Embodiments of the invention generally provide an apparatus and method for decontaminating tubing. The invention is particularly suitable for decontaminating tubing in a test system used for certifying a filter in a containment system. In one embodiment, a test system for a containment system is provide that includes a sample system including equipment adapted for testing a filter disposed in a containment system utilizing samples obtained from a downstream sample port and a upstream sample port of the containment system, and a device for reversing a flow within the sample system. In another aspect of the invention, a method for decontaminating tubing is provided. In another embodiment, the method includes flowing a sterilization agent through tubing in a first direction and flowing the sterilization agent through tubing in a second direction.