A representative sample is taken and the individual fibre length is measured. These values are arranged accordingly and the mean and coefficient of variation are calculated. This method is mainly used for the man made staple fibres as the variation in length is not much.

The fibres are straightened and placed on an oil plate and the individual length of fibres (around 300-500) is measured.

(A) Hand stapling method : (By trained classers):

Selecting a sample and preparing the fibres by hand doubling and drawing to give a fairly well straightened tuft of about ½ inch wide.

This is laid on flat black background and the staple length is measured.

The shorter fibres will lie in body of the tuft and extreme ends (tips) will not be the limits used for measurement of staple length.

The classer chooses the length where there are reasonably well defined edges.

Subjective in nature, so difference in results between classers.

(B) Comb Sorter Method:

A tensile test, also known as tension test, is probably the most fundamental type of mechanical test you can perform on material. Tensile tests are simple, relatively inexpensive, and fully standardized. By pulling on something, you will very quickly determine how the material will react to forces being applied in tension. As the material is being pulled, you will find its strength along with how much it will elongate.

For most tensile testing of materials, you will notice that in the initial portion of the test, the relationship between the applied force, or load, and the elongation the specimen exhibits is linear. In this linear region, the line obeys the relationship defined as "Hooke's Law" where the ratio of stress to strain is a constant, or . E is the slope of the line in this region where stress (σ) is proportional to strain (ε) and is called the "Modulus of Elasticity" or "Young's Modulus".

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