Quality Control Protocol for Empty Cosmetic Tubes

1. Visual & Dimensional Inspection:
Tubes are sampled for defects such as scratches, dents, discoloration, or ink smudges. Critical dimensions (body length, cap diameter, shoulder width) are verified against specifications using calibrated gauges to ensure compatibility with filling and capping machinery.

2. Material & Construction Integrity:
Material composition certificates are reviewed for compliance (e.g., PE, PETG, ALU). The tube body and cap seam integrity are checked for leaks via air pressure testing. Tube thickness is measured at key points to guarantee durability and proper barrier properties.

3. Functional Performance:
Closure systems (caps, flip-tops, snaps) are tested for secure fit, smooth operation, and leak resistance. The dispensing orifice is inspected for correct size and finish. For screw caps, thread engagement is verified.

4. Cleanliness & Hygiene:
Interior and exterior surfaces must be free from dust, oil, and particulate contaminants. Microbial limits are confirmed per agreed standards. The packaging environment is controlled to maintain cleanliness.

5. Documentation & Traceability:
Each batch is accompanied by a Certificate of Analysis. Lot numbers on cartons and individual tubes (if applicable) ensure full traceability throughout the supply chain.

Non-conforming batches are quarantined for review. This protocol serves as a baseline and can be customized per specific technical agreements.