1. Fiber Transfer Activity

2. Rub your sleeve against your neighbor’s sleeve. Then answer the following questions: Can fibers from one sleeve be detected on the other? Can fibers from one sleeve be detected on the other? Do hand lenses or masking tape aid the investigation? How? Do hand lenses or masking tape aid the investigation? How?

3. Fiber Analysis

4. Introduction to Fibers Trace evidence Trace evidence Class evidence Class evidence Direct transfer: suspect  victim Direct transfer: suspect  victim Secondary transfer: source  suspect  victim Secondary transfer: source  suspect  victim 95% of fibers lost from crime scene within 24 hours 95% of fibers lost from crime scene within 24 hours

5. Forensic scientist determines: Type of fiber Type of fiber Color Color How many of each kind How many of each kind Textile origin Textile origin Multiple Fibers Multiple Fibers Transfers Transfers Type of crime Type of crime

6. Fiber Evidence Collected by: Special vacuums (large areas) Special vacuums (large areas) Sticky tape Sticky tape Forceps Forceps Tested by: Microscopy – polarizing light, infrared Microscopy – polarizing light, infrared Burn test (large quantities only) Burn test (large quantities only)

7. Fibers are spun into yarns that have specific characteristics Fibers are spun into yarns that have specific characteristics Yarns are woven, with different patterns, into textiles Yarns are woven, with different patterns, into textiles Fibers may be natural or synthetic Fibers may be natural or synthetic

8. Fiber Classification (Use textbook p. 81-84) Natural Fibers: (List the different types and examples of each) Synthetic Fibers: (List the different types and examples of each)

9. Natural Fibers Animal fibers (protein) Animal fibers (protein) Sheep – wool Sheep – wool Goats – cashmere, mohair Goats – cashmere, mohair Rabbits – angora Rabbits – angora Caterpillar – silk Caterpillar – silk Plant fibers (cellulose) Plant fibers (cellulose) Seed: cotton Seed: cotton Fruit: coir (coconut) Fruit: coir (coconut) Stem: hemp (Cannabis), jute, flax (linen) Stem: hemp (Cannabis), jute, flax (linen) Leaf: manila, sisal Leaf: manila, sisal Mineral fibers Mineral fibers Fiberglass (glass), asbestos (rock mineral) Fiberglass (glass), asbestos (rock mineral)

10. WOOL COTTON FIBERGLASS

11. ASBESTOS FLAX JUTE

12. HEMP SILK

13. Synthetic (Man-made) Fibers Regenerated fibers (modified natural fibers) Regenerated fibers (modified natural fibers) Rayon Rayon Celanese Celanese Capron Capron Synthetic polymer fibers Synthetic polymer fibers Polyester Polyester Nylon Nylon Acrylic Acrylic Olefins Olefins