Jun 2021

Understanding Blister Package Leak Testing Solutions


Pharmaceutical product manufacturers use packaging materials that offer optimal protection and safety allowing to extend product shelf life. Cold form blister packs are manufactured by sandwiching aluminum foil between Polyvinyl Chloride and nylon films using dry bond lamination technology. They provide complete barrier to moisture, light, oxygen, and other gasses. Its ability to offer complete product integrity and protection has made it a favourable choice for pharmaceutical industry.

Oral and solid dose manufacturers aim at producing high quality and cost effective alternatives while manufacturing innovative, convenient packs for end-users. Due to its high efficiency rate and the ability to provide extended shelf life, the cold form blister packs are being extensively used in healthcare packaging. Many pharmaceutical products including tablets, capsules, drugs, vials, ampoules, syringes or liquid products are often packaged using cold form blister packaging. Infact, growing requirements of pharmaceutical companies worldwide had led to the production of cold form foils such as push-through, peelable, peel-push, tear-open and child-resistant. However, the growing demand for cold form blister packs have accelerated concerns about integrity of blister packaging. Although the amount of environmental contaminants that can enter a package vary based on leak size, with blister packages, even minute leaks can become a problem. Depending on the pressure, temperature and duration of exposure, contaminants can easily find path in the seal or any other microscopic crack. Therefore, it’s important for manufacturers to conduct appropriate container closure integrity tests that ensure quantitative and reliable leak testing solution.

Helium leak testing is one of the most sensitive container closure integrity test methods, used primarily for evaluating integrity of critical parenteral or injectable products. In simple terms, it can be understood as the act of finding leaks in some type of enclosed or sealed system using helium as a “tracer” gas, and measuring its concentration as it escapes due to leakage. Apart from being an ideal solution for ensuring container closure integrity, the technology is also applicable in package design, monitoring product quality, failure analysis and line set up and validation.

Helium is considered an ideal choice of tracer gas because of multiple reasons. Helium is non-toxic, non flammable, non-condensable and its presence in the atmosphere is not more than 5ppm. The small atomic size of helium makes it easier to pass through leaks. Since helium does not react with other materials, it is relatively safe to use. Additionally, compared to other tracer gases helium is less expensive and is available in multiple cylinder sizes. Under this method, a helium leak detector otherwise known as Mass Spectrometer Leak Detector (MSLD) is used to identify and calculate size of the leak.The test part is first connected to a leak detector and then the tracer gas, helium is introduced. In the presence of a leak, helium escapes from the test parts and this partial pressure?is?measured and results are displayed on the meter

Applications of Helium Leak testing

  • Ensuring Container Closure Integrity
  • Using sniffer probe to identify sources of the leak
  • Selecting closure formulation and configuration
  • Seal integrity monitoring during stability studies
  • Using proprietary software to predict shelf- life seal integrity
blister package leak testing, package integrity testing, mass spectrometer leak test, helium leak detection
Popup Popup