What is ASTM D3078 and Leak Test of Flexible Packaging

ASTM D3078 standard is to identify the gross leaks in flexible packaging containing headspace gas by bubble emission.

ASTM D3078 Standard for Leak Test

ASTM D3078 standard comes to that small leaks may not be detected by this procedure. The note is that viscoelastic effects on the products, or entrapped air, become significant and prevent passage through small openings. The size of the leak detected is dependent upon the products contained, the nature of the packaging material, and the test parameters selected.

Leak Test Method

The bubble leak packaging test needs two fundamental pieces of equipment.

One is the vacuum chamber which shall be the transparent container that is able to withstand approximately one-atmosphere pressure differential. The vacuum chamber needs to be fitted with a vacuum-tight cover. Some components shall be connected to the chamber cover, including a vacuum gauge, an inlet tube from a source of vacuum, and an outlet tube to the atmosphere.

Another important part is the immersion fluid. The most common-used immersion fluids for bubble leak testing are water, denatured alcohol, mineral oil, etc. The test fluid and sample must be at equilibrium with normal room temperature.

Positive pressures inside the package after the vacuum is drawn can force the product to plug small leaks, and emit bubbles.