What is the recommended integrity test for sterilization filters?

The bubble test is widely recognized as the recommended integrity test for sterilization filters because it effectively determines the filter's ability to retain microorganisms while allowing sterile fluids to pass through. This test operates on the principle that the filter's pore size is critical for its function; thus, any breach in filter integrity would allow air bubbles to be formed when the filter is immersed in water or another liquid. If bubbles are observed escaping from the downstream side of the filter, it indicates a compromise in its barrier properties, confirming that the filter is not performing as intended.

In contrast, other methods such as the bacterial endotoxin test or the vacuum test serve different purposes in the realm of sterility assurance and do not specifically assess the physical integrity of the filter itself. The bacterial endotoxin test, for instance, measures the presence of endotoxins, while the vacuum test typically evaluates the ability of the system to maintain a vacuum, which is not directly related to filter integrity. An integrity check might refer to various methods applied, but it does not pinpoint the specific bubble test method that is most commonly endorsed for simultaneous assessment of microbiological retention and filter integrity.