A helium based test method for verifying the integrity of a blister card holding drug product has been proven to be the most effective approach due to the extreme sensitivity offered. The test method relies on detecting helium sealed in the package system as it escapes through micro-channels in the package. A test sequence begins by placing the package in the test fixture and a vacuum is quickly drawn. The resulting pressure differential causes helium to escape through potential holes or cracks in the package. While under vacuum pressure, flow is directed to the analyzer cell where any escaping helium gas from the blister card is quantitively measured in the cell. Typical test cycle times range from 20 – 60 seconds. Once the test cycle is completed and measurement is recorded, the test chamber is vented to atmosphere and a new sample can be testing. Upon completion of testing for all samples in the defined set, each cards helium concentration value is measured by using the LDA HSAM helium concentration device. This process normalizes the helium leak rate to 100% thereby allowing direct comparison of all test samples along either the production line set-up or package materials being used.
Leak Detection Associates has developed and validated blister card testing methods for many years and has experience with various sizes and material combinations. The LDA team can custom design and manufacture a sample holding chamber specific to the blister card to be tested and can assist clients with development of an effective and suitable method for their specific blister card package.