The short answer
Evaluate leakage on the assembled bottle and closure using an agreed method, contents and conditions. A test on an unclosed bottle cannot establish the sealing performance of the finished pack.
Leakage can involve component dimensions, sealing materials, application settings or handling. A useful investigation records the exact assembly and distinguishes possible causes instead of immediately attributing the issue to one component.
Define the test setup
Identify bottle and closure batches, the test liquid, fill, application method, orientation and conditioning. Let the responsible specialists choose suitable methods and acceptance criteria for the intended pack.
Document failures for investigation
Keep affected samples and record where and when leakage appears. Compare assembly settings and component measurements with the approved references. Recheck the system after any correction or substitution.
Procurement checklist
- Identify the complete assembly and batches.
- Record filling and closing conditions.
- Agree test method and acceptance criteria.
- Retain affected samples and photographs.
- Verify corrective action with repeat testing.
Common question
Does passing a brief inversion check prove long-term sealing?
It demonstrates only the conditions actually tested. Broader storage, use and transport performance needs an evaluation plan appropriate to the complete pack.