The water test could be a good indication to evaluate the effectiveness of the sterile barrier system of rigid sterilization containers.  
[Full paper ]
L. Decarout, C. Lambert, L. Choisnard, C. Andonian, C. Fayard
Annales Pharmaceutiques Françaises, 2018, 76(6), 464-472
The objective is to check the maintaining performance of filter barrier in sterilizations containers with the leakage rupture the junction tank/lid of the container. In order to control the good sealing performance, we use the water leak test as described in the normative document AFNOR FD S98-053. Does the leakage rupture cause the contamination of containers during the storage or transport between two sterilization units? Method. — We use 5 sets of 3 different containers (the first without barrier system (positive control), the others with barrier system (the second with positive water test and the third with negative water test)). The containers are sterilized after having positioned triptyc soy agar (TSA) plates at the bottom. In a closed chamber test, the containers are exposed with an aerosol of Micrococcus luteus under stress of an overpressure (25, 50 or 75 mbar) simulating atmospheric pressure variations. Each triptyc soy agar (TSA) plates are incubated during 5 days at 37◦C for bacterial identification. Results. — At 25 mbar, 74% of containers having a leakage with a water test let the microorganisms ingress despite the filter barrier. The results confirm that the overpressure increases the level of bacteria in containers. Furthermore, the containers with positive water test are more contaminated than containers with perfect sealing. The effectiveness of the sterile barrier system is evaluated by the logarithmic reduction value (LRV).