Pressure differential testing can use vacuum or external pressure methods, with the appropriate approach selected according to the package design, headspace, contents and integrity requirements.
Vacuum testing
Vacuum testing is suitable for packages with a well-defined headspace. Reducing the pressure around the package creates a pressure differential, allowing gas or liquid to escape through leaks in the packaging.
Smithers performs vacuum testing for applications including:
- Gross leak detection, including bubble emission testing in accordance with ASTM D3078
- Evaluation of package and seal performance under differential pressure
- Testing of empty containers for resistance to leakage under air-transport pressure conditions in accordance with ASTM D4991
Vacuum methods can detect gross leaks of approximately 100 µm and above, but are less suitable for detecting smaller leaks, particularly where wet contents could obstruct a leak path.
External pressure testing
External pressure methods apply pressure outside the package, causing test gas or liquid to flow into the package through any leak path.
This approach can apply a greater differential pressure than vacuum testing and does not require the package to have a headspace, making it suitable for pack formats where vacuum methods may not be appropriate.
Talk to our experts about your packaging, integrity requirements and the most appropriate test method for your application.
