Hair analysis

General characteristics of Human Hair

1Colour:White, blonde, light brown, gray brown, dark brown, gray, black, auburn, red.
2Reflectivity:Opaque, gray, translucent, transparent, auburn, clear.
3Length:Fragment, 1”, 1-3”, 3-5”, 5-8”, 8-12”, 12-18”, 18-30”, segment.
4Diameter:20-30 um, 30-40 um, 40-50 um, 50-60 um, 60-70 um, 70-80 um, 80-90 um, 90-100 um, 100-110 um.
5Spatial Configuration:Undulating, kinky, curly, wavy, curved, straight, sinuous
6Tip:Singed, uncut, tapered, rounded, sharp cut, cut at angle, frayed, split, crushed, broken.
7Base:Cut, damaged, pigmented, clear, enlarged, tapering, broken.
8Root:Stretched, absent, bulbous, sheathed, atrophied, follicular, wrenched.
9Cross-section:Polygonal, oval, round oval, undulating, round.
10Pigment:Absent, non-granular, granular, multicolour, chain, massive (clumped), dense, streaked, opaque.
11Medulla:Absent, sparse, scanty, fractional, broken, globular continuous, irregular, double, cellular.
12Cortical fusi:Absent, few, abundant, bunched, linear, central, periphery, roots.
13Cortical cells:Brittle, damaged, fibrous, cellular, invisible, fusiform, ovoid bodies.
14Cosmetic Treatment:Bleached, rinsed, natural, dyed, damaged.
15Cuticle:Ragged, serrated, looped, narrow, layered, wide, cracked, absent, clear, dyed.
16Scales:Flattened, smooth, level, arched, prominent, and serrated.

 Morphological Characteristics of Human Hair for Racial Determination

RaceDiameterCross-sectionPigmentationCuticleUndulation
Negroid60 – 90 umFlatDense & clumpedPrevalent
Caucasoid70 – 100 umOvalEvenly distributedMediumUncommon
Mongoloid90 – 120 umRoundDense AuburnThickNever

 General characteristics of Human Hair from Different Sites

ScalpHead hair, 100 – 1000 mm long, 25-125 um diameter, 0.4 mm/day growth; small root, tapered tip, little diameter variation, various medullation, often with cut tips, may artificially treated.
PubicPudental, 10 – 60 mm long, coarse diameter and prominent diameter, variation and buckling, broad medulla, follicular tags common, asymmetrical cross section twisted and constricted, may be straight, curved or spirally tufted.  
VulvarSecondary pubic hair, finer and shorter than pubic hair, may be abraided.  
ChestPectoral, moderate to considerable diameter variation, long fine arch-like tip, usually longer than pubic hair.
BeardFacial hair, very coarse, 50-300 mm long, large root, irregular structure, often triangular cross section, complex medullation, blunted or razor cut tips, grows 0.4 mm/day.  
AxillaryArm pit, 10-50 mm long, grows 0.3 mm/day, coarse, blunt tip, abraided or frayed, usually straighter than pubic hair, many cortical fusi, sometimes yellowed and bleached.
EyebrowSuperciliary, 1 cm long, 0.16 mm/day growth, curved, relatively coarse for length, smooth curve with punctate tip and large medulla.  
EyelashCiliary, less than 1 cm long, short curved pointed hair.  
LimbLeg and arm hair, 3-6 mm long, fine tips, irregularly medullated, often indistinctly, slightly pigmented.  
EarTragi, pinnae, down  
ButtocksAnal hair, short blunted and abraided hair.  
NoseSimilar to facial hair.  

General Differences between Human Hair and Animal Hair

FeatureHuman HairAnimal Hair
ColourRelatively consistent along shaftOften showing profound colour changes and banding
CortexOccupying most of the width of shaft greater than medullaUsually less than width of medulla
Distribution of pigmentEven, slightly more towards cuticleCentral or denser towards medulla
MedullaLess than one-third width of shaft. Amorphous, mostly not continuous when presentGreater than one-third width of shaft. Continuous, often varying in appearance along shaft, defined structure
ScalesImbricate, similar along shaft from root to tipOften showing variation in structure along shaft from root to tip
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