System and method for detecting a possible loss of integrity of a flexible bag for biopharmaceutical product

A test method using a tracer gas for verifying integrity of a flexible bag in order to detect existence of a possible hole, the test method comprising:

• in a preparation phase:
• providing a testing system comprising an enclosure that delimits a vacuum chamber adapted to be fluid-tightly isolated from outside of the enclosure in an operating configuration of the enclosure;
• providing an injection device suitable for delivery of a tracer gas in the vacuum chamber, the tracer gas being preferably helium;
• placing the flexible bag in the vacuum chamber and connecting a port of the bag to a feeding pipe in communication with a source of a tracer gas;
• performing vacuum suction, in order to obtain vacuum outside the flexible bag in an internal volume of the vacuum chamber;
• performing a gas tracer injection by supplying an amount of tracer gas, by the injection device, in the internal volume outside the flexible bag;
• and
• in a test phase, while said vacuum suction is still performed:
• filling the flexible bag with an amount of the tracer gas at a filling step;
• detecting information representative of the partial pressure of the tracer gas outside the flexible bag in the internal volume, to allow detection of this tracer gas escaping from the flexible bag, by using at least one pressure measurement member;
• then, in a subsequent step, comparing a test result representative of a tracer gas partial pressure drop in the internal volume outside the flexible bag, which is obtained using the at least one pressure measurement member, to at least one reference result, so as to determine if the flexible bag is considered to have or not to have passed the integrity verification.

A testing system for verifying the integrity of a flexible bag, using a gas tracer, comprising:

• an enclosure delimiting a vacuum chamber in which an internal volume is fluid-tightly isolated from outside of the enclosure in an operating configuration of the enclosure;
• a first gas supplying device provided with a feeding pipe for filling the flexible bag at a filling step with gas, via an outlet of the feeding pipe when the flexible bag is placed in the vacuum chamber so as to be surrounded by the internal volume;
• a vacuum suction assembly for performing vacuum suction and extracting gas from the internal volume outside the flexible bag, in a suction mode;
• at least one pressure measurement member for detecting gas partial pressure in a detection area of the internal volume, the detection area communicating with a suction inlet of the vacuum suction assembly;
• at least one source of pressurized gas to be introduced inside the flexible bag;
• wherein the testing system further comprises:
• a second gas supplying device for adding gas in the internal volume outside the flexible bag, the second gas supplying device comprising a feeding member that is:
• distinct from the feeding pipe;
• in fluid communication with a gas source;
• and
• a control unit for controlling the first gas supplying device and the second gas supplying device, and adapted to trigger the second gas supplying device before the first gas supplying device;
• and
• an analysis module to use information representative of evolution over time of gas partial pressure detected by the pressure measurement member before and after the filling step, the analysis module being configured to detect a gas leak on the basis of said information.