Supporting vaccine distribution through seal integrity testing

One of the UK’s largest pharmaceutical contract manufacturing companies needed a reliable method for testing the seal integrity of their life-saving vaccines. Here is how we helped

The challenge


Serving both the domestic and global market, our client required a reliable method for testing the seal integrity of their products to safely distribute their life-saving vaccines and other injectibles around the world. This is essential for transporting vials so that the pharmaceutical material they contain is not compromised in any way.


Whilst there is a method in the Pharmacopeia (European, US and Japanese Pharmacopeia) for testing the integrity of multidose vials, there is no method for assessing the seal integrity of single use containers – this was the challenge that the client required RSSL to address.

Our approach




We have extensive experience in testing seal integrity (as per the European and US Pharmacopeia) on multidose containers (rubber closures) and have provided this service for many clients. At RSSL, packaging integrity is assessed by the following methods:

  • Microbial ingress to the drug product within a vial using a microorganism such as Brevundimonas diminuta
  • Vaporised Hydrogen Peroxide (VHP) ingress test
  • The dye ingress method.


Following in-depth discussions with the client about their needs, our expert team developed a validated method for single use containers that is an adaptation of the European Pharmacopeia (General Chapter 3.2.9, visible dye ingress). This fitted the client’s specific needs, as well as adhering to ICH Q2 and GMP guidelines.


Our team applied their extensive knowledge and experience on closure integrity testing and pharmacopeial validation/verification studies to meet the client’s needs. We successfully adapted the pharmacopeial method for a variety of purposes, enabling the seal integrity of containers differing in size, shape, and material, to be rigorously tested.



Our ability at RSSL to adapt existing methods to solve a specific client’s need led to the development of robust qualitative and quantitative methods that produce quick and reliable results. This innovative and flexible approach also greatly reduced the customer’s project timelines. Furthermore, with these robust methods now validated, the client has the reassurance that they can approach us to test the seal integrity of future products.


Since the conclusion of the project, we have been able to apply the new seal integrity testing methods to assess other products, including on the seal of a medical device used in cancer removal.







Explore RSSL's vaccine services

Contact us

Call us on either number below

Switchboard: +44 (0)118 918 4000

Customer Services: +44 (0)118 918 4076

We value your trust when sharing your personal data with us. We always treat your data in a fair and respectful manner limited to the purpose above mentioned. If you would like to know more about how we handle your data, please read our privacy notice.