Reliability of Hair/fiber crime scene data

In most cases, where tissue is left on the hair, hair/fiber analysis is 100% accurate, due to scientist being able to extract DNA from the tissue to create an exact match. When there is no left over tissue present though, the list of possible people who could have shed the hair is very drastically narrowed. It is narrowed by the scientist being able to pinpoint the hair to certain races or types, such as black people hair, Caucasian hair, color-treated hair, Asian hair, a specific animal hair, or synthetic hairs, such as cotton, nylon, polyester, or wool. Also, if they find that the hair sample is complete, as in it was not cut, tore, or tampered in anyway, they can use the hair length to even shorten the list of possibilities, because a man with a shaved head is not going to have the same hair length of a woman with hair down to her waist.