examine synthetic wig-type fibers and human wig M.M. (Ed.), Trace Evidence Analysis — More Cases in Mute
hairs. Witnesses, Elsevier Academic Press: Amsterdam, 2004, pp.
11.4.7 Practice documenting observations using specific 27–52.
laboratory requirements, concentrating on the characteristics (9) Teerink, B. J., Hair of West European Mammals: Atlas
that enable the trainee to differentiate between human and and Identification Key. Cambridge: Cambridge University
animal hair. Press, 2004.
11.5 Competency Evaluation:
12.4 Observation and Discussion:
11.5.1 Evaluate the trainee’s knowledge and competency in
12.4.1 Examine several types of human and animal hairs
the basic characteristics of hair with a written, oral, or practical
using macroscopical and microscopical techniques to study/
test, or any combination thereof.
evaluate the various characteristics that distinguish animal hair
11.5.1.1 This could include drawing the microscopic fea-
from human hair (for example, different medullary patterns,
tures of a hair and defining the terms.
scales, roots, tips, color, banding, shape, and diameter).
12.4.2 Observe and discuss the various procedures for
12. Animal Hairs – Introduction to the Recognition of
making scale casts.
Animal Hairs
12.5 Practical Exercises:
12.1 This section familiarizes the trainee with the micro-
12.5.1 Mount guard hairs and fur hairs (under hairs) from
scopic characteristics in animal hair, including differentiating
several different animal types. Include, at a minimum, dog, cat,
animal hair from human hair; describing features that aid in the
rabbit, horse, cow, bear, rat, and deer hairs.
determination of animal species, genus, or family; and famil-
12.5.2 Microscopically examine these known animal hairs
iarizing the trainee with available identification schemes for the
classification of animal hair. for medullary structure, scale features, and other microscopic
characteristics, noting how they differ from human hairs, how
12.1.1 This section is intended to be an introduction to the
identification of animal hairs and is not meant to be an in-depth they differ between animal families, and how they differ within
the same animal and within the same hair as well. Practice
training program for the purpose of classifying and comparing
animal hairs. note-taking on the characteristics observed under the micro-
scope.
12.2 The knowledge, training, and experience required for
12.5.3 Make scale casts of the entire length of both guard
the trainee to complete this section include the ability to:
hairs and fur hairs using various techniques. Examine casts and
12.2.1 Recognize animal hairs and hair types (for example,
describe scale patterns, noting the different characteristics.
guard and fur),
12.5.4 Repeat these exercises using hairs that are commonly
12.2.2 Make scale casts and observe scale patterns, and
used for apparel, such as chinchilla, wool, llama, mink, etc.
12.2.3 Identify and characterize the differences in the mi-
croscopic characteristics between animal species, genera, and 12.5.5 Compare all of the above-prepared animal hairs to
families. human hairs derived from different body areas.
E3175 − 23
12.6 Competency Evaluation: Journal of American Academy of Dermatology, Vol 43, No. 5,
12.6.1 Evaluate the trainee’s ability to differentiate human Pt. 1, 2000, pp. 814-820.
hairs from other animal hairs using a set of unknown hair (7) Koch, S.L., Michaud, A.L., and Mikell, C.E., “Tapho-
samples. nomy of Hair – A Study of Postmortem Root Banding,”
Journal of Forensic Sciences, Vol 58, No. s1, 2013, pp.
13. Characterization and Assessment of Human Hairs
S52-S59.
(8) Koch, S.L., Shriver, M.D., and Jablonski, N.G., “Varia-
13.1 This section familiarizes the trainee with the micro-
tion in Human Hair Ultrastructure Among Three Biogeo-
scopic charac
...