Lab: Forensic Analysis of Fibers

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Textiles Natural and Synthetic Fibers Adapted from UEN.org.

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Presentation transcript:

Lab: Forensic Analysis of Fibers Microscopic Observations Burn Test

Burn Test Fiber Microscopic Observation Behavior Nearing Flame Behavior In Flame Behavior Removed From Flame Odor Ash or Residue Acrylic Cotton Nylon Polyester Rayon Silk Wool Unknown

Microscopic Observations

Burn Test Do the fibers melt and/or burn? Do the fibers shrink from the flame? What type of odor do the fumes have? What is the characteristic of any smoke? What does the residue of the burned fibers look like?

Conclusion Based on your microscopic observations and the results of the burn tests, what is the unknown fabric? Which observations do you think are the most helpful in determining the fabric identity? What are the differences between the natural and synthetic fibers?