An indispensable part of the garment industry is to conduct needle detection before finished garments leave the factory. This is especially necessary for Japanese, American and European markets.

Needle detection is done to check whether there are any broken needles in the accessories or garments during the manufacturing process that can cause injury to consumers, particularly to children.

Below are 4 factors that causes garments to fail the needle detection test.

1. Manufacturing process

Garment manufacturing includes certain processes. Sometimes garments may not pass through the needle detection test because the special treatment applied over them must not have been dealt properly.

Under below circumstances the needle detector will alarm.

  •          Metal powders stick to fabrics during manufacturing and sewing.

  •          Metallic debris are left in the impact area after the sewing needle hits against the zipper.

  •          Some articles that won't pass needle detector adhere to to garments after special washing process or other treatments.

  •          Certain dyestuff will result in garments' failing to pass the detection.

2. Needle detectors

Almost all needle detectors are able to ensure the accuracy of the detection. However, the testing result will be inaccurate, if the garments are placed in the area that has extreme strong or weak sensitivity or if the garments are not placed well in the detecting area.

In addition, the detectors will also alarm falsely if magnetic substances or dust stays on the conveyor belt.

3. Garment accessories

Various accessories, such as buttons, zippers, interlining and threads, are usually attached to garments to ensure decoration and normal function.

The detector may be triggered because of the attachment or special treatment of certain accessories or trimmings. Therefore, the garments will not pass through the needle detection.

Under below circumstances the garments will not pass the detection

  •        Garments are attached with innumerable metal accessories even though every single item meets the needle detection standard.

  •          Metal accessories have magnetic metal elements like iron, cobalt and nickel.

  •          Zippers have large or circle pullers.

  •          Garments do not take off unqualified labels or hang-tags.

4. Broken needles

The essential component of a sewing needle comprises magnetic metals. If broken needles are left involuntarily in the garments, then the detector will alarm.


SBS zipper can support needle detection depending on customer's request and SBS ensures that zipper products can satisfy specified standards and pass the needle detection.