Sterile Barrier Testing: Bubble Leak or Dye?

ASTM F2096 bubble leak or ASTM F1929 dye penetration testing: both, either, neither?

The correct answer depends on specific factors of the medical device at hand. Understanding the distinctions between these two sterile barrier performance tests helps you decide which is best suited to your SBS. Using the right test for your medical device or pharma product saves time, money and stress by protecting you against the need to retest.

To help you confirm your knowledge, let’s first identify similarities between ASTM F2096 and ASTM F1929:

  • Both tests evaluate sterile barrier performance from external force.
  • Both tests are ISO 11607-approved for SBS analysis
  • Both use destructive test methods, meaning we have one shot with each sample and all will be rendered unusable.

The differences begin to emerge as soon as you consider the test method names:

  • “Bubble leak” indicates a breach is detected as something comes out of (exits) the packaging.
  • “Dye penetration” indicates a breach is detected as the packaging is penetrated (something enters the package) with dye solution.

A look at test method specifics offers further insight into what makes sense for your product.

ASTM F2096 Bubble Leak

Background: Adopted as an ASTM standard in 2001, the current version of the standard became effective in 2011.

About the Test

By inflating the package under water to a predetermined pressure, the technician observes for even tiny sources of streaming bubbles that indicate a failure. The test sensitivity is 250 μm. Fails can include gross leaks, pinholes substrate holes or channels.

ASTM F2096 is commonly relied on for validation, feasibility and root cause analysis. 

Types of packages ideal for ASTM F2096: A welcome solution for oversized, long and complex configurations, kits and other unique factors. See more about ASTM F2096 Bubble Leak Test industry applications.

ASTM F1929 Dye Penetration 

Background: Introduced in 1998, F1929 was referred to as Standard Test Method For Detecting Seal Leaks In Porous Medical Packaging by Dye Injection.

ASTM F1929-15 is the current version. The update removes the text “or to the interior of the seal” from Section 12 of the report, as it conflicted with intent and scope of the standard. No changes were made to the testing process or in regard to reporting. An earlier update in 2012 renamed the test, replacing Dye “Injection” with “Penetration.” The original standard cited only one test method, dye injection, where three options are now allowed.

About the Test

In this test, dye penetrant is introduced into the package sufficient to cover the longest edge of the package to a depth of about 5 mm (0.25 in.). The package is visually examined along each side in 5-second intervals. The dye will reveal channels or outright leaks at a 50-μm sensitivity. This test detects SBS failures to seals only.

Types of packages for ASTM F1929: Sterile packaging systems with edge seals formed between a transparent material and a porous sheet material.

ASTM F1929 is preferred for OQ/PQ seal evaluation. See more about ASTM F1929 industry applications.

Is Your Sterile Barrier Test Accurate?

As we often try to do, it can be valuable to know some of the things that can go wrong in the validation process. If sterile barrier integrity tests are performed by an inexperienced or untrained tester, your SBS performance and test results are vulnerable to serious inaccuracies, including:

  • False Negatives due to wicking, oxidative sterilization, and bending/folding during dye leak testing
  • False Negatives due to incorrect breathing point pressure and air pockets due to labeling, etc. that are not associated with the sterile barrier during bubble leak
  • False negatives could be reported as failures

If you’ve got a question or believe your results could be compromised by one or more of these “oh-no” scenarios, it’s never too early or too late to enlist to an expert. If all is well, you can proceed with peace of mind. If a risk proves true, you’d certainly rather know it today than down the road.

 

Bubble or Dye?