Visual Inspection and Grading of Fabrics

In trade relationships between sellers of fabrics and their customers, a system of defect analysis or defect grading must be agreed upon and in use. At the core of any grading system is simplicity and accuracy. The system must be clearly stated and easy to execute. Of various systems used worldwide, the “4-poinr and “10-poinf’ systems are the most common. The actual method used in any relationship must be agreed upon by all parties as the standard. This discussion will cover these grading methods in a very fundamental manner, and these discussions should not be automatically adopted as a standard method. Various world standards organizations such as ASTM should be referred to for an actual standard method.

Defect Classifications (Major/Minor Defects)

Defects depicted in this CD have been classified as “Major or Minor” defects and by category. These classifications are based upon the judgment and experience of fabric graders. It must be conceded that all “pointable” defects do not result in the determination of product {end item) seconds. Further, it must be understood that certain small or minor defects may be acceptable in certain areas of an end item (garment or home product) while being unacceptable in others, and that a large percent of small or minor defects are lost in the cutting and fabricating of end items. For these reasons, it seems logical that the quality of a fabric, represented by a point value, should be more reliable and correlative to end item quality and fabric utilization if these facts are taken into account.

It is known that across the industry almost all conditions exist, so that a minor defect to one end use may be a major to another and vice versa, but if the nature of the fabric and the demands of an end use are understood, there should be little problem relating quality determined by the major/minor concept. The definitions against which these defects have been classified are as follows:

Major/minor defects defined:

Major: A defect severe enough, if exposed, to place an end item in seconds.

Minor: An imperfection that may or may not cause a second, depending upon its location in the end item and/or its chance of being lost in fabrication.

In many agreements, a major defect may be severe enough that it carries a connotation of “critica/H. This means that this defect by itself would cause an entire roll to be rated as a second or worse. Where applicable, the purchaser and the supplier may agree upon the classification, location, maximum size of a fabric characteristic, and frequency of occurrence that shall not be counted as a defect. In any case, the purchaser and the supplier must agree on a list of defects to be used in grading fabric as well as their severity.

The total shipment shall be rejected if the sample inspected exceeds the maximum acceptable defect level mutually agreed upon by the purchaser and supplier.

Defect Category Classification:

Defects depicted in this CD have been placed into categories based upon their similarity of appearance and effect upon visual quality, and general utilization of the fabric. For example, all defects that result in a fine vertical line are classified within a category. As a result of defect grouping, the use of these general classifications can serve to simplify inspection reports and still render useful information.

Definitions of categories are as follows:

A narrow or fine-lined length or warpwise defect of a continuous or lengthy nature.

It is important to remember that the number of points assigned to a specific defect will tend to further establish its size and nature.

System of Visual Quality Evaluation for Woven and Knitted Fabrics

Part 1 – Domestic System of Measurement

Part 1A – Metric System of Measurement

Part 2- Point Systems

Various point systems are in use worldwide. The most common are the “Four­ Point” and “Ten-Point” systems. The following are brief summaries of these systems.

The Four-Point System

Defect Length (minimum to maximum)

Assign no more than a total of 4 points to any one linear yard or meter of fabric, regardless of the number or size of the detected individual defects.

Assign 4 points to each consecutive linear meter or yard in which a continuous running defect exceeds 9 inches or 230 millimeters.

Assign 4 points to each linear meter or yard of fabric where the useable width is less than the minimum specified.

Assign 4 points to each seam or other full width defect or seam if applicable.

Calculate the total number of points expressed in points per 100 square yards or 100 square meters. Expressions for 100 linear yards or 100 linear meters can also be agreed upon. (See Part 1.)

The Ten-Point System