ASTM – F2391 Standard Test Method
The ASTM F2391-05 Standard Test Method for Measuring Package and Seal Integrity Using Helium as the Tracer Gas serves to establish the use of helium as an effective Container Closure Integrity test method that is recognized by the global regulatory community. Going back over 20 years, the LDA leadership team served on the ASTM Sub-Committee that worked to establish this procedure that is recognized worldwide.
The ASTM F2391-05 test method allow the user to carry out package and seal integrity testing with sufficient sensitivity to quantify seals to extremely low levels of sensitivity. With the use of seal-isolating leak testing fixtures, packages constructed of various materials can be tested in the full range of seal performance requirements and enable this procedure to effectively be used for a wide variety of applications inclusive of:
- As a design tool for new container and package systems
- For tooling qualification programs,
- Manufacture, Packaging and Sealing Process setup
- Routine Process validation
- Quality assurance monitoring
- Research and development.
Key testing components covered under this test procedure include the use of Helium as a tracer gas, the use of a helium mass spectrometer leak detector as well as the use of custom designed package/product test fixtures. It should be noted that most applications of helium leak detection are destructive, in that helium needs to be injected into the package after the package has been sealed. The injection site then needs to be sealed externally. Alternatively, if helium can be incorporated into the headspace before sealing, the method can be non-destructive as helium simply needs to be detected escaping the sealed package. Specific test method steps using the Vacuum Mode include place of the sample in a closed fixture and drawing vacuum that will enable helium to escape via any holes, defects or unwanted alterations in the package system. The range of sensitivity levels are described according to the following criteria:
- Large leaks — 10-2 Pa·m 3/s to 10-5 Pa·m3/s (10–1 cc/sec/atm to 10-4 cc/sec/atm).
- Moderate leaks — 10-5 Pa·m 3/s to 10-7 Pa·m3/s (10-4 cc/sec/atm to 10-6 cc/sec/atm).
- Fine leaks — 10-7 Pa·m 3/s to 10-9 Pa·m3/s (10-6 cc/sec/atm to 10-8 cc/sec/atm).
- Ultra-Fine leak — 10-9 Pa·m 3/s to 10-11 Pa·m3/s (10-8 cc/sec/atm to 10-10 cc/sec/atm).
As referenced, this test method can be quantitatively used on a wide variety of package types to include flexible, semi-rigid and rigid container and package systems. The Leak Detection Associates Team can help you define and validate the helium based leak testing method and process that will be most effective for your container and product combination.
