Burst Testing

There are two roads of testing necessary to package integrity testing: seal strength testing and leak integrity testing. Seal strength testing is valuable to ensure that package contents don't escape, and that protective barriers remain intact, under stresses from transport, shelf life and normal usage. Seal strength tests include the Burst, Creep and Creep-to-Failure tests.

Per ISO 11607 guidelines: "the intention of packaging for terminally sterilized medical devices is to maintain the sterility of the product with respect to its intended use, the shelf life, transport, and storage conditions", i.e. to see that the packaging material and process provide a package that will withstand the sterilization and packaging processes and maintain that sterile barrier for the life of the product. This would be equally applicable to food products that have been packaged to protect the product until in the hands of the customer. This is a twofold objective: first, to ensure the integrity of the sealed packag, and second, to assure that no weaknesses in the sealed areas of the package performs adequately, you must be sure that the package is able to maintain the integrity of both  the seals and the materials under stress. This implies that your package testing system must include both package integrity testing and seal strength testing, two complementary but very different procedures. Package integrity may be thought of as a "leak test" of the package - is there a failure in the materials or process that allows contamination to enter? Seal strength testing, on the other hand, measures an attribute of the seal, which is designed to ensure that the seal presents a microbial barrier to at least the same extent as the rest of the packaging. Both testing streams are important to your final package analysis.

Test-O-Pac Industries has recently aqured the BT Integra-Pack general use package tester, which is suitable for the food industry, medical device packaging, industrial and electornic device packaging and other applications. BT Integra-Pack conforms to ISO 11607 guidelines for package integrity testing by providing both seal strength and leak integrity tests.

ASTM F1140 Standard Test Methods for Internal Pressurization Failure Resistance of Unrestrained Packages

Significance:

These test methods provide a rapid means of evaluating tendencies for package failure when the package is exposed to a pressure differential. Pressure differentials may occur during processes such as sterilization and transportation.

Test Method A (Burst Test) - Packages are tested in an apparatus that internally pressurizes the package until the package fails. The test measure is the maximum pressure detected before the package fails.

Test Method B (Creep Test) - Packages are tested in apparatus that internally pressurizes the package to a specified pressure and maintains that internal package pressure for a specific time. The test measure is pass/fail.

Test Method B (Creep to Failure) - Packages are creep-tested and held until the package fails. Test setup is similar to that of the Creep Test except the pressure setting will need to be higher to ensure the package fails in a reasonable amount of time (that is, about 15 s). The test measure is the time until failure.