Diffusive airflow integrity testing

Area of Science:

• Filtration technology
• Microbial retention studies
• Process analytical technology

Background:

• Bubble point testing is a standard method for filter integrity, but can be hindered by diffusive airflows.
• Diffusive airflow measurements offer an alternative integrity test when bubble point testing is not possible.

Purpose of the Study:

• To evaluate diffusive airflow measurements as an integrity test for filters.
• To explore the utility of diffusive airflow testing in various filter applications and validation contexts.

Main Methods:

• Correlating diffusive airflow measurements with organism retention data.
• Defining diffusive airflow curves through multipoint measurements using specific liquid products.
• Implementing single-point diffusive flow testing for production settings.

Main Results:

• Diffusive airflow measurements serve as effective integrity tests, particularly when bubble point testing is interfered with.
• These measurements provide insights into filter incompatibilities, wettability, and clean water flow properties.
• Single-point diffusive flow testing is validated as a standard method for pharmaceutical production integrity testing.

Conclusions:

• Diffusive airflow testing is a robust alternative and complementary method to bubble point testing for filter integrity.
• Product-specific, multipoint measurements are crucial for establishing reliable diffusive airflow curves for validation.
• Single-point diffusive flow testing is a practical and standardized approach for routine production integrity checks.