Man-made fibers are stronger and durable than natural fibers. Synthetic fibers are not affected by chemicals, rot, or mildew. Most synthetic fibers can be stored wet or dry.

A characteristic of fiber is that its length is at least 100 times its diameter or width. The length of the fiber refers to the number of units spun into yarn or made into a fabric by various methods such as weaving, knitting, braiding, felting, and twisting. The basic requirements for fibers to be spun into yarn include a length of at least 5 millimeters, flexibility, cohesiveness, and sufficient strength. In addition to these properties, high quality fibers have the following characteristics:

• Look and feel: The texture of the fiber.

• Tensile strength: A measure of force required to pull the fiber to the point where it breaks.

• Elasticity: The tendency of the fiber to return to its original shape after it has been stretched or compressed.

• Density: The fiber s weight for a given volume.

• Fineness: The diameter of an individual fiber measured in microns with extremely precise laboratory instruments.

• Durability: The ability of a fiber to retain its original qualities with continuous use.

• Luster: The brightness or reflectivity of fibers.

• Cohesiveness: The ability of fibers to stick together.

• Uniformity: The fiber s resistance to heat, chemicals, and sunlight.