Under ISO 2859-1 the sampling plan sets acceptance numbers, but the buyer's defect list decides how each fault is classified. Many buyers treat visible oil or dirt spots on the outside of a garment as major, because customers notice them and return the item, especially on white and light colours. Small marks on inside areas that customers are unlikely to see are often classed as minor. Write the classification by size, visibility and location in your defect list.

Where spots come from

Oil spots usually come from sewing machines: oil from the needle bar or looper area dripping or being picked up by fabric, often near seams. Grey marks can also come from dirty tables, floors, trolleys or hands. A pattern of spots in the same place on many garments points to a specific machine or operation.

Spot cleaning

Factories often clean spots with a spot remover or a cleaning gun. This can work, but it can leave a ring, lighten the colour, damage a print or leave a residue or smell. Ask the factory to clean a few pieces first, then wash them with a named procedure such as ISO 6330 and check whether the spot comes back or a ring appears. Also confirm that the cleaning product is suitable for garments that will be worn next to skin.

What to agree

If cleaning works, ask the factory to sort the whole lot, clean affected pieces and re-present them for inspection. Pieces that cannot be cleaned without a mark should be replaced or rejected. Agree who pays for sorting and re-inspection.

Prevention

Ask the factory about machine maintenance and oil control: regular cleaning, correct oiling, drip guards and using sewing machines with less oil spray where possible. Clean tables and covered bins help, as does checking the first pieces off each line every day. Ask the inspector to note the location of spots so the factory can trace the machine.

For whites and light colours

Consider adding an in-line check for spots on light colours, since cleaning after packing is harder. A light box or good lighting at the final check station helps catch small marks.

Keep photos of each spot type in your defect library, so future inspections classify them the same way.