Bombing as a method to accelerate air ingress

Headspace Analysis (HSA) as a test method for leak testing is based on the detection of a certain trace gas in the headspace of the test object. The Bombing Method patented by WILCO allows the gas concentration to change in the event of a leak in the shortest possible time - even for test samples without vacuum in the headspace. This enables the HSA Method to be used for many applications.

The challenge of non-destructive leak detection in liquid-filled containers

In the case of containers that are not sealed with negative pressure or have already been sealed with air, the oxygen content changes very slowly in the event of a leak. This applies to most parenteral packaging filled with liquid such as vials and syringes. In these cases, leak testing using the precise and non-destructive HSA method would only be possible with long waiting times and is therefore not practical. Despite these challenges, the Bombing Method makes it possible to use the HSA method for leak testing.

Our approach to leak testing with the Bombing Method

Bombing involves changing the gas composition of the headspace in a test specimen by means of targeted and controlled changes in the ambient conditions. Possible changes of the environmental conditions are defined cycles with overpressure and/or underpressure or the increase of the concentration of the trace gas, which can be detected by means of the HSA method. In the case of a leak, gas compositions within the test sample change within a short time. These changes can be detected by means of non-destructive HSA method and leaks can be detected accordingly - manually or automatically at full production capacity. The method enables a deterministic leak test according to USP<1207> for sterile packaging materials filled with freeze-dried, powdered or liquid product. Bombing can also be used in combination with the HSA method for packaging materials that have been sealed under vacuum, inert gas or atmosphere in headspace.

Complete solution from one source

Together with our customers we analyze the production process and the packaging material combination and then prepare a risk analysis. We discuss the different options of the testing method and develop the optimal bombing and testing process for you. Our laboratory has an automated, high-precision bombing chamber in which we can map different pressures and gas concentrations as part of the cycle development.

In addition to method development, we offer a broad portfolio of HSA devices for laboratory and production applications.

The advantages of our Bombing Method

  • More than 10 years experience in the development of bombing processes for leak testing of pharmaceutical packaging materials (PDA publication - https://journal.pda.org/content/66/5/434)
  • Reduction of waiting times for gas concentration changes in headspace
  • Use of the HSA method for various packaging materials, even without vacuum in headspace
  • Gas concentration change detection via O2,CO2 and total pressure
  • Deterministic, preferred test method according to USP1207 (alternative to blue bath)
  • Use at high outputs up to 600/min
  • Highest sensitivity with detection of CO2 in headspace
  • Use with alcohol-based products
  • Use with liquid and oil-based products
  • Application independent of filling volume