Hair/fiber collection techniques

o   http://www.crimeandclues.com/index.php/forensic-science-a-csi/trace-a-dna/19-trace-evidence-hair  



http://www.nij.gov/training/firearms-training/module06/images/fir_m06_t04_01.1.jpg

o   Depending on the circumstance, collection of hair evidence can be performed in numerous ways. The first type of collection for visually observed hairs can be gathered with the investigators hands or with tweezers. When choosing tweezers, however, note that they can cause damage to the hair structure and may hinder DNA analysis by crushing the delicate root structure and surrounding tissue.  The next kind of collection for observable or unobservable hairs utilizes clear tape to lift up the evidence from various surfaces. With this approach, be cautious that fibers from the source do not obstruct your evidence by sticking to the tape. The third technique, vacuuming, is employed in large crimes scenes where major points of transfer are unidentified or on stationary objects that cannot be moved elsewhere.  Another way to gather hair evidence is by brushing, scraping, or shaking the observed material over a white sheet of paper to wear down and remove hair attached to the article. This process would require the separation of detached trace evidence into categories such as hair, fiber, or glass. A similar approach to collect hair evidence would be to place materials in a bag and agitate it. The benefit of this is that all evidence is completely caught in the bag. The last method of collection is accomplished by combing or clipping any loose hairs from either a suspect or a victim. A sufficient amount of scalp hair is roughly 100 hairs and 30 to 50 for other areas of the body.
o    http://dofs.gbi.georgia.gov/00/article/0,2086,75166109_84393031_84525445,00.html#fibers 

http://www.evidentcrimescene.com/cata/evid2/envelopeGlassine.jpg

o   Fibers from items such as clothing, are often found in cases involving an individual’s struggle. When handling evidence, be sure to separate the location of the suspect and the victim so they are not confused with each other. Try to collect the entire item under investigation, however, if this is not possible, first perform a tape lift on the item and then complete a fiber standard of it. To collect transferred fibers, use a clean plastic surface for transport rather than using paper or cards because it may prevent their recovery and comparison. If there is any indication that the victim and suspect contacted a specific source, fiber standards, or known samples, should be taken.