Fabric Inspection:

Understanding the “Four-Point” and “Ten-Point” Systems

When it comes to fabric inspection, there are two commonly used rating systems: the four-point system and the ten-point system. The four-point system is often used for woven and knitted fabrics, where defects are assigned a score of 1 to 4 based on their size and severity.

Here are the criteria for assigning scores under the four-point system:

1. For defects in the warp and weft direction, the score is assigned as follows:

• One point: Defect length is 3 inches or less.
• Two points: Defect length is greater than 3 inches but less than 6 inches.
• Three points: Defect length is greater than 6 inches but less than 9 inches.
• Four points: Defect length is greater than 9 inches.

2. The following principles apply when assigning scores for defects:

• A. The total score for defects in the warp and weft directions in a single piece should not exceed 4 points.
• B. For serious defects, each defect is assigned a score of 4 points. For example, all holes and tears, regardless of their size, are assigned a score of 4 points.
• C. For continuous defects, such as bars, edge-to-edge color differences, narrow width or irregular width, creases, and uneven dyeing, each defect should be assigned a score of 4 points per piece.
• D. No points are deducted for defects within 1 inch of the fabric edge.
• E. Defects should only be scored if they are visible to the naked eye, regardless of whether they are in the warp or weft direction.
• F. Unless otherwise specified (such as for coated fabrics), only the face side of the fabric needs to be inspected.

Sampling Procedures

The American Association of Textile Chemists and Colorists (AATCC) has established standards for fabric inspection and sampling. Here are the sampling requirements:

• A. The number of samples to be taken is the square root of the total number of yards, multiplied by eight.
• B. The number of cartons to be tested is the square root of the total number of cartons.

The fabric to be inspected should be selected completely at random. When at least 80% of the rolls in a batch have been packed, the textile factory should show the packing list to the inspector. The inspector will then select the rolls to be tested. Once the inspector has selected the rolls, no further adjustments to the number of rolls to be tested or the rolls that have already been selected for testing are allowed. During the inspection, no fabric can be cut from any roll, except for color recording and checking.

Calculating Scores

The scores for each roll of fabric are added up after inspection. The level of acceptance is then determined based on the total score. However, because different fabric widths require different levels of acceptance, the score for each roll of fabric per 100 square yards is calculated using the following formula:

A = (total score x 3600) / (number of yards tested x fabric width that can be cut) = score per 100 square yards

Any roll of fabric that exceeds the specified score is considered a second-grade product. If the average score for the entire batch of fabric exceeds the specified level, the batch is considered to have failed the inspection.

Other Considerations

There are other factors to consider when evaluating the level of acceptance for a roll of fabric. For example, different types of fabric may have different defect tolerances. Additionally, the acceptance level may be affected by the end-use of the fabric, as well as the customer’s specific requirements.

In conclusion, understanding the fabric inspection process and rating systems is crucial