Hair+Analysis

 Hair Analysis Fibres can be found in a very wide variety of materials. These include: Hair is very useful for identification because it does not rot away as quickly as other parts of a body. Each person's hair is distinctive, not just in colour and texture but in the //trace elements// it contains. These trace elements reflect an individual's diet, home and work environment and even the shampoo and soaps they use.
 * Animal fibres. Examples are hair, wool and fur.
 * Vegetable fibres. Examples are cotton and hemp.
 * Mineral fibres. An example is asbestos.
 * Synthetic fibres. Examples are nylon and polyester.

Hair can be tested to see if it comes from a human or an animal. Even the area of the body that a questioned hair came from can be identified. The race of the person can also sometimes be determined. Hair found at a crime scene can be matched to the person who left it there. Similarly fibres can be matched to the clothing they came from. If the fibres at a crime scene were found to have come from a popular jumper sold in large numbers from chain stores around the country, then obviously less importance would be placed on it as a piece of evidence. On the other hand, even if they are commonly found, if several different fibres from a crime scene match up with the suspects clothes (e.g. fibres from a jumper, shirt and jeans) then the probability of finding another suspect with a similar combination of clothing is very slight. In this case, the police would have a much stronger case to present in court.

Forensic scientists look carefully for fibres and hairs at a crime scene. Magnifying glasses are often used to help locate samples. If samples are found they are collected using tweezers and placed in sterilised containers for analysis. In crimes of violence, or sex crimes, where there is physical contact between the criminal and the victim, hairs and fibres from the victim are often found on the criminal and hairs and fibres from the criminal are often found on the victim. Hairs and fibres have been one of the most important ways of positive identification in crimes of this nature.

A forensic scientist may use a special type of microscope called a 'comparison microscope' to compare fibres from the scene of a crime with fibres from a suspect's clothing. If the fibres appear to be the same, it could be that the suspect was at the scene of the crime. Analysis through the microscope can usually identify the fibre although various chemical tests are necessary for man-made fibres. Hair can be analysed under a microscope by comparing the suspect's hair with hair found at the scene. Hairs found at a crime scene can also be matched to the person who left it there using DNA analysis. Modern DNA techniques make it is easy to positively identify a hair!